• Title, Summary, Keyword: ${\alpha}$-glucosidase

Search Result 639, Processing Time 0.054 seconds

Comparative Analysis of $\alpha$-glucosidase Activity in Bombyx mori and Antheraea yamamai

  • Kang, Kyung-Don;Kamita, Shizuo George;Suzuki, Koichi;Seong, Su-Il
    • International Journal of Industrial Entomology
    • /
    • v.21 no.2
    • /
    • pp.163-167
    • /
    • 2010
  • [ $\alpha$ ]Glucosidase (EC 3.2.1.20) is a glycosidase that hydrolyzes disaccharides, oligosaccharides, and polysaccharides resulting in the release of α-D-glucose. In this study, $\alpha$-glucosidase activity in the hemolymph and midgut of the mulberry silkworm Bombyx mori and Japanese oak silkmoth Antheraea yamamai was measured using maltose, sucrose, trehalose, and p-nitrophenyl $\alpha$-D-glucopyranoside as substrates. In general, hemolymph $\alpha$-glucosidase activity was higher in B. mori than in A. yamamai. In contrast, midgut $\alpha$-glucosidase activity was higher in A. yamamai than in B. mori for all of the substrates tested. $\alpha$-Glucosidase activity in the midgut of both B. mori and A. yamamai showed similar responses to changes in pH and temperature for all of the substrates tested. Native (7.5%) PAGE of hemolymph and midgut proteins from B. mori and A. yamamai followed by staining with 4-methylumbelliferyl $\alpha$-D-glucoside (MUG) indicated that the $\alpha$-glucosidases of these related lepidopterans are functionally similar but structurally different. In comparison to $\alpha$-glucosidase activity from A. yamamai, $\alpha$-glucosidase activity from B. mori was generally less sensitive to the $\alpha$-glucosidase inhibitors, 1-deoxynojirimycin (DNJ), acarbose, and voglibose when the activity was determined using maltose, sucrose, and trehalose.

Production of $\alpha$-Glucosidase Inhibitor by $\beta$-Glucosidase Inhibitor-Producing Bacillus lentimorbus B-6

  • Kim, Kyoung-Ja;Yang, Yong-Joon;Kim, Jongkee
    • Journal of Microbiology and Biotechnology
    • /
    • v.12 no.6
    • /
    • pp.895-900
    • /
    • 2002
  • A soil microorganism producing ${\alpha}$- and ${\beta}$-glucosidase inhibitors was identified as Bacillus lentimorbus, based on the fatty acid and morphological analyses, along with biochemical and physiological tests. The ${\alpha}$-glucosidase inhibitor was highly produced by this strain in a culture medium containing $0.25\%$ of sodium glutamate and $0.5\%$ of glucose, pH 8.0 at $30^{\circ}C$ for 2 days. The ${\alpha}$-glucosidase inhibitor from culture filtrate of his strain was identified as water soluble, organic solvent nonextractable, and heat stable. In addition to ${\alpha}$-glucosidase inhibitor, this strain also produced ${\beta}$-glucosidase inhibitor in he same culture medium and this inhibitor showed an antifugal activity against Botrytis cinerea. While the production of ${\alpha}$- glucosidase inhibitor was decreased by a glucose concentration higher than $1\%$, the production of ${\beta}$-glucosidase inhibitor was lot Influenced by a glucose concentration higher than $20\%$. The ${\alpha}$-glucosidase inhibitor from culture filtrate of this strain was separated from the ${\beta}$-glucosidase inhibitor through Sephadex G-100 column chromatography.

Aspergillus niger로 부터 $\alpha$-glucosidase 발현억제 형질전환체의 분리

  • 이동건;이진영;서영배
    • Microbiology and Biotechnology Letters
    • /
    • v.24 no.4
    • /
    • pp.427-429
    • /
    • 1996
  • We have already cloned an extracellular $\alpha$-glucosidase gene from Aspergillus niger with oligonucleotide probe synthesized on the basis of the peptide sequences determined previously. The DNA sequence revealed an open reading frame of 895 amino acids split by three introns. We are attempting to construct an A. niger strain deficient in the $\alpha$-glucosidase enzyme activity, which would be useful for the glucoamylase production without contamination by the industrially undesirable $\alpha$-glucosidase. For destruction of the $\alpha$-glucosidase gene, we try to make transformations. A cloned partial $\alpha$-glucosidase gene was introduced into Aspergillus niger, and transformants with suppressed $\alpha$-glucosidase activity were isolated. The transformants were cultured on YPD medium which contained Hygromycin B at 30$\circ$C. The activity of $\alpha$-glucosidase of the suppressed transformants was compared to that of wild type activity. As shown by southern-hybridization, we detected that the transformant was a heterocaryon.

