• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1698-1704
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• 2012

Resveratrol, or its glycoside form piceid, is a dietary antioxidant polyphenolic compound, found in grapes and red wine that has been shown to have protective effects against cardiovascular disease. However, very low water solubility of the compound may limit its application in the food and pharmaceutical industries. The amylosucrase (AMAS) of Alteromonas macleodii Deep ecotype was expressed in Escherichia coli and showed high glycosyltransferase activity to produce the glucosyl piceid when piceid was used as an acceptor. The conversion yield of piceid glucoside was 35.2%. Biotransformation using culture of the E. coli harboring the amas gene increased the yield up to 70.8%. The transfer product was purified by reverse phase chromatography and recycling preparative HPLC, and the molecular structure of the piceid glucoside was determined using NMR spectroscopy. The piceid glucoside was identified as glucosyl-${\alpha}$-($1{\rightarrow}4$)-piceid. The solubility of glucosyl piceid was 5.26 and 1.14 times higher than those of resveratrol and piceid, respectively. It is anticipated that dietary intake of this compound is more effective by enhancing the bioavailability of resveratrol in the human body because of its hydrophilic properties in the intestinal fluid.

• Journal of Microbiology and Biotechnology
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• v.31 no.12
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• pp.1692-1700
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• 2021

Glycosylation of resveratrol was carried out by using the amylosucrase of Deinococcus geothermalis, and the glycosylated products were tested for their solubility, chemical stability, and biological activities. We synthesized and identified these two major glycosylated products as resveratrol-4'-O-α-glucoside and resveratrol-3-O-α-glucoside by nuclear magnetic resonance analysis with a ratio of 5:1. The water solubilities of the two resveratrol-α-glucoside isomers (α-piceid isomers) were approximately 3.6 and 13.5 times higher than that of β-piceid and resveratrol, respectively, and they were also highly stable in buffered solutions. The antioxidant activity of the α-piceid isomers, examined by radical scavenging capability, showed it to be initially lower than that of resveratrol, but as time passed, the α-piceid isomers' activity reached a level similar to that of resveratrol. The α-piceid isomers also showed better inhibitory activity against tyrosinase and melanin synthesis in B16F10 melanoma cells than β-piceid. The cellular uptake of the α-piceid isomers, which was assessed by ultra-performance liquid chromatography (UPLC) analysis of the cell-free extracts of B16F10 melanoma cells, demonstrated that the glycosylated form of resveratrol was gradually converted to resveratrol inside the cells. These results indicate that the enzymatic glycosylation of resveratrol could be a useful method for enhancing the bioavailability of resveratrol.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.493-500
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• 2012

In order to confirm the possibility of UV utilization as a means for disease protection in grapevine the stilbene contents and the disease incidence in UV irradiated leaves were investigated. UV irradiation significantly increased the contents of resveratrol, piceatannol and piceid, in them, resveratrol and piceid showed in vitro inhibition of spore germination and mycelium growth of Botrytis cinerea. The accumulation of both the stilbenes in UV irradiated leaves seems to be enough to inhibit the B. cinerea growth, since the formation of necrotic spot on the leaves was considerably inhibited when they were inoculated with the conidial spores of B. cinerea. However the stilbenes were accumulated only in the leaves exposed directly to UV showing a limited translocation ability of the compounds. Thus it would be necessary to develop a method to evenly irradiate the entire crown of plant with UV in order to expect to protect them from disease by UV irradiation.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.675-678
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• 2008

Permeability of resveratrol, piceid, rhapontigenin, and rhaponticin in Caco-2 cell assays using high-performance liquid chromatography were compared. Caco-2 cell monolayers were used to evaluate the transport rates of stilbene analogues from the apical to the basolateral sides. All stilbenes experimented in this study were transported to the basolateral side by times. For comparing the permeability of 4 stilbenes, we calculated the slope of the cumulative concentration of each stilbene in basolateral sides over time, resulting in those values of resveratrol, piceid, rhapontigenin, and rhaponticin with $3.766{\times}10^{-5}$, $4.330{\times}10^{-6}$, $5.430{\times}10^{-5}$, and $2.458{\times}10^{-5}\;{\mu}M/sec$, respectively. Apparent permeability coefficient of resveratrol and rhapontigenin were calculated to $9.994{\times}10^{-6}$ and $1.441{\times}10^{-6}\;cm/sec$, respectively, while those of piceid and rhaponticin were to $1.149{\times}10^{-7}$ and $6.523{\times}10^{-7}\;cm/sec$, respectively. These results suggest that aglycones would be absorbed more effectively than glycosides in stilbenoids.

