FOOD MICROBIOLOGY
·
2024
·
IF 4.5
Qiaoyun Wei,Yuan Yuan,Jianhao Zhang,Jin Wang
This study investigated the fungicidal efficiency and mechanism of action of dielectric barrier discharge cold atmosphere plasma (DBD-CAP) in inactivating Aspergillus niger ( A. niger ) spores. The disinfection efficacy and quality of dried jujube used as the processing application object were also studied. The results indicated that the Weibull + Tail model performed better for spore inactivation curves at different voltages among various treatment times, and the spore cells were reduced by 4.05 log (cfu/mL) in spores suspension at 70 kV after 15 min of treatment. This disinfection impact was further supported by scanning electron microscope (SEM) and transmission electron microscopy (TEM) images, which showed that the integrity of the cell membrane was damaged, and the intracellular content leaked out after DBD-CAP treatment. Elevated levels of reactive oxygen species (ROS) during the treatment increased the relative conductivity of cells, and leakage of nucleic acids and proteins further supported the disinfection impact. Additionally, the growth and toxicity of surviving A. niger spores after treatment were also greatly reduced. When DBD-CAP was applied to disinfecting dried jujube, the spore number exhibited a 2.67 log cfu/g reduction after treatment without significant damage observed onto the quality ( P > 0.05 ).
研究领域:
食品科学
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微生物学
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2021
·
IF 3.757
Yangyang Cai,Shuqi Xing,Qifeng Zhang,Ruonan Zhu,Kai Cheng,Cuiqin Li,Xuefeng Zeng,Laping He
The extracellular Aspergillus niger GZUF36 lipase (EXANL1) has broad applicability such as synthesis of functional lipids. The wild-type strain is unstable, and the culture time is long. Studies on the selectivity of substrates for EXANL1 are not available. Therefore, this study aimed to express, purify, characterize and analyze the substrate specificity of EAXNL1. The results showed that EXANL1 was stable in the presence of 40 % ( v/v ) dimethyl sulfoxide, glycerol, toluene, and n-hexane. The relative activity was 104 %, 88 %, 81 %, and 76 %. The residual enzyme activity of EXANL1 was more than 85 % in surfactants with a low concentration. EXANL1 exhibited a high conversion rate (79 %) for p -nitrophenyl palmitate. The molecular docking of p -nitrophenyl palmitate into the active site of EXANL1 indicated that the preference for this fatty acid chain length might be due to the formation of hydrogen bonds. The distance between the carbonyl carbon atom of p -nitrophenyl palmitate and the nucleophilic oxygen atom of serine 162 was 2.91 Å. Both experiments revealed that EXANL1 exhibited higher specificity for p -nitrophenyl palmitate. These results indicated that EXANL1 could be a promising tool in organic synthesis and detergent industry. The molecular docking provided a basis for the explanation on the substrate selectivity of EXANL1.
研究领域:
生物化学
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酶学
·
工业微生物学
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2015
·
IF 4.494
Hongsen Zhang,Jian Zhang,Jie Bao
This study reported a high titer gluconic acid fermentation using dry dilute acid pretreated corn stover (DDAP) hydrolysate without detoxification. The selected fermenting strain Aspergillus niger SIIM M276 was capable of inhibitor degradation thus no detoxification on pretreated corn stover was required. Parameters of gluconic acid fermentation in corn stover hydrolysate were optimized in flasks and in fermentors to achieve 76.67 g/L gluconic acid with overall yield of 94.91%. The sodium gluconate obtained from corn stover was used as additive for extending setting time of cement mortar and similar function was obtained with starch based sodium gluconate. This study provided the first high titer gluconic acid production from lignocellulosic feedstock with potential of industrial applications.
