• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.3
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• pp.210-212
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• 2003

Recombinant $\beta$-glucosidase from Thermus caldophilus GK24 was easily purified partially by a heat treatment procedure, resulting in 8-fold and recovery yield of 80% from crude enzyme. When the $\beta$-glucosidase was incubated with a 80% glucose solution (w/w), gentiobiose ($\beta$1,6-glucobiose) was the major product in the reaction mixture. The optimal conditions for producing gentiobiose (11% yields of total sugar) were pH 8-9 and 7$0^{\circ}C$ for 72 h.

• Korean Journal of Microbiology
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• v.36 no.1
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• pp.8-13
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• 2000

We have examined the mode of transglycosylation, catalyzed by an extracellular $\beta$-glucosidase purified from Trichoderma koningii ATCC 26113, using cellobiose, sophorose, laminaribiose and gentiobiose as substrates. The dimers separated from the reaction mixture by HPLC were analyzed by $^(1)H$-NMR spectroscopy. When cellobiose was subjected to the action of the $\beta$-glucosidase, the products included laminaribiose, sophorose and gentiobiose. When laminaribiose, sophorose or gentiobiose was used as a substrate, the $\beta$-glucosidase accumulated transglycosylation products possessing different types of $\beta$-glycosidic linkages from the original one. The amount of dimers accumulated as reaction proceeded seemed to be dependent on the velocity of hydrolysis but not on that of formation.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.179-186
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• 1998

Dextransucrase hyper-producing Leuconostoc mesenteroides B-512FMCM and dextransucrase constitutive mutants B-742CB and B-1355C catalyzed the transfer of glucose from sucrose to other carbohydrates which were present or were added to the reaction digests. When the acceptor was a maltose, gentiobiose, lactose or raffinose, there was produced a series of oligosaccharide acceptor products or single product based on the kinds of enzymes and reaction conditions. To obtain the quantitative information about the yield and the distribution of acceptor products and dextran two experimental parameters were studied: a) the ratio of acceptor to sucrose and b) the amount of enzyme at constant carbohydrate concentration (100 mM). As the amount of enzyme increased, the synthesis of acceptor products (of maltose or gentiobiose) increased, and the formation of dextran decreased. As the ratio of acceptor to sucrose increased, the amount of dextran and the number of acceptor-products decreased and the amount of acceptor-products increased. When maltose or gentiobiose was an acceptor, the glucose from sucrose was transferred to the C-6 hydroxyl group of the nonreducing-end glucose residue of accepters to give a homologous series of isomaltosyl dextrins. In case of lactose or raffinose, there was produced only one acceptor product from B-512FMCM dextransucrase reaction. In the lactose acceptor reaction, the glucose from sucrose was transferred to the C-2 hydroxyl of the reducing end glucose residue of lactose. To get a series of oligosaccharides from lactose or raffinose acceptor reaction we used B-742CB dextransucrase or B-1355C alternansucrase with 500 mM sucrose in reaction digest.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.126-130
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• 1989

In 14 kinds of ginsenosides in ginseng saponin, ginsenoside Rbr is contained the most abundantly. But ginsenoside Rd which is similar to ginsenoside R $b_1$in structure, was known to be superior to ginsenoside R $b_1$pharmaceutically. The convertible enzyme which can transform ginsenoside R $b_1$to Binsenoside Rd specifically among ginseng saponin, was purified homogeneously from Rhizopus japonicus. The optimal pH for the action of the enzyme was pH 4.8 to 5.0, and optimal temperature was 45$^{\circ}C$. The enzyme was stable in the range of pH 4.0 to 9.0, and the half activity of enzyme was remained by the thermal treatment at 6$0^{\circ}C$ for 2 hours. The enzyme activity was enhanced by addition of M $n^{++}$ or Fe, though inhibited by EDTA or o-phenanthroline. On the substrate specificity, the enzyme was. able to hydrolyze gentiobiose, cellobiose, amygdalin and prunasin, but not to hydrolyze any other kinds of Binsenosides besides Binsenoside R $b_1$. Km values of the enzyme for ginsenoside R $b_1$, gentiobiose and amygdalin were 5.0mM, 4.8mM and 3.7mM, respectively.3.7mM, respectively.y.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.106-111
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• 2003