  • PDF

Inhibitory Effects of Steppogenin and Oxyresveratrol from Morus alba L. against Yeast ${\alpha}$-Glucosidase (뽕나무에서 분리한 Steppogenin과 Oxyresveratrol의 효모 ${\alpha}$-Glucosidase의 억제효과)

  • Chin, Hwi-Seung;NamKung, Woo
    • YAKHAK HOEJI
    • /
    • v.54 no.5
    • /
    • pp.398-402
    • /
    • 2010
  • [ ${\alpha}$ ]Glucosidase inhibitor is a target in the treatment of type II diabetes through the mainly inhibition of glucose levels after meals. In this study, we purified steppogenin and oxyresveratrol from the stem of Morus alba L. and examined their inhibitory activity against yeast ${\alpha}$-glucosidase. Steppogenin and oxyresveratrol were inhibited yeast ${\alpha}$-glucosidase in a dose dependent manner. The $IC_{50}$ activities (50% inhibition) were 34.4 and 9.3 ${\mu}M$, respectively. The kinetic inhibition of steppogenin showed noncompetitive inhibition ($K_m:1.1{\times}10^{-3}M$; $K_i:1{\times}10^{-5}M$), meanwhile oxyresveratrol showed competitive inhibition ($K_m:4.3{\times}10^{-3}M$; $K_i:3.4{\times}10^{-6}M$) against yeast ${\alpha}$-glucosidase. These results indicate that steppogenin and oxyresveratrol are noncompetitive and competitive inhibitors, respectively, against yeast ${\alpha}$-glucosidase.

$\alpha$-Glucosidase Inhibition by Culture Broth of Streptomyces sp. NS15 (Streptomyces sp. NS15 배양액에 의한 $\alpha$-Glucosidase 저해)

  • 백남수;김영만
    • The Korean Journal of Food And Nutrition
    • /
    • v.11 no.6
    • /
    • pp.640-646
    • /
    • 1998
  • For the production of nonprotein $\alpha$-glucosidase inhibitor from the Streptomyces sp. NS15 strain, effects of initial optimum pH, nitrogen sources, carbon sources, cationic metal ions, agitation speed and aeration rate were investigated. Initial optimum pH of medium was 7.0. The most effective nitrogen and carbon sources were soybean meal 2.0%(w/v) and glucose 1.6%(w/v), respectively. The cationic metal ins had no stimulating effect on inhibitory activity of $\alpha$-glucosidase except Fe2+. Agitation speed and aeration rate were effective at 400rpm and 1vvm, respectively. In the jar-fermenter cultivation for 4 days under optimal culture conditions, the culture broth showed the inhibitory acitivity of 3,200units/ml, which is 25 times higher than that of basic medium (CYM) for porcine intestinal $\alpha$-glucosidase. The inhibitory activity of $\alpha$-glucosidase reached about 3,200units/ml after 4 days of cultivation and decreased gradually for a further two days.

  • PDF

Isolation and Characterization of a Thermophilic Bacillus sp. producing a Thermostable $\alpha$-glucosidase (내열성$\alpha$-glucosidase를 생산하는 호열성 Bacillus sp. 균주의 분리 및 특성)

  • 이용억
    • Journal of Life Science
    • /
    • v.8 no.4
    • /
    • pp.387-394
    • /
    • 1998
  • A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

  • PDF

Inhibitory Effect of GE974 isolated from Gyrophora esculenta on ${\alpha}-Glucosidase$ (석이에서 분리한 GE974의 ${\alpha}-Glucosidase$ 저해효과)

  • Choi, Hyuck-Jai;Kim, Dong-Hyun;Kim, Nam-Jae
    • Korean Journal of Pharmacognosy
    • /
    • v.31 no.2
    • /
    • pp.196-202
    • /
    • 2000
  • This study was conducted to search for the ${\alpha}-glucosidase$ inhibitor from the natural products. In the previous study, the water extract of Gyrophora esculenta exhibited a potent inhibitory effect on ${\alpha}-glucosidase$ activities. Then, by bioassay-guided fractionation followed by chromatographic separation of the water extract of Gyrophora esculenta, ${\alpha}-glucosidase$ inhibitor was isolated as GE974. GE974 showed significant inhibitory activities on some kinds of ${\alpha}-glucosidase$ in vitro. Its inhibitory mechanism seemed to be competitive for disaccharides. Also, it markedly inhibited ${\alpha}-glucosidases$ of intestine separated from both nondiabetics and diabetics.

