• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.179-184
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• 1997

To search for useful antioxidants from plant materials, we investigated the antioxidative activity in the methanol extracts of 30 Chinese medicinal plants using DPPH method. The highest activity $(RC_{50}:\;12\;{\mu}g)$ was showed in the methanol extract of Rosa rugosa, followed by Potentilla fruticosa $(14\;{\mu}g)$, P. fragarioides $(16\;{\mu}g)$. And Geum aleppicum $(18\;{\mu}g)$. From the leaves of R. rugosa, two antioxidative compounds were isolated by a bioassay guided purification and identified as isoquercitrin and ${\beta}-glucogallin$ on the basis of $^1H-,\;^{13}C-\;NMR$, and FAB-MS data. ${\beta}-Glucogallin$ is the first report in this plant. The DPPH radical scavenging activity of ${\beta}-glucogallin\;(RC_{50}:\;8.5\;{\mu}g)$ was more effective than those of ${\alpha}-tocopherol\;(12\;{\mu}g)$ and BHA $(14\;{\mu}g)$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.517-524
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• 2011

Eleven polyphenolic compounds, including procatechuic and chlorogenic acids, (+)-dihydroquercetin, rutin, isoquercitrin, quercitrin, (+)-dihydrokaempferol, trans-resveratrol, moracin, quercetin and 4-prenylmoracin were isolated and purified from the methanolic extract of defatted mulberry seed residue by a series of column chromatography including silica gel, Sephadex LH-20, and ODS-A, and their chemical structures were identified by spectral analysis. The antioxidant activities of the eleven isolated polyphenolic compounds were measured spectrophotometrically using DPPH radical. Among the eleven polyphenolic compounds tested, rutin ($IC_{50}=20.2\;{\mu}M$), isoquercitrin ($IC_{50}=22.5\;{\mu}M$), quercitrin ($IC_{50}=24.6\;{\mu}M$), quercetin ($IC_{50}=27.8\;{\mu}M$), (+)-dihydroquercetin ($IC_{50}=28.9\;{\mu}M$), and chlorogenic acid ($IC_{50}=30.6\;{\mu}M$) exhibited stronger antioxidant activity than L-ascorbic acid ($IC_{50}=31.5\;{\mu}M$) and ${\alpha}$-tocopherol ($IC_{50}=52.3\;{\mu}M$), whereas procatechuic acid ($IC_{50}=68.2\;{\mu}M$) showed lower activity. In addition, (+)-dihydrokaempferol ($IC_{50}=33.8\;{\mu}M$), trans-resveratrol ($IC_{50}=36.2\;{\mu}M$), moracin ($IC_{50}=47.6\;{\mu}M$), and 4-prenylmoracin ($IC_{50}=48.2\;{\mu}M$) exhibited moderate antioxidant activity. Furthermore, levels of the eleven polyphenolic compounds from three different types of mulberry seeds were quantified by HPLC, and their contents were as follows: rutin (311~60.0 mg/100 g)> quercitrin (7.2~34.2 mg/100 g)> (+)-dihydroquercetin (13.2~33.1 mg/100 g)> quercetin (15.8~19.5 mg/100 g)> 4-prenylmoracin (10.5~43.3 mg/100 g)> isoquercitrin (5.8~15.4 mg/100 g)> chlorogenic acid (0.0~15.3 mg/100 g)> moracin (4.7~7.2 mg/100 g)> procatechuic acid (0.0~11.6 mg/100 g)> (+)-dihydrokaempferol and trans-resveratrol (<0.1 mg/100 g). The 'Daesungppong' mulberry seeds among the three cultivars had higher flavonoid contents, such as rutin and quercetin derivatives, while the 'Iksuppong' seeds had the highest contents of phenolic acids and moracin derivatives. 'Cheongilppong' had lower amounts of polyphenolic compounds than the other two mulberry seeds. These results indicate that mulberry seeds containing antioxidant polyphenolic compounds may be potentially useful sources of anti-diabetic, anti-hypertensive, and anti-aging agents for functional foods and cosmetics.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.98-102
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• 2005

