ANTONIE VAN LEEUWENHOEK INTERNATIONAL JOURNAL OF GENERAL AND MOLECULAR MICROBIOLOGY
·
2020
·Vol. 113
·期 10
·1467-1477
·
IF 2.674
Yin Yi-Rui,Sang Peng,Yang Feng-Li,Li Tao,Yang Run-Feng,Liu Hong-Yan,Luo Zong-Long,Li Wen-Jun,Yang Li-Quan
A β-glucosidase gene ( bsbgl1a ) from Bacillus sp. CGMCC 1.16541 was expressed in Escherichia coli BL21 and subsequently characterized. The amino acid sequence shared 83.64% identity with β-glucosidase (WP_066390903.1) from Fictibacillus phosphorivorans . The recombinant β-glucosidase (BsBgl1A) had a molecular weight of 52.2 kDa and could hydrolyze cellobiose, cellotriose, cellotetrose, p-nitrophenyl-β- d -glucopyranoside ( p NPG), and p-nitrophenyl-β- d -xylopyranoside ( p NPX). Optimal activity for BsBgl1A was recorded at 45 °C with a pH between 5.6 and 7.6, and 100% of its activity was maintained after a 24 h incubation between pH 4 and 9. Kinetic characterization revealed an enzymatic turnover (Kcat) of 616 ± 2 s −1 (with cellobiose) and 3.5 ± 0.1 s −1 (with p-nitrophenyl-β- d -glucopyranoside). Interestingly, the recombinant enzyme showed cupric ion (Cu 2+ ), sodium dodecyl sulfate (SDS) and alcohol tolerance at 10 mM for Cu 2+ and 10% for both SDS and alcohol. Additionally, BsBgl1A had high tolerance for glucose (Ki = 2095 mM), which is an extremely desirable feature for industrial applications. Following the addition of BsBgl1A (0.05 mg/ml) to a commercial cellulase reaction system, glucose yields from sugarcane bagasse increased 100% after 1 day at 45 °C. This work identifies a Cu 2+ , SDS, alcohol, and glucose tolerant GH1 β-glucosidase with potential applications in the hydrolysis of cellulose for the bioenergy industry.
研究领域:
酶学
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微生物学
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生物技术
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Yiman He,Yuping Zhang,Fan Liang,Yuzhang Zhu,Jian Jin
Desalination of seawater, brackish water and urban sewage is an important way to solve the global water shortage. Polyamide (PA) membranes, including reverse osmosis (RO) membrane and nanofiltration (NF) membrane, are the primary technology for seawater desalination and clean water production. However, traditional thin-film composite PA (TFC-PA) membranes prepared from interfacial polymerization (IP) of amine monomers (either piperazine or m-phenylenediamine) in water and acyl chloride monomers in organic solvent are incapable of tolerating strong acid and chlorine environment. Here, we develop a new IP process, which takes place at the immiscible interface between dimethylacetamide (DMAc) and hexane (referred to as organic/organic IP), to prepare both chlorine-resistant and acid-resistant TFC-PA membranes. Compared to conventional water/oil IP process, the organic/organic IP process can adapt more kinds of amine monomers rather than just PIP, such as tetra (4-aminophenyl) methane (TMAP), tris (4-aminophenyl) amine (TAPA), and 4,4′,4''-(1,3,5-triazine-2,4,6-triyl) triphenylamine (TTA), which we studied in this work, thereby extending the PA molecular structure and enabling the membranes with greatly improved chemical stability. Among them, the TAPM-based TFC-PA membrane exhibits a NaCl rejection of 95.9% and no obvious NaCl rejection deterioration after soaking in a high concentration of NaClO (1000 ppm, pH 7) for more than 30 h, indicating excellent chlorine resistance. The TTA-based TFC-PA membrane shows a Na 2 SO 4 rejection of 97% and remains unchanged after being exposed to a wide pH scan of 2–12. The Organic/organic IP provides a new and easy-to-operate platform for designing chlorine and acid resistant TFC-PA membranes, which will greatly improve their environmental stability as the most advanced desalination membrane at present.
