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1.
Chinese Journal of Biotechnology ; (12): 580-592, 2021.
Article in Chinese | WPRIM | ID: wpr-878583

ABSTRACT

A novel β-glucosidase BglD2 with glucose and ethanol tolerant properties was screened and cloned from the deep-sea bacterium Bacillus sp. D1. The application potential of BglD2 toward polydatin-hydrolyzing was also evaluated. BglD2 exhibited the maximal β-glucosidase activity at 45 °C and pH 6.5. BglD2 maintained approximately 50% of its origin activity after incubation at 30 °C and pH 6.5 for 20 h. BglD2 could hydrolyze a variety of substrates containing β (1→3), β (1→4), and β (1→6) bonds. The activity of β-glucosidase was enhanced to 2.0 fold and 2.3 fold by 100 mmol/L glucose and 150 mmol/L xylose, respectively. BglD2 possessed ethanol-stimulated and -tolerant properties. At 30 °C, the activity of BglD2 enhanced to 1.2 fold in the presence of 10% ethanol and even remained 60% in 25% ethanol. BglD2 could hydrolyze polydatin to produce resveratrol. At 35 °C, BglD2 hydrolyzed 86% polydatin after incubation for 2 h. Thus, BglD2 possessed glucose and ethanol tolerant properties and can be used as the potential candidate of catalyst for the production of resveratrol from polydatin.


Subject(s)
Enzyme Stability , Glucose , Glucosides/pharmacology , Hydrogen-Ion Concentration , Stilbenes/pharmacology , Substrate Specificity , Temperature , Xylose , beta-Glucosidase/genetics
2.
Chinese Journal of Biotechnology ; (12): 244-253, 2019.
Article in Chinese | WPRIM | ID: wpr-771382

ABSTRACT

Natural lignocellulosic materials contain cellulose, hemicellulose, and lignin. Cellulose hydrolysis to glucose requires a series of lignocellulases. Recently, the research on the synergistic effect of lignocellulases has become a new research focus. Here, four lignocellulase genes encoding β-glucosidase, endo-1,4-β-glucanase, xylanase and laccase from termite and their endosymbionts were cloned into pETDuet-1 and pRSFDuet-1 and expressed in Escherichia coli. After SDS-PAGE analysis, the corresponding protein bands consistent with the theoretical values were observed and all the proteins showed enzyme activities. We used phosphoric acid swollen cellulose (PASC) as substrate to measure the synergistic effect of crude extracts of co-expressing enzymes and the mixture of single enzyme. The co-expressed enzymes increased the degradation efficiency of PASC by 44% compared with the single enzyme mixture; while the degradation rate increased by 34% and 20%, respectively when using filter paper and corn cob pretreated with phosphoric acid as substrates. The degradation efficiency of the co-expressed enzymes was higher than the total efficiency of the single enzyme mixture.


Subject(s)
Animals , Cellulase , Cellulose , Hydrolysis , Isoptera , Lignin , Symbiosis , beta-Glucosidase
3.
Electron. j. biotechnol ; 31: 84-92, Jan. 2018. graf, tab, ilus
Article in English | LILACS | ID: biblio-1022139

