U.S. patent application number 17/457937 was filed with the patent office on 2022-03-24 for method for extraction of an agent from a plant source.
This patent application is currently assigned to Yissum Research Development Company of the Hebrew University of Jerusalem Ltd.. The applicant listed for this patent is Yissum Research Development Company of the Hebrew University of Jerusalem Ltd.. Invention is credited to Rotem EDRI, Sharon GARTI LEVI, Nissim GARTI.
Application Number | 20220088099 17/457937 |
Document ID | / |
Family ID | |
Filed Date | 2022-03-24 |
United States Patent
Application |
20220088099 |
Kind Code |
A1 |
GARTI; Nissim ; et
al. |
March 24, 2022 |
METHOD FOR EXTRACTION OF AN AGENT FROM A PLANT SOURCE
Abstract
Provided are methods for extraction of various agents, e.g.
active agent, from a plant source, specifically with the use of
extraction formulations which are based on micellar liquid
systems.
Inventors: |
GARTI; Nissim; (Ramat
HaSharon, IL) ; GARTI LEVI; Sharon; (Modi'in, IL)
; EDRI; Rotem; (Eilat, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Yissum Research Development Company of the Hebrew University of
Jerusalem Ltd. |
Jerusalem |
|
IL |
|
|
Assignee: |
Yissum Research Development Company
of the Hebrew University of Jerusalem Ltd.
Jerusalem
IL
|
Appl. No.: |
17/457937 |
Filed: |
December 7, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16338280 |
Mar 29, 2019 |
11224628 |
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PCT/IL2017/051101 |
Sep 28, 2017 |
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17457937 |
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International
Class: |
A61K 36/05 20060101
A61K036/05; A23L 33/105 20060101 A23L033/105; A61K 9/00 20060101
A61K009/00; A61K 31/122 20060101 A61K031/122; A61K 47/46 20060101
A61K047/46 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 29, 2016 |
IL |
248148 |
Claims
1.-47. (canceled)
48. An extraction medium for extracting a lipophilic agent from a
plant source containing said lipophilic agent, the extraction
medium being in the form of a microemulsion and comprising at least
one oil, at least one hydrophilic surfactant, at least one
co-surfactant, and no more than 10 wt % of water.
49. The extraction medium of claim 48, wherein said at least one
oil is selected from the group consisting of essential oils,
terpenes, D-limonene, mineral oil, paraffinic oils, phospholipids,
polar lipids, squalenes, sphingomeylins, waxes, vegetable oils,
glycerides, triglycerides, fatty acids and esters of fatty acids,
and liquid hydrocarbons.
50. The extraction medium of claim 48, wherein said at least one
oil being present in the extraction medium at an amount of between
about 0.5 and 20 wt %.
51. The extraction medium of claim 48, wherein said at least one
hydrophilic surfactant is selected from the group consisting of
polyethylene glycol (15)-hydroxystearate (Solutol HS15),
polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan
monopalmitate, polyoxyethylene sorbitan monooleate, and
polyoxyethylene esters of saturated and unsaturated castor oil,
ethoxylated monoglycerol esters, ethoxylated fatty acids,
ethoxylated fatty acids of short, medium and long chain fatty
acids.
52. The extraction medium of claim 48, wherein said at least one
hydrophilic surfactant being present in the extraction medium at an
amount of between about 30 and 85 wt %.
53. The extraction medium of claim 48, wherein said at least one
co-surfactant is selected from the group consisting of
polypropylene glycol, polyethylene glycol, sorbitol, xylitol, PEG
200, PEG 400 and PEG 600.
54. The extraction medium of claim 48, wherein said at least one
co-surfactant being present in the extraction medium at an amount
of between about 1 and 50 wt %.
55. The extraction medium of claim 48, wherein the extraction
medium further comprises at least one phospholipid.
56. The extraction medium of claim 55, wherein said at least one
phospholipid is present in the extraction medium in an amount of
between about 1 and 10 wt %.
57. The extraction medium of claim 48, further comprising at least
one solvent.
58. The extraction medium of claim 57, wherein said at least one
solvent is selected from the group consisting of ethanol, propanol,
isopropanol, acetic acid, and lactic acid.
59. The extraction medium of claim 57, wherein the extraction
medium comprises between about 0.1 and 25 wt % of said solvent.
60. A composition comprising at least 0.1 wt % of a lipophilic
agent from a plant source solubilized within the extraction medium
of claim 48.
61. The composition of claim 60, wherein the lipophilic agent is
selected from the group consisting of astaxanthin, lycopene,
beta-carotene, lutein, eugenol, piperine, anthocyanins, betaine,
oleuropein, trimyristin, curcumin, capsaicin, gossypol, rosmanol,
chlorogenic acid, cinnamaldehyde, flavones, caffeine, isoflavone,
tocopherol, omega fatty acids, chlorogenic acid, caffeic acid,
niacin, nicotinamide, flavonoids, cineole, borneol, thujone,
carnosol, carnosic acid, fumaric acid, behenic acid; and any of
their triglycerides or esters of long chain fatty acids.
62. The composition of claim 60, being a food, a food supplement, a
nutraceutical composition, a cosmetic composition, or a
pharmaceutical composition.
63. The composition of claim 62, being in a form selected from a
gel, a lotion, oil, soap, shampoo, a spray, an emulsion, a cream,
an ointment, capsules, soft-gel capsules, a patch, a solution, a
suppository, and a chewing gum.
64. The composition of claim 62, being a pharmaceutical composition
formulated for delivery of said lipophilic agent topically, orally,
by inhalation, nasally, transdermally, occularly, rectally,
vaginally, or parenterally to a subject.
Description
TECHNOLOGICAL FIELD
[0001] The present disclosure provides methods for extraction of
various agents, e.g. active agent, from a plant source,
specifically with the use of extraction formulations which are
based on micellar liquid systems.
BACKGROUND ART
[0002] References considered to be relevant as background to the
presently disclosed subject matter are listed below: [0003] [1] WO
2008/058366 [0004] [2] A. Spernath, A. Aserin, Advances in Colloid
and Interface Science 2006, 128 [0005] [3] A. Spernath, A. Aserin,
N. Garti, Journal of Colloid and Interface Science 2006, 299,
900-909 [0006] [4] A. Spernath, A. Aserin, N. Garti, Journal of
Thermal Analysis and calorimetry 2006, 83 [0007] [5] N. Garti, A.
Spernath, A. Aserin, R. Lutz, Soft Matter 2005, 1 [0008] [6] A.
Spernath, A. Aserin, L. Ziserman, D. Danino, N. Garti, Journal of
Controlled Release 2007, 119 [0009] [7] S. Fisher, E. J. Wachtel,
A. Aserin, N. Garti, Colloids and Surfaces B: Biointerfaces 2013,
107, 35-42 [0010] [8] R. Deutch-Kolvzon, A. Aserin and N. Garti,
Chemistry and Physics of Lipids 2011, 164(7), 654 [0011] [9] O.
Amsalem, A. Aserin, N. Garti, Colloids and Surfaces, B:
Biointerfaces 2010, 81(2), 422-429.
[0012] Acknowledgement of the above references herein is not to be
inferred as meaning that these are in any way relevant to the
patentability of the presently disclosed subject matter.
BACKGROUND
[0013] Extracts containing various agents from various plant
sources have been used for many years in a plethora of
applications, varying from cleaning and industrial applications to
cosmetic and therapeutic uses.
[0014] One of the methods commonly used to extract lipophilic (or
non-water soluble) active agents from plant sources is extraction
by carrier oils, in which the carrier oil is used as a solvent for
the extraction of the desired lipophilic species from the plant
source.
[0015] Another method often used is extraction by organic solvents,
which are selected amongst solvents capable of dissolving the
desired lipophilic agent. Such extraction requires tailoring of the
solvent for effective extraction of each lipophilic agent, and
often result in low yields of extraction. Further, it is difficult
to remove traces of the solvent from the end product, reducing the
degree of purity and the safety of the resulting extract. Most of
these extractions are found to be insufficient and often leave
undesired traces of the solvent (especially when petroleum ethers
are used). In most cases the extraction by conventional solvents is
not selective, hence necessitating further processing to obtain the
desired material. Further, in most cases the formulations show
inconsistent or limited bioavailability.
[0016] A further method which is used for obtaining extraction of
various compounds from various plant sources is super-critical
CO.sub.2 extraction. In the CO.sub.2 extraction process, CO.sub.2
at super-critical conditions (i.e. high temperature and pressure)
is used as a solvent for the desired lipophilic species. Although
very effective for extracting a variety of compounds from the plant
source, this technique is often more complicated and very expensive
compared to liquid extraction. In addition, this technique is far
from being selective to specific lipophilic agents, and may
concomitantly and indiscriminately extract other lipophilic
products from the plant source.
[0017] Thus, there exists a need for a simple, highly-tailorable
extraction process and extraction medium for extraction of desired
agents from plant sources.
GENERAL DESCRIPTION
[0018] Efficient extraction of lipophilic (or water insoluble)
agents from various natural sources is provided in the present
disclosure by the use of a unique one-pot extraction process. As
further detailed herein, the present disclosure also provides
mediums enabling such extraction, as well as various pharmaceutical
compositions and administration forms comprising it.