A novel carbohydrolase, which is a DXAMase, containing both dextranase and amylase equivalent activities, was purified from Lipomyces starkeyi KSM22. The purified DXAMase was also found to hydrolyze cellobiose, gentiobiose, trehalose and melezitose, while disproportionation reactions were exhibited with various di- and tri-saccharides, such as maltose, isomaltose, gentiobiose, kojibiose, sophorose, panose, maltotriose, and isomaltotriose with various kinds of oligosaccharides produced as acceptor reaction products. Furthermore, the purified DXAMase hydrolyzed raw waxy rice Starch and produced maltodextrin to the extent of 50% as a glucose equivalent.

• Journal of Life Science
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• v.34 no.2
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• pp.138-144
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• 2024

Crocin is a major carotenoid of the Gardenia jasminoides fruit and Crocus sativus stigma (saffron), which are used in various cuisines as flavoring and coloring agents, as well as in phytomedicine for the treatment of several disorders, including headache, fever, edema, fatty liver, viral hepatitis, respiratory disease, menstruation disorders, insomnia, and hypertension. Crocin (C₄₄H₆₄O₂₄) is a chemical diester composed of the dicarboxylic acid crocetin and disaccharide gentiobiose. Many in vitro and in vivo studies have been conducted about the biological and pharmacological function and toxicity of crocin. Crocin has been revealed to have no genotoxicity and pathological manifestation. Crocin acts as an antioxidant, anti-cancer, memory enhancer, anxiolytic, antidepressant, aphrodisiac, anti-atherosclerotic, cardioprotector, and hepatoprotector. Here, an inclusive review of crocin is introduced based on previously explored studies referred to in the literature. Different studies have confirmed the protective role of crocin in the pathogenesis of inflammatory diseases, including inflammatory bowel diseases, gastritis, asthma, atherosclerosis, rheumatoid arthritis, multiple sclerosis, type 1 diabetes, Alzheimer's disease, Parkinson's disease, and depression. It is surmised that crocin suppresses inflammatory, antioxidant, and apoptotic processes through multiple mechanisms. Crocin is considered a safe and effective therapeutic choice for patients with inflammatory conditions, although more research investigating its mechanisms and results acquired in clinical trials are needed.

• Journal of the Korean Wood Science and Technology
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• v.35 no.5
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• pp.100-108
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• 2007

$\beta$-Glucosidase from Laetiporus sulphureus among the enzymes related to lignocellulosic biomass degradation to sugars for using alternative bioethanol production was characterized. The highest activity of $\beta$-glucosidase was obtained on cellobiose at shaking culture. For the characterization and purification of $\beta$-glucosidase culture solution was concentrated and then purified by FPLC using ion exchange and size exclusion column. According to the results of SDS-PAGE, native PAGE and microfluidic system of purified enzyme, protein band was observed at about 132 kDa. Optimal pH and temperature of purified $\beta$-glucosi-dase were 5.0 and $60^{\circ}C$, respectively. In the kinetic properties of $\beta$-glucosidase on various substrates such as sophorose, gentiobiose and cellobiose, $K_m$ was 0.81, 1.07 and 1.70 mM, respectively.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.35-42
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• 1989

