• Biotechnology and Bioprocess Engineering:BBE
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• 제8권3호
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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.

• 미생물학회지
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• 제36권1호
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• pp.8-13
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• 2000

Trichoderma koningii ATCC 26113에서 분비되는 효소인 $\beta$-glucosidase를 cellobiose, sophorose, laminaribiose 및 gentiobiose 등의 기질과 반응시킨 후 효소의 transglycosylation 반응 산물을 분석하였다. 각각의 기질로부터 생성된 이당체(dimer)들을 HPLC로 분리하고 $^(1)H$-NMR spectroscopy를 통하여 분석하였다. Cellobiose를 기질로 사용하여 효소와 반응시켰을 때 그 산물에는 laminaribiose, sophorose 및 gentiobiose가 포함되었음을 확인할 수 있었다. Laminaribiose, sophorose 및 gentiobiose를 기질로 사용하였을 경우에 효소는 transglycosylation 반응을 통하여 새로운 $\beta$-glycosidic 결합을 갖는 이당체들을 생성하였다. 효소반응에 의하여 누적되는 이당체의 양은 생성속도보다는 분해속도에 의하여 결정되는 것으로 나타났다.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.179-186
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• 1998

본 연구에서는 dextransucrase hyper-producing Leuconostoc mesenteroides B-512FMCM과 dextransucrase constitutive mutants인 B-742CB 및 B-1355C에서 얻은 dextransucrase 및 alternansucrase를 이용하여 maltose, lactose, gentiobios 및 raffinose의 수용체반응을 수행하였다. B-512FMCM의 경우 수용체로서 maltose와 gentiobiose는 설탕에 대한 농도비가 1/1이하일 때 수용체에 ${alpha}$l-6으로 D-glucose가 결합한 일련의 올리고당을 생성하였고, 9/1이상에서는 단 두 가지의 수용체산물로서 maltose의 경우에는 panose와 isomaltosyl maltose를, gentiobiose의 경우에는 6$^2$-${alpha}$-D-glucopyranosyl gentiobiose와 isomaltosyl gentiobiose만을 생성하였다. 그러나 lactose는 유일한 산물인 2$^1$-${alpha}$-D-glycopyranosyl lactose만을 생성하였다. 효소양의 변화에 대해서 maltose와 gentiobiose의 수용체반응에서 생성된 수용체산물(올리고당)의 수와 양은 효소양이 증가함에 따라 증가하였으나 lactose의 경우에는 효소양의 증가에 대해 수용체산물 양의 변화가 크지 않았다. B-742CB dextransucrase와 B-1355C alternansucrase를 사용하면 B-512FMCM dextransucrase에서는 단 한가지만의 수용체산물을 생산하였던 lactose와 raffinose를 수용체로 하여 여러 가지의 수용체산물(올리고당)을 생산하였다.

• 한국미생물·생명공학회지
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• 제17권2호
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• pp.126-130
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• 1989

인삼 saponin 중에서 조성 비율이 가장 큰 ginsenoside R $b_1$을 약효면에서 훨씬 우수한 ginsenoside-Rd로 선택적 전환할 수 있는 전환효소를 Rhizopus japonicus 배양물로부터 순수하게 정제한 후 그 효소학적 특성을 조사하였다. 본 효소는 pH 4.8~5.0, 45$^{\circ}C$에서 그 활성도가 가장 높았으며 pH4~9의 범위에서 안정하였고, pH5.0에서 6$0^{\circ}C$ 열처리할 경우 50% 실활하는데 2시간이 소요되었다. M $n^{++}$, F $e^{++}$에 의해 효소활성이 촉진되었으며 C $u^{++}$, A $g^+$에 의해서는 저해되었다. 효소 저해제중에는 EDTA, o-phenanthroline 등에 의해 저해되기도 했다. 본 효소는 당류중에는 gentiobiose, cellulose만을, glycoside 중에서는 amygdalin, purnasin, salicin 등을 분해할 수 있었으며 ginsenoside R $b_1$, 이외의 다른 ginsenoside는 전혀 분해할 수 없었다. 본 효소의 Km치는 total saponin 기질 및 ginsenoside Rb group saponin 기질은 ginsenoside R $b_1$으로서 5.0mM 이었으며, gentiobiose는 4.8mM, amygdalin은 3.7mM 이었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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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.

• 생명과학회지
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• 제34권2호
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• pp.138-144
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• 2024

Crocin은 여러 가지 요리에 향미와 색깔을 주는 치자 열매나 사프란에 함유되어 있는 적노란색의 수용성 색소이다. 사프란과 치자는 전통의학 분야에서 부종, 해열, 해독 작용이 있어 바이러스성 간염, 식도염, 관상동맥심장병, 신경쇠약, 불면증, 퇴행성 신경질환, 호흡기 질환, 비뇨기 질환 등을 치료하는데 사용되어 왔다. Crocin (C₄₄H₆₄O₂₄)은 카로테노이드의 복합체로, dicarboxylic acid crocetin과 disaccharide gentiobiose로 이루어진 diester이다. Crocin은 혈액학적인, 병리학적인 독성이나 유전독성이 없다. 현재까지 수많은 생체 내 및 생체 외 연구들을 통해 Crocin의 생물학적인 약리작용이 밝혀지고 있다. 본 총설에서는 염증성 장질환, 위염, 천식, 동맥경화, 류머티스 관절염, 다발성 경화증, 당뇨, 알츠하이머병, 파킨슨병, 우울증 등의 염증 관련 질환에서 Crocin의 보호 효과를 요약한다. Crocin은 다양한 작용 기전을 통해 항염, 항산화, 세포 자살 방지 기능을 함으로써 이들 질환을 개선하는 것으로 추론된다.

• Journal of the Korean Wood Science and Technology
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• 제35권5호
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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.

• 미생물학회지
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• 제27권1호
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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.

• 미생물학회지
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• 제24권3호
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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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• 제17권3호
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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.