[0019] In one of its aspects, the present disclosure provides a
lipophilic agent from a plant (i.e. natural) source, the process
comprising:
(a) obtaining (for example, by mixing) a first mixture comprising a
first quantity of a plant source containing the lipophilic agent
and a first quantity of an extraction medium, the extraction medium
comprising at least one oil, at least one hydrophilic surfactant
and at least one co-surfactant, and optionally at least one
co-solvent; (b) homogenizing the first mixture; and (c) separating
the homogenized mixture into a biomass slurry and an agent-loaded
medium.
[0020] In some embodiments, the lipophilic agent is not a
cannabinoid.
[0021] The extraction media used in the processes of this
disclosure show high extraction efficiency, high loading capacity,
high selectivity, as well as being non-expensive and relatively
easy to use.
[0022] The extraction media of this disclosure are substantially
water-free micellar systems, which may be regarded as oil-in-oil
microemulsions. Microemulsions (MEs) are well-known vehicles for
delivery of drugs because of their spontaneous formation, high
solubilization capacity, low viscosity, transparency and physical
thermodynamic stability [1]. The extraction media of this
disclosure arc a specific, tailored type of microemulsion, which
are an advanced category of delivery vehicles. These systems have
been previously studied and their ability to solubilize non-soluble
drugs and nutraceuticals has been demonstrated [2-7]. The
extraction medium is a self-assembled microemulsion system of
nanodroplets, comprising surfactants and oil. The extraction media
of the present disclosure, as will be explained further herein,
comprise at least one oil, at least one hydrophilic surfactant and
at least one solvent, and may further comprise additional
components such as co-surfactants, co-solvents and phospholipids.
In the present disclosure, the term extraction medium will refer to
such substantially water-free microemulsions, unless otherwise
defined. The terms "microemulsion" and "extraction medium" will be
used interchangeably.
[0023] The extraction medium may be in the form of water-free
concentrates, that can be fully and progressively diluted with
aqueous phase to form O/W microemulsions. The diluted medium
(diluted microemulsion) are nano-sized uniform (mono-dispersed)
structures, exhibiting zero interfacial tensions between the oil
phase and the aqueous phase behaving like Newtonian fluids.
[0024] The extraction medium is self-assembled upon mixing the
surfactants and the oil to form water-free reverse micelles. Upon
dilution with water or aqueous solutions, water-swollen micelles or
water-in-oil nanodroplets are formed, being able to invert into
bicontinuous mesophases in the presence of an aqueous phase, e.g.
water. Upon further dilution, they undergo (umbrella type)
inversion into oil-in-water droplets.
[0025] Without wishing to be bound by theory, the extraction media
are constituted by oil-solvated clusters or short domains of
surfactants, however differ from the classical reverse micelles.
When mixed with small amounts of aqueous media, hydrated and
solvated surfactants are formed, and upon further dilution with
aqueous phase they are easily transform into oil-in-water (O/W)
nanodroplets entrapping into their core the lipophilic agent
molecules. The transformation to O/W microemulsions is spontaneous,
i.e. without the need to employ shearing, mechanical forces or
excessive heating conditions. The lipophilic agent is entrapped in
the core of the reverse micelles and remains at the interface
between the oil phase and the aqueous phase upon dilution during
the bicontinuous region; thereafter lipophilic agent is located in
the core of the droplets once the O/W microemulsion is formed (i.e.
the diluted medium). The interactions (physical complexation)
between the lipophilic agent and the surfactants (as well as the
co-surfactants, when used) allow maintaining the lipophilic agent
within the oil core throughout the structural transformations of
the reverse micelles into a bicontinuous region and finally to the
O/W microemulsion, thus stabilizing the formulation and preventing
undesired release of the lipophilic agent from the oil core.
[0026] The extraction media may be designed to have chemical
compatibility with the lipophilic agents to be extracted, thereby
resulting in integration and interpenetration of the extracted
lipophilic agent into the surfactant and co-surfactants that form
the micelle. This helps to stabilize the loaded medium and supports
high loading of the lipophilic agent within the oil droplets.
[0027] These media are thermodynamically stable, with nano-sized
droplets, which may be safely stored for prolonged periods of time,
without creaming, aggregation, coalescence or phase separation. The
agent-loaded media prepared by the process of this disclosure are
also characterized by a substantially uniform and stable droplets
size, typically in the nanometric scale and having a narrow size
distribution. The stability of the droplet size of the system is of
importance, as changes in the droplet size may impair the release
of the lipophilic agent entrapped (solubilized) within the
droplets. Further, the lipophilic agent-loaded media, when not in
diluted form, are substantially devoid of water, and as such do not
support (or minimize) microbial growth. Further, due to their high
stability and small droplet size, the systems may be sterilized
without the risk of self-contamination in various ways, such as
heat sterilization, filtration through a 0.22 .mu.m filter, UV and
other methods know to the art, without damaging the media's
beneficial structure.
[0028] In the present disclosure, the extraction media are designed
(i.e. by tailoring the composition of the surfactants, oil and
co-surfactants) to extract various lipophilic agents from a variety
of plant source, such that the loaded system (agent-loaded medium)
is substantially water-free (at times devoid entirely of water or
even anhydrous), which can be easily diluted or further formulated
"on demand" and as per application or route of administration with
any type of aqueous solution (buffer, water for injection, saline,
isotonic mixtures and others).
[0029] The lipophilic agent generally refers herein to compounds
which are water insoluble, and may dissolve in fats, oils, lipids,
non-polar solvents and other specific solvents (such as acetone,
DMF, DMSO, DMA). Such agents may include, for example, astaxanthin,
lycopene, beta-carotene, lutein, eugenol, piperine, anthocyanins,
betain, oleuropein, trimyristin, curcumin, capsaicin, gossipol,
rosmanol, chlorogenig acid, cynamaldehyde, flavones, caffeine,
isoflavone, tocopherol, omega fatty acids (including DHA and EPA),
chlorogenic acid, caffeic acid, niacin, nicotinamide, falvanoids,
cineole, borneol, thuj one, carnosol, carnosic acid, fumaric acid,
behenic acid and similar triglycerides and esters of long chain
fatty acids or their corresponding triglyceride.
[0030] In the context of the present disclosure, the term is meant
to encompass also isomers, derivatives, analogues or precursors of
these agents.
[0031] When referring to the plant source, it is to be understood
that the raw-material from which the lipophilic or water insoluble
agent is extracted in a plant or a vegetative material. It is to be
understood that the term also means to encompass extractable raw
material being or derived from algae, microalgae, fungus, mold,
yeast, etc. The plant source may be any naturally-occurring strain,
any horticultural variant, cultivated or engineered strain of the
relevant plant genus from which the lipophilic agent is to be
extracted.
[0032] For example, for the extraction of astaxanthin, the plant
source may be an algae or a microalgac, typically Haematococcus
pluvialis. In another non-limiting example, lycopene may be
extracted from any plant source containing lycopene such as
tomatoes, water melon, etc. Another example is extraction of
chlorogenic acid from green coffee beans.
[0033] Similarly, the process described herein may be used to
reduce the content of a non-desired or toxic lipophilic agent (such
as gossipol) in a plant-based material, thereby obtaining a
purified plant-based material.
[0034] In some embodiments, the plant source may be selected from
althea, American ginseng, Berberis (barberry), belladonna,
billberry, borage, catnip, cayenne pepper, Geranium (cranesbill),
Echinacea, Fallopia multiflora (Fo-Ti), ginger, Hydrastis
canadensis (goldenseal), Athyrium (lady-fern), licorice, cinnamon,
coffee beans, marijuana, Silybum marianum (milk thistle), parsley,
peppermint, rosemary, Serenoa repens (saw palmetto), Scutellaria
(skullcap), Hypericum perforatum (st. John's wort), cherries,
Melaleuca (tea tree), valerian, Salix alba (white willow),
Dioscorea (wild yam), Hamamelis (witch hazel), lavender, stevia,
agave, vanilla, acai, Moringo gurana, aloe, nutmeg, dill,
fenugreek, aronia (chokeberries), pomegranate, Salvia hispanica
(chia), Linum (flax), Lycium barbarum, spirulina, Sargassum
siliquastrum, Piper nigrum (black pepper), Olea europaea (olive),
Pimenta (allspice), Curcuma (turmeric), carrots, tomatoes,
beetroot, Tagetes (marigold), and others.
[0035] The process of this disclosure may be carried out utilizing
any part of the plant source that may contain the desired
lipophilic agent; i.e. in some embodiments, the plant source is
selected from flowers, inflorescences, buds, fruit, pericarp,
seeds, leaves, stems, stalks, bulbs, roots, and any mixture
thereof.
[0036] The plant source may be provided in any desired form, for
example, as a powder, granules, pellets, tablets, shredding, puree,
mash, desiccated plant part, or a non-treated plant part (e.g.
non-treated leaves, seeds, inflorescence, etc.). The plant source
may be provided fresh, dried, freeze-dried, lyophilized,
semi-desiccated or desiccated.
[0037] The term agent-loaded medium is meant to denote an
extraction medium as described herein, into which at least 200 ppm
(0.02 wt %) of lipophilic agent is solubilized. In some
embodiments, the agent-loaded medium comprises between about 0.02
and 20 wt % of the lipophilic agent. In other embodiments, the
agent-loaded medium may comprise between about 0.02 and 15 wt % of
lipophilic agent, between about 0.02 and 10 wt % of lipophilic
agent, between 0.02 and 5 wt % lipophilic agent, or between about
0.02 and 0.5 wt % of lipophilic agent. In some other embodiments,
the agent-loaded medium may comprise between about 0.5 and 20 wt %
of lipophilic agent, between about 1 and 20 wt % of lipophilic
agent, between 1.5 and 20 wt % lipophilic agent, or between about 2
and 20 wt % of lipophilic agent.
