U.S. patent application number 16/626943 was filed with the patent office on 2021-10-28 for dihydrofuran chalcone compound and preparation method thereof.
This patent application is currently assigned to SOUTH CHINA BOTANICAL GARDEN, CHINESE ACADEMY OF SCIENCES. The applicant listed for this patent is SOUTH CHINA BOTANICAL GARDEN, CHINESE ACADEMY OF SCIENCES. Invention is credited to Yueming JIANG, Bao YANG.
Application Number | 20210332022 16/626943 |
Document ID | / |
Family ID | 1000005765086 |
Filed Date | 2021-10-28 |
United States Patent
Application |
20210332022 |
Kind Code |
A1 |
YANG; Bao ; et al. |
October 28, 2021 |
DIHYDROFURAN CHALCONE COMPOUND AND PREPARATION METHOD THEREOF
Abstract
A method for preparing a dihydrofuran chalcone includes the
following steps: subjecting a Morus alba leaf to extraction with an
aqueous solution of methanol or ethanol having a volume fraction of
40%-100%, concentrating an extract to remove methanol or ethanol
and dissolving in water, subjecting to extraction with petroleum
ether and ethyl acetate successively, and concentrating an ethyl
acetate extract to obtain a paste; chromatographing the paste over
a silica gel column using chloroform-methanol, collecting an eluate
where the volume ratio of chloroform-methanol is 95/5;
chromatographing the eluate over a reversed-phase column using
acetonitrile-water, collecting an eluate where the volume ratio of
acetonitrile-water is 30/70, and thereby the dihydrofuran chalcone
is obtained.
Inventors: |
YANG; Bao; (Guangzhou,
CN) ; JIANG; Yueming; (Guangzhou, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOUTH CHINA BOTANICAL GARDEN, CHINESE ACADEMY OF SCIENCES |
Guangzhou |
|
CN |
|
|
Assignee: |
SOUTH CHINA BOTANICAL GARDEN,
CHINESE ACADEMY OF SCIENCES
Guangzhou
CN
|
Family ID: |
1000005765086 |
Appl. No.: |
16/626943 |
Filed: |
December 18, 2018 |
PCT Filed: |
December 18, 2018 |
PCT NO: |
PCT/CN2018/121636 |
371 Date: |
December 27, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07D 307/80
20130101 |
International
Class: |
C07D 307/80 20060101
C07D307/80 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 1, 2018 |
CN |
201811296972.4 |
Claims
1. (canceled)
2. A method for preparing dihydrofuran chalcone, comprising:
isolating the dihydrofuran chalcone from a Morus alba leaf, wherein
the dihydrofuran chalcone has a structure according to formula (I):
##STR00003##
3. The method according to claim 2, wherein, the step of isolating
the dihydrofuran chalcone from the Morus alba leaf comprises the
following steps: subjecting the Morus alba leaf to a first
extraction with an aqueous solution of methanol or ethanol having a
volume fraction of 40%-100% to obtain an extract, concentrating the
extract to remove the methanol or ethanol to obtained a
concentrated extract and dissolving the concentrated extract in
water to obtain a dissolved extract, subjecting the dissolved
extract to a second extraction with petroleum ether and ethyl
acetate successively to obtain an ethyl acetate extract, and
concentrating the ethyl acetate extract to obtain a paste;
chromatographing the paste over a silica gel column by a first
gradient elution using chloroform-methanol with a volume ratio
ranging from 100/0 to 60/40, collecting an first eluate wherein the
volume ratio of chloroform-methanol is 95/5; chromatographing the
first eluate over a reversed-phase column by a second gradient
elution using acetonitrile-water with a volume ratio ranging from
5/95 to 100/0, collecting an second eluate wherein the volume ratio
of acetonitrile-water is 30/70 to obtain the dihydrofuran
chalcone.
4. The method according to claim 3, wherein, the Morus alba leaf is
provided as Morus alba leaf powders, and the Morus alba leaf
powders are obtained by drying a fresh Morus alba leaf and
pulverizing into powders.
5. The method according to claim 3, wherein, in the step of
subjecting the Morus alba leaf to the first extraction with the
aqueous solution of methanol or ethanol having the volume fraction
of 40%-100%, the aqueous solution of methanol or ethanol is used
according to a proportion of 5 to 20 mL/g based on the Morus alba
leaf, an extraction temperature of the first extraction ranges from
25.degree. C. to 70.degree. C., and an extraction time of the first
extraction ranges from 1 hour to 72 hours.
6. The method according to claim 3, wherein, in the step of
concentrating the extract to remove the methanol or ethanol to
obtained the concentrated extract and dissolving the concentrated
extract in water, the extract is concentrated at 40.degree. C. to
80.degree. C. to remove the methanol or ethanol, and the
concentrated extract is dissolved by adding water wherein a volume
of the water is 1 to 5 times the concentrated extract.
