• YAKHAK HOEJI
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• v.44 no.4
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• pp.354-357
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• 2000

Two ellagitannins, pedunculagin and 2,3-(S)-Hexahydroxydiphenoyl (HHDP)-D -glucose and three condensed tannins, (+)-catechin, (-)-epicatechin and procyanidin B-4 which were isolated from Rubus coreanum were evaluated for their antioxidative effects with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and lipid peroxidation generation system mediated by addition of $H_2O$$_2$to rat liver homogenate (TBARS). The ellagitannins, 2,3-(S)-HHDP-D-glucose and pedunculagin, showed more potent antioxidative activities by DPPH and TBARS than condensed tannins.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.209-216
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• 2012

In the continued research on natural fungicides for control of plant diseases by using plant-derived products, we found that Spatholobus suberectus Dunn had a strong fungicidal activity against several plant pathogens. S. suberectus (1 kg) was extracted with 80% aqueous MeOH and then the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$ successively. The four layers were tested their disease contron efficacies against 6 plant diseases such as rice blast (RCB), rice sheath blight (RSB), tomato grey mold (TGM), tomato late blight (TLB), wheat leaf rust (WLR), and barley powdery mildew (BPM). The EtOAc fraction was highly active showing over 80% control against RCB, TGM, TLB, and BPM. By using silica gel chromatography, preparative TLC and HPLC, six compounds that were expected to have antifungal activity were separated. Their chemical structures were identified as ethanone, hydroxytyrosol, epicatechin, procyanidin B2, dimethoxy daizein and formononetin by ESI-MS, $^1H$-NMR, $^{13}C$-NMR, and 2D-NMR spectroscopic analyses. The chemicals except epicatechin were first reported in S. suberectus. Study on in vitro and in vivo antifungal activities of the isolated compounds is in progress.

• Advances in Traditional Medicine
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• v.4 no.4
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• pp.267-273
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• 2004

Oxidative stress is associated with many kinds of chronic diseases. Antioxidants such as polyphenols are compounds that protect cells against the damaging effects of reactive oxygen species. Grape seeds are considered good resources of polyphenols, and grape seed extracts have a very strong antioxidant effect. In the present study, we established a simple gradient reverse-phase high performance liquid chromatography method to determine polyphenol content from three different grape seed resources. An ODS (2), $150\;{\times}\;3.2\;mm$ column has been employed, and six polyphenols have been determined: gallic acid, protochatechuic acid, (+)-catechin, (-)-epicatechin, procyanidin B2, and epicatechin gallate. Catechin and epicatechin were the main polyphenol compounds in all three extracts. The amount of procyanidin B2 was higher in Extract 1 (from a company of China), while Extract 2 (extracted in our lab) and Extract 3 (from a company of USA) contained higher proportions of epicatechin gallate. For the total polyphenol content, Extract 1 was much higher than that of Extract 2 and 3. The results suggest that the dietary dose of grape seed extracts from different resources should be adjusted according to polyphenol content.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.576-585
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• 2003

An improved method in place of a conventional vanillin spectroscopic method (CVSM) was developed for determination of catechin and its derivatives in extract and oil of grape seeds. For the CVSM, grape seed extracts had relatively high catechin content in the range of $17{\sim}43%$ (g/100g of extract), while grape seed oils had relatively smaller catechin content in the range of $30{\sim}40mg%$ (mg/100g of oil). For the improved vanillin spectroscopic method (IVSM) using a polyamide cartridge, catechin content of grape seed extracts was in the range of $4.0{\sim}7.5%$, while that of grape seed oils was below 5 ppm. Meanwhile, the quantities of catechin and its derivatives were determined by HPLC in the grape seed extracts and oils. Four major catechins [(+)-catechin, procyanidin B2, (-)-epicatechin, and epicatechin gallate] were detected from grape seed extracts, and the ranges of concentrations were as follows: (+)-catechin, $1.35{\sim}2.60%$; procyanidin $B_2$, $0.77{\sim}1.36%$; (-)-epicatechin, $2.35{\sim}4.59%$; (-)-epicatechin gallate, $0.06{\sim}0.30%$. In contrast, four catechins were barely detectable in the grape seed oils. The reproducibility of four major catechins in grape seed extracts, given as coefficient of variation, was below 5%, and the recovery close to above 95%. The achieved detection level of four catechins was $1{\sim}5\;ppm$. Additionally, the contents of catechin compositions in grape seed extract were also determined by HPLC in relation to different cultivars and producing areas. Thus, HPLC method and IVSM using polyamide cartridge can be used as alternative to CVSM for determination of catechin and its derivatives in extract and oil of grape seeds.