ABSTRACT

Background: Cellulolytic enzymes of microbial origin have great industrial importance because of their wide application in various industrial sectors. Fungi are considered the most efficient producers of these enzymes. Bioprospecting survey to identify fungal sources of biomass-hydrolyzing enzymes from a high-diversity environment is an important approach to discover interesting strains for bioprocess uses. In this study, we evaluated the production of endoglucanase (CMCase) and ß-glucosidase, enzymes from the lignocellulolytic complex, produced by a native fungus. Penicillium sp. LMI01 was isolated from decaying plant material in the Amazon region, and its performance was compared with that of the standard isolate Trichoderma reesei QM9414 under submerged fermentation conditions. Results: The effectiveness of LMI01 was similar to that of QM9414 in volumetric enzyme activity (U/mL); however, the specific enzyme activity (U/mg) of the former was higher, corresponding to 24.170 U/mg of CMCase and 1.345 U/mg of ß-glucosidase. The enzymes produced by LMI01 had the following physicochemical properties: CMCase activity was optimal at pH 4.2 and the ß-glucosidase activity was optimal at pH 6.0. Both CMCase and ß-glucosidase had an optimum temperature at 60°C and were thermostable between 50 and 60°C. The electrophoretic profile of the proteins secreted by LMI01 indicated that this isolate produced at least two enzymes with CMCase activity, with approximate molecular masses of 50 and 35 kDa, and ß-glucosidases with molecular masses between 70 and 100 kDa. Conclusions: The effectiveness and characteristics of these enzymes indicate that LMI01 can be an alternative for the hydrolysis of lignocellulosic materials and should be tested in commercial formulations.


Subject(s)
Penicillium/enzymology , Cellulase/biosynthesis , beta-Glucosidase/biosynthesis , Oligosaccharides , Temperature , Trichoderma/enzymology , Enzyme Stability , Cellulase/metabolism , beta-Glucosidase/metabolism , Amazonian Ecosystem , Biocatalysis , Fermentation , Hydrogen-Ion Concentration , Hydrolysis , Lignin/metabolism
4.
Article in English | WPRIM | ID: wpr-691402

ABSTRACT

Amarogentin is an efficacious Chinese herbal medicine and a component of the bitter apricot kernel. It is commonly used as an expectorant and supplementary anti-cancer drug. β-Glucosidase is an enzyme that hydrolyzes the glycosidic bond between aryl and saccharide groups to release glucose. Upon their interaction, β-glucosidase catalyzes amarogentin to produce considerable amounts of hydrocyanic acid, which inhibits cytochrome C oxidase, the terminal enzyme in the mitochondrial respiration chain, and suspends adenosine triphosphate synthesis, resulting in cell death. Hydrocyanic acid is a cell-cycle-stage-nonspecific agent that kills cancer cells. Thus, β-glucosidase can be coupled with a tumor-specific monoclonal antibody. β-Glucosidase can combine with cancer-cell-surface antigens and specifically convert amarogentin to an active drug that acts on cancer cells and the surrounding antibodies to achieve a killing effect. β-Glucosidase is injected intravenously and recognizes cancer-cell-surface antigens with the help of an antibody. The prodrug amarogentin is infused after β-glucosidase has reached the target position. Coupling of cell membrane peptides with β-glucosidase allows the enzyme to penetrate capillary endothelial cells and clear extracellular deep solid tumors to kill the cells therein. The Chinese medicine amarogentin and β-glucosidase will become an important treatment for various tumors when an appropriate monoclonal antibody is developed.


Subject(s)
Amygdalin , Therapeutic Uses , Antibodies, Monoclonal , Therapeutic Uses , Antineoplastic Agents , Therapeutic Uses , Cell-Penetrating Peptides , Therapeutic Uses , Humans , Iridoids , Therapeutic Uses , Prodrugs , Therapeutic Uses , beta-Glucosidase , Therapeutic Uses
5.
Electron. j. biotechnol ; 30: 83-87, nov. 2017. graf, tab
Article in English | LILACS | ID: biblio-1021898

