• Journal of Microbiology
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• v.41 no.3
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• pp.196-201
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• 2003

The object of this study was to characterize Bacillus strains GB-017 and GB-0356, which produce antifungal substances, especially for plant pathogens. In addition, this study was undertaken to characterize the culture conditions required for the production of antifungal substances and to document some of the properties of the antifungal substance produced by these soil-isolated strains. Strains GB-0365 and GB-017 were found to be bacillus-shaped, gram-positive and motile, and to inhibit Botrytis cineria, Fusarium sp., Pythium sp., and Rhizoctonia solani. Antagonistic activity was maintained up to pH 9.0, and the antifungal activity was stable to heat at 80$^{\circ}C$ for 1 h. Antifungal substances were separated and purified using ion exchange and adsorption columns including WK-I0(H$\^$＋) (pH 7.0), HP20 column (pH 3.0) and IPA (pH 3.0). and IPA. Its UV absorption spectrum showed major peaks at 231 and 259 nm, corresponding to polyene and lactone. A fast atom bombardment mass spectrum (FAB MS) showed a highest peak at 441 m/z and major peaks at 192, 205, and 370 m/z.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.357-362
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• 1988

Twenty-one aerobic bacteria were isolated from Kimchi and the influences of aqueous extract of garlic on the isolates were studied. The bacteria were 11 Bacillus spp., 2 Staphylococcus spp., a Micrococcus sp., a Flavobacterium sp., an Enterobacteriaceae, and 4 Vibrionaceae. In nutrient broth growth of the bacteria was inhibited by the extract. The antibacterial effects of the garlic were different from each other depending upon the bacteria. The results revealed that the inhibitory effects were due to the bacteriocidal action of the garlic extracts.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.76-83
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• 1999

Studies were conducted during 2 months from May of 1997 to evaluate the effects of pig manure compost(PMC) on soil microbial flora. To do so, a field experiment of Chinese cabbage(Brassica campestris L.) was conducted in a randomized block design on a sandy loam soil and microbial floral characteristics in soils were analyzed. Treatments to control included the application of PMC at (A) $8Mg\;ha^{-1}$CM-8), (B) $29Mg\;ha^{-1}$(CM-2,9), and (C) $57Mg\;ha^{-1}$(CM-57), and of chemical fertilizer(D) at $320N-80P_2O_5-200K_2O\;kg\;ha^{-1}$(NPK). In each treatment, the rhizosphere and non-rhizosphere soils were tested for the analysis of microbial populations. The populations of bacteria, actinomycetes, and fungi increased in soils with the applications of PMC and chemical fertilizer, but that of Bacillus sp. decreased. However, the population of fluorescent Pseudomonas sp. was reduced in NPK plots only. With increasing application rates of PMC, the number of colony forming units(cfu) of bacteria (Pseudomonas sp. and actinomycetes) and fungi increased. in all PMC-treated plots, the population density peaked at early growth stage for bacteria(including Bacillus sp.), at late growth for fluorscent Pseudomonas sp., and at harvest for fungi and actinomycetes. The rhizosphere effect was greatest for fluorscent Pseudomonas sp. As the application rates of PMC increased, Total N, organic matter, available phosphate, and exchangeable -K, -Ca, and -Mg increased compared to control, but soil pH was lowered. In NPK plots, EC was 3.4-fold and exchangeable K was 5-fold higher than control.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.54-60
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• 1987

Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) were tested for their effectiveness in inhibiting the growth of microorganisms. Among the test microorganisms, the growth of three yeasts (Saccharomyces cerevisiae, Kloeckera apiculata, Cryptococcus hungaricus), three bacteria (Bacillus subtilu, Lactobacillus cases, Escherichia colt) and two molds (Aspergillus oryzae. Penicillium sp.) was progressively decreased as concentrations of BHA were increased. A. oyzae was completely inhibited with 100ppm of BHA and a majority of the test microorganisms (S. cerevisiae, K. apiculata. C. hungaricus, B. subtilis, A. oryzae) were completely inhibited by 150 ppm of BHA. The growths of L. casei, E. coli and Penicillium sp. were not affected as much as those of other microorganisms by BHA. Final cell yiedls were becoming lower as the concentration of BHA increased. The growth of C. hungaricus and L. casci was slightly inhibited by BHT. Other microorganisms were not effected by the test concentrations of BHT.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.115-120
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• 2006

