• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1993년도 학술대회지
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• pp.74-83
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• 1993

In an attempt toward the synthesis of the difficulty accessible ginseng saponins the four dammarane glycosides identical to the natural $ginsenosides-Rh_2,$ - F2, compound K and chikusetsusaponin - LT8 have been prepared from betulafolienetriol(=dammar-24-ene-$3{\alpha},12{\beta}\;20(S)-triol).\;3-O-{\beta}-D-Glucopyranoside$ of 20(S) - protopanaxadiol $(=ginsenoside-Rh_2)$ have been obtained by the regio - and stereoselective glycosylation of the $12-O-acetyldammar-24-ene-3{\beta},\;12{\beta},$ 20(S)-triol. The 12-ketoderivative of 20(S)-protopanaxadiol has been used as aglycon in synthesis of chikusetsusaponin - LT8. Attempted regio - and stereoselective glycosylation of the less reactive tertiary C - 20 - hydroxyl group in order to synthesize the $20-O-{\beta}-D-glucopyranoside$ of 20(S)-protopanaxadiol(=compound K) using 3, 12 - di - O - acetyldammar - 24 - ene - $3{\beta},12{\beta},20(S)$-trial as aglycon was unsuccessful. Glycosylation of 3, 12 - diketone of betulafolienetriol followed by $NaBH_4$ reduction yielded the $20-O-{\beta}-D-glucopyranoside\;of\;dammar-24-ene-3{\beta},12{\alpha},$ 20(S)-triol, the $12{\alpha}-epimer$ of 20(S) - protopanaxadiol. Moreover, a number of semisynthetic ocotillol - type glucosides, analogs of natural pseudoginsenosides, have been prepared.

• Archives of Pharmacal Research
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• 제25권3호
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• pp.289-292
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• 2002

The ethyl acetate extract of the leaves of Ixeris sonchifolia afforded two new and two known sesquiterpene lactone glucosides of the guaiane-type, together with a known alkenol glucoside. The known compounds were identified as ixerin Z (1), ixerin Z-6'-p-hydroxyphenylace-tate (2), and (Z)-3-hexen-1-ol-$\beta$-D-glucopyranoside (3), respectively. The structures of the new compounds were elucidated as 11, 13a-dihydroixerin Z [4, 3-hydroxy-2-oxo-guaia-1 (10), $3-dien-5{\alpha},6{\beta},7{\alpha},11{\beta}H-12,6-olide-3-O-{\beta}-D-glucopyranoside],{\;}and{\;}3,10{\$beta}-dihydroxy-2-oxo-guaia-3,11(13)-dien-1{\alpha},5{\alpha},6{\alpha},7aH-12,6-olide-10-O-{\beta}-D-glucopyranoside$ (5), respectively. The cytotoxicity of these compounds against human hepatocellular carcinoma cell (HepG2) and human melanoma cell (SK-MEL-2) was evaluated.

• 한국미생물·생명공학회지
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• 제49권2호
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• pp.174-180
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• 2021

Chalcones exhibit multiple biological activities. Various studies have attempted to modify the structure of chalcones with a special focus on the addition of substituents to the benzene rings. However, these chemical modifications did not improve the water solubility and bioavailability of chalcones. Glycosylation can markedly affect the physical and chemical properties of hydrophobic compounds. Here, we evaluated the ability of a highly promiscuous glycosyltransferase (GT) BsGT1 from Bacillus subtilis ATCC 6633 to biosynthesize chalcone glucosides. Purified BsGT1 catalyzed the conversion of 4'-hydroxychalcone (compound 1), 4'-hydroxy-4-methylchalcone (compound 2), and 4-hydroxy-4'-methoxychalcone (compound 3), into chalcone 4'-O-β-D-glucoside (compound 1a), 4-methylchalcone 4'-O-β-D-glucoside (compound 2a), and 4'-methoxychalcone 4-O-β-D-glucoside (compound 3a), respectively. To avoid the addition of expensive uridine diphosphate glucose (UDP-Glc), a whole-cell biotransformation system was employed to provide a natural intracellular environment for in situ co-factor regeneration. The yields of compounds 1a, 2a, and 3a were as high as 90.38%, 100% and 74.79%, respectively. The successful co-expression of BsGT1 with phosphoglucomutase (PGM) and UDP-Glc pyrophosphorylase (GalU), which are involved in the biosynthetic pathway of UDP-Glc, further improved the conversion rates of chalcones (the yields of compounds 1a and 3a increased by approximately 10%). In conclusion, we demonstrated an effective whole-cell biocatalytic system for the enzymatic biosynthesis of chalcone β-D-glucoside derivatives.