7. The method according to claim 3, wherein, in the step of
subjecting the dissolved extract to the second extraction with the
petroleum ether and ethyl acetate successively to obtain the ethyl
acetate extract, the second extraction is performed first with the
petroleum ether for 3 to 12 times and then with the ethyl acetate
for 3 to 12 times.
8-9. (canceled)
Description
TECHNICAL FIELD
[0001] The present invention relates to the field of natural
product chemistry, particularly relates to a dihydrofuran chalcone
compound and a preparation method thereof.
BACKGROUND
[0002] Morus alba is an evergreen macrophanerophyte in the family
Moraceae, widely planted in tropical and subtropical regions. Morus
alba fruits are sweet and delicious, with high nutritional value
and health-care functions, have the effects of treating canities
and anti-inflammatory, and thus are well received by consumers.
Morus alba leaves, identified as a new vegetable food material,
have a fresh taste and have gradually been accepted by consumers.
Studies have found that Morus alba leaves are rich in flavonoids
and have biological activities such as anti-oxidation, anti-cancer
and immunoregulation. However, there are few studies on the active
ingredients of Morus alba leaves, and the composition of related
active substances remains to be studied.
SUMMARY
[0003] One object of the present invention is to provide a
dihydrofuran chalcone and a preparation method thereof.
[0004] The dihydrofuran chalcone of the present invention is
isolated from a Morus alba leaf, and has a structure according to
formula (I):
##STR00001##
[0005] A preparation method of the dihydrofuran chalcone, comprises
the following steps:
[0006] subjecting a Morus alba leaf to extraction with an aqueous
solution of methanol or ethanol having a volume fraction of
40%-100%, concentrating an extract to remove methanol or ethanol
and dissolving in water, subjecting to extraction with petroleum
ether and ethyl acetate successively, and concentrating an ethyl
acetate extract to obtain a paste; chromatographing the paste over
a silica gel column by gradient elution using chloroform-methanol
with a volume ratio of 100/0 to 60/40, collecting an eluate where
the volume ratio of chloroform-methanol is 95/5; chromatographing
the eluate over a reversed-phase column by gradient elution using
acetonitrile-water with a volume ratio of 5/95 to 100/0, collecting
an eluate where the volume ratio of acetonitrile-water is 30/70,
and thereby the dihydrofuran chalcone is obtained.
[0007] The Morus alba leaf is provided as Morus alba leaf powders,
which are obtained by drying a fresh Morus alba leaf and
pulverizing into powders.
[0008] In the step of subjecting the Morus alba leaf to extraction
with the aqueous solution of methanol or ethanol having the volume
fraction of 40%-100%, the aqueous solution of methanol or ethanol
is used according to a proportion of 5 to 20 mL/g Morus alba leaf
(i.e., 5 to 20 mL of the aqueous solution of methanol or ethanol is
used for one gram of the Morus alba leaf), an extraction
temperature is 25.degree. C. to 70.degree. C., and an extraction
time is 1 to 72 hours.
[0009] In the step of concentrating the extract to remove methanol
or ethanol and dissolving in water, the extract is concentrated at
40.degree. C. to 80.degree. C. to remove methanol or ethanol, and
dissolved by adding water wherein a volume of the water is 1 to 5
times that of the concentrated extract.
[0010] The step of subjecting to extraction with petroleum ether
and ethyl acetate successively, comprises first extracting with
petroleum ether for 3 to 12 times and then extracting with ethyl
acetate for 3 to 12 times.
[0011] The present invention also provides an antioxidant skin care
product, medicine or health product, which comprises the
dihydrofuran chalcone as an active ingredient.
[0012] It has been confirmed by the present invention that, the
dihydrofuran chalcone has a high free radical scavenging capacity.
An IC.sub.50 value of the compound against DPPH radicals is 32.7
.mu.M, which is significantly lower than the IC.sub.50 value of
positive control vitamin C (Vc) which is 100 .mu.M, indicating that
the dihydrofuran chalcone of the present invention has an excellent
antioxidant activity, and thus can be used to prepare antioxidant
skin care products, medicines or health products.
[0013] Compared with the prior art, the present invention has the
following advantages:
[0014] The present invention realizes the preparation of
dihydrofuran chalcone by isolating the compound from Morus alba
leaves, with a yield of 23 to 157 mg/kg (and a purity of 85% to
95%). The present invention is of great significance for promoting
the deep processing and utilization of Morus alba leaves, enhancing
the added value of Morus alba leaves products, and promoting the
sustainable development of the industry. Furthermore, the invention
also provides a novel method for preparing dihydrofuran
chalcone.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0015] The following embodiments are further illustrations of the
present invention, but not limitation of the present invention.
