• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.8
• /
• pp.1194-1200
• /
• 2010

This study was carried out to investigate the compositional changes of ginsenosides and phenolic acids of ginseng leaf by fermentation in order to promote the utilization of ginseng leaf. The chief ginsenosides in non-fermented ginseng leaf (NFGL) were ginsenoside-Rg1 (26.0 mg/g), -Re (47.3 mg/g) and -Rd (23.9 mg/g). By fermentation, ginsenoside-Rg1, -Rb1, -Rb2, -Rb3, -Rc and -Re were decreased tremendously and new ginsenoside-Rh2, -Rh1, -Rg2 and -Rg3 appeared. Especially, ginsenoside-Rg3 (3.7 mg/g) on FGL was increased 15-fold compared to that of NFGL (0.2 mg/g). Total phenolic compound content of NFGL and FGL measured by colorimetric analysis was 350.4 and 312.5 mg%, respectively. There were 8 free and 6 ester forms of phenolic acids in NFGL. Among them, content of ferulic acid was the highest, comprised of 12.6 and 50.7 mg%, respectively. In FGL, total content of protocatechuic acid, p-hydroxybenzoic acid, and vanillic acid were increased by 28, 5 and 7.8 fold and ferulic acid was decreased greatly. Tyrosinase inhibitory activity of FGL was stronger than NFGL, while electron donating abilities of FGL were similar to NFGL.

• Korean Journal of Food Science and Technology
• /
• v.33 no.4
• /
• pp.497-500
• /
• 2001

The purpose of this study was to investigate the extraction method and antioxidative activities of phenolic compounds from Korean red tail ginseng. Antioxidative activities of red tail ginseng were evaluated with its ability to donate hydrogen to DPPH, and to inhibit the oxidation of linoleic acid and LDL induced by $H_2O_2$ and $FeCl_2$, respectivly by measuring the MDA formation. Total phenolic compounds expressed as % caffeic acid were 0.80%, 0.12%, 0.06%, 0.03%, 0.01% when red tail ginseng was consecutively extracted with 60% ethanol for 5 times, most of the phenolic compounds was recovered in the extract obtained after 3 times of extraction. The extraction efficacy of 60% ethanol was superior to that of water in extraction phenolic compounds, and the efficacy did not change after evaporating the extract followed by dissolving with water. 60% ethanol extract of red tail ginseng had weak ability to donate hydrogen to DPPH. MDA determination showed the antioxidative effect with inhibition ratio of 72.23% on linoleic acid oxidation by addition of red tail ginseng extract at the concentration of 1,500 ppm. 22.52% of LDL oxidation was inhibited by addition of 250 ppm.

• Journal of the Korean Society of Food Culture
• /
• v.33 no.1
• /
• pp.78-85
• /
• 2018

This study examined the changes in antioxidant activity and contents of phenolic compounds inblanched, steamed, and autoclaved burdock root (BR). The total polyphenolic and flavonoids contents of raw and cooked BR were determined spectrophotometrically. The antioxidant activity of BR was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and oxygen radical absorbance capacity (ORAC) assays. The main phenolic compounds in BR were quantified by HPLC (high performance liquid chromatography). Both blanching and steaming treatments significantly increased the antioxidant activities of BR in all groups (5 min, 15 min, and 30 min), whereas in autoclaving treatment, the 30 min treatment only showed an increase in the antioxidant activities of BR. The 30 min blanched BR exhibited the strongest DPPH and ABTS radical scavenging activities and possessed the highest total polyphenol and flavonoid phenolic contents. The 15 min-steamed BR showed the highest ORAC value. The main phenolic compound of the 15 min-steamed BR was CGA (chlorogenic acid). These results suggest that heat cooking methods, such as blanching and steaming, improve the antioxidant activity of BR by increasing the concentration of phenolic compounds.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.7
• /
• pp.959-968
• /
• 2014