To convert the soybean curd residue (SCR) to functional food ingredient, alkaline fermentation of SCR was performed by Bacillus firmus NA-1 and Bacillus subtilis GT-D for 22 hr at $42^{\circ}C$. The micronized full-fat soy flour (MFS) was fortified to reduce the moisture content as well as to supply protein source. The mucilage and flavor productions in the fermented SCR were enhanced by the fortification of $20\%$ MFS. The peptide production from the SCR fermented with B. subtilis GT-D substantially increased when judged by the detectable amount of tyrosine $(480\;mg\%)$. The production of fibrinolytic enzyme was increased by the fermentation for 22 hr, indicating the relative activity of $62\%$ (B. firmus NA-1) and $47\%$ (B. subtilis GT-D), respectively. The SCR fermented by B. firmus NA-1 and B. subtilis GT-D indicated the consistency of $1.95\;Pa{\cdot}s^n\;and\;0.21\;Pa{\cdot}s^n$, respectively. After freeze-drying, the protease activity (615 unit/g) and a-amylase activity (180 unit/g) were obtained from SCR fermented by Bacillus firmus NA-1 and Bacillus subtilis GT-D, respectively.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.424-431
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• 2011

BACKGROUND: Tributyltin chloride is among the most toxic compounds known for aquatic ecosystems. Microorganisms are responsible for removal of TBTCl. Nevertheless, only a limited number of marine bacteria were investigated for biodegradation of TBTCl in Korea. METHODS AND RESULTS: The number of TBTCl resistant bacteria ranged from $2.5{\times}10^3$ to $3.8{\times}10^3$ cfu/mL in the seawater, and ranged from $3.2{\times}10^5$ to $9.1{\times}10^5$ cfu/g in the surface sediment, respectively. The morphological, physiological, and biochemical characteristics of TBTCl resistant bacteria were investigated by API 20NE and other tests. The most abundant species of TBTCl resistant bacteria were Vibrio spp. (19.2%), Bacillus spp. (16.2%), Aeromonas spp. (15.2%), and Pseudomonas spp. (13.1%), etc. Eleven TBTCl resistant isolates also had a resistance to heavy metals (Cd, Cu, Hg, and Zn). Among them, isolate T7 showing the strong TBTCl-resistance was selected. This isolate was identified as the genus Pantoea by 16S rRNA gene sequencing and designated as Pantoea sp. T7. In addition, this bacterium was cultivated up to the growth of 50.7% after 60 hrs at TBTCl concentration of $500{\mu}M$. TBTCl-degrading activity of Pantoea sp. T7 was measured by GC-FPD analysis. As a result of biological TBTCl-degradation at TBTCl concentration of $100{\mu}M$, TBTCl-removal efficiency of Pantoeasp. T7 was 62.7% after 40 hrs. CONCLUSION(S): These results suggest that Pantoea sp. T7 is potentially useful for the bioremediation of TBT contamination.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.35-42
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• 2003

A 1,3 kb cellulase gene encoding novel bifunctional cellulase-chitosanase activity was cloned from biopolymer-producing alkali-tolerant B. lichenformis NBL420 in E. coli. A recombinant cellulase-chitosanase, named CelA, was expressed and purified to homogeneity. The activity staining and the enzymatic characterization of the purified CeIA revealed bifunctional activities on carboxymethyl cellulose (CMC) and glycol-chitosan. The similar characteristics of the enzymatic activities at the optimum pH, optimum temperature, and thermostability Indicated that CelA used a common catalytic domain with relaxed substrate specificity. A comparison of the deduced amino acids in the N-terminal region revealed that the mature CelA had a high homology with the previously identified bifunctional cellulase-chitosanase of Myxobacter sp. AL- 1.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.712-715
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• 2001