研究领域:
材料科学
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环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2021
·Vol. 105
·期 21
·8469-8479
·
IF 4.813
Meng Kang-Li,Lv Xin-Chen,Che Han-Yu,Li Yue,Chen Xian-Lin,Hu Meng-Xin,Yan Ming
Abstract Biofilms are heterogeneous structures composed of microorganisms and the surrounding extracellular polymeric substances (EPS) that protect the microbial cells from harsh environments. Saccharomyces boulardii is the first yeast classified as a probiotic strain with unique properties. However, tolerance of S. boulardii biofilms to harsh environments especially during production and in the gastrointestine remains unknown. In this study, S. boulardii cells were encapsulated in alginate microcapsules and subsequently cultured to form biofilms, and their survival and tolerance were evaluated. Microencapsulation provided S. boulardii a confined space that enhanced biofilm formation. The thick alginate shell and the mature biofilm improved the ability of S. boulardii to survive under harsh conditions. The exogenous encapsulation and the endogenous biofilm structure together enhanced the gastrointestinal tolerance and thermotolerance of S. boulardii. Besides, as the alginate shell became thinner with an increase in the subsequent culture duration, the EPS of S. boulardii biofilms exerted an important protective effect in resisting high temperatures. The encapsulated biofilm of S. boulardii after 24-h culture exhibited 60 × higher thermotolerance at 60 °C (10 min), while those after 6-h and 24-h culture showed 1000 × to 550,000 × higher thermotolerance at 120 °C (1 min) compared with the planktonic cells without encapsulation. The present study’s findings suggest that a combination of encapsulation and biofilm mode efficiently enhanced gastrointestinal tolerance and thermotolerance of S. boulardii. Key points
• Encapsulated S. boulardii in biofilm mode showed enhanced tolerance.
• Exogenous shell and endogenous biofilm provided dual protection to S. boulardii.
Graphical abstract
研究领域:
微生物学
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食品科学
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生物医药
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Qilin Yang,Shuangping Liu,Aibao Sun,Xin Li,Tiantian Liu,Xiao Han,Jian Mao
Amine oxidases have strong capabilities for the degradation of biogenic amines (BAs) in fermented foods. However, their application is limited by substrate specificity, and high concentrations of ethanol and salt can hinder their effectiveness. This study presents a novel approach utilizing comparative genomics, protein clustering analysis, and full homology modeling to identify three amine oxidases: KCYOBN from the salt-resistant Bacillus subtilis, and LYYOBN1 and LYYOBN2 from the ethanol-resistant Bacillus cereus. These enzymes are highly similar in structure and exhibit broad substrate specificities. KCYOBN maintains over 84% relative activity at 20% (w/v) NaCl, while LYYOBN1 and LYYOBN2 retain over 32 and 21% relative activity at 25% vol ethanol. Variations in key residues are one of the reasons for the differences in tolerance. In fermented foods, KCYOBN degraded 45.97% of the total BAs in cooking wine and 38.33% in fish sauce. LYYOBN1 achieved the highest degradation rate of 32.93% in huangjiu. LYYOBN2 exhibited degradation rates of 30.00% in soy sauce and 35.14% in wine with no significant impact on flavor compounds. The significance of this work lies in the identification of the novel salt-resistant KCYOBN and ethanol-resistant LYYOBN1 and LYYOBN2 through this new method, which can simultaneously degrade multiple BAs and have a broad application potential.
研究领域:
微生物学
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食品科学
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酶工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2019
·Vol. 26
·期 11
·1-10
·
IF 1.53
Zhao Tianhong,Zhang Yiwen,Peng Guofeng,Chen Yin
A branched hydrophobicity associated with polyacrylamide based on silica was synthesized successfully. The structure of the polymer was characterized by Fourier Transform Infrared Spectrometer (FT-IR), 1 H Nuclear Magnetic Resonance ( 1 H NMR) and Scanning Electron Microscopy (SEM). Several properties such as intrinsic viscosity, temperature resistance, salt tolerance, shear resistance and viscoelasticity of the polymer were evaluated. Experiment results had demonstrated that the introduction of vinyltriethoxysilane (VTS-SiO 2 ) and branching molecular structure could endow the polymer with excellent temperature tolerance capability, salt and shear resistant capability.
研究领域:
高分子化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2015
·
IF 3.082
Dongyang Xu,Qing Nie,Wenyan Wang,Lei Shi,He Yan
In this study, we characterized a bcrABC cassette and its genetic environment harbored by a plasmid in Listeria monocytogenes ( L . monocytogenes ) 11GZL18, a strain isolated from raw meat in 2011. The bcrABC cassette and its genetic environment were characterized, with a total of 33,727 nt nucleotide sequence obtained. The nucleotide sequences of the bcrABC cassette in strain 11GZL18 exhibited 100% identity to that on plasmid pLM80, which is harbored by L . monocytogenes strain H7550and H7858, and the neighboring 21,678 nt nucleotide sequence of bcrABC cassette showed 99% identity with plasmid pLM80. The plasmid curing experiment demonstrated the role of the plasmid in conferring benzalkonium chloride (BC) and cadmium (Cd) tolerance in this strain. The bcrABC cassette and cadAC genes from the L . monocytogenes 11GZL18 were harbored by plasmid, functional and transmissible, and led to the acquired tolerance in Gram-negative Escherichia coli ( E . coli ) DH5α by chemical and natural transformation. Besides, the efflux pump activity that is conferring tolerance to BC and Cd was observed in strain 11GZL18, while not in a plasmid-cured strain 11GZL18-C, confirming that efflux pumps play a role in plasmid-mediated tolerance to BC and Cd in L . monocytogenes 11GZL18. In this study we characterized the genetic organization of a novel BC and Cd tolerance determinants-harboring plasmid in a L . monocytogenes strain isolated from raw meat of animal origin, and demonstrated the potential horizontal transferability of this bcrABC cassette-harboring plasmid to E . coli . The findings will further improve our understanding of the adaptations of this organism to disinfectants such as BC and may contribute to elucidating possible dissemination of BC tolerance in foodborne L . monocytogenes .