• KSBB Journal
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• 제11권5호
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• pp.511-517
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• 1996

본 연구에서는 친수성기질과 소수성기질을 함께 수용하는 수용성 상용용매를 사용하여 반응매질의 친수성과 소수성이 알킬글루코시드의 합성반응에 적 합하도록 조절된 양친매질을 개발하고 hydrophili C city control이 이루어진 효소반응기술을 이용하여 효소의 활성도와 안정성, 기질의 가용화, 얄킬글루코 시드의 수율과 농도의 관점에셔 가장 바람직한 양친 매상 효소반응공정 (amphiphilic phase enzyme re action process)을 제시하였으며, 핵실글루코시드, 옥틸글루코시드, 데실글루코시드 및 도데실글루코시 드를 합성한 결과 생생물 농도는 각각 18.2, 9.68, 7.27, 6.03g/L을 얻였다.

• Food Science and Biotechnology
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• 제18권2호
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• pp.294-298
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• 2009

Distribution of isoflavones and fatty acids in soymilk fermented with 7 Lactobacilli (L-type), 7 Bifidobacteria (B-type), or 5 Streptococci (S-type) were monitored. Total isoflavones in fermented soymilk ranged from 5.24 to $8.59{\mu}mol/g$ dry basis while those in unfermented soymilk were $8.06{\mu}mol/g$ dry basis. Depending on the types of inoculated microorganisms, fermented soymilk showed different profiles in isoflavones, especially aglycones and $\beta$-glucosides. Four L-type fermented soymilk had significantly higher aglycone content (33.69-46.21%) and low $\beta$-glucosides compared to control (p<0.05). All B-type fermented soymilk showed significantly high aglycone levels (p<0.05). Out of 5 Streptococci, 4 strains produced over 82.2% aglycones. Lipid content ranged from 162 to 224 mg/g and linoleic acid was the highest, followed by oleic, linolenic, palmitic, and stearic acids. Average ratio of unsaturated to saturated fatty acids in control, L-, B-, and S-type fermented soymilks was 6.30, 6.09, 6.30, and 5.94, respectively. This study can help to develop a fermented soymilk containing high isoflavone aglycones and low fat content.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.636-639
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• 2002

The extract of the root of Polygonum multiflorum exhibited a significant antioxidant activity assessed by the DPPH radical scavenging activity in vitro. The bioassay-guided fractionation of the extract yielded a stilbene glucoside, (E)-2,3,5,4'-tetrahydroxystilbene-2-Ο-$\beta$-d-glucopyranoside (1) as an active constituent responsible for the antioxidant property. Compound 1 demonstrated a moderate DPPH radical scavenging activity ($IC_{50}$, 40 $\mu$M), while the corresponding deglucosylated stilbene 2 exhibited a much higher activity ($IC_{50}$, 0.38 $\mu$M).

• 한국식품영양과학회지
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• 제45권5호
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• pp.702-710
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• 2016

