STARCH-STARKE
·
2017
·
IF 1.837
Zixing Dong,Xiaoming Hao,Daman S. Pokhrel,Xiaoling Chen,Xiaoguang Liu,Nokuthula P. Mchunu,Kugenthiren Permaul,Suren Singh,Dandan Niu,Zhengxiang Wang
High-glucose syrup has wide applications in the feed and fermentation industries. However, during its regular production process, because of the slow hydrolysis of α-1,6-glucosidic linkages in maltodextrins by glucoamylase, yields of glucose higher than 96% are rarely achieved. To find a suitable enzyme for the saccharification process, two novel genes encoding oligo-1,6-glucosidases (OGL, EC 3.2.1.10) from Bacillus mycoides ( bmogl ) and Thermomyces lanuginosus ( tlogl ) were successfully cloned and overexpressed in Pichia pastoris GS115. At the shake-flask fermentation level, the OGL activities of the two recombinants GS115 (pPIC9K- bmogl ) and GS115 (pPIC9K- tlogl ) were 994 and 1219 U/mL, respectively; and mature enzymes around 66–68 kDa were purified for characterization. Recombinant enzyme TlOGL exhibited higher thermostability than ever reported for OGLs, whereas BmOGL was stable under acidic pH, ranging from 4.0 to 8.0. Among the substrates tested, these two recombinant enzymes efficiently hydrolyzed isomaltose and isomaltotriose, but had no activity against maltose and maltotriose. Besides these characteristics, nearly complete hydrolysis of isomaltotriose and 90% of isomaltooligosaccharides (IMOs) into glucose was also observed for them, which makes them good candidates for subsequent use in improving the yield of glucose from starch. To the best of our knowledge, this is the first report on the expression and characterization of OGLs from B. mycoides and T. lanuginosus .
研究领域:
生物化学
·
分子生物学
·
工业酶学
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Peng Shudong,Chaoqun Guo,Songjie Wu,Hongchang Cui,Huayi Suo,Zhi Duan
The purpose of this paper was to evaluate the potential of plant-based drink based on soy protein and fructooligosaccharide in the development of probiotic beverages after fermentation by Bacillus coagulans VHProbi C08. B. coagulans VHProbi C08 was isolated from sour cabbage, and the sporulation rate was 90.03%. After being treated at 95 °C for 15 min, the survival rate was 6.86 log CFU/mL. The whole gene of VHProbi C08 contains only one chromosome, 4123 protein-coding genes are predicted, and 824 genes are unique. Plant-based drink fermented by VHProbi C08 showed the highest antibacterial activity against B. cereus ATCC 14579, followed by S. aureus ATCC 29213, L. monocytogenes ATCC 19115, S. enteritidis ATCC 14028, V. parahaemolyticus ATCC 17802, and E. coli ATCC 25922. Its DPPH radical scavenging activity, hydroxyl radical scavenging activity and anti-lipid peroxidation activity were 0.39, 0.25 and 0.35 mmol Trolox/L, respectively. After UPLC-MS/MS detection and analysis; 17 major metabolites with significant changes in fermented and unfermented plant-based drink were identified, including 2-Hydroxycinnamic acid, d -Glucarate, L-Tryptophan, Deoxycytidine, Imidazole propionic acid, Hypoxanthine, etc. In addition, the properties of plant-based drink fermented by VHProbi C08 was relatively stable during storage.
研究领域:
食品科学
·
微生物学
·
生物化学
✓ 已验证
DOI
高影响因子
BIOLOGICAL CONTROL
·
2023
·
IF 4.2
Yu Ding,Fengjuan Liu,Jin Yang,Yingying Fan,Lvjian Yu,Zenghao Li,Na Jiang,Jing An,Ziwei Jiao,Cheng Wang
Penicillium expansum is the main causal organism of apple rot and causes huge economic losses during apple storage. Patulin (PAT) produced by P. expansum , occurs widely in apples and their products because of its water-solubility and thermal stability . In the present study, we isolated bacterial strains with antagonistic activity against P. expansum to effectively control the growth of P. expansum and production of PAT. We isolated a bacterium named YL-RY0310, which inhibited the growth of P. expansum and production of PAT in apples by 77.4% and 48.4%, respectively. Strain YL-RY0310 was 96% homologous to Bacillus mojavensis using morphological and 16S rRNA gene sequencing analyses. In addition, DNA amplification analysis using Bacillus -specific primers showed that the genes responsible for synthesis of lipopeptides of surfactin, iturins and fengycin are expressed. Oxford cup agar diffusion test showed that its crude lipopeptides could effectively inhibit the growth of P. expansum . Furthermore, strain YL-RY0310 could significantly degrade PAT; the degradation efficiencies of the intracellular and extracellular metabolites of the strain were 62.6% and 56.9%, respectively. Therefore, B. mojavensis YL-RY0310 could be used as a biocontrol agent to inhibit the growth of P. expansum and control PAT contamination in apples. This study provides a theoretical basis for a novel biological control strategy and degradation of mycotoxin.