[0038] As noted above, the microemulsion used for extraction in the
process of this disclosure comprises at least one oil, at least one
hydrophilic surfactant and at least one co-surfactant, and
optionally comprising at least one co-solvent.
[0039] In the context of the present disclosure, the term oil
refers to natural or synthetic oil in which the desired lipophilic
agent may be solubilized. The oils used in the extraction media of
this disclosure may be approved for administration to a subject. In
some embodiments, the oil may be selected from essential oils (such
as R-limonene, D-limonene, terpenes or terpene-less), mineral oil,
paraffinic oils, phospholipids, polar lipids (squalenes,
spingomyelins), waxes, vegetable oils, triglycerides, glycerides,
fatty acids and esters of fatty acids, liquid hydrocarbons and
others, and any mixture thereof.
[0040] According to some embodiments, the oil may be selected from
medium-chain triglycerides (MCT), olive oil, soybean oil, canola
oil, cotton oil, palmolein, sunflower oil, corn oil, isopropyl
myristate, oleyl lactate, coco caprylocaprate, hexyl laurate, oleyl
amine, oleic acid, oleyl alcohol, linoleic acid, linoleyl alcohol,
ethyl oleate, hexane, heptanes, nonane, decane, dodecane,
D-limonene, neem oil, lavender oil, peppermint oil, anise oil,
menthol, capsaicin, grape seed oil, pomegranate oil, avocado oil,
sesame oil, fish oil, omega oils and omega fatty acids, and similar
essential oils and mixtures thereof.
[0041] According to other embodiments, the oil is selected from at
least one medium-chain triglyceride (MCT), castor oil,
R-(+)-Limonene, glycerol, isopropyl myristate, ethyl laurate, olive
oil, benzyl alcohol, laurylacetate, lauryl lactate, oleyl lactate,
cetyl alcohol, ethyl hexyl laurate, ethyl hexyl oleate, and
others.
[0042] The oil may be present in the extraction medium, according
to some embodiments, at an amount of between about 0.5 and 20 wt
%.
[0043] The extraction media comprise at least one hydrophilic
surfactant. The term hydrophilic surfactant refers to ionic or
non-ionic surfactants having a hydrophilic nature, i.e. a
surfactant having an affinity for water. Exemplary surfactants are
polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan
monopalmitate, polyoxyethylene sorbitan monooleate, and
polyoxyeyhylene esters of saturated and unsaturated castor oil,
ethoxylated monglycerol esters, ethoxylated fatty acids,
ethoxylated fatty acids of short and medium and long chain fatty
acids, and others.
[0044] In some embodiments, the at least one hydrophilic surfactant
is selected from Solutol HS15 (polyethylene glycol
(15)-hydroxystearate), polyoxyethylenes, ethoxylated (20EO)
sorbitan mono laurate (T20), ethoxylated (20EO) sorbitan
monostearate/palmitate (T60), ethoxylated (20EO) sorbitan mono
oleate/linoleate (T80), ethoxylated (20EO) sorbitan trioleate
(T85), castor oil ethoxylated (20EO to 40EO); hydrogenated castor
oil ethoxylated (20 to 40EO), ethoxylated (5-40 EO) monoglyceride
stearate/plamitate, polyoxyl 35 and 40 EOs castor oil. According to
other embodiments, the hydrophilic surfactant may be selected from
polyoxyl 35 castor oil, polysorbate 40 (Tween 40), polysorbate 60
(Tween 60), polysorbate 80 (Tween 80), Mirj S40, Oleoyl
macrogolglycerides, Polyglyceryl-3 dioleate, ethoxyllated hydroxyl
stearic acid (Solutol HS15), sugar esters (sucrose mono oleate,
sucrose mono stearate), polyglycerol esters (10 glycerol mono
oleate, 6 glycerol monolaurate, or mono oleate); and soaps such as
sodium-, potassium-, ammonium-, ethanol-amine- of a short and
medium chain saturated and unsaturated fatty acids (e.g. sodium
laurate, sodium oleate, sodium linoleate, sodium linoleneate and
others). The extraction medium may comprise, by some embodiments,
between about 30 and 85 wt % of said hydrophilic surfactant.
[0045] The term co-surfactant should be understood to encompass any
agent, different from the hydrophilic surfactant, which is capable
(together with the hydrophilic surfactant) of lowering the
interfacial tension between the oil phase and an aqueous phase to
almost zero (or zero) allowing for the formation of a homogeneous
mixture and geometrical or physical integration of the agent to the
interface or the oily core of the nanostructure. According to some
embodiments, the co-surfactant is selected from polyols,
diglycerides, polyoxyethylenes, and others.
[0046] The co-surfactant may be at least one polyol, i.e. an
alcohol containing at least 2 hydroxyl groups, for example ethylene
glycol, glycerol, polyethylene glycol, polypropylene glycol,
sorbitol, mannitol, lactitol, xylitol and others.
[0047] In some embodiments, the co-surfactant may be selected from
glycerol, polypropylene glycol, polyethylene glycol, sorbitol,
xylitol, PEG 200, PEG 400 and PEG 600. In some embodiments, the
co-surfactant is present in the microemulsion at an amount of
between about 1 and 50 wt %.
[0048] In some embodiments, the extraction medium may further
comprise at least one solvent. The term solvent refers to an
organic compound, different from the oil, which is miscible in the
oil and together therewith forms a homogenous oily phase that
dissolves and stabilizes the lipophilic agent. The solvent may,
according to some embodiments, be selected from liquid
hydrocarbons, alcohols, and others. According to some embodiments,
the solvent may be selected from ethanol, propanol, isopropanol,
acetic acid, lactic acid, fumaric acid, malic acid, tartaric acid
and succinic acid and others. In some embodiments, the solvent may
be present in the medium at an amount of between about 0.1 and 25
wt %.
[0049] The co-solvent may be a polyol, such as propylene glycol,
glycerol, xylitol or short chain alcohols such as ethanol,
propanol, iso-propanol and others.
[0050] In some embodiments, the extraction medium further comprises
at least one phospholipid. Phospholipids such as soy lecithins,
rapeseed lecithins, corn or sunflower lecithins, egg lecithins,
hydroxylated phospholipids, lyso phospholipids, phosphased
phospholipids, hydrogenated phospholipids, Epicorn 200, Phosal 50
PG, dioleyl phospatidylcholine (DOPC), oleyl palmytoyl
phosphatidylcholine (POPC), and the corresponding serines, ethanol
amines, glycerol, and others may be used. According to such
embodiments, the medium may comprise between about 1 and 10 wt % of
phospholipids.
[0051] As a man of the art may appreciate, the ratio between the
medium's components may be tailored to endow certain
characteristics to the medium (such as, desired agent loading,
selectivity of extraction, droplet size, viscosity, electrical
charge, etc.).
[0052] Various active agents are extracted from the plant source by
utilizing the extraction medium of the present disclosure. The term
extraction or any lingual variation thereof, is meant to denote the
transfer of a desired lipophilic agent from the plant source to a
solubilizing oily phase of the medium. The process of the present
disclosure comprises obtaining a first mixture of a first quantity
of the plant source and a first quantity of the extraction medium,
for example by mixing. Mixing may be carried out by any suitable
known method that does not involve sheer-mixing, for example,
manual mixing, magnetically stirring, mixing by pedals, etc.
[0053] In some embodiments, the weight ratio (wt/wt) of the first
quantity of plant source to the first quantity of medium is between
1:5 and 1:80. In other embodiments, the weight ratio (wt/wt) of the
first quantity of plant source to the first quantity of medium may
be between 1:7 and 1:70, 1:10 and 1:50, 1:12 and 1:70, or even
between 1:15 and 1:60.
[0054] In the next stage, the first mixture is homogenized.
Homogenization, or any lingual variation thereof, refers to the
process of applying sheer forces onto mixtures to break down both
the plant source (i.e. reduce the plant source in size) and the
extraction medium and blend them to form intimate contact that
permits extraction of the lipophilic agent from the plant source
into the extraction medium. It is of note that as the systems used
in the process of this disclosure have a nanometeric size
structure, the homogenization has little impact with respect to the
micelles size and/or structure of the extraction medium.
[0055] In some embodiments, the homogenization (i.e. of step (b))
may be carried out for a period of time of between about 1 minute
and about 120 minutes. In other embodiments, the homogenization is
carried out for a period of between about 1 minute to 45 minutes,
between about 1 minute and 30 minutes, or even between about 1
minute and 20 minutes. In some other embodiments, the
homogenization may be carried our between about 5 minutes and about
120 minutes, between about 10 minutes and about 120 minutes,
between about 15 minutes and about 120 minutes, or even between
about 20 minutes and about 120 minutes.
[0056] According to some embodiments, homogenization may be carried
out at a pressure of between about 500 and 6,000 psi.
[0057] In some embodiments, the homogenization may be carried out
at a temperature of between about 5 and about 70.degree. C. In
other embodiments, the homogenization may be carried out at a
temperature of between about 5 and about 70.degree. C., 10 and
about 70.degree. C. 15 and about 70.degree. C., between about 20
and about 70.degree. C., between about 25 and about 70.degree. C.,
or between about 30 and about 70.degree. C. In some other
embodiments, the homogenization may be carried out at a temperature
of between about 10 and about 65.degree. C., between about 10 and
about 60.degree. C., between about 10 and about 55.degree. C.,
between about 10 and about 50.degree. C., between about 10 and
about 45.degree. C., or even between about 10 and about 40.degree.