研究领域:
微生物学
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食品安全
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Han Jia,Shaoyan Wang,Yingbiao Xu,Tingyi Wang,Lingyu Zhang,Jinyong Song,Xuehao Zhang,Lin Song,Haidong Jia,Hui Yan
Ionic liquids are regarded as the promising and efficient additives to use in various aspects of petroleum industry , especially in chemical EOR. In this investigation, three novel fatty acid ionic liquids (FAILs), methyltrioctylammonium octanoate ([N 8881 ][C 8:0 ]), methyltrioctylammonium laurate ([N 8881 ][C 12:0 ]) and methyltrioctylammonium palmitate ([N 8881 ][C 16:0 ]), were selected and evaluated for their performances in terms of surface/interfacial activity, temperature and salt resistances. The three FAILs could cause remarkable reduction of surface tension to ~30mN/m in their aqueous solutions, and the [N 8881 ][C 8:0 ] with the shortest anionic alkane chain exhibited the greatest surface activity among three FAILs. Then the size-match effect and intermolecular interaction were employed to explain the abnormal variations, which were confirmed by the control experiments using mixed surfactants and the molecular dynamics simulation . It was found that the binding energy in [N 8881 ][C 8:0 ] (−28.961 kcal/mol) was larger than that in [N 8881 ][C 16:0 ] (−22.942 kcal/mol), which should be responsible for their different surface activity. Moreover, the crude oil/water interfacial tension (IFT) could be decreased to the much level (4.9 ×10 −3 mN/m and 1.7 × 10 −2 mN/m) even at high-temperature conditions (80 °C) and at high-salinity conditions (100,000 mg/L), indicating the FAILs might be the ideal candidate for the EOR used surfactants with great temperature and salt tolerances. Meanwhile, the variations of IFT results further verified our proposed mechanism.
研究领域:
化学工程
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石油科学
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界面科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 3
·e56377
·
IF 2.7
Yaqi Ge,Pengfei Diao,Xiangxu Li,Yukun Zhou,Zhenchun Xu,Huiguang Bian,Yao Xiao,Chuansheng Wang
In this paper, pyrolysis carbon black (CBp) was introduced into nitrile butadiene rubber (NBR), the effects of the ratio of CBp and carbon black (N326) on the properties of NBR composites were investigated, and the optimal ratio was determined. On this basis, the accelerator DPG, coupling agent KH550 and CBp were modified by ball milling and plasma. The results showed that when the ratio of CBp to N326 was 40:15, the overall properties of NBR composites was better. Compared with the unmodified CBp/NBR composites, the change rate of tensile product, resilience and DIN abrasion of ball milling-plasma modified CBp/NBR composites in oil environment were reduced by 52.96%, 12.81%, and 27.19%, respectively, and the tear strength after double damage by high temperature and oil bath was increased by 15.63%, which resulted in better oil and high temperature-resistance. In summary, the ball milling-plasma combined with DPG/KH550 modified CBp can not only replace N326 carbon black, but also realize the preparation of NBR composites with better oil and high temperature-resistance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Zhichao Huang,Xiaoming Yuan,Zhenjun Zhu,Ying Feng,Na Li,Shubo Yu,Chun Li,Bo Chen,Shi Wu,Qihui Gu,Jumei Zhang,Juan Wang,Qingping Wu,Yu Ding
Bacillus cereus is a pathogenic bacterium that causes food contamination, resulting in food poisoning such as diarrhea and emesis. Therefore, it is crucial to develop effective strategies to control this bacterium. In this study, we isolated and characterized a novel B. cereus phage, named DZ1. Morphological and genomic analyses revealed that phage DZ1 is a new species belonging to the Andromedavirus genus. Phage DZ1 was tolerant to a wide range of pH values (5–9), temperatures (4–55 ℃), and high concentrations of NaCl solution (1000 mM). B. cereus with 21 different sequence types (STs) can be lysed by phage DZ1. Importantly, phage DZ1 inhibited B. cereus growth in spiked rice substrates or milk up to 36 and 72 h, respectively, with suppression of 3 log. Therefore, phage DZ1 is a useful biocontrol agent for the control of B. cereus in the food industry.