研究领域:
生物技术
·
发酵工程
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DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2021
·Vol. 193
·期 7
·2225-2244
·
IF 2.926
Wan Yin,Fan Haowei,Gao Lin,Li Ruyi,Xie Mingyong,Wu ChouFei,Chen Longyan,Fu Guiming
Tannase from Aspergillus niger NL112 was purified 5.1-fold with a yield of 50.44% via ultrafiltration, DEAE-Sepharose Fast Flow column chromatography, and Sephadex G-100 column chromatography. The molecular weight of the purified tannase was estimated as 45 kDa. The optimum temperature and pH for its activity were 45 °C and 5.0, respectively. The results of circular dichroism, FT-IR (Fourier transform infrared) spectroscopy, and fluorescence spectra indicated that high temperature could lead to the change of tannase secondary and tertiary structures. Tannase had a greater affinity for tannic acid at 40 °C with a K m value of 2.12 mM and the greatest efficiency hydrolysis ( K cat / K m ) at 45 °C. The rate of inactivation ( k ) increased with the increase of temperature and the half-life ( t 1/2 ) gradually decreased. It was found to be 1.0 of the temperature quotient ( Q 10 ) value for tannic acid hydrolysis by tannase. The thermodynamic parameters of the interaction system were calculated at various temperatures. The positive enthalpy ( ΔH ) values and decreasing ΔH values with the increase of temperature indicated that the hydrolysis of tannase was an endothermic process. Our results indicated that elevated temperature could change the tertiary structure of tannase and reduce its thermostability, which caused a gradual decrease of tannase activity with an increase in temperature.
研究领域:
生物化学
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微生物学
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DOI
PubMed
高影响因子
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
·
2022
·Vol. 109
·期 6
·1043-1050
·
IF 2.807
Qv Wenrui,Wang Xilin,Li Ningyun,Du Jingjing,Pu Gaozhong,Zhang Hongzhong
In this study, exposure experiments were conducted to assess the effects of polystyrene nanoparticles (PS) and amine-modified polystyrene nanoparticles (APS) at environmental concentrations (1, 10, and 100 µg L − 1 ) on two fungal species ( Geotrichum candidum and Aspergillus niger ), isolated from leaf litter in streams, concerning their growth and metabolic activity. Results showed that PS at 1 and 10 µg L − 1 have hormesis effects on G. candidum growth. Compared with G. candidum , A. niger had higher sensitivity to nanoplastic exposure. Besides, the peroxidase and cellobiohydrolase activities of A. niger were significantly inhibited by nanoplastics (except 1 µg L − 1 PS), which would weaken its metabolic activity in carbon cycling. These results provided a new thought on how the growth and functions of aquatic fungi cope with the stress induced by nanoplastics. Overall, the study provided evidence for the different responses of aquatic fungi to nanoplastics in streams.
研究领域:
环境科学
·
微生物学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2021
·
IF 7.514
Qi Chen,Mingyue Zhang,Mengxue Chen,Mengru Li,Haiwei Zhang,Pengpeng Song,Tingting An,Pengxiang Yue,Xueling Gao
The three instant dark teas were produced from instant green tea (IGT) by liquid-state fermentations using the microorganisms Eurotium cristatum (EFT), Aspergillus niger (AFT), and sequential inoculation of E. cristatum / A. niger (EAFT), respectively. The volatile compounds of four tea samples were extracted by headspace-solid phase microextraction (HS-SPME) and analyzed using gas chromatography-mass spectrometry (GC-MS) coupled with chemometrics. A total of 97 volatile compounds were tentatively identified to distinguish three fermented instant dark from IGT. Alcohols, acids, esters, ketones, aldehydes, and heterocyclics could be clearly distinguished by principal component analysis (PCA), venn diagram, heatmap analysis and hierarchical cluster analysis (HCA). Descriptive sensory analysis revealed that AFT had a moldy, woody and herbal aroma; EFT showed woody and herbal aroma; and EAFT smelled an herbal, sweet, minty and floral aroma. This study indicates that fermentation using different microorganisms is critical in forming unique aroma characteristics of instant dark teas.