Embodiment 1
[0016] 1. Preparation and Isolation of Dihydrofuran Chalcone
[0017] (1) Materials: Fresh Morus alba leaves were collected and
washed with water.
[0018] (2) Drying and pulverizing: The Morus alba leaves were dried
in the sun or in an oven, and then pulverized into powders with a
pulverizer.
[0019] (3) Extraction: An aqueous solution of methanol (40% v/v)
was added to the Morus alba leave powders according to a proportion
of 5 mL/g Morus alba leaf powders (i.e., 5 mL of the aqueous
solution of methanol was used for one gram of the Morus alba leaf
powders) to allow extraction at 25.degree. C. for 1 hour. The
mixture was then subjected to a filtration process and the filtrate
was collected.
[0020] (4) Organic solvent fractionation: The filtrate was
concentrated at 40.degree. C. to remove methanol and give a
concentrated solution, followed by the addition of water having the
same volume of the concentrated solution. The resulting solution
was then successively subjected to extraction with petroleum ether
(having the same volume of the resulting solution) for three times
and with ethyl acetate (having the same volume of the resulting
solution) for three times. The ethyl acetate extracts were
concentrated to give a paste which would be subjected to subsequent
purification.
[0021] (5) The paste, obtained by concentrating the ethyl acetate
extracts, was chromatographed over a silica gel column (100-200
mesh) by gradient elution using chloroform-methanol with a volume
ratio of 100/0 to 60/40, and an eluate was collected where the
volume ratio of chloroform-methanol was 95/5. The eluate was then
chromatographed over a C18 reversed-phase column by gradient
elution using acetonitrile-water with a volume ratio of 5/95 to
100/0, and an eluate was collected where the volume ratio of
acetonitrile-water was 30/70. The eluate was then dried by
evaporation concentration at 60.degree. C. to give a compound 1,
dihydrofuran chalcone.
[0022] By using this method, a yield of the dihydrofuran chalcone
was 23 to 49 mg/kg, with a purity of 85% to 95%.
[0023] 2. Structure Identification of the Compound 1
[0024] The compound 1 was easily soluble in methanol. Mass
spectrometry results showed that the molecular weight of this
compound was 356. .sup.1H NMR (500 MHz, CD.sub.3OD) and .sup.13C
NMR (125 MHz, CD.sub.3OD) data were as listed in Table 1.
TABLE-US-00001 TABLE 1 .sup.13C and .sup.1H chemical shifts of
compound 1 Position .sup.1H .sup.13C 1 115.1 2 160.5 3 6.35 103.7 4
161.1 5 6.37 109.2 6 7.52 132.4 1' 114.7 2' 168.1 3' 114.6 4' 162.1
5' 6.37 109.0 6' 7.89 133.1 1'' 3.13 27.9 2'' 4.74 92.6 3'' 72.2
4'' 1.28 25.1 5'' 1.24 25.3 .alpha. 7.73 117.4 .beta. 8.09 142.1
Carbonyl group 194.1
[0025] In view of the above, the compound 1 was identified to have
a structure according to formula (I) and named as dihydrofuran
chalcone, easily soluble in methanol.
##STR00002##
Embodiment 2
[0026] (1) Materials: Fresh Morus alba leaves were collected and
washed with water.
[0027] (2) Drying and pulverizing: The Morus alba leaves were dried
in the sun or in an oven, and then pulverized into powders with a
pulverizer.
[0028] (3) Extraction: An aqueous solution of methanol (100% v/v,
i.e., pure methanol) was added to the Morus alba leave powders
according to a proportion of 20 mL/g Morus alba leaf powders (i.e.,
20 mL of the aqueous solution of methanol was used for one gram of
the Morus alba leaf powders) to allow extraction at 60.degree. C.
for 72 hours. The mixture was then subjected to a filtration
process and the filtrate was collected.
[0029] (4) Organic solvent fractionation: The filtrate was
concentrated at 60.degree. C. to remove methanol and give a
concentrated solution, followed by the addition of water having a
volume five times that of the concentrated solution. The resulting
solution was then successively subjected to extraction with
petroleum ether (having the same volume of the resulting solution)
for twelve times and with ethyl acetate (having the same volume of
the resulting solution) for twelve times. The ethyl acetate
extracts were concentrated to give a paste which would be subjected
to subsequent purification.
[0030] The purification step was identical to that in the
embodiment 1 to give the compound 1 which was identified to be
dihydrofuran chalcone.
[0031] By using this method, a yield of the dihydrofuran chalcone
was 115 to 157 mg/kg, with a purity of 85% to 95%.