C. In further embodiments, the homogenization may be carried out at
a temperature of between about 15 and about 60.degree. C., between
about 20 and about 50.degree. C., or between about 25 and about
45.degree. C.
[0058] Homogenization may be carried out by using any suitable type
of homogenizer, for example a Silverstone homogenizer, an
ultra-torque homogenizer, colloid mill, sonication, ball milling,
microfluidizer and other homogenization (or emulsification or
dispersion) methods that employ high shear and high mechanical
forces or pressure.
[0059] Once the mixture has been homogenized, the mixture is
separated into a biomass slurry that includes the spent plant
source, and an agent-loaded medium. Separating may be carried by
any suitable method, for example by filtering through a filter or
by centrifugation, decantation or aspiration of the extract phase.
In some embodiments, separating the mixture is carried out by
centrifugation, which may or may not be followed by filtration.
[0060] The plant source may be treated by various pre-treatments
prior to extraction, for example chopping, crushing, blending,
mashing, pulverizing, lyophilizing, drying, heating,
vacuum-treating, freezing, etc. In some embodiments, the plant
source is not treated prior to extraction (namely, used as
such).
[0061] Additional extraction of the lipophilic agent from the
biomass slurry may be carried out by employing additional cycles of
extraction, thereby maximizing the yield obtained from a given
quantity of plant source. Namely, several consecutive extraction
cycles may be carried out on the same plant sample by using fresh
batches of extraction medium in order to maximize the extraction of
the lipophilic agent from the plant source. Thus, in some
embodiments, the process may further comprise:
[0062] (d) mixing the biomass slurry with a second quantity of
extraction medium to obtain a second mixture;
[0063] (e) homogenizing the second mixture; and
[0064] (f) separating the second mixture into biomass slurry and
agent-loaded medium.
[0065] After separation into two phases, the agent-loaded medium
may be further treated by centrifugation to remove solid particles
or liquid droplets having a size of more than 100 nm. Further, the
centrifuged material can be filtered via an adequate filter to
further reduce presence of particles to obtain clear or almost
clear systems. In some embodiments, the desired lipophilic agent
can be separate from the loaded medium by any conventional
technique, such as cooling (freeze drying or spry-draying), or
heating (including vacuum distillation, deodorization etc.), adding
anti-solvents or electrolytes, fillers and others.
[0066] In some embodiments, the step sequence (d)-(f) is repeated
between 1 and 7 times utilizing a given quantity plant source.
[0067] In order to obtain a higher lipophilic agent load in the
medium, the process may be carried out in several cycles of
extraction by using an agent-loaded medium to extract additional
lipophilic agent from a fresh sample of plant source (that was not
previously extracted). Thus, in some embodiments, the process may
further comprise:
[0068] (d') mixing the agent-loaded medium with a second quantity
of the plant source to obtain a second mixture;
[0069] (e') homogenizing the second mixture; and
[0070] (f) separating the second mixture into biomass slurry and
highly agent-loaded medium.
[0071] In some embodiments, the step sequence (d')-(f) is repeated
between 1 and 7 times utilizing the same agent-loaded medium.
[0072] The mixing, homogenizing and separating parameters of steps
(d)-(f) or (d')-(f) may be the same or different than those
describe hereinabove in connection with steps (a)-(c).
[0073] In both process sequences described herein, it is
contemplated by some embodiments that fresh extraction medium and
agent-loaded medium are used in different cycles of the process.
Namely, some of the cycles may be carried out with fresh extraction
medium, while other cycles in the same process sequence may be
carried out with agent-loaded medium.
[0074] The spent biomass can be further processed by any desirable
method to extract further desired components or other lipophilic
agents, by any suitable means or by using a tailored extraction
medium to extract the additional desired component(s).
[0075] Agent-loaded medium quotas from different extraction batches
may be mixed together to obtain a desired concentration of the
lipophilic agent in a final product. Such mixing may be carried out
by any suitable mixing method. The agent-loaded medium can be used
as-is, or can be further formulated by addition of other components
to be loaded into liquid-gel capsules, creams, gels, patches, etc.
as further detailed below.
[0076] In another aspect of this disclosure, there is provided an
extraction medium for extraction of a lipophilic agent from a plant
source containing said lipophilic agent, comprising at least one
oil, at least one hydrophilic surfactant, and at least one
co-surfactant, the microemulsion optionally further comprising at
least one phospholipid, at least one solvent, and/or at least one
co-solvent.
[0077] In a further aspect, this disclosure provides an
agent-loaded medium obtained by the process described herein.
[0078] Yet a further aspect of this disclosure provides an
agent-loaded medium comprising at least 200 ppm (0.02 wt %) of a
desired lipophilic agent, at least one oil, at least one
hydrophilic surfactant, and at least one co-surfactant, the
agent-loaded medium optionally further comprising at least one
solvent, at least one co-solvent, and/or at least one
phospholipid.
[0079] The oil, hydrophilic surfactant, solvent, co-solvent and
phospholipid are selected from those described hereinabove.
[0080] In additional embodiments, each of the mediums described
herein may additionally comprise at least one additive, selected
from antioxidants (tocopherols), oxygen scavengers, preservatives,
membrane-piercing agents, transmembrane penetrating enhancers (e.g.
transcutol, isosorbide, oleic acid, monoglycerides of fatty acids
propylene glycol, maltodextrines, cyclodextrines, etc).
[0081] As noted above, the agent-loaded media may be used as is,
i.e. without addition of other components, as food stuff, food
supplement, nutritional or pharmaceutical compositions.
Alternatively, the agent-loaded media of this disclosure may be
formulated into various formulations, by diluting them with various
diluents or by incorporating them into various other carriers. The
concentrate, as well as the diluted media of this disclosure,
greatly increases the stability of the formulation over time,
reduces the risk of contamination, broadens the scope of its
application to a great variety of concentrations (various dose) and
diluted forms, while permitting the medical professionals the
decision how, when and which formulation to prepare prior to
use.
[0082] The term concentrate denotes a substantially water-free (up
to 10 wt % water), oil-based structured lipid/surfactants system,
in which surfactant tails are solubilized by the lipophilic agent
and the oil facilitating full dilution by a diluent aqueous phase
(are dilatable) at will to form diluted media for any desired
application. In other words, the concentrates are designed for fast
and quantitative dilution in a suitable diluent, for example water
for injection, saline, and aqueous solutions (such as sugar and
sweetener solutions and water-alcohol mixtures), forming the
diluted media, as will now be described. Upon dilution with a
suitable diluent, the concentrate of the invention spontaneously
forms clear homogeneous microemulsions, which are at first
"solvated domains (or clusters) of surfactant" mesophases that upon
minor dilution (ca. 20-30 wt %) form water-in oil nanodroplets; and
upon further dilution transform to bicontinuous mesophases and into
oil-in-water (O/W) nanodroplets, in which the diluent forms the
continuous phase, while the oil phase is in the form of discrete
droplets of nanometric size (i.e. the diluted mediums or diluted
microemulsions). As noted above, the diluted media are formed from
the concentrate spontaneously, namely without the need to apply any
shear, cavitation or homogenization processes.
[0083] In addition to providing flexibility in formulating and
better control of the lipophilic agent administration dose, the
concentrates produced by the process described herein are
substantially free, i.e. devoid, of water. Once water is absent
from the medium, the concentrates lack the environment sustaining
microorganisms growth (e.g. fungi or bacteria), permitting longer
storage without (or with minimal) risk of contamination. Without
wishing to be bound by theory, one of the reasons due to which
almost no bacterial contamination is observed for such concentrates
may be the absence of unbound water, thereby limiting microbial
growth and substantially extending the shelf life of the
agent-loaded medium.
[0084] In some embodiments, the agent-loaded media (i.e.
concentrates) are entirely devoid of water. In other embodiments,
the agent-loaded media (concentrates) contain up to 10 wt %
water.
[0085] The ratio between the concentrate and the diluent depends on
the desired final concentration of lipophilic agent in the
formulation. According to some embodiments, the diluted medium
comprises between about 2 and about 98 wt % of the diluent.
[0086] In another aspect, the present disclosure provides a food,
food supplement, fragrance formulation, pharmaceutical or
nutraceutical composition comprising the agent-loaded media as
described herein.
[0087] In some embodiments, the pharmaceutical composition may
comprise at least one pharmaceutically acceptable carrier. The
"pharmaceutically acceptable carriers" described herein, for
example, vehicles, adjuvants, excipients, or diluents, are
well-known to those who are skilled in the art and are readily
available to the public. It is preferred that the pharmaceutically
acceptable carrier be one which is chemically inert to the active
compounds and one which has no detrimental side effects or toxicity
under the conditions of use.
[0088] The choice of carrier will be determined in part by the
lipophilic agent, as well as by the particular method used to
administer the composition. Accordingly, there is a wide variety of
suitable formulations of the pharmaceutical composition of the
present disclosure.
[0089] As described above, when diluted with an aqueous liquid, a
spontaneous oil-in-water (0/W) microemulsion is formed, in which
the diluent forms the continuous phase, while the oil phase is in
the form of discrete droplets of nanometric size. In some
embodiments, the oil droplets of the diluted medium may have an
average droplet diameter of at less than 100 nanometers.