The changes in the ${\beta}$-glucosidase activity, total phenolic contents, isoflavone contents, and antioxidant activities during the fermentation of cheonggukjang by Bacillus amyloliquefaciens MJ1-4 with and without garlic were investigated. The levels of total phenolic and isoflavone-malonylglycoside, -acetylglycoside, and -aglycone contents increased, whereas the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and ferric reducing/antioxidant power (FRAP) assay results increased, but isoflavone-glycoside levels decreased during cheonggukjang fermentation. The levels of total phenolic and total isoflavone contents and the antioxidant activities were higher in cheonggukjang fermented without garlic (CFWOG) than in cheonggukjang fermented with garlic (CFWG) after 24 h of fermentation, but they were lower in CFWOG than in CFWG after 72 h of fermentation. In particular, the highest levels of total phenolic, daidzein, glycitein, and genistein were present at concentrations of 15.18 mg/g, $264.4{\mu}g/g$, $16.4{\mu}g/g$, and $31.1{\mu}g/g$ after 72 h of fermentation in CFWG, showing 82.89% in DPPH radical scavenging activity, 106.32% in ABTS radical scavenging activity, and 1.47 ($OD_{593nm}$) in FRAP assay, respectively. From these results, we suggest that the high antioxidant activity of CFWG might be related to the markedly higher levels of total phenolic contents, isoflavone-malonylglycosides, -acetylglycosides, and -aglycones achieved during fermentation.

• Food Science and Biotechnology
• /
• v.18 no.4
• /
• pp.1051-1054
• /
• 2009

This study was conducted to investigate the antioxidant activity of the extracts of lotus (Nelumbo nucifera Gaertner). The total phenolic contents in leaf, stem, and root were 165, 74, and 30 tannic acid equivalent mg/g of dried extract or fraction respectively. The butanol and ethylacetate fractions of lotus parts showed higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than other fractions. 2,2'-Azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging activity also showed the similar result as the DPPH radical scavenging activity. The antioxidative capacity of the ethylacetate fraction was the highest among fractions and its fraction showed higher contents of total polyphenol.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.3
• /
• pp.381-388
• /
• 2014

The antioxidant activities of extracts from Rubus coreanus Miquel (black raspberry) and Morus alba L. (mulberry) fruits were investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2-azino-bis-(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS) assay, and reducing power assay. Aqueous mixtures of ethanol, methanol, and acetone were analyzed in order to determine the most effective extraction solvent for the two fruits. Black raspberry and mulberry extracts with the 60:40 acetone-water mixtures (v/v) showed the highest DPPH radical scavenging activities (56.2 and 85.2%, respectively) compared to the other extraction solvents. The 60% acetone extract was finally selected as an extraction solvent and then sequentially fractionated according to solvent polarity. Among the fractions of the two fruits, the ethyl acetate fraction showed the highest antioxidant activity as well as total phenolic and total flavonoid contents. In addition, there were high correlation coefficients between antioxidant activities and their contents. The $EC_{50}$ value of the ethyl acetate fraction from mulberry fruit was 2.2 times lower than that of butylated hydroxytoluene (BHT) in DPPH assay. The major phenolic acid and anthocyanin of the two fruits were protocatechuic acid and cyanidin-3-glucoside, respectively.

• Journal of the Korean Applied Science and Technology
• /
• v.11 no.1
• /
• pp.7-16
• /
• 1994

Some seeds of the Rutaceae family, Zanthoxylum piperitum, Z. schinifolium officinalis, Poncirus trifoliata, Citrus unshin, were investigated to clarify their antioxidative components. Finely powdered samples were extracted by hexane, followed by dichioromethane and then 70% methanol in a hot bath. Its unsaponifiables containing X-and Y-tocopherol with trace amount of ${\beta}-and$\;{\delta}-tocopherol$. also showed comparatively weak activity, although the hexane fraction itself had no significant antioxidative effect on lard. Levels of total tocopherols in the samples averages 42. 24-154. 11 mg/lOOg total extractives. The dichloromethane-and 70% methanol extractives showed strong antioxidative activity, from which antioxidative substances were purified with benzene-acetone(6:5, V/V) on a silica gel column, and with a solvent mixture of acetonitrile-methanol-$H_2O$(40:40:20, V/V/V) on a Sep-Pak $C_{18}$ hydrolyzed by 5% KOH-ethanol. The recovered unsaponifiables were, then, separated on a column of high performance liquid chromatography. The unsaponifiables produced by hydrolysis of the isolates from dichloromethane extractives has epi-catechin(40.0-57.1%) and (+)-catechin<$l9.1{\sim}24.4%$ to total phenolic substances, on area base) as major component, accompanied by chlorogenic acid, gallic acid(?), trans-p-coumaric acid and tralls-p-ferulic acid including some unknown components, and those derived from 70% methanol extractives also comprise (+)-catechin($31.3{\sim}39.6%$ to total components, on area base), epi-catechin($2O.2{\sim}36.4%$), trans-p-cournaric acid(8.4-15.3%) and trans-p-ferulic acid($7.7{\sim}14.1%$) as predominant component with some minor coponents, but the fraction supposed to be gallic acid(?) is not present. The antioxidative activities of the phenolic components isolated in this work were in order of epi-catechin>catechin>chlorogenic acid>trans-p-ferluic acid>trans-p-coumaric acid.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.4
• /
• pp.346-354
• /
• 2018