Embodiment 3
[0032] (1) Materials: Fresh Morus alba leaves were collected and
washed with water.
[0033] (2) Drying and pulverizing: The Morus alba leaves were dried
in the sun or in an oven, and then pulverized into powders with a
pulverizer.
[0034] (3) Extraction: An aqueous solution of ethanol (40% v/v) was
added to the Morus alba leave powders according to a proportion of
20 mL/g Morus alba leaf powders (i.e., 20 mL of the aqueous
solution of ethanol was used for one gram of the Morus alba leaf
powders) to allow extraction at 55.degree. C. for 24 hours. The
mixture was then subjected to a filtration process and the filtrate
was collected.
[0035] (4) Organic solvent fractionation: The filtrate was
concentrated at 60.degree. C. to remove ethanol and give a
concentrated solution, followed by the addition of water having a
volume three times that of the concentrated solution. The resulting
solution was then successively subjected to extraction with
petroleum ether (having the same volume of the resulting solution)
for six times and with ethyl acetate (having the same volume of the
resulting solution) for six times. The ethyl acetate extracts were
concentrated to give a paste which would be subjected to subsequent
purification.
[0036] The purification step was identical to that in the
embodiment 1 to give the compound 1 which was identified to be
dihydrofuran chalcone.
[0037] By using this method, a yield of the dihydrofuran chalcone
was 55 to 104 mg/kg, with a purity of 85% to 95%.
Embodiment 4
[0038] (1) Materials: Fresh Morus alba leaves were collected and
washed with water.
[0039] (2) Drying and pulverizing: The Morus alba leaves were dried
in the sun or in an oven, and then pulverized into powders with a
pulverizer.
[0040] (3) Extraction: An aqueous solution of ethanol (100% v/v,
i.e., pure ethanol) was added to the Morus alba leave powders
according to a proportion of 5 mL/g Morus alba leaf powders (i.e.,
5 mL of the aqueous solution of ethanol was used for one gram of
the Morus alba leaf powders) to allow extraction at 70.degree. C.
for 48 hours. The mixture was then subjected to a filtration
process and the filtrate was collected.
[0041] (4) Organic solvent fractionation: The filtrate was
concentrated at 80.degree. C. to remove ethanol and give a
concentrated solution, followed by the addition of water having the
same volume of the concentrated solution. The resulting solution
was then successively subjected to extraction with petroleum ether
(having the same volume of the resulting solution) for six times
and with ethyl acetate (having the same volume of the resulting
solution) for six times. The ethyl acetate extracts were
concentrated to give a paste which would be subjected to subsequent
purification.
[0042] The purification step was identical to that in the
embodiment 1 to give the compound 1 which was identified to be
dihydrofuran chalcone.
[0043] By using this method, a yield of the dihydrofuran chalcone
was 48 to 96 mg/kg, with a purity of 85% to 95%.
Embodiment 5
[0044] DPPH is a stable free radical. When a free radical scavenger
is present, light absorption of DPPH will be reduced when the
single electron is scavenged, which allows to evaluate free radical
scavenging ability of the substance and accordingly determine
antioxidant ability thereof. The DPPH radical scavenging ability of
the dihydrofuran chalcone was measured through the DPPH radical
scavenging assay, so as to evaluate the antioxidant ability of the
compound. The assay comprised the following steps:
[0045] 1,1-Diphenyl-2-picrylhydrazyl (DPPH) was dissolved in
absolute ethanol to obtain a solution with a concentration of 0.2
mM. The dihydrofuran chalcone was dissolved in absolute ethanol. 80
.mu.L of the ethanol solution of dihydrofuran chalcone and 160
.mu.L of the 0.2 mM DPPH ethanol solution were mixed and the
mixture was placed in dark at room temperature for 30 minutes.
Then, light absorbance at 517 nm was measured using a microplate
reader (SpectraMax 190, Molecular Devices, USA), and Vc was
employed as a positive control. Results showed that, the
dihydrofuran chalcone had an IC.sub.50 value of 32.7 .mu.M against
DPPH radicals, while Vc had an IC.sub.50 value of 100 .mu.M against
DPPH radicals, indicating that the dihydrofuran chalcone of the
present invention had an excellent antioxidant ability
significantly better than that of the positive control Vc, and thus
could be used to prepare antioxidant skin care products, medicines
or health products.
[0046] The above descriptions are only preferred embodiments of the
present invention. It should be noted that the above preferred
embodiments should not be regarded as a limitation to the present
invention, and the scope of the present invention shall be defined
by the claims. For those of ordinary skill in the art, without
departing from the spirit and scope of the present invention,
several improvements and modifications can be made, which should
also be within the scope of the present invention.
* * * * *