ABSTRACT

Background: ß-Glucosidase assay is performed with purified or semipurified enzymes extracted from cell lysis. However, in screening studies, to find bacteria with ß-glucosidase activity among many tested bacteria, a fast method without cell lysis is desirable. In that objective, we report an in vivo ß-glucosidase assay as a fast method to find a ß-glucosidase producer strain. Results: The method consists in growing the strains for testing in a medium supplemented with the artificial substrate p-nitrophenyl-ß-glucopyranoside (pNPG). The presence of ß-glucosidases converts the substrate to p-nitrophenol (pNP), a molecule that can be easily measured in the supernatant spectrophotometrically at 405 nm. The assay was evaluated using two Bifidobacterium strains: Bifidobacterium longum B7254 strain that lacks ß-glucosidase activity and Bifidobacterium pseudocatenulatum B7003 strain that shows ß-glucosidase activity. The addition of sodium carbonate during pNP measurement increases the sensitivity of pNP detection and avoids the masking of absorbance by the culture medium. Furthermore, we show that pNP is a stable enzymatic product, not metabolized by bacteria, but with an inhibitory effect on cell growth. The ß-glucosidase activity was measured as units of enzyme per gram per minute per dry cell weight. This method also allowed the identification of Lactobacillus strains with higher ß-glucosidase activity among several lactobacillus species. Conclusion: This in vivo ß-glucosidase assay can be used as an enzymatic test on living cells without cell disruption. The method is simple, quantitative, and recommended, especially in studies screening for bacteria not only with ß-glucosidase activity but also with high ß-glucosidase activity.


Subject(s)
Bifidobacterium/isolation & purification , Bifidobacterium/enzymology , beta-Glucosidase/metabolism , Bifidobacterium/metabolism , Nitrophenylgalactosides , Enzyme Assays , Bifidobacterium longum/isolation & purification , Bifidobacterium longum/enzymology , Bifidobacterium pseudocatenulatum/isolation & purification , Bifidobacterium pseudocatenulatum/enzymology , Lactobacillus/isolation & purification , Lactobacillus/enzymology , Lactobacillus/metabolism , Nitrophenols
6.
Electron. j. biotechnol ; 26: 20-26, Mar. 2017. ilus, graf, tab
Article in English | LILACS | ID: biblio-1009753

ABSTRACT

Background: Ginsenoside is the most important secondary metabolite in ginseng. Natural sources of wild ginseng have been overexploited. Although root culture can reduce the length of the growth cycle of ginseng, the number of species of ginsenosides is reduced and their contents are lower in the adventitious roots of ginseng than in the roots of ginseng cultivated in the field. Results: In this study, 147 strains of ß-glucosidase-producing microorganisms were isolated from soil. Of these, strain K35 showed excellent activity for converting major ginsenosides into rare ginsenosides, and a NCBI BLAST of its 16S rDNA gene sequence showed that it was most closely related to Penicillium sp. (HQ608083.1). Strain K35 was used to ferment the adventitious root extract, and the fermentation products were analyzed by high-performance liquid chromatography. The results showed that the content of the rare ginsenoside CK was 0.253 mg mL-1 under the optimal converting conditions of 9 d of fermentation at pH 7.0 in LL medium, which was significantly higher than that in the adventitious roots of ginseng. Conclusion: These findings may not only solve the problem of low productivity of metabolite in ginseng root culture but may also result in the development of a new valuable method of manufacturing ginsenoside CK.


Subject(s)
beta-Glucosidase/metabolism , Plant Roots/metabolism , Ginsenosides/metabolism , Panax/metabolism , Penicillium , Biotransformation , Chromatography, High Pressure Liquid , Plant Roots/chemistry , Bioreactors , Ginsenosides/isolation & purification , Fermentation , Panax/growth & development , Panax/chemistry
7.
Mycobiology ; : 119-122, 2017.
Article in English | WPRIM | ID: wpr-729304

ABSTRACT

Herein, nuruks derived from non-glutinous and glutinous rice inoculated with Aspergillus oryzae N159-1 (having high alpha-amylase and beta-glucosidase activities) were used to produce Korean alcoholic beverages. The resultant beverages had enhanced fruity (ethyl caproate and isoamyl alcohol) and rose (2-phenethyl acetate and phenethyl alcohol) flavors and high taste scores.


