PROCESS BIOCHEMISTRY
·
2022
·
IF 4.885
Chengchen Cai,Ming Zhang,Haiming Chen,Wenxue Chen,Weijun Chen,Qiuping Zhong
Mango juice (MJ) has high nutritional value and decent flavor. However, its aroma could be easily changed by heat treatment during processing, which affects its acceptability and quality. In this study, Bacillus subtilis -HNU-B3 that could transfer carotenoid, was obtained from orchard soil to improve the aroma of fermented mango juice (FMJ). Compared with MJ, the organic acid content of FMJ by B. subtilis -HNU-B3 was significantly changed, and the contents of succinic acid and malic acid were increased to 3.68 mg/mL and 2.04 mg/mL, respectively. Moreover, volatile compounds identified by headspace solid-phase micro-extraction gas-phase mass spectrometry in FMJ were norisoprenoid and acetoin, accounting for 51.52 % of the total volatile substances. In addition, B. subtilis -HNU-B3 fermentation significantly increased the antioxidant capacity and total phenol contents of MJ, and the activity of carotenoid cleavage dioxygenase was 188 U/L. In conclusion, the aroma of FMJ could be improved by B. subtilis -HNU-B3 through increasing the content of norisoprenoid and acetoin. Our results provide theatrical support for Bacillus subtilis to improve the aroma quality of FMJ.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2016
·
IF 2.189
Xiqian Sheng,Ming Yan,Lin Xu,Miao Wei
We identified and characterized YqiG, a novel Old Yellow Enzyme (OYE) from Bacillus subtilis str.168 , as a member of the “thermophilic-like” subfamily. It is most related to XenA from Pseudomonas putida , with 37.9% identity, but it exhibits certain differences in sequence and enzyme properties. The YqiG can reduce various activated alkenes and exhibits high temperature (60 °C for 12 h) and pH stability (pH 4.0 and 9.0 for 12 h), which indicates that it has a great potential for biocatalysis. However, it shows low tolerance toward organic solvents. Also the YqiG shows high activities towards maleimide, dimethyl maleate and acyclic ketones (55.5 U/mg, 6.22 U/mg and 2.97 U/mg, respectively). Besides, The YqiG can catalyze citral to (S)-citronellal with a low rate but high ee% (>99%).
研究领域:
生物化学
·
酶学
·
微生物学
✓ 已验证
DOI
高影响因子
FEBS Open Bio
·
2020
·Vol. 10
·期 12
·2733-2739
·
IF 2.231
Sai-sai Ding,Jin-peng Zhu,Yang Wang,Bin Wu,Zongpei Zhao
In the paper industry, chlorine is often used to treat the pulp for bleaching. After pulping, a large amount of xylan is present in the fiber. Xylanase can be used to degrade xylan in an eco-friendly process called biobleaching, which can help minimize the usage of chlorine in the delignification process. However, a bottleneck in the adoption of biobleaching is the cost of xylanase and the requirement that xylanase be active and stable at extreme conditions. Here, we investigated whether using sodium alginate beads to immobilize an extracellular xylanase from Bacillus subtilis (Lucky9) can reduce the potential cost of enzyme usage. The optimal pH and the activity of the immobilized enzyme were increased at optimal temperature compared with the free enzyme. In addition, immobilized xylanase was shown to be more stable than free xylanase. The results of this study suggest that the immobilized xylanase has potential applications in the biobleaching industry.
研究领域:
生物技术
·
酶工程
·
制浆造纸工业
✓ 已验证
DOI
PubMed
高影响因子
FEMS MICROBIOLOGY LETTERS
·
2018
·Vol. 365
·期 7
·
IF 1.735
Qian Bingjun,Yin Lirong,Yao Xiaomin,Zhong Yaoguang,Gui Juan,Lu Feifeng,Zhang Fuming,Zhang Jianhua
The saponins, as components of tea seed meal, are undesirable hemolytic components and should be degraded for reducing their hemolytic activity in order to be used in animal feed. In this study, β-glucuronidase was verified to be a potent hydrolase of tea seed saponins to reduce their hemolytic activity and a β-glucuronidase-producing Lactobacillus crustorum strain was screened from raw bovine milk. Next, solid-state fermentation with the isolated L. crustorum and a Bacillus subtilis natto strain, which can produce cellulase and hence improve the fermentation performance of tea seed meal, was carried out for detoxification of tea seed meal. The 50% hemolytic dosage (HD50) value of tea seed saponins was increased from 6.69 to 27.43 μg mL−1. The results of LC–MS analysis showed that the percentage of saponin aglycones increased from 30.95 to 84.25% after the fermentation. According to the roles of sugar moieties in hemolytic activity, and the enzymatic hydrolysis characteristics of β-glucuronidase, the degradation of tea seed saponins from glucosides to aglycones may contribute to the reduction of hemolytic activity. Therefore, tea seed meal may be used as animal feed after fermentation with the tested saponin-degrading microbial strains.
