• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1115-1120
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• 2008

A novel cathepsin B inhibitor-producing bacterium was isolated from marine sediments and identified based on its 16S rDNA sequence as Pseudomonas sp. strain PB01 (Accession No. EU126129). The growth and enzyme inhibitor production were investigated under various culture conditions. A mixture of organic nitrogen source was required for the optimal production, whereas both glucose and maltose proved to be the effective carbon sources for cathepsin B inhibitor production. Other optimal culture conditions included temperature range between 25 and $28^{\circ}C$, initial medium pH of 6.6, and shaking speed of 200 rpm. Under these optimal conditions, the maximum inhibitory activity from culture broth was approximately 50% after 30 h of cultivation. Additionally, kinetic study revealed that inhibitor production paralleled with cell growth, which suggested that the inhibitor may be a primary metabolite of that bacterium.

• Research in Plant Disease
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• v.12 no.2
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• pp.85-90
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• 2006

Bacillus subtilis BD0310 isolated from tea leaves was used for the development of a biofungicide against Pestalotiopsis longiseta causing gray blight of tea plants. The optimum growth conditions were investigated for the mass cultivation of the microbial agent. The optimum temperature and cultivation time were determined as $12{\sim}24$ hours at $30^{\circ}C$ and the optimum initial pH was pH 7.0 in nutrient broth. Among the tested carbon sources of fructose, galactose, glucose, glycerol, inositol, lactose, maltose, sorbitol and starch, maltose and inositol were found to highly increase antifungal activity of the microbial agent against P. longiseta. Yeast extract and tryptone apparently increased antifungal activity of the microbial agent among the tested nitrogen sources of casein, tryptone, malt extract, yeast extract and $(NH_4)_2SO_4$. The results will make a contribution to mass production of the antagonistic bacterium Bacillus subtilis BD0310 for development of a microbial agent controlling gray blight of tea plants.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.94-99
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• 1999

For the purpose of utilizing cellulose resources by cellulolytic enzymes of Stropharia rugosoannulata, it's cultural conditions for the prodution of cellulolytic enzymes in synthetic media were investigated. The optimum pH for the production of Avicelase and ${\beta}-glucosidase$ was pH 5.0, while that of CMCase was pH 4.0. The optimum temperature for the production of Avicelase, CMCase and ${\beta}-glucosidase$ was $40^{\circ}C$. Among the carbon sources, xylose was good for the production of CMCase and ${\beta}-glucosidase$, but maltose was good for the production of Avicelase. The optimum concentration of the carbon sources for the production of CMCase, Avicelase and ${\beta}-glucosidase$ was 1.0, 0.8 and 1.1%, respectively. As inorganic nitrogen sources, $NH_4Cl$ was good for the production of all the three cellulolytic enzymes. The optimum concentration of $NH_4Cl$ for the production of CMCase was 0.3% while that of Avicelase and ${\beta}-glucosidase$ was 0.4%. As organic nitrogen sources, malt extract was good for the production of all the three cellulolytic enzymes. The optimum concentration of organic nitrogen for the production of ${\beta}-glucosidase$ was 1.3% while that of CMCase and Avicelase was 1.0%. As the mineral sources, $CoCl_2$ good for the was good for the production of all the three cellulolytic enzymes. The optimum concentration of $CoCl_2$ for the production of all the three enzymes was 0.35%.

• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.546-551
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• 1997

A bacterium producing the extracellular cellulases was isolated from soil and has been identified as Bacillus sp. The isolate, named Bacillus sp. 79-23, was shown to be very similar to B. subtilis on the basis of its biochemical properties. The carboxymethyl cellulase (CMCase) of culture supernatant was most active at 60$\circ$C and pH 6.0, and retained 90% of its maximum activity at pH 7.0. The additional carbon sources affected the CMCase productivity than nitrogen sources in the culture medium. The carbon sources including wheat bran, rice straw, maltose and glucose increased the enzyme productivty. Especially, the maximum CMCase production was 5.2 units/ml in LB medium supplemented with 3% (w/v) wheat bran, which was 13-folds more than that in LB medium. It was found that the enzyme production was in association with the growth of Bacillius sp. 79-23. But, whean bran did not affect the growth of isolate, suggesting that increasement of CMCase production was owing to the induction of CMCase biosynthesis by wheat bran. In addition, both water-soluble and insoluble components of wheat bran was involved in induction of CMCase biosynthesis.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.58-68
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• 2012

An investigation was conducted on the enhancement of production and purification of an oxidant and SDS-stable alkaline protease (BHAP) secreted by an alkalophilic Bacillus horikoshii, which was screened from the body fluid of a unique Korean polychaeta (Periserrula leucophryna) living in the tidal mud flats of Kwangwha Island in the Korean West Sea. A prominent effect on BHAP production was obtained by adding 2% maltose, 1% sodium citrate, 0.8% NaCl, and 0.6% sodium carbonate to the culturing medium. The optimal medium for BHAP production contained (g/l) SBM, 15; casein, 10; $K_2HPO_4$, 2; $KH_2PO_4$, 2; maltose, 20; sodium citrate, 10; $MgSO_4$, 0.06; NaCl, 8; and $Na_2CO_3$, 6. A protease yield of approximately 56,000 U/ml was achieved using the optimized medium, which is an increase of approximately 5.5-fold compared with the previous optimization (10,050 U/ml). The BHAP was homogenously purified 34-fold with an overall recovery of 34% and a specific activity of 223,090 U/mg protein using adsorption with Diaion HPA75, hydrophobic interaction chromatography (HIC) on Phenyl-Sepharose, and ion-exchange chromatography on a DEAE- and CM-Sepharose column. The purified BHAP was determined a homogeneous by SDS-PAGE, with an apparent molecular mass of 28 kDa, and it showed extreme stability towards organic solvents, SDS, and oxidizing agents. The $K_m$ and $k_{cat}$ values were 78.7 ${\mu}M$ and $217.4s^{-1}$ for N-succinyl-Ala-Ala-Pro-Phe-pNA at $37^{\circ}C$ and pH 9, respectively. The inhibition profile exhibited by PMSF suggested that the protease from B. horikoshii belongs to the family of serine proteases. The BHAP, which showed high stability against SDS and $H_2O_2$, has significance for industrial application, such as additives in detergent and feed industries.

