• 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.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.423-428
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• 1990

Three strains among 8 isolates from the fermented chungkookjang were shown the strong phytase productivities. The phytase activities in manufacturing chungkookjang with thrse bacteria were maximized after incubating at 35-$40^{\circ}C$, pH 7.0 for 5 day. The contents of same amino acids and riboflavin were increased in chungkookjang manufactured with these phytase-producing bacteria and the rate of phytic acid degradation was much higher in chungkookjang manufactured with a single or mixed cultures of these bacteria than in traditional chungkookjang.

• KSBB Journal
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• v.9 no.3
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• pp.306-311
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• 1994

Optical resolution of racemic ${\alpha}$-methylbenzylamine was carried out by using Bacillus licheniformis protease in organic media. Enantioselective amidation of racemic amino with an ester as an acyl donor was successfully employed to resolve the racemate. To enhance reaction rate and enantioselectivity, pH-adjustment by lyophilization of enzyme dissolved in buffer, colyophilization with salts or lyoprotectants, selection of solvents and molecular design of esters were investigated. The optimization of the resolution reaction achieved about 30-fold increase in initial reaction rate and about 12-fold increase in enantioselectivity, respectively.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.300-307
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• 2015

For selecting Bacillus strains producing high-quality Cheonggukjang, 8 strains were isolated from the different Cheonggukjang samples. Seven of them exhibited the highest 16S rRNA gene sequence similarity value of over 99.9% to Bacillus subtilis subsp. subtilis and one of them showed the similarity to B. licheniformis. All the strains showed positive activities for amylase, cellulase, protease and lipase, and 6 strains are positive for fibrinolytic activity. To confirm the safety of the strains isolated from the samples of Cheonggukjang which are manufactured by traditional method, strains were analyzed for the presence of seven toxin genes of Bacillus cereus and results were found negative. And 7 strains did not produce at all or merely produce both histamine and tyramine, the representative biogenic amines. Biogenic amine degradation analysis by HPLC revealed that, most of them exhibited tyramine degradation activity. For Cheonggukjang fermented by artificial inoculation of selected strains, fermentation property, sensory test, volatile basic nitrogen production and metabolic profiles by $^1H-NMR$ were tested. Seven strains were confirmed to make high-quality Cheonggukjang.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1314-1327
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• 2021

Bacillus is characterized by the formation of spores in harsh environments, which makes it suitable for use as a probiotic for feed because of thermostability and high survival rate, even under long-term storage. This study was conducted to investigate the effects of Bacillus-based probiotics on growth performance, nutrient digestibility, intestinal morphology, immune response, and intestinal microbiota of weaned pigs. A total of 40 weaned pigs (7.01 ± 0.86 kg body weight [BW]; 28 d old) were randomly assigned to two treatments (4 pigs/pen; 5 replicates/treatment) in a randomized complete block design (block = BW and sex). The dietary treatment was either a typical nursery diet based on corn and soybean meal (CON) or CON supplemented with 0.01% probiotics containing a mixture of Bacillus subtilis and Bacillus licheniformis (PRO). Fecal samples were collected daily by rectal palpation for the last 3 days after a 4-day adaptation. Blood, ileal digesta, and intestinal tissue samples were collected from one pig in each pen at the respective time points. The PRO group did not affect the feed efficiency, but the average daily gain was significantly improved (p < 0.05). The PRO group showed a trend of improved crude protein digestibility (p < 0.10). The serum transforming growth factor-β1 level tended to be higher (p < 0.10) in the PRO group on days 7 and 14. There was no difference in phylum level of the intestinal microbiota, but there were differences in genus composition and proportions. However, β-diversity analysis showed no statistical differences between the CON and the PRO groups. Taken together, Bacillus-based probiotics had beneficial effects on the growth performance, immune system, and intestinal microbiota of weaned pigs, suggesting that Bacillus can be utilized as a functional probiotic for weaned pigs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.357-363
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• 2000

고추장의 품질을 향상시키고 재래식 전통 고추장과 유사한 맛을 지닌 고추장을 만들기 위해 재래식 전통 고추장에서 분리한 B.licheniformis 균주와 공장에서 대량 생산을 위해 개량해온 A. oryzae와, 비교적 호염성이며 알콜 발효 능력이 우수한 S.rouxii를 혼용하여 고추장을 담근 후 180일까지의 각 고추장의 이화학적 특성 변화를 조사한 결과는 다음과 같다. 단도는 모든 구에서 숙성 30일 까지 급격히 증가한 후 180일까지 거의 일정한 수준을 유지하였으며, 곰팡이 단용구에 비해 고초균과 효모 혼용구에서 숙성 기간 동안 높은 적정산도 값을 보였다. 조단백질은 숙성 기간 동안 대조구에서는 숙성 60일까지 약간 증가한 후 숙성 120일까지 급격히 감소하였으며 고초균 혼용구와 효모 첨가구는 숙성 90일 이후 감소한 후 숙성 120일 이후부터는 거의 변화가 없었다. 숙성 90일 이후부터는 B. licheniformis와 효모 혼용구에서 A. oryzae 단용구보다 조단백질 함량이 높았다. 환원당은 세 구간 모두 숙성 60일 경까지는 증가하는 추세를 보였으며, A. oryzae 단용구보다 B.licheniformis 균주와의 혼용구에서 높은 수치를 보여주었다. 비휘발성 유기산은 숙성 기간이 경과하면서 증가하였고 가장 많이 검출된 유기산은 pyroglutamic acid와 citric acid의 순이었다. 따라서 고추장의 숙성 과정 중 이화학적 특성 변화의 측면에서 볼 때 고초균과 효모 혼용구로 제조된 고추장이 구수한 맛의 생성면에서 유용한 담금법인 것으로 사료된다.

