• Journal of Life Science
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• v.8 no.3
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• pp.326-332
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• 1998

Cyclodextrin glucanotransferase from B. stearothermophilus KJ16 that can produce both cyclodextrin glucanotransferase and cyclodextrinase was purified by ammonium sulfate precipitation, DEAE-cellulose chromatography, Sephadex G-100 chromatography, and FPLC. The molecular weight of the purifice enzyme was about 65,000 dalton by SDS-PAGE. The optimal pH and temperature were 6.0 and $60^{\circ}C$, respectively. The enzyme was stable at $50^{\circ}C$ for 1 hr and in the pH range of 5.5 and 8.5. Mercaptoethanol and dithiothreitol inhibited the enzyme activity strongly. The enzyme produced 60% cyclodextrin(CD) from 5% soluble starch with the $^{\alpha}$, $^{\beta}$, $^{\gamma}$-CD ratio of 42:46:12. Amylopectin was the most suitable substrate with 67% conversion to CD.

• Journal of Life Science
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• v.16 no.1
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• pp.22-29
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• 2006

Effect of microbial products made of Bacillus stearothermophilus DL-3 on growth of chickens and pigs was investigated. Two types of microbial product were made in this study. One is the microbial product made of culture broth of B. stearothemophilus DL-3 and rice bran which named as the microbial product A. The other is the microbial product made of culture broth of B. stearothermophilus DL-3, apple pomace, soybean pomace and rice bran which named as the microbial product B. Chickens were divided into three groups and each group was fed with $100\%$ general feed, $90\%$ general feed supplemented with $10\%$ microbial product A or $90\%$ general feed supplemented with $10\%$ microbial product B. The average chicken weight of each group was $41.1{\pm}2.5g,\;41.6{\pm}3.2g\;and\;42.3{\pm}2.9g$ and those after 28 days was $547.7{\pm}91.7g,\;560.1{\pm}17.2g\;and\;562.2{\pm}32.5g$, respectively. The average weight gain for each group was 506.6 g, 518.6 g and 519.9 g, respectively, and weight increases of groups fed with $90\%$ general feeder and $10\%$ microbial product A and B were $2.4\%\;and\;2.6\%$ higher than the group fed with $100\%$ general feed. Pigs were also divided into three groups and each group was fed like chickens. The average weight of each group was $9.3{\pm}1.0kg,\;9.4{\pm}1.1kg\;and\;9.6{\pm}1.0kg$ and those after 37 days was $19.3{\pm}4.1kg,\;20.2{\pm}3.9kg\;and\;20.8{\pm}4.2kg$, respectively. The average Weight gain for each group was 10.65 kg, 10.82 kg and 11.20 kg, respectively, and weight increases of groups fed with $90\%$ general feeder and $10\%$ microbial product A and B were $1.6\%$ and $5.2\%$ higher than the group fed with $100\%$ general feed.