• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1054-1059
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• 2005

An extracellular protease was identified from Bacillus subtilis KCCM 10257 by N-terminal sequencing and mass spectral analysis. The molecular mass of the extracellular protease was estimated to be 28 kDa by SDS-PAGE. Sequencing of the N-terminal of the protease revealed the sequence of A(G,S,R)QXVPYG(A)V(P,L)SQ. The N-terminal sequence exhibited close similarity to the sequence of other proteases from Bacillus sp. A mass list of the monoisotopic peaks in the MALDI-TOF spectrum was searched after peptide fragmentation of the protease. Six peptide sequences exhibiting monoisotopic masses of 1,276.61, 1,513.67, 1,652.81, 1,661.83, 1,252.61, and 1,033.46 were observed from the fragmented protease. These monisotopic masses corresponded to the lytic enzyme L27 from Bacillus subtilis 168, and the Mowse score was found to be 75. A doubly charged Top product (MS) at a m/z of 517.3 exhibiting a molecular mass of 1034.6 was further analyzed by de novo sequencing using a PE Sciex QSTAR Hybrid Quadropole-TOF (MS/MS) mass spectrometer. MS/MS spectra of the Top product (MS) at a m/z of 517.3 obtained from the fragmented peptide mixture of protease with Q-star contained the b-ion series of 114.2, 171.2, 286.2, 357.2, 504.2, 667.4, 830.1, and 887.1 and y-ion series of 147.5, 204.2, 367.2, 530.3, 677.4, 748.4, 863.4, and 920.5. The sequence of analyzed peptide ion was identified as LGDAFYYG from the b- and y-ion series by de novo sequencing and corresponded to the results from the MALDI-TOF spectrum. From these results the extracellular protease from Bacillus subtilis KCCM 10257 was successfully identified with the lytic enzyme L27 from Bacillus subtilis 168.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.132-138
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• 2019

Among several marine-derived microorganisms isolated from the coast of Jeju Island that had antimicrobial activity against fish disease pathogens, Bacillus subtilis MD-02 was tested for its dietary effect on the innate immune response and disease resistance of olive flounder. Strain MD-02 was fed to the olive flounder at a concentration of $1.2{\times}10^4$, $1.2{\times}10^6$, or $1.2{\times}10^8CFU/100g$, respectively. Consequently, the hematocrit was higher in these three groups than that in the control group at 4 weeks, and the aspartate aminotransferase and alanine aminotransferase levels were decreased in the $1.2{\times}10^8$ and $1.2{\times}10^4CFU/100$ groups compared with the control group levels. The amylase activity and total protein were significantly increased in the $1.2{\times}10^4CFU/100g$ group at 3 weeks. The innate immune response, determined from the lysozyme and macrophage activities, was higher in the $1.2{\times}10^8CFU/100g$ group than in the control group. In addition, treatment of the olive flounders with Streptococcus parauberis at $1.2{\times}10^6CFU/ml$ confirmed the mortality rate, which was 100% in the control group and 40-60% in the groups fed B. subtilis MD-02, indicating that the fish had resistance to fish disease pathogens. Therefore, it was confirmed that when fed MD-02, olive flounder builds an innate immune response and acquires resistance to fish disease pathogens, indicating that B. subtilis MD-02 can be developed as a beneficial feed additive.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.843-850
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• 2016

This study was conducted to investigate changes in isoflavone composition (glycosides and bio-active aglycones) and evaluate the quality characteristics of doenjang prepared using different Bacillus strains (KACC15935 and HJ18-9). After 60 days of fermentation, ${\beta}-glucosidase$ activity of doenjang fermented with B. subtilis HJ18-9 was higher than those of other samples. Contents of aglycones (daidzein, genistein, and glycitein) in B. subtilis HJ18-9 significantly increased up to $703.90{\pm}11.09{\mu}g/g$. In addition, total phenolic content and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity increased markedly during fermentation. These results suggest that fermentation with B. subtilis could be used to increase ${\beta}-glucosidase$ activity with a view towards development of functional foods.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.280-286
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• 2013

This study was performed to investigate the effect of types of microorganisms on the antioxidant activity of soybean yogurt by a single or mixed culture of Bacillus subtilis and Lactobacillus plantarum isolated from chunggukjang and kimchi. The fermented soybean milk by Bacillus subtilis exhibited the highest values of total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity compared to those of Lactobacillus plantarum or mixed culture of Bacillus subtilis/Lactobacillus plantarum. As the amount of tomato extract was added to the soybean milk, various antioxidant parameters, such as total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity, were linearly increased.