Subject(s)
Alcoholic Beverages , Alcoholics , alpha-Amylases , Aspergillus oryzae , Aspergillus , beta-Glucosidase , Beverages , Humans
8.
Braz. j. microbiol ; 46(3): 903-910, July-Sept. 2015. tab, ilus
Article in English | LILACS | ID: lil-755814

ABSTRACT

Nineteen fungi and seven yeast strains were isolated from sugarcane bagasse piles from an alcohol plant located at Brazilian Cerrado and identified up to species level on the basis of the gene sequencing of 5.8S-ITS and 26S ribosomal DNA regions. Four species were identified: Kluyveromyces marxianus, Aspergillus niger, Aspergillus sydowii and Aspergillus fumigatus, and the isolates were screened for the production of key enzymes in the saccharification of lignocellulosic material. Among them, three strains were selected as good producers of hemicellulolitic enzymes: A. niger (SBCM3), A. sydowii (SBCM7) and A. fumigatus (SBC4). The best β-xylosidase producer was A. niger SBCM3 strain. This crude enzyme presented optimal activity at pH 3.5 and 55 °C (141 U/g). For β-glucosidase and xylanase the best producer was A. fumigatus SBC4 strain, whose enzymes presented maximum activity at 60 °C and pH 3.5 (54 U/g) and 4.0 (573 U/g), respectively. All these crude enzymes presented stability around pH 3.0–8.0 and up to 60 °C, which can be very useful in industrial processes that work at high temperatures and low pHs. These enzymes also exhibited moderate tolerance to ethanol and the sugars glucose and xylose. These similar characteristics among these fungal crude enzymes suggest that they can be used synergistically in cocktails in future studies of biomass conversion with potential application in several biotechnological sectors.

.


Subject(s)
Aspergillus fumigatus/enzymology , Aspergillus niger/enzymology , Cellulose/metabolism , /metabolism , Kluyveromyces/enzymology , Saccharum/microbiology , Xylosidases/metabolism , beta-Glucosidase/metabolism , Aspergillus fumigatus/isolation & purification , Aspergillus fumigatus/metabolism , Aspergillus niger/isolation & purification , Aspergillus niger/metabolism , Base Sequence , Biomass , Brazil , DNA, Fungal/genetics , DNA, Intergenic/genetics , Fermentation , Kluyveromyces/isolation & purification , Kluyveromyces/metabolism , Lignin/metabolism , Molecular Typing , Mycological Typing Techniques , RNA, Ribosomal/genetics , Sequence Analysis, DNA
9.
Braz. j. microbiol ; 46(1): 23-28, 05/2015. graf
Article in English | LILACS | ID: lil-748234

ABSTRACT

Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation). The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein). Compared to the native enzyme, the conjugated form exhibited: a higher optimal reaction temperature, a lower Ea (activation energy), a higher Km (Michaelis constant) and Vmax (maximal reaction rate), and improved thermal stability. The calculated t1/2 (half-life) values of heat in-activation at 60 °C and 70 °C were 245.7 and 54.5 min respectively, whereas at these temperatures the native enzyme was less stable (t1/2 of 200.0 and 49.5 min respectively). The conjugated enzyme retained 32.3 and 29.7%, respectively from its initial activity in presence of 5 mM Sodium Dodecyl Sulphate (SDS) and p-Chloro Mercuri Benzoate (p-CMB), while the native enzyme showed a remarkable loss of activity (retained activity 1.61 and 13.7%, respectively). The present work has established the potential of glycosylation to enhance the catalytic properties of β-glucosidase enzyme, making this enzyme potentially feasible for biotechnological applications.