Kemenyan resin from Styrax sumatrana is a unique non-timber forest product (NTFP) native from Sumatera Island, Indonesia. It possesses a wide range of applications in the pharmaceutical, perfume, and cosmetics industries. In this paper, six kemenyan resin samples were investigated to evaluate their free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) reagent. The kemenyan resin samples, which originated from North Tapanuli, Pakpak Bharat, and Humbang Hasundutan, showed high antioxidant activity with $IC_{50}$ < 16 mg/L. The antioxidant activity of common kemenyan resin constituents, i.e., cinnamic acid, ethyl cinnamate, gallic acid, and vanillin was also investigated as positive control, although they exhibited lower antioxidant activity ($IC_{50}$ < 1000 mg/L), except for gallic acid ($IC_{50}$ = 5,23 mg/L). The total phenolic and flavonoid contents (TPC and TFC) for all samples were 44-66 mg gallic acid equivalents (GAE)/g sample and 143-160 mg quarcetin equivalents (QE)/g sample. The results revealed that kemenyan resin has high potency as an antioxidant and could be used as a natural antioxidant resource.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.8
• /
• pp.937-943
• /
• 2017

This study was performed to investigate the changes between free and bound forms of bioactive compounds in germinated adzuki bean. Adzuki bean was germinated at $25^{\circ}C$ for 6 days, and then free and bound forms of bioactive compounds were extracted. Total free polyphenol and flavonoid contents in of raw adzuki bean increased from 0.91 mg/g and 0.60 mg/g in before germination to 2.37 mg/g and 3.03 mg/g in at 6 days after germination, respectively. Bound polyphenol, flavonoid, and phenolic acid contents also increased with increasing germination periods, whereas bound polyphenol and flavonoid contents slightly reduced in at 2 days after germination. The total phenolic acid contents, including ferulic acid, veratric acid, hesperidin, salicylic acid, naringenin, and hesperidin, increased during germination, and germination process can convert compounds to phenolic acid via anabolism and catabolism. Total anthocyanin and anthocyanidin contents of adzuki bean decreased during germination due to hydration by water during soaking or enzyme activation of anthocyanase during germination. These results suggest that the germination process increased utilization of functional compounds such as phenolic compound and isoflavones in black soybean.

• Korean Journal of Pharmacognosy
• /
• v.44 no.3
• /
• pp.220-223
• /
• 2013

In the course of screening tyrosinase inhibitory activity, total methanolic extract and EtOAc-soluble fraction of Smilax china leaves showed significant inhibitory activity. Further fractionation and isolation of the EtOAc-soluble fraction resulted in 12 phenolic compounds, which were identified as 4-hydroxybenzoic acid (1), 3,4-dihydroxybenzaldehyde (2), 3,4-dihydroxybenzoic acid (3), 3,4-dihydroxyacetophenone (4), 3-hydroxy-4-methoxy benzoic acid (5), trans-p-hydroxycinnamic acid (6), cis-p-hydroxycinnamic acid (7), trans-resveratrol (8), cis-resveratrol (9), dihydroresveratrol (10), moracin M (11) and kaempferol (12). Compounds 1-11 were first reported from this plant. Among the isolated compounds, compounds 2, 8, 9 and 12 showed strong inhibition on tyrosinase activity.