• Applied Biological Chemistry
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• v.39 no.3
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• pp.177-182
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• 1996

Effects of 14 carbohydrates supplied as carbon sources on cell growth and sporulation of, and the production of insecticidal crystal proteins by Bacillus thuringiensis strains were investigated in liquid cultures. Strains grew well in media containing any one of the 14 carbohydrates supplied, reaching maximum cell densities of $10^7{\sim}10^8\;cells/ml$ in 16.7 to 22 hours after inoculation depending on the strain. Spores first appeared in 16.7 to 24.7 hours after inoculation, and 80% sporulation was reached in 28 to 51.3 hours after inoculation depending on the strain. No change in pH of media was observed after cell multiplication. The production of total protein was highest when supplied with sucrose and was lowest with starch. More insecticidal crystal proteins were produced when supplied with glucose, lactose, maltose, or sucrose. The amount of insecticidal crystal proteins produced by the strains was proportional to that of the total protein. The relative amount of individual insecticidal crystal protein species produced by B.t. kurstaki and B.t. israelensis was not influenced by the carbohydrates supplied.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.33-41
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• 1976

These experiment were conducted to investigate the cultural condition of the lipase production by Rhizopus japonicus. The results obtained were as follows: 1. Soybean meal and ammonium sulfate were the most effective in the lipase production as organic and inorganic nitrogen sources, respectively. 2. The lipase production was strongly inhibited, when added as carbon sources xylose, glucose, fructose, galactose, maltose, soluble starch, and dextrin causing the lowering of pH of the medium during culture. Sucrose did not inhibit the lipase production, but not caused any effect when added. 3. $K_2HPO_4$ as phosphate salt and $MgSO_4{\cdot}7H_2O$ as magnesium salt were the most effective in the lipase production. 4. The addition of olive oil, soybean oil, and coconut oil respectively increased the enzyme production and especially 1% olive oil increased it by 50%. 5. The enzyme production increased slightly on the addition of yeast extract to $0.05{\sim}0.07%$. 6. The optimum composition of the medium for the lipase production by Rhizopus japonicus was in the composition of soybean meal 2%; $K_2HPO_4{\cdot}$ 0.5%; $(NH_4)_2SO_4$ 0.1%; $MgSO_4\;7H_2O$ 0.05%; yeast extract 0.05%; olive oil 1%. The maximum production of the lipase was attained by the incubation far 48hrs under the optimum incubation condition.

• KSBB Journal
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• v.11 no.3
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• pp.380-387
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• 1996

The growth of recombinant E. coli and formation of the by-products were investigated. Glucose was consumed in approximately 8hours of cultivation when initial glucose concentration was 5g/1. When higher initial glucose concentrations were employed, it took approximately 16 to 20hours for the glucose to be consumed. When maltose or glucose was used as a carbon source, lactic acid and acetic acid were main by-products, while propionic acid and methanol production was not significant. Much by- products were formed at the higher initial carbon source concentrations. Higher concentration of lactic acid was observed when glucose was used, while higher concentration of acetic acid was observed when maltose was used. Lactic acid production affected the cell yield while acetic acid production affected the growth rate.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.45-51
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• 2007

Arthrospira (Spirulina) platensis is one of the commercially important filamentous cyanobacteria. The heterotrophic cultivation of Arthrospira can be an alternative strategy for commercial mass production. In heterotrophic culture, the specific growth rate of A. platensis M9108, a glucose-resistant mutant of A. platensis PCC 9108, was $0.014h^{-1}$ which was 1.8 higher than that oi the previous report. The mutant possessed the facility to assimilate and to metabolize glucose efficiently under heterotrophic condition. However, the r-linolenic acid content of 6 Arthrospira strains was not increased in heterotrophic culture. Four Arthrospira strains out of 6 tested strains were able to utilize maltose as a carbon source under heterotrophic condition. The biomass production of these strains on maltose was similar to that on glucose. The specific growth rate of A. platensis M9108 increased with glucose concentration up to 5.0 g/L and then decreased at a glucose concentration of 10.0 g/L. Additionally, A. platensis M9108 under heterotrophic condition showed no aggregation during the cultivation in contrast to A. platensis PCC 9108.

• KSBB Journal
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• v.16 no.3
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• pp.246-252
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• 2001

We isolated a bacterium that produces an extracellular maltopentaose(G5)-forming amylase from amylose and soluble starch. The bacterium was identified and assigned as a Bacillus sp. AIR-5. The amylase did not hydrolyze maltose, maltotriose, maltotetraose or maltopentaose. Optimum medium composition for maltopentaose production in flask culture was 2%(w/v) soluble starch, 0.4%(w/v) tryptone, 0.5%(w/v) NaCl, 0.5%(w/v) K$_2$HPO$_4$, and 3 mM CaCl$_2$at pH 8.0, 28$^{\circ}C$. The highest yield for maltopentaose production in this condition was 6.45 g/L and was 32.55% of theoretical yield.