• 한국미생물·생명공학회지
• /
• 제37권2호
• /
• pp.99-104
• /
• 2009

Streptomyces coelicolor A3(2)의 $\beta$-glucosidase 유전자를 분리하여 대장균에서 발현하여 특성을 조사하였다. 최적 활성을 나타내는 온도는 pH 5에서는 $20^{\circ}C$, pH 6에서는 $60^{\circ}C$에서 높은 활성을 나타냈다. pH에 따른 활성은 pH 3 이하와 pH 9 이상의 범위에서는 낮은 활성을 나타냈으며 pH 7에서 가장 높은 활성을 나타냈다. $\alpha$-pNPG($\rho$-nitrophenyl-$\alpha$-D-glucopyranoside), $\beta$-pNPG ($\rho$-nitrophenyl-$\beta$-D-glucopyranoside), $\beta$-pNPF($\\rho$-nitrophenyl-$\beta$-D-fucopyranoside)는 pH 3-10까지 비슷한 활성을 나타냈으며, $\alpha$-pNPG가 pH 7에서 다소 높은 활성을 보였다. $\beta$-pNPGA는 pH 5-9까지 높은 활성을 나타냈으며, 특히 pH 9에서 3배 이상의 높은 활성을 나타냈다. 기질 $\alpha$-pNPG, $\beta$-pNPG, $\beta$-pNPF의 온도에 따른 활성변화는 $\beta$-pNPF의 활성이 $60^{\circ}C$에서 증가하였고, $\beta$-pNPGA는 $30-50^{\circ}C$까지 활성이 증가하여 $50^{\circ}C$에서 최대활성을 나타내었다. 당화 flavonoid를 이용한 기질특이성의 상대활성은 daidzin, glycitin, genistin, 순으로 나타났으며 esculin과 apigenin-7-glucose는 기질로 사용하지 않았다. $\beta$-Glucosidase 활성은 EDTA, DTT에 의해 억제되었으며, $MnSO_4$, $CaCl_2$, KCl, $MgSO_4$에 의해 증가하였고, 특히 Mn이온에 의해 증가하였다. $CuSO_4$, NaCl에 의해 효소활성이 저해되었으며, 특히 $ZnSO_4$의 경우 효소활성이 강하게 억제되었다.

• Journal of Microbiology and Biotechnology
• /
• 제18권5호
• /
• pp.933-941
• /
• 2008

An extracellular $\beta$-glucosidase produced by Monascus purpureus NRRL1992 in submerged cultivation was purified by acetone precipitation, gel filtration, and hydrophobic interaction chromatography, resulting in a purification factor of 92-fold. A $2^2$ central-composite design (CCD) was performed to find the best temperature and pH conditions for enzyme activity. Maximum activity was observed in a wide range of temperature and pH values, with optimal conditions set at $50^{\circ}C$ and pH 5.5. The $\beta$-glucosidase showed moderate thermostability, was inhibited by $HgCl_2$, $K_2Cr_O_4$, and $K_2Cr_2O_7$, whereas other reagents including $\beta$-mercaptoethanol, SDS, and EDTA showed no effect. Activity was slightly stimulated by low concentrations of ethanol and methanol. Hydrolysis of p-nitrophenyl-$\beta$-D-glucopyranoside (pNPG), cellobiose, salicin, n-octyl-$\beta$-D-glucopyranoside, and maltose indicates that the $\beta$-glucosidase has broad substrate specificity. Apparently, glucosyl residues were removed from the nonreducing end of p-nitrophenyl-$\beta$-D-cellobiose. $\beta$-Glucosidase affinity and hydrolytic efficiency were higher for pNPG, followed by maltose and cellobiose. Glucose and cellobiose competitively inhibited pNPG hydrolysis.