A new combined method including the enzymatic hydrolysis of $\beta$-cyclodextrin ($\beta$-CD) and solvent extraction fo cholesterol from the hydrolyzed mixture was developed to recover cholesterol from a $\beta$-CD-cholesterol complex prepared from dairy products, such as cream, milk, and cheese. Cyclomaltodextrinase (cyclomatodextrin dextrin hydrolase, EC 3.2.1.54, DCase_ prepared form alkalophilic Bacillus sp. KJ 133 hydrolyzed the $\beta$-DC of the $\beta$-CD-cholesterol complex, and then, free cholesterol was efficiently extracted from the hydrolyzed mixture by a nonpolar solvent such as ethyl acetate. To increase the stability of free CDase, immobilized CDase was developed using sodium alginate as a carrier. The immobilized CDase showed a high recovery yield of cholesterol in a time-dependent manner compared to the free CDase. A gas chromatography analysis showed that more than 70% of cholesterol was recovered from the $\beta$-DC-cholesterol complex of cream by the immobilized CDase, whereas only 3% and 29% of cholesterol were recovered when the solvent extraction and free CDase treatment were used, respectively. The cholesterol recovered can be used as a raw material for steroid synthesis. Furthermore, this method can be an efficient way to recover cholesterol or other organic compounds that are bound in a $\beta$ -DC-cholesterol or -organic compound complex.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.460-465
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• 2016

The market for potato chips has expanded due to increased consumption of seasoned potato chips. However, the deep-frying process facilitates development of a browning color and formation of acrylamide. The objective of this work was to minimize browning color and acrylamide formation by fermentation prior to deep-frying. Potato slices were fermented by using three Bacillus strains, B. licheniformis (BL), B. methylotrophicus (BM), and B. subtilis, for 6 h at $30^{\circ}C$. In all fermentation groups, contents of total sugars in potato slices decreased. The color of fermented potato chips improved compared to the control. BM potato chips showed the best color values (76.33 in L value, 5.67 in a value, and 34.79 in b value). All fermentation processes reduced levels of acrylamide in deep-fried potato chips. Fermentation of potato slices for 2 h by BL reduced up to 96.1% acrylamide content. It was concluded that the fermentation process can positively affect color development and acrylamide formation.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1255-1261
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• 2006

An alkaliphilic bacterium, Bacillus sp. strain BK, was found to produce extracellular cellulase-free xylanolytic enzymes with xylan-binding activity. Since the pellet-bound xylanase is eluted with 2% TEA from the pellet of the culture, they contain a xylan-binding region that is stronger than the xylan-binding xylanase of the extracellular enzyme. The xylanases had a different molecular weight and xylan-binding ability. The enzyme activity of xylanase in the extracellular fraction was 6 times higher than in the pellet-bound enzyme. Among the enzymes, xylanase had the highest enzyme activity. When Bacillus sp. strain BK was grown in pH 10.5 alkaline medium containing xylan as the sole carbon source, the bacterium produced xylanase, arabinofuranosidase, acetyl esterase, and $\beta$-xylosidase with specific activities of 1.23, 0.11, 0.06, and 0.04 unit per mg of protein, respectively. However, there was no cellulase activity detected in the crude enzyme preparation. The hydrolysis of agricultural residues and kraft pulps by the xylanolytic enzymes was examined at 50$^{\circ}C$ and pH 7.0. The rate of xylan hydrolysis in com hull was higher than those of sugarcane bagasse, rice straw, com cop, rice husk, and rice bran. In contrast, the rate of xylan hydrolysis in sugarcane pulp was 2.01 and 3.52 times higher than those of eucalyptus and pine pulp, respectively. In conclusion, this enzyme can be used to hydrolyze xylan in agricultural residues and kraft pulps to breach and regenerate paper from recycled environmental resources.