• Korean Journal of Plant Resources
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• v.23 no.3
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• pp.223-227
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• 2010

In order to select superior tree from Korea, five major phenolic compounds including (-)-epicatechin(EC), chlorogenic acid (ChA), hyperoside (HP), isoquercitrin (IQ), and procyanidin B2 (PC-$B_2$) in hawthorn fruit were evaluated. We also compared these hawthorn fruits of five clones with Chinese hawthorn cultivars. HPLC with a diode-array detector was used to determine the contents of the individual compounds. Hawthorn fruits of five clones (selected from different area of Korea), and four Chinese hawthorn cultivars grown in the Korea Forest Research Institute (Suwon) were utilized. With their high functional components, Jungsun is the clone including the highest contents of EC (11.26 mg/g) and PC-$B_2$ (24.46 mg/g). The clone of Chuncheon 15 had highest HP (0.53 mg/g) and IQ (0.41 mg/g). From the results, the clone of Jungsun and Chuncheon 15 can be evaluated to be selected breeding material for cultivar development.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.196.2-196.2
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• 2003

The Barks of Ulmus davidiana (Ulmaceae) have been used for the treatment of insecticide, anti-boil and anti-fungi in Korean traditional medicine. Four phenolic compounds were isolated from 80% Acetone extracts. The structures of these compounds were elucidated as (+)-catechin, (+)-catechin 7-O-${\beta}$-D-glucopyranoside, (+)-catechin 7-O-${\beta}$-D-xylopyranoside and procyanidin B-1. These phenolic compounds showed significant nitrogen monoxide(NO) production inhibitory activity in IFN-${\gamma}$, LPS stimulated RAW 264.7 cell and also showed significant antioxidative activity on DPPH radical. (omitted)

• Applied Biological Chemistry
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• v.47 no.1
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• pp.72-77
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• 2004

The purpose of this research was to determine the effect of phenol compounds from green tea leaves and surfactant micelles on lipid oxidation in com oil-in-water emulsion (O/W). The concentration of phenol and surfactant in continuous phase of the O/W with exceed Brij 700 and phenol compounds was measured. The particle size of O/W with phenol (100 ppm) increased with increasing added exceed surfactant $(0{\sim}2.0%)$ and the concentration of surfactant and phenols in the continuous phase higher than these of control. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing phenol compounds (100 ppm) and exceed surfactant $(0{\sim}2.0%)$ decreased with increasing concentration of exceed surfactant. The ability of the phenol compounds and exceed surfactant to inhibit hydroperoxide and headspace hexanal producing as lipid oxidation in O/W was BHT>procyanidin B3-3-O-gallate> (+)-gallocatechin > (+)-catechin and 2% > 1 % > 0% of exceed surfactant. These results indicate that phenol compounds and exceed surfactant could alter the physical location of hydroperoxide in O/W.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.53-62
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• 2010

The effect of far-infrared (FIR) irradiation on the functional compounds of grape seeds extract were evaluated. Grape seed was dried on different heating power (0, 900, 1800 W) and heating time (0, 20, 40 min) with far-infrared drier. Contents of soluble solids, catechins, total phenolics and total flavonoids along with Hunter's color value, electron donating ability (EDA) and nitrite scavenging activity were analyzed. The soluble solids, Hunter's L value and a value were not significantly different from control samples. Cathechin, procyanidin $B_2$ and epicatechin contents changed with heating time. In the treated sample, total cathechins content was found maximum at 900 W of heating power and 20 min of heating time with a high level of total phenolics, total flavonids and EDA. These results indicated that FIR irradiation of grape seed could enhance antioxidant activities of its extracts by increasing the amounts of functional compounds. Moreover, response surface methodology(RSM) was applied to predict optimum conditions for heating by FIR rays of grape seeds. Based on superimposition of contour map with respect to total phenolics, total catechin and EDA, optimum ranges of heating conditions were heating power of 621.82~818.18 W and heating time of 16.3~19.83 min.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.144-149
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• 2004

Changes in functional constituents of grape (Vitis vinifera) seeds prepared by three different heat pretreatments were determined and compared with those of non-treated grape seed. The recovery of grape seed oils was generally increased by roasting, steaming and microwave processes, although the recovery of specific constituents varied among three heat pretreatments. The recovery of MeOH extracts of the seeds increased following the roasting process, whereas that of MeOH extracts decreased gradually with steaming and microwave treatments. Levels of four catechins in grape seeds: (+)-catechin, procyanidin B$_2$, (-)-epicatechin, and (-)-epicatechin gallate, were decreased with increased roasting and steaming time, but were unaffected by microwave treatment. During the three different heat pretreatments, levels and compositions of fatty acid did not change, whereas those of phytosterol compositions decreased greatly. These results suggest that a mild heat pretreatment, controlled for temperature and time, is needed to prevent a considerable loss in the level of valuable functional components in grape seed.

• Journal of the Korean Wood Science and Technology
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• v.38 no.5
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• pp.444-449
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• 2010

Ulmus davidiana var. japonica is a deciduous tree used in traditional medicine. In this study, we examined the antioxidant and anti-inflammatory activity of extracts and compounds isolated from U. davidiana var. japonica stem barks for development of cosmetic phyto-materials. Phytochemical examination of the stem bark led to the isolation and characterization of three known compounds, (+)-catechin (1), (+)-catechin-7-O-${\beta}$-D-apiofuranoside (2), and procyanidin B3 ((+)-catechin-($4{\alpha}{\to}8$)-(+)-catechin) (3). Their bioactivities including antioxidant (DPPH ree radical scavenging assay) activity, anti-inflammatory (nitric oxide nhibition assay) were evaluated. Most of the crude extracts and isolates indicated significant antioxidant potential compared with BHT and ${\alpha}$-tocopherol as controls. Futhermore, all compounds showed higher inhibitory activities for NO production in Raw 264.7 cells than the L-NMMA using the positive control. Eespecially, (+)-catechin (1) and (+)-catechin-7-O-${\beta}$-D-apiofuranoside (2) which could inhibit more than 90% of the NO production at a concentration of 100 ${\mu}g/m{\ell}$, implying excellent anti-inflammatory activity.