Subject(s)
Aspergillus niger/enzymology , beta-Glucosidase/chemistry , beta-Glucosidase/metabolism , Enzyme Stability , Enzyme Inhibitors/metabolism , Glycosylation , Kinetics , Temperature
10.
Article in Chinese | WPRIM | ID: wpr-250444

ABSTRACT

The reaction conditions of baicalin hydrolyzed into baicalein by a kind of thermophilic and sugar-tolerant beta-glucosidase were studied in this paper. The beta-glucosidase could catalyze baicalin into baicalein well in the acetic acid-sodium acetate buffer. The optimal enzyme activity was at 85 degrees C and pH 5.5. The enzyme was stable at the temperature less than 85 degrees C and pH range of 5-7.5. The maximum reaction rate V. and michaelis constant K. were 0.41 mmol x L(-1) x min(-1) and 3.31 mmol x L(-1) respectively. Different metal ions had different effects on the activity of enzyme. Na+ existing in acetic acid-sodium acetate buffer had an activation effect on enzyme. The enzyme activity was enhanced by the concentrations of glucose below 0.6 mol x L(-1), and was gradually inhibited when monosaccharide concentration was over 0.6 mol x L(-1). When the monosaccharide concentration reached 1.2 mol x L(-1), the inhibition rate of enzyme activity was about 50%, which showed good glucose tolerance. The good reaction conditions through the experiment have been determined as follows, the substrate: enzyme dose was 1 g: 0.2 mL, acetic acid-sodium acetate buffer pH 5.5, reaction temperature 85 degrees C, reaction time 10 h, and the enzymatic hydrolyzation ratio could reach 97%.


Subject(s)
Biocatalysis , Enzyme Stability , Flavanones , Chemistry , Flavonoids , Chemistry , Glucose , Chemistry , Hot Temperature , Hydrolysis , Kinetics , beta-Glucosidase , Chemistry
11.
Mycobiology ; : 57-62, 2015.
Article in English | WPRIM | ID: wpr-729860

ABSTRACT

beta-Glucosidase, which hydrolyzes cellobiose into two glucoses, plays an important role in the process of saccharification of the lignocellulosic biomass. In this study, we optimized the activity of beta-glucosidase of brown-rot fungus Fomitopsis pinicola KCTC 6208 using the response surface methodology (RSM) with various concentrations of glucose, yeast extract and ascorbic acid, which are the most significant nutrients for activity of beta-glucosidase. The highest activity of beta-glucosidase was achieved 3.02% of glucose, 4.35% of yeast extract, and 7.41% ascorbic acid where ascorbic acid was most effective. The maximum activity of beta-glucosidase predicted by the RSM was 15.34 U/mg, which was similar to the experimental value 14.90 U/mg at the 16th day of incubation. This optimized activity of beta-glucosidase was 23.6 times higher than the preliminary activity value, 0.63 U/mg, and was also much higher than previous values reported in other fungi strains. Therefore, a simplified medium supplemented with a cheap vitamin source, such as ascorbic acid, could be a cost effective mean of increasing beta-glucosidase activity.


Subject(s)
Ascorbic Acid , beta-Glucosidase , Biomass , Cellobiose , Coriolaceae , Fungi , Glucose , Vitamins , Yeasts
12.
Acta Pharmaceutica Sinica ; (12): 1652-1659, 2015.
Article in Chinese | WPRIM | ID: wpr-320028

ABSTRACT

This study was performed to prepare immobilized β-glucosidase and snailase, then optimize and compare the process conditions for conversion of icariin. Immobilized β-glucosidase and snailase were prepared using crosslink-embedding method. The best conditions of the preparation process were optimized by single factor analysis and the properties of immobilized β-glucosidase and snailase were investigated. The reaction conditions including temperature, pH, substrate ratio, substrate concentration, reaction time and reusing times of the conversion of icariin using immobilized β-glucosidase or snailase were optimized. Immobilized β-glucosidase and snailase exhibited better heat stabilities and could remain about 60% activity after storage at 4 degrees C for 4 weeks. The optimized conditions for the conversion of icariin were as follows, the temperature of 50 degrees C, pH of 5.0, enzyme and substrate ratio of 1 : 1, substrate concentration of 0.1 mg x mL(-1), reaction time of 6 h for β-glucosidase and 2 h for snailase, respectively. In 5 experiments, the average conversion ratio of immobilized β-glucosidase and snailase was 70.76% and 74.97%. The results suggest an effect of promoted stabilities, prolonged lifetimes in both β-glucosidase and snailase after immobilization. The immobilized β-glucosidase and snailase exhibited a higher conversion rate and reusability compared to the free β-glucosidase and snailase. Moreover, the conversion rate of immobilized snailase was higher than that of immobilized β-glucosidase. The process of icariin conversion using immobilized β-glucosidase and snailase was moderate and feasible, which suggests that immobilized enzymes may hold a promise for industrial usage.