研究领域:
微生物学
·
动物营养学
✓ 已验证
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2021
·Vol. 232
·期 6
·1-14
·
IF 2.52
Zhang Sinan,Wang Jihong
Biochar-immobilized microorganism technology is an effective way to remove antibiotic contamination in aqueous solutions. In this study, the effect and mechanism of immobilization of Bacillus subtilis by honeysuckle residue–derived biochar for the removal of chlortetracycline (CTC) were investigated using corn straw biochar as a comparison. The biochar’s structural characteristics and properties were determined using scanning electron microscopy, X-ray diffractometer, Fourier-transform infrared spectrometer, specific surface area, and pore size analyzer. It was found that honeysuckle residue–derived biochar had a well-developed pore structure, which provided adequate living space for microorganisms. The removal rate of CTC (50 mg/L) by honeysuckle residue biochar-microbial complex (HBCM) was 15.31% higher than that of corn straw biochar-microbial complex, indicating that HBCM was an excellent carrier. The mechanism of CTC removal by HBCM was a synergistic effect of biochar adsorption and microbial degradation. The removal process of HBCM material was carried out for 3 days at an optimum substrate concentration of 50 mg/L, an ambient temperature of 35 °C, a solution pH of 7, and the addition of 5 g/L complexes, achieving a removal rate of 78.35%. In addition, the complex possessed high storage stability and could be reused three times continuously and efficiently. This study provides a method for preparing an efficient biochar-microbial complex using Chinese medicine residue waste substrate, which provides a new idea for removing CTC from water.
研究领域:
环境科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2022
·Vol. 88
·期 19
·
IF 5.005
Shuai Liu,Yuwei Gao,Lin Quan,Mei Yang,Yong-Zhong Wang,Changjun Hou
An increase in exoenzyme production can be enhanced by environmental stresses such as graphene oxide (GO) stress, but the link between the two events is still unclear. In this work, the effect of GO as an environmental stress factor on exoenzyme (lignocellulolytic enzyme, amylase, peptidase, and protease) biosynthesis was investigated in Bacillus subtilis Z2, and a plausible mechanism by which cytosolic Ca2+ regulates lignocellulolytic enzyme production in B. subtilis Z2 subjected to GO stress was proposed. The filter paper-hydrolyzing (FPase [representing total cellulase]), carboxymethylcellulase (CMCase [representing endoglucanase]), and β-glucosidase activities and extracellular protein concentration of the wild-type strain under 10 μg/mL GO stress were 1.37-, 1.64-, 1.24-, and 1.16-fold those of the control (without GO stress), respectively. Correspondingly, the transcription levels of lignocellulolytic enzyme genes, cytosolic Ca2+ level, and biomass concentration of B. subtilis were all increased. With lignocellulolytic enzyme from B. subtilis used to hydrolyze alkali-pretreated rice straw, the released reducing sugar concentration reached 265.53 mg/g, and the removal rates of cellulose, hemicellulose, and lignin were 52.4%, 30.1%, and 7.5%, respectively. Furthermore, transcriptome data revealed that intracellular Ca2+ homeostasis played a key role in regulating the levels of gene transcription related to the synthesis of lignocellulolytic enzymes and exoenzymes. Finally, the use of Ca2+ inhibitors (LaCl3 and EDTA) and deletion of spcF (a calmodulin-like protein gene) further demonstrated that the overexpression of those genes was regulated via calcium signaling in B. subtilis subjected to GO stress.IMPORTANCE To effectively convert lignocellulose into fermentable sugars, high lignocellulolytic enzyme loading is needed. Graphene oxide (GO) has been shown to promote exoenzyme (lignocellulolytic enzyme, amylase, peptidase, and protease) production in some microorganisms; however, the regulatory mechanism of the biosynthesis of lignocellulolytic enzymes under GO stress remains unclear. In this work, the lignocellulolytic enzyme production of B. subtilis under GO stress was investigated, and the potential mechanism by which B. subtilis enhanced lignocellulolytic enzyme production through the calcium signaling pathway under GO stress was proposed. This work revealed the role of calcium signaling in the production of enzymes under external environmental stress and provided a direction to facilitate lignocellulolytic enzyme production by B. subtilis.