The mode of transglycosylation reaction observed during the action of low-molecular-weigh $\beta$-D-glucosidase ($\beta$-D-glucoside glucohydrolase, EC3.2.1.21) purified from Trichoderma koningii ATCC 26113 was investigated using $^{1}H$-NMR spectroscopy. The enzyme was purified by the series of procedures including ammonium sulfate precipitation, and fractionations by column chromatographies on Bio-Gel P-150, DEAE-Sephadex A-50, and SP-Sephadex C-50. The final purification was performed by the band eluation after preparative polyacrylamide gel electrophoresis. The enzyme showed its molecular size of 78,000 through the analysis of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its isoelectric point of 5.80 through the analysis of analytical isoelectric focusing. The H-1 proton resonances were analyzed. After the reaction of the enzyme with cellobiose, the reaction products were separated by high performance liquid chromatography using refractive index detector. H-1 resonances of the products were consisted with those of gentiobiose [$\beta$-D-glucopyranosyl--(1,6)-D-glucopyranose], and cellotriose [$\beta$-D glucopyranosyl-(1,4)-$\beta$-D-glucopyranosyl]-(1,4)-D-glucopyranose] with minor resonances of sophorose [$\beta$-D-glucopyranosyl-(1,2)-D-glucopyranose], respectively.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.251-262
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• 1986

High-molecular-weight ${\beta}-glucosidase$ (EC 3.2.1.21) was purified from the culture filtrate of Trichoderma koningii through a four-step procedure including chromatography on Bio-Gel P-150, DEAE-Sephadex A-50 and SP-Sephadex C-50; and chromatofocusing on Polybuffer exchanger PBE 94. The molecular weight of the enzyme was determined to be about 101,000 by SDS-polyacrylamide gel electrophoreses, and the isoelectric point was estimated to be 4.96 by analytical isoelectric focusing. The temperature optimum for activity was about $55^{\circ}C$, and the pH optimumwas 3.5. The enzyme was considerably thermostable, for no loss of activity was observed when the enzyme was preincubated at $60^{\circ}C$ for 5h. Km values for cellobiose, gentiobiose, sophorose, salicin and $p-nitrophenyl-{\betha}-D-glucoside$ were 99.2, 14.7, 7.09, 3.15 and 0.70 mM, respectively, which indicates that the enzyme has much higher affinity towards $p-nitrophenyl-{\betha}-D-glucoside$ than towards the other substrates, especially cellobiose. Substrate inhibition by $p-nitrophenyl-{\betha}-D-glucoside$ and salicin was observed at the conecntrations exceeding 5mM. Gluconolactone was a powerful inhibitor against the action of the enzyme on $p-nitrophenyl-{\betha}-D-glucoside\;(K_i\;37.9\;{\mu}M)$, wherease glucose was much less effective ($K_i$ 1.95 mM). Inhibition was of the competitive type in each case. Transglucosylation activity was detected shen the readtion products formed from $p-nitrophenyl-{\betha}-D-glucoside$ by the enzyme were analysed using high-performance liquid chromatography.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.454-460
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• 2007

Enzymatic properties and substrate specificity of recombinant $\beta-glycosidases$ from a hyperthermophilic archaeon, Sulfolobus shibatae (rSSG), were analyzed. rSSG showed its optimum temperature and pH at $95^{\circ}C$ and pH 5.0, respectively. Thermal inactivation of rSSG showed that its half-life of enzymatic activity at $75^{\circ}C$ was 15 h whereas it drastically decreased to 3.9 min at $95^{\circ}C$. The addition of 10 mM of $MnCl_2$ enhanced the hydrolysis activity of rSSG up to 23% whereas most metal ions did not show any considerable effect. Dithiothreitol (DTT) and 2-mercaptoethanol exhibited significant influence on the increase of the hydrolysis activity of rSSG rSSG apparently preferred laminaribiose $(\beta1\rightarrow3Glc)$, followed by sophorose $(\beta1\rightarrow2Glc)$, gentiobiose $(\beta1\rightarrow6Glc)$, and cellobiose $(\beta1\rightarrow4Glc)$. Various. intermolecular transfer products were formed by rSSG in the lactose reaction, indicating that rSSG prefers lactose as a good acceptor as well as a donor. The strong intermolecular transglycosylation activity of rSSG can be applied in making functional oligosaccharides.