Subject(s)
Enzymes, Immobilized , Chemistry , Flavonoids , Chemistry , Hydrolysis , Temperature , beta-Glucosidase , Chemistry
13.
Braz. j. microbiol ; 45(4): 1139-1144, Oct.-Dec. 2014. ilus
Article in English | LILACS | ID: lil-741263

ABSTRACT

Bacteria have evolved various mechanisms to extract utilizable substrates from available resources and consequently acquire fitness advantage over competitors. One of the strategies is the exploitation of cryptic cellular functions encoded by genetic systems that are silent under laboratory conditions, such as the bgl (β-glucoside) operon of E. coli. The bgl operon of Escherichia coli, involved in the uptake and utilization of aromatic β-glucosides salicin and arbutin, is maintained in a silent state in the wild type organism by the presence of structural elements in the regulatory region. This operon can be activated by mutations that disrupt these negative elements. The fact that the silent bgl operon is retained without accumulating deleterious mutations seems paradoxical from an evolutionary view point. Although this operon appears to be silent, specific physiological conditions might be able to regulate its expression and/or the operon might be carrying out function(s) apart from the utilization of aromatic β-glucosides. This is consistent with the observations that the activated operon confers a Growth Advantage in Stationary Phase (GASP) phenotype to Bgl+ cells and exerts its regulation on at least twelve downstream target genes.


Subject(s)
Escherichia coli/enzymology , Escherichia coli/genetics , Gene Expression Regulation , beta-Glucosidase/genetics , beta-Glucosidase/metabolism , Arbutin/metabolism , Benzyl Alcohols/metabolism , Escherichia coli/growth & development , Escherichia coli/metabolism , Glucosides/metabolism , Operon
14.
Rev. bras. hematol. hemoter ; 36(5): 345-350, Sep-Oct/2014. tab, graf
Article in English | LILACS | ID: lil-725681

ABSTRACT

Objective: To evaluate the impact of enzyme replacement therapy for Gaucher Disease on clinical and laboratory parameters after two, five and ten years of treatment. Methods: Data were collected from patient records and analyzed using BioEstat software (version 5.0). Student's t-test, Analysis of Variance (ANOVA), Wilcoxon test and Kruskal–Wallis test were used for statistical analysis. Hepatomegaly and splenomegaly were analyzed using the Kappa test. Results: There was a significant increase in hemoglobin levels (p-value <0.01) and platelet counts (p-value = 0.01) within two years of therapy. At the same time, the frequencies of splenomegaly (p-value <0.01) and hepatomegaly (p-value <0.05) reduced. These results were similar at five and ten years of enzyme replacement therapy. Conclusions: There are substantial and quick (within two years) laboratory and clinical responses to enzyme replacement therapy. These improvements continue as long as enzyme replacement therapy is administered every two weeks, as recommended by the literature...