The MeOH extracts obtained from whole plant of Trigonotis peduncularis Benth. were solvent fractionated using EtOAc, n-BuOH and water, successively. The EtOAc and n-BuOH fractions gave four flavonol glycosides through application of silica gel and octadecyl silica gel (ODS) column chromatographies. The chemical structures of the flavonol glycosides were determined by the interpretation of several spectral data including 2D-NMR as $kaempferol-3-O-{\beta}-{D}-glucopyranoside\;(astragalin,\;1),\;kaempferol-3-O-{\alpha}-{L}-rhamnopyranosyl\;(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(nicotiflorin,\;2),\;quercetin-3-O-{\alpha}-{L}-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(rutin,\;3),\;quercetin-3-O-{\beta}-{D}-glucopyranoside\;(isoquercitrin,\;4)$. The flavonoids have been first isolated from this plant. Nicotiflorin $(100\;{\mu}g/ml)$ showed $68.3{\pm}1.2%$ of the inhibitory effect on hACAT1(human Acyl CoA: cholesterol transferase 1) activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.505-510
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• 1999

The seasonal variations of chemical composition of jujuba leaf were studied by analyzing general composition, amino acid composition, fatty acid composition, mineral, phenol, condensed tannin, flavonoid contents. Fresh jujuba leaf contained 4.42~6.31% protein and 4.31~5.71% fat on wet basis. Jujuba leaf was rich in aspartic acid, glutamic acid and leucine, but methionine was a limiting amino acid. Four kinds of free sugar, i.e. glucose, fructose, sucrose and maltose were found in jujuba leaf. The contents of fructose and glucose increased during growth, while the contents of disaccharides, sucrose and maltose, decreased. The main fatty acids of the leaf were palmitic acid, linoleic acid, stearic acid and oleic acid. Jujuba leaf was rich in K, Na and Ca, however, the amounts of Fe, Mn and Cu were low. The contents of Ca and Na increased during growth but the content of Mg decreased. The content of total phenolic compound was 0.83~0.89% and the content of condensed tannin was 0.40~0.45%. Two major flavonoids such as rutin and isoquercitrin were detected and their contents were 103.8~125.2mg/kg and 26.2~40.0mg/kg, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.15-21
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• 2003

Quantification of functional components, such as ［l -deoxynojirimycin (DNJ), ${\gamma}$-aminobutyric acid (GABA) and flavonoids］ of four different cultivars (YK-209, Cheongil, Yongchon and Kaeryang) and parts (upper, middle and lower) of mulberry leaves harvested in different areas and periods was performed by HPLC to select the best Quality of mulberry leaf suitable for manufacture of functional foods. Among four mulberry cultivars, YK-209 mulberry leaf had the highest DNJ, GABA and flavonoids levels. YK-209 mulberry leaf harvested in "Yeongcheon" area had greater DNJ, GABA and flavonoid contents than those harvested in "Sangju" area. Four major flavonoids of mulberry leaf were rutin, isoquercitrin, kaempferol-3-Ο-rutinoside, astragalin, and their levels varied greatly with cultivars. YK-BO9 mulberry leaf had the highest flavonoids content among four cultivars. DNJ, GABA and flavonoid contents of young YK-209 mulberry leaf were relatively higher in the upper part than those in the middle and lower parts. Additionally, levels of DNJ, GABA and flavonoids were higher in mulberry leaves harvested in the eariler growing season (May) than in the late growing seasons (June and August) . Particularly, among four flavonoids, rutin content had the highest in the mulberry leaf harvested in May, while isoquercitrin content did the highest in the mulberry leaf harvested in June and August. These results suggest that YK-209 mulberry leaf having high amount of functional components, such as DNJ, GABA and flavonoids, may be useful as potential source of beverages and tablets.verages and tablets.