[0090] In some other embodiments, the droplets size is between
about 10 and 30 nm (nanometers). The droplet size refers to the
arithmetic mean of measured droplets' diameters, wherein the
diameters range .+-.15% from the mean value.
[0091] Further, diluted media (i.e. O/W microemulsions) of the
present disclosure are characterized by a mono-disperse size
distribution of the oil droplets. Namely, the size distribution of
the oil droplets is narrow, without significant divergence from the
mean size value. In some embodiments, the polydispersity index
(PDI) of the distribution of oil droplets is between about 0.03 and
0.1.
[0092] The aqueous diluent may be selected from water, water for
injection, saline, dextrose solution, or a buffer having a pH
between 3 and 9 or any other isotonic solution.
[0093] The lipophilic agent is stably contained (i.e. solubilized)
within the oil droplets, and is controllably released into the
blood stream after administration. Without wishing to be bound by
theory, the agent-oil-surfactant system forms strong molecular
interactions, thus permitting solubilization of the lipophilic
agent within the oil droplets of the microemulsion. Upon high
dilutions, i.e. when introduced into the blood stream, a micellar
system is formed, thereby enabling (because of its dynamic
structure) the release of the lipophilic agent to obtain the
desired effect via simple diffusion.
[0094] The pharmaceutical composition may comprise a variety of
additional components, depending on the administration route and/or
desired properties of the formulation, such as aqueous and
non-aqueous diluents, isotonic sterile injection solutions,
anti-oxidants, buffers, bacteriostats, suspending agents,
solubilizers, thickening agents, gelling agent, emollients,
moisturizers, stabilizers, preservatives, buffers, coloring agents,
a fragrance, absorbers, filters, electrolytes, proteins, chelating
agents, and others.
[0095] In some embodiments, the pharmaceutical composition is in a
form selected from a gel, a lotion, oil, soap, a spray, an
emulsion, a cream, an ointment, capsules, soft-gel capsules,
chewing gum, a patch, or a solution.
[0096] In other embodiments, the formulation may be adapted for
delivery of the lipophilic agent in various routes of
administration, including topical, oral, rectal, vaginal,
transdermal, subcutaneous, intravenous, intramuscular, intranasal,
by inhalation, occularly or parenterally into the circulatory
system of a subject.
[0097] Formulations suitable for oral administration can consist of
(a) liquid solutions, such as an effective amount of the compound,
or composition comprising same, dissolved in diluents, such as
water, saline, or juice (e.g. orange juice); (b) capsules, sachets,
tablets, lozenges, and troches, each containing a predetermined
amount of the active ingredient, as solids or granules; (c)
powders; (d) suspensions in an appropriate liquid; and (e)
concentrates or diluted microemulsions. Liquid formulations may
include diluents, such as water and alcohols, for example, ethanol,
benzyl alcohol, and the polyethylene alcohols, either with or
without the addition of a pharmaceutically acceptable surfactant,
suspending agent, or emulsifying agent. Capsule forms can be of the
ordinary hard- or soft-shelled gelatin type containing, for
example, surfactants, lubricants, and inert fillers, such as
lactose, sucrose, calcium phosphate, and corn starch. Tablet forms
can include one or more of lactose, sucrose, mannitol, corn starch,
potato starch, alginic acid, microcrystalline cellulose, acacia,
gelatin, guar gum, colloidal silicon dioxide, talc, magnesium
stearate, calcium stearate, zinc stearate, stearic acid, and other
excipients, colorants, diluents, buffering agents, disintegrating
agents, moistening agents, preservatives, flavoring agents, and
pharmacologically compatible carriers. Lozenge forms can comprise
the active ingredient in a flavor, usually sucrose and acacia or
tragacanth, as well as pastilles comprising the active formulation
in an inert base, such as gelatin and glycerin, or sucrose and
acacia, emulsions, gels, and the like containing, in addition to
the active formulation, such carriers as are known in the art.
[0098] Another aspect of this disclosure provides an agent-loaded
medium (either in concentrate or diluted form) or a pharmaceutical
composition of this disclosure, for use in treating a condition
selected from pain associated disorders (as an analgesic),
inflammatory disorders and conditions (as anti-inflammatory),
apatite suppression or stimulation (as anoretic or stimulant),
symptoms of vomiting and nausea (as antiemetic), intestine and bowl
disorders, disorders and conditions associated with anxiety (as
anxiolytic), disorders and conditions associated with psychosis (as
antipsychotic), disorders and conditions associated with seizures
and/or convulsions (as antiepileptic or antispasmodic), sleep
disorders and conditions (as anti-insomniac), disorders and
conditions which require treatment by immunosuppression, disorders
and conditions associated with elevated blood glucose levels (as
antidiabetic), disorders and conditions associated with nerve
system degradation (as neuroprotectant), inflammatory skin
disorders and conditions (such as psoriasis), disorders and
conditions associated with artery blockage (as anti-ischemic),
disorders and conditions associated with bacterial infections,
disorders and conditions associated with fungal infections,
proliferative disorders and conditions, disorders and conditions
associated with inhibited bone growth, and others.
[0099] A further aspect, provides a method of treating a subject
suffering from a condition, the method comprising administering to
the subject an effective amount of the agent-loaded medium (either
in concentrate or diluted form) or the pharmaceutical composition
of this disclosure.
[0100] In some embodiments, the condition may be selected from
those described hereinabove.
[0101] The agent-loaded media produced by the process described
herein may be used as such to induce at least one effect, e.g.
therapeutic effect, or may be associated with at least one agent,
e.g. therapeutic agent, which is capable of inducing, enhancing,
arresting or diminishing at least one effect, by way of treatment
or prevention of unwanted conditions or diseases in a subject. The
at least one agent (substance, molecule, element, compound, entity,
or a combination thereof) may be selected amongst therapeutic
agents, i.e. agents capable of inducing or modulating a therapeutic
effect when administered in a therapeutically effective amount, and
non-therapeutic agents, i.e. which by themselves do not induce or
modulate a therapeutic effect hut which may endow the
pharmaceutical composition with a selected desired
characteristic.
[0102] The pharmaceutical compositions of the present disclosure
may be selected to treat, prevent or ameliorate a pathology or
condition. The term treatment or any lingual variation thereof, as
used herein, refers to the administering of a therapeutic amount of
the composition or system described herein, whether in a
concentrate form or in a diluted microemulsion form, which is
effective to ameliorate undesired symptoms associated with a
disease, to prevent the manifestation of such symptoms before they
occur, to slow down the progression of the disease, slow down the
deterioration of symptoms, to enhance the onset of remission
period, slow down the irreversible damage caused in the progressive
chronic stage of the disease, to delay the onset of said
progressive stage, to lessen the severity or cure the disease, to
improve survival rate or more rapid recovery, or to prevent the
disease from occurring or a combination of two or more of the
above.
[0103] As known, the effective amount for purposes herein may be
determined by such considerations as known in the art. The
effective amount is typically determined in appropriately designed
clinical trials (dose range studies) and the person versed in the
art will know how to properly conduct such trials in order to
determine the effective amount. As generally known, the effective
amount depends on a variety of factors including the distribution
profile within the body, a variety of pharmacological parameters
such as half-life in the body, on undesired side effects, if any,
on factors such as age and gender, and others.
[0104] The term subject refers to a mammal, human or non-human.
[0105] The phrases "ranging/ranges between" a first indicate number
and a second indicate number and "ranging/ranges from" a first
indicate number "to" a second indicate number are used herein
interchangeably and are meant to include the first and second
indicated numbers and all the fractional and integral numerals
there between. It should be noted that where various embodiments
are described by using a given range, the range is given as such
merely for convenience and brevity and should not be construed as
an inflexible limitation on the scope of the invention.
Accordingly, the description of a range should be considered to
have specifically disclosed all the possible sub-ranges as well as
individual numerical values within that range.
[0106] As used herein, the term about is meant to encompass
deviation of .+-.10% from the specifically mentioned value of a
parameter, such as temperature, pressure, concentration, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0107] In order to better understand the subject matter that is
disclosed herein and to exemplify how it may be carried out in
practice, embodiments will now be described, by way of non-limiting
example only, with reference to the accompanying drawings, in
which:
[0108] FIGS. 1A-1B show astaxanthin (AX) concentration (FIG. 1A)
and yield of AX extraction (FIG. 1B) in the AX-1 extraction medium
as a function of plant-to-medium ratio (w/w).
[0109] FIGS. 2A-2B show AX concentration (FIG. 2A) and yield of AX
extraction (FIG. 2B) in the AX-1 extraction medium as a function of
extraction duration.
[0110] FIGS. 3A-3B show AX concentration (FIG. 3A) and yield of AX
extraction (FIG. 3B) in the AX-1 extraction medium as a function of
the number of extraction cycles.
[0111] FIGS. 4A-4B show AX concentration (FIG. 4A) and yield of AX
extraction (FIG. 4B) in the AX-1 extraction medium as a function of
the number of extraction cycles from the same biomass.
[0112] FIG. 5 shows the effect of water dilution on unloaded and
AX-loaded extraction medium, as measured by electrical conductivity
tests.
[0113] FIG. 6 shows the effect of water dilution on the viscosity
of unloaded and AX-loaded extraction medium.