研究领域:
微生物学
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食品科学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Shuang Fu,Yingbo Chen,Xintong Wu,Liu Ye,Linzhe Xu,Xinyu Zhao
Nanofiltration (NF) membranes play a crucial role in wastewater treatment based on their unique separation mechanism. However, conventional polyamide nanofiltration membranes are susceptible to degradation in extreme pH or chlorine environments, resulting in a limited range of applications. In this study, hydrophilic functional coatings were constructed on polyethersulfone (PES) support using the biopolymer materials, κ-carrageenan (κ-CGN) and sodium carboxymethyl cellulose (CMC). The coatings were cross-linked with glutaraldehyde (GA) to form a dense three-dimensional network structure insoluble in water, enabling structural stability in harsh environments. The Na 2 SO 4 retention of the κ-CGN/CMC/PES composite membranes was maintained at 92.1 and 91.4 % after 38 days of immersion in 20 wt% H 2 SO 4 and 2 M NaOH aqueous solutions, respectively. Meanwhile, κ-CGN/CMC/PES maintained a good salt retention (Na 2 SO 4 , ∼90.0 %) after chlorine treatment (72,000 ppm h). The excellent separation performance of the κ-CGN/CMC/PES composite membranes at different pH and concentration of Cr (VI) indicated its wide application for Cr(VI) removal at harsh conditions.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Industrial Chemistry
·
2020
·Vol. 11
·期 2
·133-145
·
IF 0
Mpelwa Musa,Tang Shanfa,Jin Lijun
Mineral scale deposit is one of the major problems incessantly faced in the oil and gas producing wells and surface facilities, and if not well-handled can cause an unsuccessful petroleum production. To eradicate scale deposits, scale inhibitors (SIs) are commonly deployed into industrial water systems. Because of effectiveness and long squeeze lifetimes, organic phosphonate SIs are extensively used for preventing mineral scale formation in industrial water systems. However, they usually exhibit lower Ca 2+ and Mg 2+ tolerances that restrict their applications in harsh conditions where high inhibitory dosages are needed. In this paper, a multifunctional aminoalkylenephosphonate-based antiscalant having higher Ca 2+ and Mg 2+ tolerances is studied. The antiscalant was synthesized, characterized (FTIR and NMR spectroscopies), and evaluated in accordance with the NACE Standard Method (TM0374) for preventing CaSO 4 and CaCO 3 formation in the petroleum industry. The effects of inhibitory dosages, water hardness, temperature, incubation period, and pH were studied. We further tested the performance of the antiscalant in simulated field waters. Experimental results show that the multifunctional aminoalkylenephosphonate-based antiscalant has better inhibitory properties as compared to conventional aminoalkylenephosphonate-based SIs. The incorporation of the sulfonate group into the molecule significantly improved the solubility of the antiscalant and hence its tolerances to Ca 2+ and Mg 2+ ions. Also, it bolstered thermal stability of the inhibitor. The results from simulated field conditions are promising. The synthesized antiscalant performed superbly than the conventionally aminomethylenephosphonate antiscalants where Ca 2+ and Mg 2+ concentrations are challenging.
研究领域:
化学工程
·
石油工程
✓ 已验证
DOI
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Chunling Li,Zhikun Wang,Wendong Wang,Huafeng Zhu,Shuangqing Sun,Songqing Hu
Synergism has developed to be an important means to improve the foaming, stabilizing and responsive deforming characteristics of foam. Here, CO 2 /N 2 responsive surfactants with tunable lengths of carbon chains are synthesized. Through forming and deforming testing, the obtained 11-dimethylamino-undecyl sulfate sodium (11-DUSNa) with 11 carbons on the linear tail chain has the best comprehensive performance. 11-DUSNa is then mixed with Cocamidopropyl Hydroxyl Sulfobetaine (CHSB) to produce a compound foam with enhanced temperature and salt tolerance. Experimental observations show that the compound foam has the largest stability by adding 3.2 mol/L divalent salts (Ca 2+ , Mg 2+ ), and has improved temperature resistance from 20 to 100 °C compared to singular surfactant foam. The compound foam defoams in response to the injection of CO 2 within 2200 s. The foaming and defoaming processes can be cycled many times by repeat addition of NaOH for deprotonation and CO 2 for protonation of amino groups. Molecular dynamics simulations show that Ca 2+ and Mg 2+ cations distributing around the head groups of surfactants form a stable network liquid film wall, explaining why the compound foam is salt tolerant. The synergistic effect of CHSB and anions increases the liquid film wall thickness and therefore leads to better temperature resistance.
研究领域:
化学工程
·
材料科学
·
分子生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）