研究领域:
食品科学
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微生物学
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DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Jiepeng Chen,Yun Huang,Jiapin liu,Chengwei Li,He Zheng,Xi Xu,Lei Fu,Xing Li,Mingshan Wang,Yuanhua Lin,Haijun Cao
The sodium super ion conductor (NASICON) structure materials have attracted extensive attention because of its open three-dimensional crystal network framework and fast sodium ion migration rate. However, the poor electronic conductivity due to the presence of phosphate groups and the consequent high cost have been a barrier to commercialization. In this work, Na 4 MnV(PO 4 ) 3 (NMVP) with three-dimensional porous structure is synthesized in situ using Aspergillus niger as a biological template (noted as NMVP/ANDC). The cell wall of Aspergillus niger is rich in hydroxyl groups , which can adsorb metal ions well, so that NMVP particles can be synthesized on Aspergillus niger without stacking and agglomeration. NMVP grows along Aspergillus niger mycelium has a spongy-like three-dimensional porous network structure, which helps the contact between active materials and electrolyte, reduces the migration distance of sodium ions, and improves the conductivity of active materials. Therefore, NMVP/ANDC has good rate performance and cycle stability. It can provide 109 mAh g −1 at 0.5 C and 79.6% capacity retention after 3000 cycles at 5 C. The biological template method is proposed in this paper opens up a simple way for the preparation of other three-dimensional porous network structural materials.
研究领域:
材料科学
·
电化学
·
生物学
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Konglong Feng,Zaocheng Huang,Bo Peng,Weijie Dai,Yunqi Li,Xiaoai Zhu,Yunjiao Chen,Xing Tong,Yaqi Lan,Yong Cao
Deacidification of high-acid soy sauce residue (SSR) oil is crucial to utilization of SSR oil. Aspergillus niger lipase (ANL) has been widely applied for such purpose while its immobilization still has large room for improvement. ANL was immobilized onto six different macroporous acrylic resins, accounting the effect of the different textural properties of resins on stability and their potential for application in enzymatic deacidification. The resin MARE with lower porosity, higher bulk density, and medium hydrophobicity, was chosen as the best carrier for the best thermostability and reusability. ANL-MARE is a promising catalyst than Novozym 40086, which not only exhibited higher deacidification activity and good thermostability, but also was continuously reused for 15 cycles and efficiently catalyzed from high-acid SSR oil into diacylglycerol-enriched oil. Therefore, immobilized ANL was a novel, low-cost and recyclable biocatalyst that could be used as a good alternative to higher-cost commercial lipases in industrial applications.
研究领域:
生物化学
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食品科学
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产品关联
DOI
PubMed
高影响因子
CURRENT MICROBIOLOGY
·
2017
·Vol. 75
·期 5
·565-573
·
IF 1.322
Zhang Xin-guo,Liu Jin-wen,Tang Peng,Liu Zi-yu,Guo Guang-Jun,Sun Qiao-Yun,Yin Jian-jun
Adenosine deaminase (ADA) is an enzyme widely distributed from bacteria to humans. ADA is known as a potential therapeutic target for the treatment of lymphoproliferative disorders and cancer. Endophytes are endosymbionts, often bacteria or fungi, which live within plant tissues and internal organs or intercellular space. Endophytes have a broad variety of bioactive metabolites that are used for the identification of novel natural compounds. Here, 54 morphologically distinct endophyte strains were isolated from six plants such as Peganum harmala Linn., Rheum officinale Baill., Gentiana macrophylla Pall., Radix stephaniae tetrandrae, Myrrha , and Equisetum hyemale Linn. The isolated strains were used for the search of ADA inhibitors that resulted in the identification of the strain with the highest inhibition activity, Aspergillus niger sp. Four compounds were isolated from this strain using three-step chromatography procedure, and compound 2 was determined as the compound with the highest inhibition activity of ADA. Based on the results of 1 H and 13 C NMR spectroscopies, compound 2 was identified as 3-(4-nitrophenyl)-5-phenyl isoxazole. We showed that compound 2 was a new uncompetitive inhibitor of ADA with high cytotoxic effect on HepG2 and SMCC-7721 cells (the IC 50 values were 0.347 and 0.380 mM, respectively). These results suggest that endophyte strains serve as promising sources for the identification of ADA inhibitors, and compound 2 could be an effective drug in the cancer treatment.