[0114] FIG. 7 shows AX-loaded extraction medium, diluted by water
(0-90 wt % water).
[0115] FIGS. 8A-8B show the diffusion coefficients of the
components of the extraction medium (as measured by SD-NMR) for
unloaded and AX-loaded AX-1 medium: full composition (FIG. 8A),
AX-limonene-tween in isolation (FIG. 8B).
[0116] FIGS. 9A-9B show various agent-loaded mediums, concentrates
(FIG. 9A) and diluted by 90 wt % water (FIG. 9B), from left to
right: unloaded AX-1, carrots, turmeric, marigold, beetroot,
nutmeg, tomato, black pepper, allspice and olive leaves.
[0117] FIGS. 10A-10B show the concentration (FIG. 10A) and yield of
extraction (FIG. 10B) of astaxanthin, curcumin and piperine as a
function of the number of extraction cycles.
DETAILED DESCRIPTION OF EMBODIMENTS
[0118] Astaxanthin as a Model Lipophilic Agent
[0119] In the following examples, astaxanthin (AX) was used as a
model lipophilic agent. Astaxanthin is a water-insoluble
antioxidant from the carotenoids group, having the following
structure (Formula I):
##STR00001##
[0120] It is to be understood that various other lipophilic agents
may be extracted from various plant sources by the process and
extraction media disclosed herein, and the extraction of
astaxanthin is brought for exemplifying purposes only. Some
additional exemplary lipophilic agents will be provided below.
[0121] Extraction Medium Composition and Preparation
[0122] As noted above, the extraction media used for the extraction
process are self-assembled systems which are formed in a
spontaneous manner. Therefore, the compositions of the extraction
medium were prepared by simple mixing of ingredients at
15-70.degree. C. An exemplary process for preparing the extraction
medium involves mixing together the oil, the surfactant and the
co-surfactant (and where applicable also a solvent, a co-solvent
and/or a phospholipid) until a homogenous, clear (transparent)
mixture is obtained. In case the surfactants or oil are solid at
room temperature, heating can be applied while mixing to allow full
dissolution and formation of the empty extraction medium.
[0123] The extraction medium is then slowly added to the plant to
allow appropriate wetting and then mixed and homogenized. Another
variation of the process includes adding solid plant parts (for
example leaves or buds) stepwise to the empty (un-loaded)
extraction medium until a homogeneous slurry is obtained.
[0124] Extraction was carried out under heating and inert
atmosphere, thereby solubilizing the desired lipophilic agent into
the extraction medium. The mixture was allowed to settle to the
bottom of the mixing vessel before filtration and/or
centrifugation.
[0125] Table 1 provides details of exemplary formulations used in
the process of the present disclosure.
TABLE-US-00001 TABLE 1 Formulations of extraction medium
Formulation AX-1 Formulation AX-2 Component wt % Component wt % Oil
R-(+)-Limonene 5 MCT 3.5 Hydrophilic Polysorbate 80 45 Tween 80 35
surfactant (Tween 80) Chremophore 42 Co-surfactant Propylene glycol
(PG) 45 PG 13 Solvent Ethanol 5 Ethanol 1.5
[0126] Extraction Process Parameters
[0127] Effect of Plant-to-Medium Ratio
[0128] Haematococcus pluvialis microalgae samples provided by
Algatech (batch number 219) were mixed with AX-1 extraction medium
at a weight ratio of between 1:3 and 1:15 (plant:medium). The
mixture was then homogenized at room temperature using lab
Silverson homogenizer L5M-A for 30 minutes. After homogenization,
each sample was centrifuged at 4000 rpm for 20 minutes or filtered
through cotton wool. Samples were prepared in triplicates.
[0129] Analysis of astaxanthin content in the extracts was carried
out by UV-vis spectrophotometer (max value at 472 nm) or HPLC
vis-a-vis a calibration curve (using the following conditions: C18
column, mobile phase gradient of methanol/water (69/31v/v %) to
100% methanol, flow rate 0.3 ml/min).
[0130] FIGS. 1A-1B show the concentration of astaxanthin (AX) in
the extracts and the extraction yield, respectively, as a function
of the plant-to-medium ratio. Although the nominal concentration
decreases upon increasing the plant:medium ratio (i.e. due to the
dilution effect), the higher the weight ratio between the medium
and the microalgae a higher extraction yield is obtained, reaching
app. 80% extraction yield in a single extraction cycle.
[0131] Effect of Extraction Duration
[0132] Haematococcus pluvialis microalgae samples were mixed with
AX-1 extraction medium at a weight ratio of 1:40. The mixture was
then homogenized at room temperature using Silverson homogenizer
for various periods of time. After homogenization, each sample was
centrifuged at 4000 rpm for 20 minutes or filtered through cotton
wool. Samples were prepared in triplicates.
[0133] Analysis of astaxanthin content in the extracts was carried
out by UV-vis spectrophotometer (max value at 472 nm) or HPLC
vis-a-vis calibration curves. FIGS. 2A-2B show the concentration of
AX in the extracts and the extraction yield, respectively, as a
function of the extraction time.
[0134] As can clearly see from the results, extraction yields of AX
in a single extraction round ranged between 60-80% and up to
.about.0.6 wt % AX-loading in to the medium.
[0135] Multiple-Extractions Processes
[0136] Multiple Cycles Using the Same Quota of Extraction
Medium
[0137] Increasing the concentration of the lipophilic agent, in
this case AX, in the medium was carried out by a multi-extraction
process. For the multi-extraction process a number of extraction
cycles are carried out by using the same quota of medium for
several consecutive extraction cycles, in each cycle a fresh sample
of microalgae is extracted according to the following
procedure.
[0138] A Haematococcus pluvialis microalgae biomass sample was
mixed with AX-1 extraction medium at a weight ratio of 1:10. The
mixture was then homogenized at room temperature using Silverson
homogenizer for 10 minutes. After homogenization, each sample was
centrifuged at 4000 rpm for 20 minutes or filtered through cotton
wool. After separating the AX-loaded medium from the spent biomass,
the AX-loaded medium was weighed and a new sample of microalgae was
added at a weight ratio of 1:15 (plant:medium). Homogenization and
separation were carried out for the new mixture. One additional
cycle of extraction was carried out, amounting to a total of 3
extraction cycles.
[0139] Samples of the medium were taken in between cycles to assess
the effect of the number of cycles on the AX-loading of the
medium.
[0140] Analysis of AX content was done according to the description
hereinabove. FIGS. 3A and 3B show the concentration of AX in the
extracts and the extraction yield, respectively, as a function of
the number of extraction cycles.
[0141] As evident from the results, the AX content in the medium
increases by at least 2.5-folds as a result of the multi-extraction
process. However, as the extraction medium becomes loaded with AX,
the extraction efficiency (i.e. yield) of the medium decreases
compared to the extraction efficiency at the first cycle of
extraction, due to the proximity of the AX content to the maximum
loading capacity of the medium.
[0142] Multiple Cycles Using the Same Biomass of Microalgae
[0143] Similarly, the efficiency of extraction from the plant
source by using multiple cycles of extraction from the same biomass
was tested; namely, the capability to utilized spent biomass for
extraction of additional AX from the same sample.
[0144] A Haematococcus pluvialis microalgae biomass sample was
mixed with AX-1 extraction medium at a weight ratio of 1:10. The
mixture was then homogenized at room temperature using Silverson
homogenizer for 10 minutes. After homogenization, each sample was
centrifuged at 4000 rpm for 20 minutes or filtered through cotton
wool. After separating the AX-loaded medium from the spent biomass,
the spent biomass was weighed and a fresh quota of extraction
medium was added at a weight ratio of 1:15 (plant:medium).
Homogenization and separation were carried out for the new mixture.
One additional cycle of extraction was carried out, amounting to a
total of 3 extraction cycles.
[0145] Samples of the medium were taken in between cycles to assess
the effect of the number of cycles on the AX-loading of the
medium.
[0146] Analysis of AX content was done according to the description
hereinabove. FIGS. 4A and 4B show the concentration of AX in the
extracts and the extraction yield, respectively, as a function of
the number of extraction cycles.
[0147] As can clearly be seen, the extraction of AX from the
microalgae in the first extraction cycle is shown to have
relatively high extraction yield. Namely, in the second and third
cycles of extraction from the same sample of microalgae (i.e.
extraction of the spent biomass by fresh extraction medium quota),
significantly less AX was extracted from the spent biomass. This
attests to the relatively high extraction yield obtained in the
first extraction round (namely when extracting the fresh
microalgae).
[0148] However, as also evident, it is possible to reach about 80%
extraction yield cumulatively by employing multiple extraction
cycles on the same spent biomass.
[0149] Tables 2-3 below provide a comparative summary of the
extraction yields by using the various extraction processes.
TABLE-US-00002 TABLE 2 extraction yields of a single extraction
cycle AX conc. in ME Extraction yield Extraction duration (wt %)
(%) 10 min 0.56 .+-. 0.01 79.5 .+-. 0.8 60 min 0.55 .+-. 0.02 79.5
.+-. 0.8
TABLE-US-00003 TABLE 3 extraction yields of multiple extraction
cycles AX conc. in medium (wt %) Extraction yield (%) Accumulated
1.sup.st cycle 2.sup.nd cycle 3.sup.rd cycle 1.sup.st cycle
2.sup.nd cycle 3.sup.rd cycle yield (%) (1) 0.59 .+-. 0.01 1.10
.+-. 0.08 1.63 .+-. 0.01 76.4 .+-. 5.1 72.4 .+-. 21.4 72.9 .+-.
