• Journal of Microbiology and Biotechnology
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• v.19 no.4
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• pp.387-390
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• 2009

Microbial UDP-glycosyltransferases can convert many small lipophilic compounds into glycons using uridine-diphosphate-activated sugars. The glycosylation of flavonoids affects solubility, stability, and bioavailability. The gene encoding the UDP-glycosyltransferase from Bacillus cereus, BcGT-3, was cloned by PCR and sequenced. BcGT-3 was expressed in Escherichia coli BL21(DE3) with a glutathione S-transferase tag and purified using a glutathione S-transferase affinity column. BcGT-3 was tested for activity on several substrates including genistein, kaempferol, luteolin, naringenin, and quercetin. Flavonols were the best substrates for BcGT-3. The enzyme dominantly glycosylated the 3-hydroxyl group, but the 7-hydroxyl group was glycosylated when the 3-hydroxyl group was not available. The kaempferol reaction products were identified as kaempferol-3-O-glucoside and kaempferol-3,7-O-diglucoside. Kaempferol was the most effective substrate tested. Based on HPLC, LC/MS, and NMR analyses of the reaction products, we conclude that BcGT-3 can be used for the synthesis of kaempferol 3,7-O-diglucose.

• Nutrition Research and Practice
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• v.2 no.1
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• pp.46-49
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• 2008

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with ${\lambda}_{max}$ of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.768-777
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• 2013

Physicochemical characteristics and analysis of functional constituents of mulberry (Morus alba L.) fruit juices were investigated according to four different mulberry cultivars, including iksuppong, daeseongppong, cheongilppong and kwasangppong. Among the four mulberry cultivars examined, the small-sized cheongilppong had higher soluble solid content and lower titratable acidity, whereas the big-sized daeseongppong had higher titratable acidity and lower soluble solid content than other mulberry cultivars. Cheongilppong had higher contents of fructose and glucose, while daeseongppong had higher contents of citric and malic acids than the other mulberry cultivars. Kwasangppong had higher contents of two anthocyanins, cyanidin 3-glucoside and cyanidin 3-rutinoside, while cheongilppong had lower contents of two anthocyanins than the other mulberry cultivars. Daeseongppong had higher contents of resveratrols, flavonoids and moracin, whereas cheongilppong had higher levels of protocatechuic, chlorogenic and caffeic acids than the other mulberry fruits. Of the four mulberry cultivars, daeseongppong and cheongilppong had higher contents of GABA and DNJ, respectively, than the other mulberry cultivars. These results provide useful information to food technologists for the development and standardization of high quality mulberry juices as well as their processed foods.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.705-708
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• 2001

Enzymatic synthesis and purification of sugar esters using supercritical $CO_2$ were investigated. The observed yield of suagr ester produced by transesterification of methyl glucoside and oleic acid using a lipase(Novozym 435) was 67% at 24 hours of reaction in the supercritical $CO_2$. The solubility of the fatty acids in the supercritical $CO_2$ was measured to find the conditions of supercritical separation of the fatty acids from the reaction mixture. The solubility of capric and oleic acid was 5 ${\times}$ $10^{-4}$, 1.7 ${\times}$ $10^{-4}$ mol/mol $CO_2$, respectively, varying at $35{\sim}50^{\circ}C$ and 80${\sim}$120 atm.

• Journal of Environmental Science International
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• v.17 no.1
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• pp.19-27
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• 2008

Artichoke extracts are widely used alone or in association with other herbs for embittering alcoholic and soft drinks and to prepare herbal teas or herbal medicinal products in Viet Nam. The objective of this paper was a screening of flavonoids and total phenolic compounds content in the parts of artichoke (Cynara scolymus L.) as flowers, leaves, roots, trunks, stumps, The total phenolic compounds and flavonoids in the parts of artichoke were extracted among 3 extraction methods as methanol extraction (EM1), mixing methanol and water method (EM2) and water extraction method (EM3). Total phenolic compounds and flavonoids were determined by UV/VIS, HPLC techniques. The apigenin 7-O-glucosides, cynarin, narirutin, gallic acid, caffeic acid were found as the main flavonoids constituents in all parts of artichoke. It showed that value of total phenolic compounds and flavonoids by EM3 were higher than that of total phenolic compounds and flavonoids by EM1 and EM2. Furthermore, the results of this study revealed that total phenolic compounds and flavonoids, obtained by these convenient extraction methods, may show the quick efficacy of artichoke in all respects of their quality and quantity.