• Research in Plant Disease
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• v.19 no.3
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• pp.177-182
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• 2013

Resvestrol has been known to inhibit bacterial and fungal growth in vitro, and can be accumulated in plant to concentrations necessary to inhibit microbial pathogens. Hence, stilbene synthase gene has been used to transform to synthesize resveratrol in heterologous plant species to enhance resistance against pathogens. In the present study, we investigated the antimicrobial activities of resveratrol and piceid to bacterial and fungal pathogens, which causing severe damages to rice plants. In addition, disease resistance was compared between transgenic rice varieties, Iksan 515 and Iksan 526 transformed with stlibene synthase gene and non-transgenic rice varieties, Dongjin and Nampyeong. Minimum inhibitory concentration of resveratrol for Burkolderia glumae was 437.5 ${\mu}M$, and the mycelial growth of Biplaris oryzae was slightly inhibited at concentration of 10 ${\mu}M$. However, other bacterial and fungal pathogens are not inhibited by resveratrol and piceid. The expression of the stilbene synthase gene in Iksan 515 and Iksan 526 did not significantly enhanced resistance against bacterial grain rot, bacterial leaf blight, sheath blight, and leaf blight. This study is the first report on the effect of resveratrol and piceid against pathogens of rice plant, and changes of disease resistance of transgenic rice plants transformed with stilbene synthase gene.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.124-128
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• 2008

This study was aimed to analyze the composition and to quantify the contents of stilbenoids in the leaves and fruits of Morus alba L. using high performance liquid chromatography with phodtodiode array detector and UV detector. Optimal wavelength for the detection of various stilbenoids such as resveratrol, piceatannol, rhapontigenin, astringin, pterostilbene, piceid, rhaponticin and vitisin A was screened by DAD detector and set to 308 nm. Seven kinds of stilbenoids except vitisin A were identified in fruits, while 5 kinds of stilbenoids in leaves. Total stilbenoids contents were $609.15{\pm}7.24$ mg/100 g d.w. in fruits and $188.57{\pm}1.70$ mg/100 g d.w in leaves. Stilbenoids contents in fruits were 3 times higher than those in leaves. Rhaponticin was the most profound stilbene, analyzed to $389.26{\pm}5.22$ mg/100 g d.w. (63.8% of total stilbenoids) in fruits and $99.17{\pm}2.79$ mg/100 g d.w. (52.5% of total stilbenoids) in leaves. Astringin and piceatannol were only detected in fruits and vitisin A was not detected. Contents of piceid and rhaponticin were higher than those of aglycone forms, rhapontigenin and resveratrol.

• Archives of Pharmacal Research
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• v.17 no.1
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• pp.42-44
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• 1994

The activity-guided fractionation of some medicinal plants led to yield five kinds of natural stilbene compounds namely 3, 5-dihydroxy-4'-methoxystillbene(I), rhapontigenin(II), reveratrol(III), rhaponticin(IV) and piceid(V) and two common flavonoids, apigenin(VI) and luteolin(VII) as active principles of the antitumor property, in vitro, against five kinds of human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT15.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1680-1682
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• 2003

• Horticultural Science & Technology
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• v.30 no.6
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• pp.626-634
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• 2012

There are variations among grapevine genotypes in the levels of tolerance to cold, and cold-hardiness of grapevine has been affected by the change of short-term environment during over-wintering. In this study, the responses of vines to cold in open field and rain-shelter system were investigated to obtain useful information in increasing the tolerance to cold in grape cultivation. Total carbohydrate content of bearing mother branches was higher in the rain-shelter system than in the open field, and lower in the branches of 'Muscat Bailey A' than in 'Campbell Early' and 'Kyoho'. Bud-burst and shoot growth were better in the rain-shelter system than in open field, whereas there is no significant difference among the treatments of net beside vines. There was also low incidence of gray mold in rain shelter system. Stilbene compounds such as t-piceid, resveratrol, piceatannol, c-piceid were accumulated in the cold-treated shoot from vine cuts harvested in rain shelter system. Genes of chalcone isomerase, manganese superoxide dismutase, proline rich protein 2, and temperature induced lipocalin were highly expressed in the cold-treated shoot from vine cuts harvested in rain shelter system. While there was not change of air temperature, but high reduction of wind speed in the rain shelter system compared to open field, and increase in the reduction of wind speed by net treatment. The damage of grapevines by cold in the extreme low temperature could be reduced by keeping them in the rain shelter system with net during winter season.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.703-706
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• 1998

The anticomplementary activity of stilbenes from medicinal plants in Korea was investigated in vitro. 3,5-Dihydroxy-4'-methoxystilbene (3) was most potent with $IC_{50}$ value of $1.5{\times}10^{-4}M$ followed by rhapontigenin (4), oxyresverastrol (2), 2,3,4',5-tetrahydroxystilbene-2-O-beta-glucoside (9), rhaponticin (8), resverastrol (1), and piceid (7). The activity was found to be increased by a methylation on a hydroxy group of C-4' of 1, but decreased by further methylation on hydroxy groups of C-3 and C-5 and glucosylation on any hydroxy group of 1. Addition of hydroxy group on C-2' of 1 or C-3' of 3 was little affected on the anticomplementary activity but the activity was increased by O-glucosylation on C-2 of 1.