12.1 73.9 .+-. 12.9 (2) 0.45 .+-. 0.05 0.08 .+-. 0.01 0.06 .+-.
0.04 63.8 .+-. 6.6 30.7 .+-. 03.7 31.8 .+-. 14.8 75.9 .+-. 3.2 (1)
same medium, new biomass (2) same biomass, fresh extraction
medium
[0150] Characterization and Dilatability of the AX-Loaded
Medium
[0151] Effect of Dilution on the Medium's Structure
[0152] As noted above, the media described herein are substantially
devoid of water (i.e. in the form of a concentrate), constituted by
self-assembled oil-solvated clusters or short domains of
surfactants, which differ from the classical reverse micelles. The
concentrates are dilutable by any suitable diluent, for example by
water, to form a diluted delivery system.
[0153] The effect of water dilution on the medium's structure was
investigated by using electrical conductivity tests. Electrical
conductivity measurements were performed at 25.+-.2.degree. C.
using a conductivity meter, type CDM 730 (Mettler Toledo GmbH,
Greifensee, Switzerland). Measurements were made on empty and
AX-loaded samples upon dilution with water up to 95 wt %. No
electrolytes were added to the samples. The conductivity allows to
distinguish between the continuous phase and the inner phase. The
results are shown in FIG. 5.
[0154] As can be seen, the microemulsions undergo 2 phase
transitions upon increasing the amount of diluent. When in
concentrate form, the system is in the form of reverse micelles,
solubilizing the AX within the core of the micelle. When mixed with
small amounts of water, a bicontinuous structure of solvated
(oil-rich) and hydrated (water-rich) domains are formed; upon
further dilution with water, the bicontinuous structure
progressively and continuously transforms into oil-in-water (O/W)
nanodroplets entrapping AX molecules within their oily core (or
within the surfactants tails). As also noted above, the
transformation to O/W microemulsions is spontaneous, i.e. without
the need to employ shear stresses or excessive heating conditions.
Thus, throughout the phase transformations occurring upon dilution,
AX is stabilized and solubilized within the oily phase (as will be
further explained below in connection with SD-NMR analysis).
[0155] In addition, when comparing the unloaded system with the
AX-loaded system, it seems that the presence of AX has no
significant effect on the system's structure and its ability to
undergo the phase transitions.
[0156] Similar results were obtained in viscosity measurements of
unloaded and AX-loaded medium, as shown in FIG. 6. Viscosity
measurements were performed at 25.+-.1.degree. C. on empty and
AX-loaded MEs (Thermo Electron GmbH, Karlsruhe, Germany) using a
cone (60 mm diameter) and glass plate. Shear rates were 0-100
s.sup.-1 in the water.
[0157] Droplet size One of the advantages of the concentrates
described herein is the ability to be diluted at various dilution
ratios, without significantly affecting the formulation's
properties.
[0158] The hydrodynamic radius of the oil droplets was measured at
room temperature by small-angle x-ray scattering (SAXS). Scattering
experiments were performed using CuK.alpha. radiation
(.lamda.=0.154 nm) from Rigaku RA-MicroMax 007 HF X-ray generator
operated at a power rating up to 1.2 kW and generating a
70.times.70 .mu.m.sup.2 focal spot. The osmic CMF12-100CU8 unit
produced a beam size at the sample position of 0.7.times.0.7
mm.sup.2. The scatter radiation passed through a He-filled flight
path and was detected by a Mar345 imagine plate detector from
Marresearch (Nordesledt, Germany). Samples were inserted into 1.5
mm quartz capillaries and scanned for 15 min at T=25.+-.1.degree.
C. The sample to detector distance was calibrated using silver
behenate. Curve fitting of the SAXS profiles was performed using
Origin (MicroCal, MA).
[0159] Average droplet sizes for unloaded and AX-loaded media at
different dilutions (i.e. different water concentrations) are
provided in Table 4.
TABLE-US-00004 TABLE 4 Average droplet size values at different
dilutions Water content Unloaded system AX-loaded (wt %) (nm) (nm)
0 12.57 15.65 10 7.34 8.89 30 8.51 9.16 50 9.59 10.60 90 5.93
6.95
[0160] As clearly evident from Table 4, the droplet sizes of the
empty system are smaller than those measured for the loaded systems
indicating that AX is located within the core/interface of the drop
increasing its size (see also SD-NMR analysis below).
[0161] Further, as seen in FIG. 7, the very small droplet size that
characterizes the media described herein (typically have an average
droplet diameter of less than 20 nm) enables obtaining clear and
transparent microemulsions for prolonged periods of time, without
phase separation. The transparency also enables detection of
undesired contaminants, thereby allowing the user to easily
identify in a visual manner contaminated formulations that are
unsuitable for use.
[0162] Self-Diffusion NMR (SD-NMR)
[0163] In order to determine the structure of the oil droplets (or
micelles) of the medium, self-diffusion NMR analysis was carried
out. SD-NMR is able to locate each component within the medium via
measurements of its diffusion coefficient. Rapid diffusion
(>100.times.10.sup.-12 m.sup.2s.sup.-1) is characteristic of
small molecules, free in solution, while slow diffusion
coefficients (<0.1.times.10.sup.-12 m.sup.2s.sup.-1) suggest low
mobility of macromolecules or bound/aggregated molecules.
[0164] NMR measurements were performed with a Bruker AVII 500
spectrometer equipped with GREAT 1/10 gradients, a 5 mm BBO and a 5
mm BBI probe, both with a z-gradient coil and with a maximum
gradient strength of 0.509 and 0.544 Tm.sup.-1, respectively.
Diffusion was measured using an asymmetric bipolar longitudinal
eddy-current delay (bpLED) experiment, or an asymmetric bipolar
stimulated echo (known as one-shot) experiment with convection
compensation and an asymmetry factor of 20%, ramping the strongest
gradient from 2% to 95% of maximum strength in 32 steps. The
spectrum was processed with the Bruker TOPSPIN software. NMR
spectra were recorded at 25.+-.0.2.degree. C. The components were
identified by their chemical shift in 1H NMR.
[0165] Tables 5-1 and 5-2 shows the diffusion coefficients (Dx,
m.sup.2/sec) of the unloaded and AX-loaded medium (with 0.5 wt % of
AX), respectively, at various water dilutions. The results are also
graphically presented in FIGS. 8A-8B.
TABLE-US-00005 TABLE 5-1 Diffusion coefficients (m.sup.2/sec), as
measured by SD-NMR, unloaded extraction medium Water content (wt %)
Tween 80 PG R-(+)-limonene EtOH D.sub.2O 0 4.6 .times. 10.sup.-12
4.5 .times. 10.sup.-11 5.66 .times. 10.sup.-11 4.58 .times.
10.sup.-11 -- 10 3.3 .times. 10.sup.-12 4.74 .times. 10.sup.-11
3.33 .times. 10.sup.-11 4.85 .times. 10.sup.-11 3.3 .times.
10.sup.-11 20 1.5 .times. 10.sup.-12 6.15 .times. 10.sup.-11 1.36
.times. 10.sup.-11 6.17 .times. 10.sup.-11 1.35 .times. 10.sup.-11
30 .sup. 6 .times. 10.sup.-13 8.55 .times. 10.sup.-11 4.3 .times.
10.sup.-12 8.67 .times. 10.sup.-11 2.64 .times. 10.sup.-10 40 .sup.
5 .times. 10.sup.-13 1.24 .times. 10.sup.-10 1.5 .times. 10.sup.-12
1.25 .times. 10.sup.-10 3.88 .times. 10.sup.-10 50 .sup. 9 .times.
10.sup.-13 1.68 .times. 10.sup.-10 1.5 .times. 10.sup.-12 1.65
.times. 10.sup.-10 5.0 .times. 10.sup.-10 60 2.2 .times. 10.sup.-12
2.34 .times. 10.sup.-10 3.3 .times. 10.sup.-12 2.37 .times.
10.sup.-10 6.34 .times. 10.sup.-10 70 5.7 .times. 10.sup.-12 3.19
.times. 10.sup.-10 5.9 .times. 10.sup.-12 3.3 .times. 10.sup.-10
9.1 .times. 10.sup.-10 80 1.09 .times. 10.sup.-11 4.42 .times.
10.sup.-10 1.15 .times. 10.sup.-11 4.82 .times. 10.sup.-10 1.13
.times. 10.sup.-9 90 2.06 .times. 10.sup.-11 6.03 .times.
10.sup.-10 2.14 .times. 10.sup.-11 5.82 .times. 10.sup.-10 1.45
.times. 10.sup.-09
TABLE-US-00006 TABLE 5-2 Diffusion coefficients (m.sup.2/sec), as
measured by SD-NMR, 0.5 wt % AX-loaded medium Water content (wt %)
Tween 80 PG R-(+)-limonene EtOH D.sub.2O AX 0 4.5 .times.
10.sup.-12 4.43 .times. 10.sup.-11 5.46 .times. 10.sup.-11 4.13
.times. 10.sup.-11 -- 4.7 .times. 10.sup.-12 10 3.5 .times.
10.sup.-12 4.78 .times. 10.sup.-11 3.09 .times. 10.sup.-11 4.66
.times. 10.sup.-11 3.1 .times. 10.sup.-11 .sup. 3 .times.