• Journal of Microbiology and Biotechnology
• /
• 제12권1호
• /
• pp.8-13
• /
• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• 산업식품공학
• /
• 제15권3호
• /
• pp.214-220
• /
• 2011

중고압 하에서 $\beta$-glucosidase효소반응을 물리화학적 관점에서 연구하였다. 모델 기질 (p-nitrophenyl-${\beta}$-D-glucopyranoside)에 대한 $\beta$-glucosidase 효소의 작용에 대한 압력 효과를 실험 하였다. 즉, 압력 조건(25MPa, 50 MPa, 75 MPa, 100 MPa)과 시간 (10분, 60분, 1시간, 6시간, 24시간, 40시간)의 처리 조건에서 효소 활성도를 분광학적인 표준방법에 따라 측정하였다. 효소-기질 반응의 단계를 크게 kinetic 구간과 평형 구간으로 구분하여 물리화학적 모델을 적용하여, 정 역반응속도 상수, 평형상수, 압력에 의한 부피 감소 등을 산출하였다. 대기압에서 100MPa까지 압력이 증가할수록 효소-기질 반응의 생성물이 더 많이 형성되었으며 전형적인 kinetic 구간과 평형 구간이 나타났다. 압력, 시간, 생성물농도 등의 데이터로부터 kinetic 구간과 평형에서의 생성물 예측 모델을 완성하였다. 결론적으로 중고압 처리에 의하여 효소-기질 반응이 촉진됨을 알 수 있었고, 임의의 압력 및 시간 조건에 따른 생성물의 농도를 예측할 수 있게 되었다.

• KSBB Journal
• /
• 제6권2호
• /
• pp.147-156
• /
• 1991

Diazotized chitin (CHITN) was synthesized reacting with NaN3 and HCl to alkaline hydrolyzed chitin for the support of immobilized enzyme. Immobilized $\beta$-glucosidase on diazotized chitin(CHITN-Gase) was produced reacting with glutaraldehyds as bifunctional reagent. CHITN-Gase activities were determined reacting with p-nitrophenol-$\beta$-D-glucopyranoside in plug flow reactor as a reference. Optimum temperature, optimum pH, reaction constant and deactivation rate were determined with variation of flow rate and H/D. The particle size of immobilized enzyme in the best was, 35 mesh (CHITN35-Gase). The optimum conditions of immobilized enzyme were $70^{\circ}C$ in temperature and 5.0 in pH. Diameter and flow rate of plug flow reactor in the best was 8.5mm in diameter and 0.8ml/min in flow rate. Reaction constant was mainly influenced by electrostatic force. The best glucose hydrolizing activities of CHITN3 5-Gase was 3.34$\times$10-5 M/1. while that of native-$\beta$-glucosidase was 2.44$\times$10-5 M/1.

• 미생물학회지
• /
• 제27권1호
• /
• pp.35-42
• /
• 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.

• Journal of the Korean Wood Science and Technology
• /
• 제38권3호
• /
• pp.251-261
• /
• 2010

Formiptosis pinicola KMJ812에 의해 생산된 조효소액은 섬유소 분해효소 복합체로서 매우 활성이 높으며 특히 ${\beta}$-glucosidase의 활성이 높아 포도당 전환수율이 높다. 본 연구에서는 F. pinicola KMJ812 생산 cellulase를 고정화에 따른 효소특성의 변화와 고정화 효소의 재사용에 따른 효소의 불활성 정도를 관찰하였다. 담체는 고정화 수율이 cellulase활성 61.7%와 ${\beta}$-glucosidase활성 64.4%로 우수한 Duolite A568로 선정하였다. 고정화 효소의 최적반응온도는 cellulase와 ${\beta}$-glucosidase 활성의 경우 모두$55^{\circ}C$로서 수용성효소보다 높았으며, 최적 pH는 cellulase활성은 4.0이었고, ${\beta}$-glucosidase활성은 4.5로 cellulase활성의 경우에서만 수용성효소와 비교하여 약간 염기성으로 변화하였다. 본 고정화 효소는 $50^{\circ}C$에서 72시간 후에 98%의 활성을 유지하고 있었으며, $50^{\circ}C$에서 8회 사용 후에 50%정도의 잔존활성을 나타내었다.