• KSBB Journal
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• v.16 no.4
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• pp.415-419
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• 2001

To produce staphylokinase (SAK) in B. subtilis WB700, media optimization was carried out and the operation of batch and fed-batch fermentation were compared. Tryptone is a good nitrogen source and its optimum concentration in modified super rich(MSR) media is 15 g/L. When glucose is used as a limiting carbon source in the MSR media, 5 g/L of an optimum glucose concentration was identified for the SAK production under the control of P43 promoter. As the expression of P43 promoter is controlled by the limitation of oxygen, the SAK production was controlled at the 30% DO level in the fed-batch fermentation. Unexpectedly, batch fermentation using MSR media showed 1.5 times higher yield of SAK than that of the fed-batch fermentation. The main cause of the results comes from not achieving higher cell concentration in the fed-batch fermentation and the optimum expression level of P43 promoter under oxygen or nutrient limitations. We could not achieve the increase in cell concentration by any means in batch culture as well as fed-batch culture. The highest yield in the batch culture was 2880 units of SAK activity and 455 mg/L of secreted SAK.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.36-45
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• 2012

To produce novel cheese-like fermented soybean, the solid-state fermentation of roasted soybean flour (RSF) was performed using 1.0% inoculum Bacillus subtilis HA and Lactobacillus plantarum, with the initial 60% substrate moisture for 10 hr at $42^{\circ}$, resulting in pH 6.5, 0.82% acidity, 3.5% mucilage, 14.3 unit/g protease activity, 7.6 unit/g fibrinolytic activity, 216 mg% tyrosine content and $1.7{\times}10^{10}$ CFU/g of viable cell counts. After the second lactic acid fermentation with 10~30% skim milk powder, the fermented RSF resulted in an increase in acidity with 1.64~1.99%, tyrosine content with 246~308 mg% and protease activity in the range of 5.2~17.5 unit/g and 0.966 water activity. Viable cell counts as probiotics indicated $1.6{\times}10^8$ CFU/g of B. subtilis and $7.3{\times}10^{10}$ CFU/g of L. plantarum. The firmness of the first fermented RSF with 2,491 $g{\cdot}{\o}mm^{-1}$ greatly decreased to 1,533 $g{\cdot}{\o}mm^{-1}$ in the second fermented RSF, although firmness was slightly increased by adding a higher content of skim milk. The consistency of the second fermented RSF also decreased greatly from 55,640 to 3,264~ 3,998 in the presence of 10~30% skim milk. The effective hydrolysis of soy protein and skim milk protein in the fermented RSF was confirmed. Thus, the second fermented RSF with a sour taste and flavor showed similar textural properties to commercial soft cheese.

• Microbiology and Biotechnology Letters
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• v.13 no.2
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• pp.103-107
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• 1985

A variety of plasmid curing agents such as sodium dodecyl sulfate, acriflavine, ethidium bromide, and mitomycin-C were used to cure Bacillus subtilis cells of streptomycin resistant factor. The drug susceptibility was increased by 0.1％ sodim dodecyl sulfate at stationary growth phase. The curing frequency was obtained highly at 4 $\mu\textrm{g}$/$m\ell$ of acriflavine, 10 $\mu\textrm{g}$/$m\ell$ of ethidium bromide, and 200 $\mu\textrm{g}$/$m\ell$ of mitomycin-C. respectively. Curing action occurred competitively for the streptomycin and terramycin resistant factors in B. subtilis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.108-114
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• 2017

This study was performed to evaluate the characterization of fermented mulberry leaf using Bacillus subtilis by focusing on protein degradation and antioxidant activity. The crude protein and total amino acid compositions of mulberry leaf were 21.40% (w/w) and 105.06 mg/g, respectively. The pH level decreased sharply in mulberry leaf extracts fermented using B. subtilis, in accordance with an increase in bacteria cell populations (9.49 log CFU/mL) during 36 h of fermentation. The protease activity of mulberry leaf increased to 97.45 units/mL after 5 days of fermentation. After fermentation, free amino acid contents in fermented mulberry leaf increased from $486.91{\mu}g/g$ to $644.35{\mu}g/g$ due to considerable elevation of isoleucine (6-fold), alanine (4.67-fold), leucine (4.52-fold), and valine (4.21-fold). The DPPH radical scavenging activity of fermented mulberry leaf also increased from 25.93% to 73.22% after 5 days of fermentation. These results suggest that mulberry leaf fermentation using B. subtilis can improve nutritional quality and antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.291-296
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• 2003

Effects of Bacillus subtilis and Rhizopus oryzae on chitooligosaccharides (COS) content of doenjang (soybean paste) and kanjang (soy sauce) were investigated using kojis made with the two strains. Competitive direct enzyme-linked immunosorbent assay (cdELISA) system using anti-COS mixture (COSM) antibody was applied for COS detection ranging from 0.001 to $1{\mu}g/mL$, and the recoveries of COSM spiked to doenjang and kanjang were 102 and 115%, respectively. Doenjang and kanjang products made with a mixture of B. subtilis and R. oryzae kojis showed COS contents of 171 and $29{\mu}g/mL$, respectively, during two-month aging period, much higher than those of Japanese and Korean commercial ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.21-26
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• 1991

the Bacillus subtilis LY-353 which secretes the protease isolated from seafoods. The opti-mum culture condition for production of protease from B. subtilis LY-353 was as follows ; tem-perature 35$^{\circ}C$ pH 7.5 salt concentration 1.0% The purification steps involved ammonium sulfate fractionation DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration A 7.33 fold purification and 6.55 yield of protease was obtained from culture broth, The optimum pH and temperature for the enzyme action were pH7.5 and 55$^{\circ}C$ respecti-bely.