研究领域:
微生物学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2023
·
IF 5.2
Kaiyong Yao,Qile Xia,Yan Cao,Bindan Chen,Jie Cai,Chenxing Liu
Yellow wine lees (YWL) are the main byproduct in the yellow wine brewing and can be used as animal feed. The deficiencies in fiber digestibility and amino acid equilibrium of YWL limited its utility value in animal feeding. The nutritional profile of YWL could be moderated after fermentation treatment. We fermented YWL with Candida utilis KF01 and Bacillus subtilis KF02, whose genomes were sequenced. We set three groups in the animal test with 15 Holstein cows : control, YWL, and fermented yellow wine lees (FYWL) group. 206 and 5 amino acid metabolism-related KEGG pathways, as well as 5257 (639 GO and 4618 eggNOG annotations) and 1579 (372 GO and 1207 eggNOG annotations) amino acid metabolism-related gene annotations were found in C. utilis KF01 and B. subtilis KF02. The collected milk samples were analyzed for composition. The contents of mono-unsaturated fatty acid (MUFA, 36.90% relative content), poly-unsaturated fatty acid (PUFA, 5.63% relative content), and essential amino acid (EAA, 2.01%) in the FYWL group milk were significantly (P < 0.05) higher. The content of flavor substances in the FYWL group (146.33 ng/mL) was the highest, followed by the control (89.19 ng/mL) and the YWL group (41.36 ng/mL). The principal component analysis (PCA) result presented the intra-group variations in flavor substances and differences in single substance among all groups. Feeding FYWL had significant effects (P < 0.05) in the Holstein cows on the milk composition.
研究领域:
动物营养学
·
微生物学
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD SCIENCE AND BIOTECHNOLOGY
·
2017
·Vol. 26
·期 1
·143-152
·
IF 0.699
Chen Peng,Yan Lei,Zhang Shuang,Wu Zhengrong,Li Suyue,Yan Xiaojuan,Wang Ningbo,Liang Ning,Li Hongyu
A stirring bioreactor packed with a carbon fiber textiles (FT) biofilm formed by Bacillus subtilis was used to produce vanillin from ferulic acid. Biofilm formation was characterized by scanning electron microscopy. The interactive effects of three variables on vanillin molar yield (M) and conversion efficiency of ferulic acid (E) were evaluated by response surface methodology (RSM) with a Box-Behnken design (BBD). The optimal conversion conditions with a maximum overall desirability D of 0.983 were obtained by a desirability function. Considering the actual operation, the confirmation tests were performed using the slightly modified optimal conditions (initial ferulic acid concentration 1.55 g/L, temperature 35°C, stirring speed 220 rpm). The results showed that M and E were 57.42 and 93.53%, respectively. This was only 1.03% and 1.87%, respectively, different from the predicted values, confirming the validity of the predicted models. These revealed that the stirred packed reactor could be successfully used in vanillin bioconversion from ferulic acid.
研究领域:
生物工程
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LETTERS IN APPLIED MICROBIOLOGY
·
2014
·Vol. 59
·期 3
·306-312
·
IF 1.749
Meng F.,Ma L.,Ji S.,Yang W.,Cao B.
Bioconversion of biomass, particularly crop wastes, into biofuels is being developed as an alternative approach in meeting the high energy demand. In this study, a thermophilic bacterial strain BY‐3 that exhibits cellulolytic potential was isolated from faecal samples of Tibetan pigs; this strain was identified as Bacillus subtilis. The strain can produce cellulase when grown on various substrates, including carboxymethyl cellulose, rice straw, corn stover, soluble starch and wheat bran. The maximum cellulase activity of the strain was up to 4·323 ± 0·065 U ml−1 when cultivated in the medium containing corn stover (30 g l−1) for 24 h. The results demonstrated that corn stover is the most suitable substrate for cellulase production by the strain BY‐3. The crude cellulase of strain BY‐3 was most active at pH 5·5 and 60°C, and the enzyme in acetate buffer (50 mmol l−1) demonstrated a good stability at 60°C for at least 1 h. The crude cellulase exhibited a strong antibacterial activity against Staphylococcus aureus. The strain can be used in cost‐efficient cellulase production for bioconversion of agricultural residual biomass into biofuels.Significance and Impact of the StudyThe increased consumption of fossil fuels has caused serious energy crisis and environmental problem. Thus, an alternative energy source is necessary. Bioconversion of biomass, particularly agricultural residuals, into value‐added bioproducts, such as biofuels and chemical solvents, has received considerable attention. In this study, the newly isolated thermophilic Bacillus subtilis strain BY‐3 produces cellulase efficiently with the use of untreated corn stover as a sole carbon source. This strain possesses the thermostable cellulase that is active with diverse crop wastes with a broad pH range and is a highly promising candidate for agricultural waste management.