• The Plant Pathology Journal
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• v.29 no.2
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• pp.201-208
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• 2013

Drought stress is one of the major yield affecting factor for pepper plant. The effects of PGPRs were analyzed in relation with drought resistance. The PGPRs inoculated pepper plants tolerate the drought stress and survived as compared to non-inoculated pepper plants that died after 15 days of drought stress. Variations in protein and RNA accumulation patterns of inoculated and non-inoculated pepper plants subjected to drought conditions for 10 days were confirmed by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and differential display PCR (DD-PCR), respectively. A total of six differentially expressed stress proteins were identified in the treated pepper plants by 2D-PAGE. Among the stress proteins, specific genes of Cadhn, VA, sHSP and CaPR-10 showed more than a 1.5-fold expressed in amount in B. licheniformis K11-treated drought pepper compared to untreated drought pepper. The changes in proteins and gene expression patterns were attributed to the B. licheniformis K11. Accordingly, auxin and ACC deaminase producing PGPR B. licheniformis K11 could reduce drought stress in drought affected regions without the need for overusing agrochemicals and chemical fertilizer. These results will contribute to the development of a microbial agent for organic farming by PGPR.

• Research in Plant Disease
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• v.8 no.3
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• pp.184-188
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• 2002

An antagonistic bacteria, Bacillus licheniformis Nl strain which effectively inhibited mycelial growth of gray mold rot pathogen, Botrytis cinerea was isolated from the rhizosphere of perilla crop. Powder soy formulation by B. lichentfomis Nl strain as a biocontrol agent was developed far the first time and estimated its control effect on perilla leaves in this study. First of all, far the mass production of antifungal metabolites of B. lichentfomis Nl strain in flask liquid culture, the most effective carbon and nitrogen source were selected as glucose and tryp-tone, respectively, For the formulation, vegetative biomass of B. licheniformis Nl strain from 5-day-old liquid culture in nutrient broth added glucose and tryptone was mixed with soy flour, rice flour glucose, FeSo$_4$~7$H_2O$, and MnCl$_2$. 4$H_2O$, and dried and pulverized. In plastic house test, powder soy formulation effectually controlled gray mold rot as the control value of 93.1 %, was more effective than chemical fungicide, benomyl showing the control value of 86.1%. Thus, development of powder soy formulation of B. lichentfomis Nl will aid large-scale application of biological control in field trials.

• Journal of Sericultural and Entomological Science
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• v.34 no.2
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• pp.41-51
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• 1992

In this thesis, both soap and enzymatic degumming method were adopted and the optimum degumming conditions were obtained. Difference between the two degumming methods in silk fiber state was investigated and analyzed on the basis of the results of physical testings, polarizing microscopy, scanning electron microscopy, viscosity measurement, (${\alpha}$＋$\varepsilon$) amino group contents measurement, birefringence measurement, amino acid analysis, thermal analysis, infrared spectroscopy and x-ray diffraction analysis. The results obtained were summarized as follows; Physical test results of the degummed silk fiber showed that the tenacity and the elongation of enzymatic degummed silk fiber were lower than those of soap degummed fiber. But SEM observation and amino acid analysis showed almost the same tendency in the two degumming methods. The viscosity of enzymatic degummed silk fiber was lower than that of soap degummed fiber, but (${\alpha}$＋$\varepsilon$) amino group contents was higher in the enzymatic degummed fiber. It can be suggested that the enzymatic degummed silk fibroin was more degraded than the soap degummed fibroin. The birefringence, endothermic temperature of DSC spectrum, IR crystallinity and X-ray lateral order factor of enzymatic degummed silk fiber were higher than those of soap degummed fiber. It seems that the enzymatic degummed silk fiber has the higher crystallinity than that of soap degummed one according to the above results. However, it can be inferred that these differences between soap and enzymatic degummed fiber would be lessened if pretreatment and aftertreatment were included in the enzymatic degumming process.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.60-68
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• 1993

It has been known that the silk degumming treated by hot alkali solution is easy to handle but is liable to yield poor-quality silk due to the degree of degumming loss, incomplete-degumming or over-degumming. Therefore, many studies have been carried out on the silk degumming by enzyme in order to improve the quality of silk. However, no attention has been paid to the physicochemical analysis of enzymatic degummed silk. In this paper, two different degumming methods, soap and enzymatic, are compared in aqueous solution state of silk fibroin. The results can be summarized as follows: There was no significant difference between two solutions on the bases of polarizing microscopy, TEM observation and SDS-PAGE. Spherulite of silk fibroin was not observed in polarizing microscopy, however the leaf-shape fibril structure was developed upon solidification. The size of spherulites of silk fibroin in TEM observation were 30~120nm with a wide range of size distribution. The intrinsic viscosity of enzymatic degummed fibroin solution was lower than that of soap degummed solution. This can be explained that the silk fibroin was more degraded by enzymatic degumming method compared with the soap degumming method. SDS-polyacrylamide gel electrophoresis showed that the fibroin molecule was composed of large component of molecule weight above 50 kd and small component of molecule weight about 20 kd. There was no difference in crystallinity between two degumming methods on the bases of results of DSC thermograms and IR spectra.