研究领域:
药理学
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生物化学
·
肿瘤学
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DOI
PubMed
高影响因子
PREPARATIVE BIOCHEMISTRY & BIOTECHNOLOGY
·
2020
·
IF 1.415
Li Jun Li,Xiao Qing Liu,Xi Ping Du,Ling Wu,Ze Dong Jiang,Hui Ni,Qing Biao Li,Feng Chen
Isoquercitrin is a flavonoid with important applications in the pharmaceutical and nutraceutical industries. However, a low yield and high production cost hinders the industrial preparation of isoquercitrin. In the present study, isoquercitrin was prepared by biotransformation of rutin using α-L-rhamnosidase from Aspergillus niger JMU-TS528 combined with high-speed countercurrent chromatography (HSCCC) purification. As a result, the optimum transformation pH, temperature, and time were pH 4.0, 60 °C, and 60 min, respectively. The Km and Vmax were 0.36 mM and 0.460 mmol/min, respectively. For isoquercitrin production, the optimal rutin concentration and transformation time were approximately 1000 mg/L and 60 min. The rutin transformation rate reached 96.44%. The isoquercitrin was purified to a purity of 97.83% using one-step purification with HSCCC. The isoquercitrin was identified using UPLC-Q-TOF-MS. The comprehensive results indicated that the biotransformation procedure using the α-L-rhamnosidase from A. niger JMU-TS528 combined with HSCCC was a simple and effective process to prepare isoquercitrin, which might facilitate the production of isoquercitrin for industrial use.
研究领域:
生物化学
·
制药工程
·
食品科学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xudong Wang,Jiepeng Chen,Yun Huang,Jiapin Liu,Lei Fu,Li Liu,Wenping Zeng,Jie Xiao,Xiaoyan Zhang,Xing Li,Mingshan Wang,Yuanhua Lin,Haijun Cao
Na4MnV(PO4)3 (NMVP) has gained attention for its high redox potential, good cycling stability, and competitive price but suffers from poor intrinsic electronic conductivity and Jahn–Teller effect from Mn3+. In this work, cation/anion doping strategy was used for Aspergillus niger-bioderived carbon-coated NMVP (NMVP/AN) to improve the structural stability and electrochemical performance, where Al3+ doping inhibited the dissolution of Mn and enhanced the Mn3+/Mn2+ redox pair activity; besides, F– doping not only weakens the Na2–O bond but also endows the hierarchical and porous structure of NMVP/AN, which led to a more rapid and fluid transfer of Na+. The elaborately designed Na3.9Mn0.9Al0.1V(PO4)3/AN (NMAVP/AN) exhibits 105.9 mA h g–1 at 0.5 C, and the as-prepared Na3.1MnV(PO3.7F0.3)3/AN (NMVPF/AN) delivers 104.1 mA h g–1 at 5 C. Further demonstration of the hard carbon//NMAVP/AN full cell manifests the good potential of Al3+-doped NMVP/AN for practical applications (100.6 mA h g–1 at 1 C). These findings open up the possibility of unlocking the high-performance Na superionic conductor (NASICON).
研究领域:
材料科学
·
电化学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Caixia Li,Shuping Pu,Jiapin Liu,Yun Huang,Jiepeng Chen,Xinyan Xiang,Lei Fu,Chao Zou,Xing Li,Mingshan Wang,Yuanhua Lin,Haijun Cao
Sodium (Na) super ion conductor (NASICON) structure Na3MnTi(PO4)3 (NMTP) is considered a promising cathode for sodium-ion batteries due to its reversible three-electron reaction. However, the inferior electronic conductivity and sluggish reaction kinetics limit its practical applications. Herein, we successfully constructed a three-dimensional cross-linked porous architecture NMTP material (AsN@NMTP/C) by a natural microbe of Aspergillus niger (AsN), and the structure of different NMTP cathodes was optimized by adjusting different transition metal Mn/Ti ratios. Both approaches effectively altered the three-dimensional NMTP structure, not only improving electronic conductivity and controlling Na+ diffusion pathways but also enhancing the electrochemical kinetics of the material. The resultant AsN@NMTP/C-650, sintered at 650 °C, exhibits better electrochemical performance with higher reversible three-electron reactions corresponding to the voltage platforms of Ti4+/3+, Mn3+/2+, and Mn4+/3+ around 2.1, 3.6, and 4.1 V (vs Na+/Na), respectively. The capacity retention rate is up to 89.3% after 1000 cycles at a 2C rate. Moreover, a series of results confirms that the Na3.4Mn1.2Ti0.8(PO4)3 cathode has the most excellent electrochemical performance when the Mn/Ti ratio is 1.2/0.8, with a high capacity of 96.59 mAh g–1 and 97.1% capacity retention after 500 cycles.
研究领域:
材料科学
·
电化学
·
微生物学
✓ 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）