Subject(s)
Humans , Anemia , Gaucher Disease/diagnosis , Gaucher Disease/therapy , Enzyme Replacement Therapy , Splenomegaly , beta-Glucosidase , Mononuclear Phagocyte System
15.
Mycobiology ; : 256-261, 2014.
Article in English | WPRIM | ID: wpr-729879

ABSTRACT

A beta-glucosidase producing yeast strain was isolated from Korean traditional rice wine. Based on the sequence of the YCL008c gene and analysis of the fatty acid composition, the isolate was identified as Saccharomyces cerevisiae strain HJ-014. S. cerevisiae HJ-014 produced ginsenoside Rd, F2, and compound K from the ethanol extract of red ginseng. The production was increased by shaking culture, where the bioconversion efficiency was increased 2-fold compared to standing culture. The production of ginsenoside F2 and compound K was time-dependent and thought to proceed by the transformation pathway of: red ginseng extract-->Rd-->F2-->compound K. The optimum incubation time and concentration of red ginseng extract for the production of compound K was 96 hr and 4.5% (w/v), respectively.


Subject(s)
beta-Glucosidase , Ethanol , Panax , Saccharomyces cerevisiae , Wine , Yeasts
16.
Mycobiology ; : 368-375, 2014.
Article in English | WPRIM | ID: wpr-729766

ABSTRACT

Red ginseng (Panax ginseng), a Korean traditional medicinal plant, contains a variety of ginsenosides as major functional components. It is necessary to remove sugar moieties from the major ginsenosides, which have a lower absorption rate into the intestine, to obtain the aglycone form. To screen for microorganisms showing bioconversion activity for ginsenosides from red ginseng, 50 yeast strains were isolated from Korean traditional meju (a starter culture made with soybean and wheat flour for the fermentation of soybean paste). Twenty strains in which a black zone formed around the colony on esculin-yeast malt agar plates were screened first, and among them 5 strains having high beta-glucosidase activity on p-nitrophenyl-beta-D-glucopyranoside as a substrate were then selected. Strain JNO301 was finally chosen as a bioconverting strain in this study on the basis of its high bioconversion activity for red ginseng extract as determined by thin-layer chromatography (TLC) analysis. The selected bioconversion strain was identified as Candida allociferrii JNO301 based on the nucleotide sequence analysis of the 18S rRNA gene. The optimum temperature and pH for the cell growth were 20~30degrees C and pH 5~8, respectively. TLC analysis confirmed that C. allociferrii JNO301 converted ginsenoside Rb1 into Rd and then into F2, Rb2 into compound O, Rc into compound Mc1, and Rf into Rh1. Quantitative analysis using high-performance liquid chromatography showed that bioconversion of red ginseng extract resulted in an increase of 2.73, 3.32, 33.87, 16, and 5.48 fold in the concentration of Rd, F2, compound O, compound Mc1, and Rh1, respectively.


Subject(s)
Absorption , Agar , Base Sequence , beta-Glucosidase , Candida , Chromatography, Liquid , Chromatography, Thin Layer , Fermentation , Flour , Genes, rRNA , Ginsenosides , Hydrogen-Ion Concentration , Intestines , Panax , Plants, Medicinal , Soybeans , Triticum , Yeasts
17.
Article in Chinese | WPRIM | ID: wpr-300171

ABSTRACT

The optimum conditions of baicalin hydrolysis into baicalein by immobilized beta-glucosidase in a two-phase system was studied and the yield was observed. A two-phase system comprising of sodium acetate buffer and chloroform was determined by comparing the solubleness of baicalein in different solvents and partition coefficient of baicalein in related aqueous-organic two-phase system. beta-Glucosidase was immobilized by the crosslinking-embedding method using sodium alginate as the carrier The optimum reaction temperature, pH value, Michaelis constant, the thermal stability and pH stability were assayed. By comparing the yield of baicalin hydrolysis into baicalein by immobilized beta-glucosidase in two-phase system, the optimum reaction conditions were determined-the optimum reaction temperature, pH value and time were 50 degrees C, 5.0 and 10 h, respectively. The yield of baicalein was 85.28%. Compare with one-phase system, two-phase system had an advantage in reaction rate and yield.


