• The Korean Journal of Mycology
• /
• v.13 no.4
• /
• pp.203-212
• /
• 1985

Of 450 strains isolated from the soil microbes collected in various locations in Korea, a strain had a strong inhibitory activity against bacterial ${\alpha}-amylase$ and was named strain DMC-72 of the genus Streptomyces. The amylase inhibitory metabolite produced by this strain was purified by means of acetone precipitation, adsorption on Amberlite IRC-50 and SP-Sephadex C-25. The inhibitor was found to be a derivative of oligosaccharides by spectral and chemical data. The inhibitor was stable at the pH range of $1{\sim}13$ and at $100^{\circ}C$ for half an hour, also inhibited other amylases such as salivary ${\alpha}-amylase$, pancreatic ${\alpha}-amylase$, fungal ${\alpha}-amylase$ and glucoamylase. However, it showed no inhibitory activity against ${\alpha}-glucosidase$, ${\beta}-glucosidase$, dextranase, and ${\beta}-amylase$. The kinetic studies of the inhibitor showed that its inhibitory effects on starch hydrolysis by ${\alpha}-amylase$ were noncompetitive.

• Microbiology and Biotechnology Letters
• /
• v.17 no.3
• /
• pp.198-201
• /
• 1989

Steptomyces sp. GI 32 with high production of glucose isomerase was isolated from soil. The maximum enzyme production was observed in the culture medium containing 1% sorbitol, 0.6% tryptone, 0.4% yeast extract, 1mM Fe$_2$(SO$_4$)$_3$ with initial pH 7.0 when the cell was cultured at 35$^{\circ}C$ about 18 hours with shaking. The enzyme was partially purified by ammonium sulfate fractionation and DEAE cellulose chromatography. The enzyme was also appeared to be relatively thermostable, and no apopreciable inactivation was observed after incubation at 7$0^{\circ}C$ for 1 hour. The optimal pH and temperature of the enzyme were pH 8.0 and 7$0^{\circ}C$, respectively.

• Journal of Life Science
• /
• v.9 no.5
• /
• pp.510-517
• /
• 1999

For the treatment of Korean food-wastes, three mesophilic and one thermophilic bacteria were isolated from soil and fermented fertilizers. The thermophilic Streptomyces sp. strain WF021 produced two enzymes which were a protease and a lipase at 55$^{\circ}C$. The mesophilic Bacillus sp. strain WF024 produced four enzymes which were a protease, a lipase, a amylase and a cellulase when the strain was grown both at 3$0^{\circ}C$ and 55$^{\circ}C$. The Bacillus sp. PY123 had produced three enzymes which were a protease, a cellulase and a lipase at 3$0^{\circ}C$. The Bacillus sp. strain CM1 produced three enzymes which were a protease, a amylase, and a cellulase at 3$0^{\circ}C$. The bacteria were grown in media containing 6% NaCl at least and did not have antagonism each other. The four isolates treated much more food-wastes than referance strains did. In a flask without aeration, three reference strains treated 15.4% of food-wastes, while four isolates treated 23.7% of food-wastes. In a flask with aeration, food-wastes were treated 67.3% by four isolates, and 64.3% by three reference strains, but 53.9% without bacteria. However, food-wastes were treated about 78% in a 200$\ell$-reactor made by Siwon Co., while 65.8% in a 20$\ell$-reactor made by Sanyo Co.

• Proceedings of the Microbiological Society of Korea Conference
• /
• 2005.05a
• /
• pp.221.2-221
• /
• 2005

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.627-627
• /
• 2005

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.956-956
• /
• 2005

• 한국당과학회:학술대회논문집
• /
• 2006.11a
• /
• pp.52-52
• /
• 2006

• YAKHAK HOEJI
• /
• v.28 no.2
• /
• pp.89-95
• /
• 1984

Microorganisms having beta-latamase inhibitory activity were selected from soil samples collected from 63 spots throughout the country. Screening procedures consist of two steps. Those are growth inhibition test of penicillinase-producing Staphylococcus aureus by double-layered agar plate containing penicillin G as a substrate, and that of penicillin sensitive Staphylococcus aureus ATCC 6538 in the similiar condition including penicillinase. Finally, a strain was selected from a soil sample of Pa-ju, Kyeong-gi Do. This strain was classified as a Streptomyces sp. by ISP(International Streptomycete Project) and Bergey's manual.

• Proceedings of the Zoological Society Korea Conference
• /
• 1999.10b
• /
• pp.245.1-245
• /
• 1999

No Abstract, See Full Text

• Korean Journal of Microbiology
• /
• v.49 no.4
• /
• pp.369-376
• /
• 2013

We isolated the ${\beta}$-glucosidase producing bacteria (BGB) in ginseng root system (rhizosphere soil, rhizoplane, inside of root). Phylogenetic analysis of the 28 BGB based on the 16S rRNA gene sequences, BGB from rhizosphere soil belong to genus Stenotrophomonas (3 strains), Bacillus (1 strain), and Pseudoxanthomonas (1 strain). BGB isolates from rhizoplane were Stenotrophomonas (16 strains), Streptomyces (1 strain) and Microbacterium (1 strain). BGB from inside of root were categorized into Stenotrophomonas (3 strains) and Lysobacter (2 strains). Especially, Stenotrophomonas comprised the largest portion (approximately 90%) of total isolates and Stenotrophomonas was a dominant group of the ${\beta}$-glucosidase producing bacteria. We selected strain 4KR4, which had high ${\beta}$-glucosidase activity (108.17 unit), could transform ginsenoside Rb1 into Rd, Rg3, and Rh2 ginsenosides. In determining its relationship on the basis of 16S rRNA sequence, 4KR4 strain was most closely related to Stenotrophomonas rhizophila e-$p10^T$ (AJ293463) (99.62%). Therefore, on the basis of these polyphasic taxonomic evidence, the ginsenoside Rb1 converting bacteria 4KR4 was identified as Stenotrophomonas sp. 4KR4 (=KACC 17635).