• 한국동물학회지
• /
• 제32권3호
• /
• pp.290-303
• /
• 1989

$\beta$-glucosidase, $\beta$-glucuronidase, N-acetyl-$\beta$-glucosaminidase의 성적 성숙과의 연관서을 조사하기 위하여 흰쥐의 복강내로 testosterone과 dibutryjry cyclic AMP 를 투여하여 위이 효소들의 활성도를 측정하였다. 그 결과 겨세한 실험군에서$\beta$-glucosidase와 N-acetyl-$\beta$-glucosaminidase이 활성도도 거세후 7일째에는 유의성있는 감소효과를 나타내었다. testosterone을 7일간 계속 투여한 경우에는 세 효소의 활성도가 모두 유의성있게 증가하였고 dbcAMP 투여군의 경우는 거세 14일째되는 실험군과 비슷하거나 감소하는 경향이 있었다. 미세구조를 관찰한 결과 부정소 상피세포의 유형은 크게 주세포와 기저세포로 나눌 수 있었으며 주세포는 일반적인 원주상피의 형태를 나타냈으며 소낭을 많이 포함하고 있는 narrow cell이 존재하였다. 특히 부정소미에는 다른 상피세포에 비해 전자밀도가 낮은 light cell이 존재했고 기저세포는 부정소 부위마다 비슷한 형태를 가지는 것으로 나타났으며 상피세포 사이에는 이동능력을 가진 halo cell이 존재했다.

• Mycobiology
• /
• 제40권3호
• /
• pp.173-180
• /
• 2012

A ${\beta}$-glucosidase from Penicillium italicum was purified with a specific activity of 61.8 U/mg, using a chromatography system. The native form of the enzyme was an 88.5-kDa tetramer with a molecular mass of 354 kDa. Optimum activity was observed at pH 4.5 and $60^{\circ}C$, and the half-lives were 1,737, 330, 34, and 1 hr at 50, 55, 60, and $65^{\circ}C$, respectively. Its activity was inhibited by 47% by 5 mM $Ni^{2+}$. The enzyme exhibited hydrolytic activity for p-nitrophenyl-${\beta}$-D-glucopyranoside (pNP-Glu), p-nitrophenyl-${\beta}$-D-cellobioside, p-nitrophenyl-${\beta}$-D-xyloside, and cellobiose, however, no activity was observed for p-nitrophenyl-${\beta}$-D-lactopyranoside, p-nitrophenyl-${\beta}$-D-galactopyranoside, carboxymetyl cellulose, xylan, and cellulose, indicating that the enzyme was a ${\beta}$-glucosidase. The $k_{cat}/K_m\;(s^{-1}mM^{-1})$ values for pNP-Glu and cellobiose were 15,770.4 mM and 6,361.4 mM, respectively. These values were the highest reported for ${\beta}$-glucosidases. Non-competitive inhibition of the enzyme by both glucose ($K_i=8.9mM$) and glucono-${\delta}$-lactone ($K_i=11.3mM$) was observed when pNP-Glu was used as the substrate. This is the first report of non-competitive inhibition of ${\beta}$-glucosidase by glucose and glucono-${\delta}$-lactone.

• KSBB Journal
• /
• 제11권3호
• /
• pp.347-352
• /
• 1996

통시당화발효공정에 적용된 막분리 효소재순환 시스템을 이용하여 온도 및 압력 조건에 따른 효소역 가감소현상에 대해서 고찰하였다. 목질계바이오매스 를 기질로한 효소당화공정을 고려하여 사용된 효소인 cellulase와 ${\beta}$-glucosidase을 막분리 재순환 시킬 수 있는 최적의 막은 MWCO가 50,000인 한외여과 막이라 판단되었다. cellulase의 경우 한외여과막을 이용하여 연속적으로 재순환 시 켰을때, 효소역가의 감소를 확인할 수 없었다. 그러나 ${\beta}$-glucosidase는 온도와 압력이 증가할수록 초기상태를 기준으로 온도 $42^{\circ}C$, 투과압력 28.4 psig에서 최대 35%까지 감소함을 확인하였다. 이것은 온도와 압력이 중가할 수록 투과플럭스가 증가하고, 이에따른 막모률의 사(fiber) 내부표면에서 전단(shear)이 증가된 결과로 설명할 수 였다.