研究领域:
微生物学
·
生物技术
·
可再生能源
✓ 已验证
DOI
高影响因子
Food Bioscience
·
2024
·
IF 4.8
Jun Huang,Yaoyao Su,Xiaoman Chen,Gang Yang,Zhirong Wang,Kewei Chen,Muying Du,Zsolt Zalán,Ferenc Hegyi,Jianquan Kan
Sterigmatocystin (STC), a mycotoxin that pollutes wheat and other grains and is related to health risks, has attracted increasing attention. In this study, we have explored the toxicity conditions of Aspergillus versicolor in wheat and identified a potential biological control method. By constructing a water activity (Aw)-water content curve, the effects of temperature, Aw, and culture time on toxin production by A . versicolor in wheat were determined. The Aw was found to be 0.96, and the concentration of STC in wheat reached the maximum (105.7 mg/kg) after 10 d of culture at 28 °C. Biocontrol bacteria were screened using plate confrontation, agar diffusion, and co-culture in wheat. The results showed that Bacillus subtilis HJ4 has significant antifungal activity against A. versicolor in vitro and in vivo . In vivo experiments showed that B. subtilis HJ4 significantly reduced the toxicity of A. versicolor to wheat (51%) on day-7, but the control effect was weakened (10%) on day-20. Finally, research on the antifungal mechanism of B. subtilis HJ4 revealed that its action primarily relies on competition for space and nutrients, destroying the cellular structure of the fungus and secreting substances with antifungal activity, such as proteins, cyclic lipopeptides, and oligosaccharides, aiding in control against A. versicolor . In summary, this study has emphasized the influence of environmental factors on the growth and toxin production of A. versicolor in wheat and evaluated the potential of B. subtilis HJ4 in reducing the pollution caused by A. versicolor and STC in wheat.
研究领域:
食品科学
·
微生物学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Diandi Li,Haijun He,Zhongxuan Xu,Hong Deng
Coexistence of chromium and iron, manganese and copper in industries is common, which may affect the microbial treating efficiency and toxicity to microorganisms, thus restricting the application of microbial treatment technology. In this research, Cu 2+ promoted the reduction of Cr(VI) and the fixation of total chromium in bimetallic systems for both Shewanella oneidensis MR-1 and Bacillus subtilis , while Mn 2+ and Fe 3+ exhibited inhibition effects. Generally, groups with coexisting heavy metal of 0.1 mM were most affected, no matter promotive or inhibitive. Toxicity analysis revealed that high concentration of heavy metal ions led to damage to the cell membranes and reduction of their survival rate. To clarify the optimal condition for microbial treatment, response surface methodology was used to investigate the influencing factors of Cr(VI) reduction by S. oneidensis . The total chromium concentration in the supernatant was correlated with three factors, and the significant order of influence was: culture time > culture temperature > pH.
研究领域:
微生物学
·
环境科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2025
·Vol. 15
·期 30
·24437
·
IF 4.6
Feng Wen,Yongjun Wu,Jing Jin,Lincheng Zhang,Shuoqiu Tong,Cen Li,Li Ran,Yuzhang Zhu
Fermented soybean products are an integral part of the Chinese diet, valued for their distinctive aroma. Bacillus subtilis ( B. subtilis ) BJ3-2 is a highly effective fermentation strain widely used in the industrial production of bacterial-type douchi. However, the specific aroma characteristics of soybeans fermented by this strain remain unclear. This study utilized gene knockout, GC-O-MS, and multivariate statistical analysis to comprehensively investigate the aroma components of soybeans fermented by B. subtilis BJ3-2. For the first time, 12 key aroma skeleton compounds were identified, including guaiacol, 2,5-dimethylpyrazine, and 2-methylbutyric acid, which primarily contribute to the smoky, roasted, and sweaty aroma attributes of fermented soybeans. Additionally, 17 compounds were considered to have important coordinating effects on soybean aroma, such as 3-hydroxy-2-butanone (buttery, creamy). Partial least squares regression (PLSR) analysis demonstrated a good correlation between key aroma compounds and sensory attributes. Gene knockout of fadA and bkdB resulted in a significant increase in 2,5-dimethylpyrazine and 1-octen-3-ol levels, along with a marked reduction in 2-methylbutyric acid levels. These changes enhanced the roasted and beany notes, reduced the sweaty aroma, and ultimately improved the overall aroma profile. These findings provide insights into the genetic regulation of aroma in fermented soybean products and form a foundation for reducing undesirable aromas and improving the overall aroma quality of industrially produced douchi. Bacillus subtilis fermented soy food is deeply loved by consumers, and its unique aroma characteristics are influenced by the fadA and bkdB genes.
研究领域:
食品科学
·
微生物学
·
分子生物学
·
感官分析
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）