본 연구는 ${\beta}$-glucosidase 활성이 있는 Bacillus subtilis HJ18-9와 HJ25-8, 두 가지 균주를 혼합한 HJ18-9+HJ25-8의 3가지 균주를 스타터로 접종하여 발효시킨 soy grits 청국장의 품질 특성과 isoflavone의 함량을 측정하였다. 환원당을 유리하는 데 관여하는 ${\alpha}$-amylase 효소 활성의 경우 두 가지 균주를 혼합한 HJ18-9+HJ25-8을 접종해 발효한 시료에서 다른 시료와 비교하였을 때 높은 활성을 보였다. 청국장의 단백질을 분해하여 특유의 구수한 맛 성분을 유리하는 protease 활성의 경우 HJ25-8, HJ18-9+HJ25-8, HJ18-9의 순으로 높은 활성을 나타내었다. 또한 아미노태 질소와 암모니아태질소의 함량은 HJ25-8을 접종해 발효한 SG 청국장에서 높았으며, 청국장 isoflavone 비배당체 함량은 HJ18-9+HJ25-8의 $272.40{\pm}2.04{\mu}g/g$에 비해 HJ18-9와 HJ25-8 접종구에서 $697.03{\pm}9.46$, $683.10{\pm}2.05{\mu}g/g$으로 높았다. ${\beta}$-glucosidase 활성이 있는 두 가지 균의 혼합으로 isoflavone aglycone 함량의 전환율을 더 높일 수 있는 시너지 효과를 기대했으나 단일 균주로 접종하여 발효했을 때 더 높은 aglycone 함량을 얻을 수 있었다. 본 연구를 통해 청국장 제조에 알맞은 균주를 개발 평가하여 청국장 가공품 개발의 기초연구가 되고자 하였다.

• Journal of Microbiology and Biotechnology
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• 제1권3호
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• pp.188-196
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• 1991

The ${\beta}-glucosidase$ was purified to homogeneity from the culture filtrate of P. verruculosum by column chromatography. The enzyme was a glycoprotein with a relative size of approximately 220 kDa with an isoelectric point of 4.8, which was composed of dimeric protein of 105 kDa. The enzyme was stable up to $60^{\circ}C$ and the presence of glycerol significantly increased its thermostability. The enzyme was found to hydrolyze both ${\beta}-aryl$ and ${\beta}-alkyl-glucosides$ in addition to ${\beta}-glucosyl$ glucose and catalyzed glucosyl transfer to cellobiose. The enzyme attacked laminarin in an exotype-like fashion. The apparent Km's of the enzyme toward cellobiose, laminaribiose, laminarin were 0.53 mM, 0.35 mM and 1.11 mM, respectively. Glucose and glucono-${\delta}-lactone$ were competitive inhibitors for the enzyme. Copper ($Cu^{2+}$), mercury ($Hg^{2+}$) and p-chloromercuribenzoate were strong inhibitors of the enzyme. The immunoblotting result revealed that one form of ${\beta}-glucosidase$ was biosynthesized, irrespective of carbon sources used. Polyacrylamide gel electrophoresis analysis of the in vitro translated product of total RNA from avicel grown mycelium established that the P. verruculosum ${\beta}-glucosidase$ precursor was approximately 95 kDa in size. The amino acid composition and N-terminal amino acid sequence are given.

• Applied Biological Chemistry
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• 제49권2호
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• pp.149-152
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• 2006

산겨릅나무(A. tegmentosum)의 성분 연구를 위하여 줄기를 MeOH로 추출하여 $CH_2Cl_2$, n-BuOH 및 $H_2O$ 순으로 분획하였다. n-BuOH fraction에 대하여 silica gel과 RP-18 column chromatography를 행하여 2종의 화합물을 분리하였다. 이들 화합물의 구조는 spectral data를 문헌치와 비교하여 methyl gallate $4-O-{\beta}-D-glucoside(1)$와 salidroside(2)로 동정하였다. 이들 화합물은 산겨릅나무에서 처음으로 분리되었다.

• 생약학회지
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• 제24권4호
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• pp.282-288
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• 1993

Very little utilization of the fruits of Malus baccata(Rosaceae) has been employed for food and medicinal plants except for preparing fruit beverages. But, it was estimated as valuable to investigate the chemical components for the botanical resource of this plant. In this study, it was found that the fruits of this plant contained primary long chain alcohol, ${\beta}-sitosterol$, campesterol, ursolic acid and ${\beta}-_D-glucosides$ of ${\beta}-sitosterol$ and campesterol. However, phloretin(dihydrochalcone) and its 5-O-glucoside(phloridzin) known as plant growth regulators in many Rosaceae plants were not found in this plant material by co-TLC analysis with authentic specimens. Although plant sex hormone, estrone, was often contained in relates of M. baccata, e.g., Prunus spp., Crataegus spp. and Malus spp., this compound was not detected in this fruit by comparison with an authentic material. By RIC chromatography, it was suggested that the Soxhlet extraction by the solvent of ether was excellently useful to extract ursolic acid efficiently.