研究领域:
植物病理学
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食品科学
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微生物学
✓ 已验证
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
Metals
·
2023
·Vol. 13
·期 4
·649
·
IF 2.9
Xiaoxi Ruan,Linlin Yang,Yan Wang,Yizhe Dong,Dake Xu,Mingxing Zhang
The corrosion of carbon steel causes dramatic economic losses each year. Since conventional corrosion prevention approaches may cause pollution problems to the environment, ecofriendly and effective corrosion approaches are desired. Microbiologically influenced corrosion inhibition (MICI) has been reported as a sustainable corrosion prevention method. This work aims to evaluate the corrosion inhibition effect of two bacterial strains,Tenacibaculum mesophilumD-6 andBacillussp. Y-6 by choosing Q235 carbon steel as a model system. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and a series of electrochemical techniques were applied to study the corrosion prevention effect. The electrochemical and pitting results indicated thatT. mesophilumD-6 displayed a better corrosion protection effect.T. mesophilumD-6 formed a denser and thicker biofilm on the Q235 surface thanBacillussp. Y-6. The maximum thickness of theT. mesophilumD-6 biofilms was 11.6 ± 0.7 μm, which is about twice as thick than that ofBacillussp. Y-6. The corrosion prevention mechanism was ascribed to the formation of biofilms as a barrier to block corrosive agents such as O2. This study provides a theoretical foundation for the application of biofilms as green and effective corrosion inhibitors for carbon steel.Keywords:Q235 carbon steel;Tenacibaculum mesophilumD-6;Bacillussp. Y-6;corrosion inhibition;biofilm formation ability
研究领域:
微生物学
·
材料科学
·
腐蚀工程
✓ 已验证
DOI
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
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2013
·Vol. 97
·期 21
·9525-9534
·
IF 3.689
Zhang Xiaoyun,Li Baoqing,Wang Ye,Guo Qinggang,Lu Xiuyun,Li Shezeng,Ma Ping
Bacillus atrophaeus CAB-1 displays a high inhibitory activity against various fungal pathogens and suppresses cucumber powdery mildew and tomato gray mold. We extracted and identified lipopeptides and secreted proteins and volatile compounds produced by strain CAB-1 to investigate the mechanisms involved in its biocontrol performance. In vitro assays indicated all three types of products contributed to the antagonistic activity against the fungal pathogen Botrytis cinerea . Each of these components also effectively prevented the occurrence of the cucumber powdery mildew caused by Sphaerotheca fuliginea under greenhouse conditions. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry revealed that the major bioactive lipopeptide was fengycin A (C15–C17). We isolated the crude-secreted proteins of CAB-1 and purified a fraction with antifungal activity. This protein sequence shared a high identity with a putative phage-related pre-neck appendage protein, which has not been reported as an antifungal factor. The volatile compounds produced by CAB-1 were complex, including a range of alcohols, phenols, amines, and alkane amides. O -anisaldehyde represented one of the most abundant volatiles with the highest inhibition on the mycelial growth of B. cinerea . To our knowledge, this is the first report on profiling three types of antifungal substances in Bacilli and demonstrating their contributions to plant disease control.
研究领域:
植物病理学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Long Wu,Xiaoyan Xiao,Kun Chen,Wenmin Yin,Qin Li,Pan Wang,Zhicheng Lu,Jing Ma,Heyou Han
Abstrcact Highly sensitive and selective detection of specific DNA sequences is of great importance in clinical diagnosis, environmental and food monitoring, but it still remains challenges to develop a facile method for real sample detection in aqueous solution. Here, a simple and recyclable surface enhanced Raman scattering (SERS) sensor was constructed for Bacillus thuringiensis (Bt) special gene fragment detection by Fe 3 O 4 magnetic beads (MBs) and Au–Ag core-shell nanorods (Au@Ag NRs). A hairpin DNA with sulfhydryl and biotin was attached to Au@Ag NRs as indicator, and MBs with streptavidin (SA) were acted as the capture probe. On the basis of the biotin–SA specific interaction, target sequences were first hybridized with the hairpin DNA and exposed the biotin. Subsequently, the Au@Ag NRs were captured by the streptavidin modified MBs, which reduced the suspended NRs and led to the change of Raman intensity . Under the optimal conditions, the SERS intensity revealed a good linearity with Bt transgene fragment ranging from 0.1 pM to 1 nM with a detection limit of 0.14 pM (S/N=3). To demonstrate the specificity of the strategy, the single-base mismatch in DNA was discussed in the SERS assay. The results showed that the sensitivity and accuracy of the proposed method was acceptable in DNA detection, revealing a great potential in special gene detection.