• Journal of Life Science
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• v.32 no.7
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• pp.501-509
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• 2022

Pollen corrected from Quercus species is abundant in Korea and has been used to treat anemia and inflammation of the prostate gland. It is also used for hemostasis in oriental medicine. In this study, the ethanol extract of the acorn pollen and its subsequent organic solvent fractions using hexane, ethylacetate, butanol, and water residue were prepared, and their antioxidant, anti-thrombosis, and hemolysis activities were evaluated. The ethylacetate fraction of acorn pollen (EF-AP) showed the highest polyphenol content (225.0 mg/g) and strong antioxidant activity among the solvent fractions. The RC₅₀ of EF-AP against DPPH, ABTS, and nitrite radicals was 72.2, 27.7, and 62.6 ㎍/ml, respectively. The blood coagulation activities of the all-solvent fractions determined by thrombin time, prothrombin time, and activated partial thromboplastin time were negligible up to 5 mg/ml. Platelet aggregation inhibitory activities were observed in the EF-AP, butanol fraction, and water residue, whereas hexane fraction induced strong platelet aggregation. The EF-AP has no hemolysis activity against human RBC up to 1 mg/ml. UPLC/MS/MS analysis of the EF-AP revealed that rutin, isoquercitrin, and astragalin are major compounds for antioxidant and anti-thrombosis activities. Our results suggest that EF-AP could be developed as a noble antioxidant and anti-thrombosis agent.

• YAKHAK HOEJI
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• v.36 no.6
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• pp.556-562
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• 1992

Sevral flavonoids were isolated from the ethanol extract of Carthami flos which has been used in treatment of uterin congestion and also as analgesic and antiinflammatory. They were elucidated as kaempferol, quercetin, 6-hydroxy kaempferol, kaempferol 3-glucoside (Astragalin), quercetin 3-glucoside (isoquercitrin), quercetin 7-glucoside (quercimeritrin), kaempferol 3-rutinoside and quercetin 3-rutinoside (rutin). The structures of the isolated compounds were established by spectroscopic and chemical methods.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.199-203
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• 1994

Chemical examination of the leaves of Betula platyphylla var. latifolia has led to the isolation and characterization of five flavonoid glycosides including two C-glucosyl flavonoids. The structures of these compounds were elucidated as myricetin $3-O-{\alpha}-_L-rhamnoside$ (myricitrin), $quercetin-3-O-{\beta}-_D-glucopyranoside$ (isoquercitrin), $quercetin-3-O-{\beta}-_D-glucopyranoside$ (hyperoside), $nalingenin-6-C-{\beta}-_D-glucopyranoside$ (hemiphloin) and $aromadendrin-6-C-{\beta}-_D-glucopyranosidre(6-C-glucosyldihydrokaempferol)$ on the basis of physico-chemical and spectroscopic evidences.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.212-218
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• 1996

Two phenolcarboxylic acids. five flavonoids and one hydrolysable tannin were isolated from the leaves of Acer ginnala Maxim. On the basis of chemical and spectroscopic evidence, the strutures of these compounds were established as gallic acid, ethylgallate, acertannin, quercetin, quercitrin, isoquercitrin, rutin, $quercetin-3-O-{\alpha}-_L-rhamnopyranosyl-2'-gallate$.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.72-80
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• 2006

Fallen needle (8.5 kg) of Larix kaempferi were collected and extracted with 95% EtOH. The EtOH extracts were evaporated under reduced pressure, concentrated, and successively fractionated with a series of hexane, methylene chloride, ethylacetate and water on a separatory funnel to be freeze dried. A portion of ethylacetate and water soluble powder were chromatographed on a Sephadex LH-20 column eluting with aqueous MeOH and EtOH-hexane mixture. Spectrometric analyses such as NMR and FAB-MS, including TLC, were performed on the seven isolated compounds and were elucidated as (+)-catechin, (-)-epicatechin, 2"-O-rhamnosylvitexin, juglanin, afzelin, laricitrin-3-O-${\beta}$-D-glucopyranoside, isoquercitrin and cedrusin.