10.sup.-12 20 2.9 .times. 10.sup.-12 4.86 .times. 10.sup.-11 2.36
.times. 10.sup.-11 4.78 .times. 10.sup.-11 2.84 .times. 10.sup.-11
1.4 .times. 10.sup.-12 30 .sup. 6 .times. 10.sup.-13 8.69 .times.
10.sup.-11 3.2 .times. 10.sup.-12 8.67 .times. 10.sup.-11 3.2
.times. 10.sup.-12 .sup. 3 .times. 10.sup.-13 40 .sup. 4 .times.
10.sup.-13 1.23 .times. 10.sup.-10 1.4 .times. 10.sup.-12 1.2
.times. 10.sup.-10 1.3 .times. 10.sup.-12 .sup. 3 .times.
10.sup.-13 50 .sup. 9 .times. 10.sup.-13 1.75 .times. 10.sup.-10
1.4 .times. 10.sup.-12 1.7 .times. 10.sup.-10 2.69 .times.
10.sup.-11 .sup. 7 .times. 10.sup.-13 60 2.2 .times. 10.sup.-12
2.41 .times. 10.sup.-10 3.1 .times. 10.sup.-12 2.33 .times.
10.sup.-10 7.96 .times. 10.sup.-10 1.4 .times. 10.sup.-12 70 5.3
.times. 10.sup.-12 3.35 .times. 10.sup.-10 5.7 .times. 10.sup.-12
3.32 .times. 10.sup.-10 9.1 .times. 10.sup.-10 4.8 .times.
10.sup.-12 80 1.05 .times. 10.sup.-11 4.67 .times. 10.sup.-10 1.10
.times. 10.sup.-11 4.67 .times. 10.sup.-10 1.16 .times. 10.sup.-9
1.12 .times. 10.sup.-11 90 1.91 .times. 10.sup.-11 6.03 .times.
10.sup.-10 1.91 .times. 10.sup.-11 5.89 .times. 10.sup.-10 1.48
.times. 10.sup.-09
[0166] As can be seen from Tables 5-1 and 5-2, the diffusion
coefficient of AX is similar to that of the surfactants (Tween 80
and R-(+)-limonene). These results indicate that the AX is located
within the core and at the interface of the swollen micelle. As
also evident from the results, AX solubilization causes the binding
of water molecules through interaction with the surfactant. This
suggests that all of the AX in the media is contained within the
oil droplet, and it is likely that no free AX is within the aqueous
continuous phase, attesting to the ability of the medium to contain
and stabilize AX.
[0167] Further, at dilutions of .about.30-50% water, AX binds water
through interaction with the surfactant, as evident by the low
diffusion coefficients of D.sub.2O in the AX-loaded medium compared
to the unladed system. This means that astaxanthin has no direct
interaction with the water, however, it affects the water mobility
that is induced by the surfactant.
[0168] Other Lipophilic Agents
[0169] Astaxanthin was demonstrated above as a model lipophilic
agent for extraction processes described herein. However, the
process may be used to extract a variety of lipophilic agents from
a variety from natural sources.
[0170] A number of plant sources containing active molecules were
chosen to show the high effectiveness of the extraction medium for
the extraction of various active molecules: piperine (extracted
from black pepper corns), oleuropein (extracted from olive leaves),
trimyristin (extracted from nutmeg), eugenol (extracted from
allspice corns), curcumin (extracted from turmeric root), carotene
(extracted from baby carrots), lycopene (extracted from dried
tomatoes and lycopene rich cherry tomatoes), lutein (extracted from
marigold flowers), and betain and anthocyanins (extracted from
beetroot).
[0171] According to the raw plant, pretreatment was optionally
carried out. Olive leaves, nutmeg (grounded), and turmeric
(grounded) were used as received. Black pepper and allspice were
pounded with pestle and mortar and sieved. Beetroot, dried tomatoes
and baby carrots were finely chopped and heated at vacuum oven for
1.5 hours at 60.degree. C. Marigold flowers were washed and dried,
and petals were separated and heated under vacuum for 1.5 hours at
60.degree. C. Lycopene rich cherry tomatoes were mashed in a
blender; half of the mashed tomatoes were centrifuged twice to
remove most of the water. The other half was lyophilized for 20
hours.
[0172] Extraction was carried out as follow: plants samples were
weighted, and then AX-1 extraction medium was weighted into the
same flask. The ratios between the plant and the extraction medium
were determined based on the plant and were within a range of 1:1
and 1:10. A Silverson homogenizer was used for homogenization for
30 min at room temperature (25-28.degree. C.). At the end of the
extraction, the slurry was centrifuged for 20 min for separating
the loaded medium from the spent biomass. The loaded medium was
filtered and kept in the fridge until been analyzed.
[0173] For the extraction of piperine and curcumin another series
of 3 cycles of extractions was accomplished, using new plant source
and loaded-ME at each cycle.
[0174] Droplet Size Measurements
[0175] The loaded-medium samples were diluted by 90 wt % water and
droplet size was measured with DLS.
[0176] Table 6 presents the droplet size of the extracts from
different plant sources as well as the polydispersity index. FIGS.
9A and 9B show the concentrates and diluted mediums,
respectively.
TABLE-US-00007 TABLE 6 Droplet size and polydispersity index of
agent-loaded mediums, 90 wt % water Plant source Drop size [nm] PDI
Allspice NA NA Black pepper 12.05 .+-. 0.45 0.15 .+-. 0.01 Nutmeg
14.92 .+-. 0.32 0.27 .+-. 0.32 Olive leaves NA NA Turmeric 11.84
.+-. 0.19 0.21 .+-. 0.01 Tomatoes 12.03 .+-. 0.26 0.14 .+-. 0.03
Carrots 11.55 .+-. 0.21 0.18 .+-. 0.02 Marigold flower 11.57 .+-.
0.01 0.17 .+-. 0.01 Beetroot 18.33 .+-. 0.37 0.36 .+-. 0.01 Empty
system 11.24 .+-. 0.26 0.115 .+-. 0.024
[0177] Concentration of Active Molecules in the Medium and Yield of
the Extraction
[0178] One Step Extraction
[0179] Extraction products from black pepper, turmeric, tomato
paste, and lyophilized tomato were diluted with distilled water or
organic solvents (ethanol or acetone) at 10.sup.2-10.sup.3 order of
magnitude. UV-visible spectrum of the dilutions were recorded
against suitable blank and absorption at the chosen wavelength was
taken for the determination of the component in the extract. A
spectrum of standards was recorded for each agent, from which the
wavelength at the maximum was chosen as the wavelength at which
calibration curve was constructed based on Beer-Lambert law.
Further calculation based on reported data about plant capacity of
each nutraceutical were carried out to determine the yield of the
extraction. Table 7 details the concentration of the active
molecules in the agent-loaded mediums and the yield of the
extraction.
TABLE-US-00008 TABLE 7 The concentration of the active molecules
and yield of the extraction after one cycle Concentration Yield of
Active .lamda..sub.max Concentration in medium extraction molecule
Source [nm] in plant source [mg/g] [%] Piperine Black pepper 310
5-9% [2] 12.48 69.3-89.2 (grounded) Curcumin Turmeric 424
0.58-3.14% [3] 2.02 32.2-50.5 (grounded) Lycopene Tomato paste 480
340 ppm [4] 0.04 57.9 Lyophilized 480 900-1200 ppm [5] 0.05
40.6-58.1 tomatoes Yield determined according to range of
concentrations of component in the plant
[0180] Multi-Step Extraction
[0181] Extraction products from black pepper and turmeric were
diluted with ethanol or acetone at 10.sup.3-10.sup.4 order of
magnitude. Analysis was the same as in case of one step extraction.
FIG. 10A shows the concentrations of curcumin and piperine, as
compared to astaxanthin, in the medium after one, two and three
cycles. Linear fit was plotted for each component. FIG. 10B shows
the yield of the extraction at each of the three cycles for
astaxanthin, curcumin and piperine.
[0182] As clearly evident, the extraction mediums and process
described herein demonstrate the ability to extract various
molecules from their natural source, which appears in a variety of
forms. As also evident, for the same extraction medium formulation,
different concentrations and yields were achieved for each
extracted molecule, suggesting that selectivity of extraction may
be controlled by tailoring the composition of the microemulsion to
the desired molecule to be extracted.
[0183] Further exemplary target molecules which were extracted by
AX-1 extraction medium formulation were rosmanol acid (extracted
from rosemary leaves), cinamaldehyde (extracted from cinnamon
hark), chlorogenic acid (extracted from green coffee beans), and
omega 3 fatty acid (extracted from chia seeds).
[0184] Cinnamon and chia seeds were used as received. Green coffee
beans were ground and pounded by pestle and mortar. Rosemary was
either chopped or heated for 13 min before the extraction.
[0185] Extraction was carried out as detailed above. Initial
characterization results are provided in Table 8.
TABLE-US-00009 TABLE 8 Characterization of mediums loaded with the
active molecules Viscosity of Drop size concentrate Active molecule
[nm] [.mu.S/cm] Rosmarinic acid 21.41 (.+-.0.36) 0.129 (.+-.0.013)
Cinamaldehyde 17.87 (.+-.0.97) 0.141 (.+-.0.002) Chlorogenic acid
11.45 (.+-.0.77) 0.093 (.+-.0.009) Linolenic acid 26.05 (.+-.0.97)
NA
* * * * *