研究领域:
生物技术
·
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Lei Yu,Peng-tao Wang,Qing-tao Xu,Tao He,George Oduro,Yan Lu
In this study, magnetic humic acid (MHA) nanoparticle was prepared and confirmed the enhancement on reduction of azo dyes under high salt concentration. The anaerobic growth of the strain Bacillus sp. on quinones makes the biogenic hydroquinone feasible, and the latter was proven to reduce the azo dyes stoichiometrically. This in-situ reversibly oxidation and reduction of MHA acts as electron shuttle to catalyze the biotic reduction of the azo dyes. The biodegradation efficiencies in batch experiments and sequencing batch reactor with MHA were increased by 1.5–2.5 times as compared to that of control without the catalyzer. Moreover, the negligible leaching of HA under various environmental conditions suggests the robustness of the coating of HA on Fe/O surface. These results indicated that the as-prepared MHA could be used as redox mediator to accelerate the extracellular electron transfer, which is of great environmental significance for the removal of hazardous compounds.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Zhen Han,Qihua Lin,Shusheng Zhang,Xinru Zhou,Si Li,Faqian Sun,Chaofeng Shen,Xiaomei Su
Polychlorinated biphenyl (PCB)-degrading strains resuscitated by resuscitation promoting factor (Rpf) enlarged pure degraders to screen effective bio-inoculants for soil bioaugmentation . In this study, whole-genome analysis and PCB-degrading performance of a resuscitated strain LS1 were investigated. Importantly, the persistence and the physiological response of soil-inoculated LS1 were checked. The results indicate that the Bacillus sp. strain LS1 possessed the potential to degrade polycyclic aromatic compounds. LS1 exhibited better performance in degrading PCBs 18 and 52, but lower PCB 77 degradation capability. At PCBs concentration of 10 mg/L, the degradation efficiencies of PCBs 18, 52 and 77 within 96 h were 62.8 %, 59.6 % and 39.8 %, respectively. Combined the bph genes and metabolites detected, as well as the genes found in the genome, the abilities of LS1 for oxidative dehalogenation and mineralization of PCBs via HOPDA-benzoate-protocatechuate- β -ketoadipate pathway were determined. Notably, LS1 can still maintain survival and culturable state after inoculation into PCB-contaminated soil for 70 days. This is the first report to demonstrate the fate of resuscitated strain when used as soil bio-inoculant, which revealed the necessity and feasibility of using resuscitated strains to enhance bioremediation of PCB-contaminated soils.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2020
·
IF 5.778
Jing-qiu Hua,Rui Zhang,Rong-ping Chen,Guang-xiang Liu,Ke Yin,Lei Yu
A highly efficient bioflocculant, i . e ., Na-Bsp was successfully prepared by using a tolerant strain- Bacillus sp. under high-salt condition without sterilization. Salt-containing medium was not infected by other strains throughout the whole incubation period in 168 h. The as-prepared Na-Bsp was found to be cation-dependent, exhibiting high flocculant efficiency (FE) i.e., 97.69 ± 0.61%, towards kaolin particles by aid of Fe 3+ . High FE values were well maintained under a wide pH range and/or boiled water treatment , likely because of the main constituent of polysaccharide . The presence of hydroxyl, carboxyl, and amine groups on the bioflocculant surface were possibly responsible for strong interactions with heavy metals. The adsorption capacities of Pb 2+ , Cu 2+ and Cr 6+ were 1000.0, 434.8 and 384.6 mg g −1 , respectively. The changing of structure and configuration of bioflocculant during the metal adsorption were explored by the scanning electron microscope with electron energy loss spectroscopy and three-dimensional excitation-emission fluorescence spectrometry . This study provided a novel production method, whereby the conventional sterilization could be avoided, which is of great environmental significance for steam-saving. Furthermore, the as-prepared Na-Bsp exhibited high adsorption capacities toward heavy metals, which sheds lights on its potential usage as an alternative adsorbent.
研究领域:
环境生物学
·
微生物学
·
污染控制
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 53
·34208-34216
·
IF 4.036
Yilan Zhang,Xiaoguang Ying,Bo Liu,Bo Yang,Xiao Li
Nanofiber membranes have recently been considered as promising supports for the immobilization of microorganisms due to the simplicity and cost-effectiveness of electrostatic spinning technology and the ability to control fiber morphology, such as obtaining higher surface area and porosity. In this study, electrospun polyvinyl alcohol/sodium alginate/attapulgite (PVA/SA/ATP) nanofiber membrane was prepared as support for immobilized Bacillus cereus LY-1 for diesel degradation in an aqueous medium and a significant improvement in diesel removal efficiency was realized. The effect of modified ATP concentration on diesel removal was investigated. The results showed that the nanofiber membranes complexed with cetyl trimethyl ammonium bromide (CTAB) and 1% ATP (w/w) had the best capacity for diesel removing. When the initial diesel concentration was 2 g L−1, about 87.8% of diesel was removed by the immobilized LY-1 cells after 72 h. Immobilization of bacteria improves the ability of bacteria to survive in adverse environments. Immobilized LY-1 cells maintain the nature to remove diesel at high salinity or pH range of 6–9. Furthermore, the reusability of the LY-1 cells-immobilized PVA/SA/CTAB–ATP nanofiber membrane was tested. A diesel removal rate of 64.9% could be achieved after 4 times of use. PVA/SA/CTAB–ATP nanofibrous membranes with immobilized LY-1 cells are feasible, economical and environmentally friendly for remediation of diesel contamination in the aqueous medium, and have potential applications in the future.
研究领域:
环境科学
·
材料科学
·
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）