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.284-287
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• 2005

The flowers of Chrysanthemum boreale Makino were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$. Two compounds from the n-hexane fraction and one glucoside from the n-BuOH fraction were isolated through the repeated silica gel and ODS column chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\beta}-sitosterol$ (1), phytol (2) and zingerone $4-O-{\beta}-D-glucopyranoside$ (3). Compounds 2 and 3 were isolated for the first time from this plant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.255-260
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• 1996

증편반죽의 발효에 따른 해면상의 조직(망상구조)형성능의 mechanism을 조사하기 위하여 반죽의 구성성분의 경시적 물성 및 효소(diastase 및 protease) 활성의 변화, 구성 전분 분획의 glucose chain length 변화 및 1% SDS에 의해서 용출되는 단백질 분획의 변화에 대해서 검토하였다. 발효가 진행됨에 따라 증편반죽의 pH는 감소한 반면 점성 및 부피는 발효경과 10시간가지 증가하다가 그 이후로는 약간 감소하는 경향을 보였다. 발효의 진행과 더불어 diastase의 활성은 증가하였으며, 쌀전분 분획 중 amylose의 함량은 약간 감소하였다. 그리고 전분분자의 $\alpha-1,6-glucoside$ 결합을 isoamylase(debranching enzyme)로 가수분해시킨 후 Sephadex G-75를 이용한 chromatogram 분석에 의하면 쌀가루 전분 분획과 증편반죽 전분 분획의 glucose chain length 분포는 거의 유사하지만 발효가 진행됨에 따라 중합도가 낮은 부분이 우선적으로 diastase의 작용을 받은 것이라고 생각되어진다. 한편, 발효가 진행된에 따라 protease의 활성은 증가하고 있었음에도 불구하고 증편반죽의 당에 의한 단백질 분획의 고분자화가 Suprose CL-12 column chromatogram 상에서 관찰되었는데, 이것은 아마도 발효과정 중 증편반죽에 공존하는 미생물들의 발효산물인 당질(gum질)을 매개로 한 단백질 분자의 회합에 의한 결과라고 생각되어진다. 따라서 이러한 결과를 미루어 볼 때 증편반죽의 망상구조 형성능은 발효과정 중 일어나는 당과 단백질간의 상호작용에 의한 결과라 생각되어진다.

• Analytical Science and Technology
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• v.6 no.3
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• pp.335-343
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• 1993

The structure of cerebrosides from soybean embryo was determined using fast atom bombardment mass spectrometer (FAB-MS), gas chromatography mass spectrometer (GC-MS) and TLC. The components of cerebroside were determined by GC-MS after acid hydrolysis. The molecular weight distribution of cerebroside was measured by positive mode FAB-MS with LiOH saturated 3-nitrobenzylalcohol(3-NBA) matrix. Structures of individual components of complex mixtures can be determined easily by this process. The major constituent of soybean extracted cerebroside was determined as the glucoside of N-2'-hydroxypalmitoyl-sphingadienine.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.439-443
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• 2007

The effects of the methanol extract of the leaves of Brassica juncea and isorhamnetin $3-O-{\beta}-D-glucopyranoside$, major compound isolated from the ethyl acetate fraction of this plant on hepatic lipid peroxidation and drug-metabolizing enzymes, were evaluated in rats treated with bromobenzene. The extract and isorhamnetin $3-O-{\beta}-D-glucopyranoside$ of oral administration did not show any significant effects on activities of aminopyrine N-demethylase and aniline hydroxylase, enzymes forming toxic epoxide by bromobenzene as well as on glutathione content. However, both methanol extract and isorhamnetin $3-O-{\beta}-D-glucopyranoside$ significantly recovered the decreased activities of glutathione s-transferase and epoxide hydrolase, and also reduced the lipid peroxide level in rats treated with bromobenzene. From the results, the protections of this plant against bromobenzene-induced hepatotoxicity are thought to be via enhancing the activities of epoxide hydrolase and glutathione s-transferase, enzymes removing toxic epoxide, and reducing the lipid peroxide level.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.444-450
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• 2007

The antioxidant activity and isoflavone content of chokong, Rhynchosia nolubilis seeds pickled in vinegar at $4^{\circ}C$ for 2 weeks, were investigated. The polyphenol content and 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical-scavenging capacity were lower in chokong than in raw seeds. Based on isoflavone analysis, the aglycone (daidzein and genistein) content was high in chokong while the content of the corresponding glucosides (daidzin and genistin) was similar to that in raw seeds. Thermal processing, in which seeds were heated in vinegar at $121^{\circ}C$ for 20 min, reduced the polyphenol content but did not affect the DPPH radical-scavenging capacity compared to the pickling process. The heated seeds had a 2.6 to 2.7 times higher glucoside content and 51 to 55% lower aglycone content than chokong, depending on the kind of vinegar used. During pickling and thermal processing, vinegars were more effective at eluting antioxidants and isoflavones from seeds than other solutions such as acetic acid, citric acid and HCl solutions, distilled water, and phosphate buffer (pH 7.0).