• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.788-794
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• 2014

An extracellular ${\beta}$-glucosidase from Aspergillus niger Au0847 was purified to homogeneity by precipitation with ammonium sulfate, anion exchange, and gel filtration. The purified protein was composed of two subunits with molecular masses of 110 and 120 kDa. Au0847 ${\beta}$-glucosidase exhibited relatively high thermostability and pH stability, and its highest activity was obtained at $65^{\circ}C$ and pH 4.6, respectively. As a potential metalloprotein, its enzymatic activity was potently stimulated by manganese ion and DTT. The ${\beta}$-glucosidase displayed avid affinity and high catalytic efficiency for geniposide. Au0847 ${\beta}$-glucosidase has potential value as an industrial enzyme for the hydrolysis of geniposide to genipin.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.933-941
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• 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.

• KSBB Journal
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• v.17 no.4
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• pp.381-387
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• 2002

A filamentous fungus, strain FB01 showing high $\beta$-glucosidase activity was isolated from a compost. This fungus was cocultured with Trichoderma viride to enhance the productivity of $\beta$-glucosidase by changing inoculation time of the fungus. The microbial consortium showed higher cellulolytic enzyme production than T. viride alone. The maximal enzyme production was obtained when the microbial consortium was cultured at 30$\^{C}$ and pH 6.0 for 10 days with the activities of CMCase, $\beta$-glucosidase, and avicelase of 2.0, 0.8, and 0.2 U/mL, respectively. These enzyme activities were 2, 4, and 2 times as high as those of CMCase, p-glucosidase, avicelase from T. viride, respectively, indicating that a synergistic interaction appeared between T. viride and strain FBOI . The serial subcultures with pH control increased $\beta$-glucosidase production about 3.2 times. Enzyme production using ricestraw as a carbon source showed that the activities of CMCase, $\beta$-glucosidase, and avicelase were 3.69, 0.76, 0.17 U/mL, respectively, and $\beta$-glucosidase activity was 1.5 times higher than that of T viride.

• KSBB Journal
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• v.11 no.3
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• pp.347-352
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• 1996

The enzyme deactivation in a membrane recycling system for the simultaneous saccharification and fermentation(SSF) was studied under various temperature and pressure. The optimum molecular weight cut off(MWCO) of the ultrafiltration membrane for recycling cellulase and ${\beta}$-glucosidase was 50,000. When the cellulase was recycled continuously through the membrane system, it was not deactivated. But the activity of ${\beta}$-glucosidase was decreased with an increase in operating temperature and transmembrane pressure. After 720 minutes at $42^{\circ}C$ and 24.8 psig , the activity of ${\beta}$-glucosidase was reduced by 35% of the initial activity. Such tendencies could be well explained by the results of highly induced shear at the fiber surface of membrane when temperature and transmembrane pressure became higher.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.260-266
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• 2009

The effects of ${\beta}$-glucosidase on the overall growth performance and a set of physiological parameters of broilers were investigated. 240 male, one-day old Avine broiler chickswere randomly allocated to four treatment groups and fed with a corn-soybean meal supplemented with 0% (control), 0.2%, 0.4% and 0.6% ${\beta}$-glucosidase. The 0.2% ${\beta}$-glucosidase group, but not the 0.4% and 0.6% ${\beta}$-glucosidase groups, showed a significantly increased average daily weight gain (p<0.05) over that of the control. All three ${\beta}$-glucosidase feed groups showed significantly higher feed conversion ratios than the control group (p<0.05). Feed supplementation of 0.2% ${\beta}$-glucosidase significantly raised the contents of serum isoflavone aglycones as shown by decreases of genistin and daizin (p<0.01) and an increase of daidzein (p<0.01). The 0.2% ${\beta}$-glucosidase feeding significantly increased the intestinal amylase activity while it had little effect on lipase and trypsin activities (p>0.05). 0.2% ${\beta}$-glucosidase feeding also significant elevated the levels of highdensity lipoprotein cholesterol and malate dehydrogenase while lowering the level of low-density lipoprotein cholesterol (LDL-C). Finally, ${\beta}$-glucosidase improved the anti-oxidative activities of the animals; the 0.2% ${\beta}$-glucosidase feed group had higher activities of superoxide dismutase (p<0.05), glutathione peroxidase and glutathione reductase in the liver (p<0.05), and malondialdehyde level in the serum (p<0.05).

• Korean Membrane Journal
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• v.8 no.1
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• pp.58-66
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• 2006

The ${\beta}-glucosidase$ from olive fruit is of particular interest compared to the ones from other sources because it has shown to have high specifity to convert the oleuropein into dialdehydes, which have antibacterial activity and are of high interest for their application in the food and pharmaceutical fields. The enzyme is not yet commercially available and advanced clean and safe technologies for its purification able to maintain the functional stability are foreseen. The purification of this protein from fruit extracts has been already tempted by electrophoresis but either enzyme deactivation or high background with unclear profiles occurred. In this work, fruit extracts obtained from the ripening stage that showed the highest enzyme activity have been processed by diafiltration and ultrafiltration. Asymmetric membranes made of polyamide or polysulphone having 50 and 30 kDa molecular weight cut-off, respectively, were tested for the diafiltration process. Ultrafiltration membranes made of polyethersulfone with 4 kDa molecular weight cut-off were used to concentrate the dia-filtered permeate solutions. The efficiency of the separation processes was evaluated byenzyme activity tests using the hydrolysis of p-D-nitrophenyl-${\beta}$-D-glucopyranoside (pNPGlc) as reaction model. Qualitative and quantitative electrophoresis were applied to analyze the composition of protein solution before and after the membrane separation; in addition dot blot and western blot analyses were applied to verify the presence of ${\beta}-glucosidase$ in the processed fractions. The overall results showed that the ${\beta}-glucosidase$ functional stability was preserved during the membrane operations and the removal of 20 kDa proteins allowed to increase the specific activity of the enzyme of about 52% compared to the one present in the initial fruit extract.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.141-146
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• 2000