Subject(s)
Biocatalysis , Drugs, Chinese Herbal , Chemistry , Enzyme Stability , Enzymes, Immobilized , Chemistry , Flavanones , Chemistry , Flavonoids , Chemistry , Hydrolysis , beta-Glucosidase , Chemistry
18.
Chinese Journal of Biotechnology ; (12): 1245-1253, 2013.
Article in Chinese | WPRIM | ID: wpr-242485

ABSTRACT

Exploring new beta-glucosidase genes is of great importance to industrialize beta-glucosidase. The genomes of Aspergillus fumigatus contain a bgl gene, which encodes a 65 kDa putative beta-glucosidase. The bgl gene was cloned into an expression plasmid and transformed to Escherichia coli BL21 (DE3). The bgl was expressed upon induction of Isopropyl beta-D-1-thiogalactopyranoside (IPTG). The recombinant protein was purified by GST-tag affinity chromatography. The purified recombinant Bgl was characterized using Esculin as substrate. The optimum temperature and pH were 45 degrees C and 5.0-6.0, respectively. The K(m) for Esculin was 17.7 mmol/L. The enzyme was stable in the range of pH 4-7. After incubation at 70 degrees C for 2 h, the recombinant Bgl remained 60% of its activity. Metal ions and chemical reagents had different influences on the activity of beta-glucosidase. Ca2+ (1 mmol/L) could increase enzyme activity slightly. On the contrary, the enzyme activity was greatly inhibited by 5 mmol/L Sodium dodecyl sulfate (SDS). Based on our results, the A. fumigatus Bgl was thermostable beta-glucosidase.


Subject(s)
Aspergillus fumigatus , Cloning, Molecular , Enzyme Stability , Escherichia coli , Genetics , Metabolism , Recombinant Proteins , Genetics , Metabolism , beta-Glucosidase , Genetics , Metabolism
19.
Chinese Journal of Biotechnology ; (12): 1254-1267, 2013.
Article in Chinese | WPRIM | ID: wpr-242484

ABSTRACT

Constructing ethanologenic strains with cellulose activity is important to achieve consolidated bioprocessing of lignocellulose for ethanol production. In this study, we integrated the pyruvate decarboxylase gene pdc and alcohol dehydrogenase gene adhB from Zymomonas mobilis ZM4 into Escherichia coli JM109 by Red recombination method to generatea recombinant strain E. coli P81 that could produce ethanol from glucose. Abeta-glucosidase gene bglB from Bacillus polymyxa 1.794 was cloned into the recombinant E. coli P81 and beta-glucosidase was expressed to give a new recombinant strain E. coli P81 (pUC19-bglB) with dual functions of cellobiose degradation and ethanol production. The extracellular beta-glucosidaseactivity was 84.78 mU/mL broth and the extracellular cellobiase activity of E. coli P81 (pUC19-bglB) was 32.32 mU/mL broth. E. coli P81 (pUC19-bglB) fermented cellobiose to ethanol with a yield of 55.8% of the theoretical value, and when glucose and cellobiose were co-fermented, the ethanol yield reached 46.5% of thetheoretical value. The construction of consolidated bioprocessing strain opens the possibility to convert cellobiose to ethanol in a single bioprocess.


Subject(s)
Bacterial Secretion Systems , Cellulose , Metabolism , Escherichia coli , Genetics , Metabolism , Ethanol , Metabolism , Fermentation , Recombinant Proteins , Genetics , beta-Glucosidase , Genetics
20.
Braz. j. microbiol ; 44(2): 569-576, 2013. graf, tab
Article in English | LILACS | ID: lil-688590

ABSTRACT

The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L), which was not detected in the T. reesei culture.


Subject(s)
Aspergillus/enzymology , Carboxylic Ester Hydrolases/metabolism , Xylosidases/metabolism , beta-Glucosidase/metabolism , Aspergillus/genetics , Aspergillus/growth & development , Carbon/metabolism , Culture Media/chemistry , Nitrogen/metabolism , Temperature
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