  • PDF

Isolation of $\alpha$-glucosiadase Inhibitor Producing Actinomycetes from Soil Sample (토양시료로부터 $\alpha$-glucosidase 저해제 생성 방선균의 분리)

  • 하남주;최성숙;정남용;김경제
    • Korean Journal of Microbiology
    • /
    • v.38 no.2
    • /
    • pp.139-143
    • /
    • 2002
  • To find $\alpha$-glucosidase inhibitors produced by Actinomycetes, bacteria belonging to Actinomycetes were isolated from soil sample using Bennett's medium. The inhibitory activity induced by these bacteria on $\alpha$-glucosidase, which is the key enzymes far carbohydrates digestion and the prevention of diabetic complications, was investigated. A strain of these bacteria, PM718 potently inhibited $\alpha$-glucosidase activity in vitro.

The Enzymatic Pattern of Bifdobacterium sp. Int-57 Isolated from Korean Feces (한국인 분변으로부터 분리한 Bifidobacterium sp. Int-57의 효소 Pattern)

  • 박헌국;강동현;이계호;윤석환;이세경;지근억
    • Microbiology and Biotechnology Letters
    • /
    • v.20 no.6
    • /
    • pp.647-654
    • /
    • 1992
  • In order to study the physiological properties of the intestinal bacteria, we isolated the intestinal bacteria of Koreans and tested the enzymatic patterns. Isolated Bifidobacterium sp. Int-57 had the higher activity of $\alpha$-glucosidase, $\beta$-glucosidase, $\alpha$-galactosidase, $\beta$-galactosidase. $\beta$-xylosidase and $\alpha$-arabinofuranosidase than other intestinal microorganisms. The effect of the carbon sources on the production of each enzymes of Bijidobacterium sp. Int-57 was investigated. The most suitable carbon source for the production of $\beta$-glucosidase was maltose, for a-glucosidase cellobiose, for $\alpha$-galactosidase raffinose, for $\beta$-galactosidase lactose, and for $\beta$-xylosidase and $\alpha$-arabinofuranosidase xylose, respectively. In addition, we investigated the optimal conditions and pH stability of each crude enzymes. The optimal condition of a-glucosidase was pH 6.0 and $40^{\circ}C$. that of Jj-glucosidase pH 7.0 and 50oe, that of $\beta$-galactosidase pH 7.0 and $50^{\circ}C$, that of $\beta$-xylosidase pH 6.0 and $40^{\circ}C$ , and that of $\alpha$-arabinofuranosidase pH 5.0 and $50^{\circ}C$. respectively. a-Glucosidase was stable at pH 4.0-9.0. Jj-glucosidase at pH 4.0-7.0. $\beta$-galactosidase at pH 4.0-9.0, $\beta$-xylosidase at pH 4.0-6.0, and /3-arabinofuranosidase at pH 7.0-9.0, respectively.

  • PDF

Inhibition Mechanism of $\alpha$-D-Glucosidase Inhibitor from Streptomyces sp (Streptomyces속 균주가 생성하는 $\alpha$-D-Glucosidase 저해물질의 작용상)

  • 도재호;주현규
    • Microbiology and Biotechnology Letters
    • /
    • v.18 no.1
    • /
    • pp.39-43
    • /
    • 1990
  • The inhibitor had the inhibitory activities against hydrolysis of PNPG, sucrose and ONPG by $\alpha$-Dglucosidase, $\alpha$ - and $\beta$ -galactosidase, but it did not inhibit amylases and other carbohydrases. Kinetic studies exhibited that the inhibitory substance non-competitively inhibited the enzyme reaction with a Ki value of 118 $\mu$g/m$\ell$, and enzyme-inhibitor complex was formed slowly.

  • PDF