Glycosidase activities were tested from the grape berries, Vitis labruscana B. Takasumi. Among various glycosidases, $\alpha$-D-galactosidase was found to be the most active in the flesh and other glycosidases were considerably active in the order of the following: $\alpha$-D-mannosidase>$\alpha$-D-glucosidase>$\beta$-D-glucosidase>$\beta$-D-galactosidase. In the seeds, $\alpha$-D-glucosidase activity was the highest and other glycosidases such as $\alpha$-D-galactosidase, $\beta$-D-glucosidase, and $\beta$-D-galactosidase were still significantly active. The $\alpha$-D-galactosidase in the grape flesh was purified over 83-folds through salting-out with $(NH_4)_2SO_4$ and a series of chromatographies employing Sephadex G-50, Octyl-Sepharose, Q-Sepha- rose, and Biogel P-100. The enzyme was a monomer of 45 kDs as determined through SDS-PAGE and Sephacryl S-200 chromatography. The purified enzyme showed a preference of $\alpha$-D-galactose to $\beta$-D-galactose as a substrate about 5.4 times. Sulfhydryl specific reagents such as N-ethylmaleimide and iodoacetamide significantly inhibited the enzyme activity to the extents of 48 and 52% of its initial activity, respectively. The optimumpH range of $\alpha$-D-galactosidase was around 6.5-7.0. The enzyme activity increased by 46% in the presence of 1mM $Fe^{2+}$.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.77-83
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• 1985

The aim of this investigation was to resolve the contradiction between the results of Sternberg and Mandels (1980, 1982)and those of Nisizawa et al., (1971) in cellulase induction by sophorose, and furthermore to study the conditional effects in sophorose-induced cellulase induction in Trichoderma reesei QM 9414. Sophorose could induce the synthesis of CMCase and ${\beta}-glucosidase$ simultaneously. Optimal induction medium by sophorose had the potassium citrate buffer solution of pH 3.0-4.0 for CMCase, but one of pH 5.0-6.0 for ${\beta}-glucosidase$. At this time, two different types of ${\beta}-glucosidase$ could be induced by sophorose: one was extracellular and had maximum at pH 5.0, the other was intracellular and had maximum activity at pH6.5. Induction study showed that $methyl-{\beta}-glucoside$ was not a true inducer of ${\beta}-glucosidase$ and that large ${\beta}-glucosidase$ induction could be obtained only by the addition of sophorose into the induction medium. Glucose repressed the induction of cellulase by sophorose. The repression of glucose could not be overcome by the addition of cyclic AMP into the induction medium.

• Mycobiology
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• v.39 no.2
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• pp.118-120
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• 2011

The ability of Ganoderma to produce extracellular enzymes, including ${\beta}$-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. ${\beta}$-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for ${\beta}$-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neojaponicum showed the strongest activity. Moderate ligninase activity was only observed in Ganoderma neo-japonicum. In contrast, pectinase, amylase, protease, and cellulase were not present in Ganoderma. The results show that the degree of activity of the tested enzymes varied depending on the Ganoderma species tested.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.204-212
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• 2009

A strain producing ${\alpha}$-galactosidase and ${\beta}$-glucosidase was isolated from Kimchi. The isolated strain was identified as Weissella cibaria by 16S rDNA analysis and designated as Weissella cibaria K-M1-4. The enzyme activity of ${\alpha}$-galactosidase and ${\beta}$-glucosidase reached the maximum in the soy medium at $37^{\circ}C$ for 24 hr. The enzymes were purified by ethanol fractionation, DEAE sepharose fast flow, and sephacryl S-100HR column chromatography. ${\alpha}$-Galactosidase specific activity was shown by 576 Units/mg protein and the yield was 3.5% of the total activity of crude extracts. ${\beta}$-glucosidase specific activity was shown by 480 Units/mg protein and the yield was 2.9% of the total activity of crude extracts. The optimum temperature for ${\alpha}$-galactosidase was $60^{\circ}C$ and 43% of its original activity remained when it was treated at $80^{\circ}C$ for 30 min. For ${\alpha}$-galactosidase shows the optimum pH of 8.0 and is fairly stable between pH5.0 and pH9.0. The enzyme activity was increased in the presence of $Fe^{2+}$ and $Cu^{2+}$. The value of Km and Vmax for the enzyme were 0.98 mM and $1.81{\mu}$mole/min, respectively. The ${\beta}$-glucosidase has the optimum temperature of $50^{\circ}C$ and 46% of its original activity remained when it was treated at $80^{\circ}C$ for 30min. Its optimum pH of 7.0 and is fairly stable between pH5.0 and pH9.0. The enzyme activity was increased in the presence of $Fe^{2+},\;Co^{2+}$ and $Cu^{2+}$. The value of Km and Vmax for the enzyme were 1.24 mM and $6.81{\mu}$mole/min, respectively.