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关键词： Thermoalkaliphilic lipase   Thermophilic bacteria   Geobacillus stearothermophilus   Fish wastes   Lipase purification   Detergents industry  

摘要： This study was aimed to produce a high compatible thermoalkaliphilic lipase (TA) with detergents from new thermophilic bacterial strains utilizing fish wastes for industrial application. Among bacterial isolates, a new Geobacillus stearothermophilus FMR12 efficiently utilized fish wastes at a concentration of 20% (w/v), exhibiting highly lipolytic activity at extreme thermal and alkaline pH conditions. Optimized fermentation parameters of TA lipase production were ascertained, promoting the productivity of the TA lipase from 424 to 1038 U/ml. Purification results of TA lipase exposed prominent specific activity of 4788 U/mg, purification fold of 12.44, and 7.8% yield. The purified TA lipase demonstrated outstanding activity and stability in a temperature range of 40-95 degrees C and pH (4-11), revealing optimal activity at 70 degrees C and pH 9. The molecular weight of the enzyme was estimated to be 63 kDa. Compared to control, the TA lipase activity was promoted in the presence of calcium chloride. Likewise, Triton X-100 enhanced the activity of the TA lipase, recording 128% of the control enzyme. Interestingly, the TA lipase conserved higher than 90% of its activity after blending with commercial detergents, emphasizing its competence for detergent formulations. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Schizothorax zarudnyi   Nutritional nanotechnology   Growth performance   Hemato-immunology  

摘要： Iron and copper are two essential micronutrients that play important roles in vital biological processes, key enzymes and the immune system. In this study, the effects of diet supplementation with inorganic and nanoparticulate iron and copper on growth performance and hemato-immunological responses of snow trout Schizothorax zarudnyi (23.97 ? 0.45 g) were investigated for 84 days. The fish were fed by seven experimental diets supplemented with 0 mg copper and iron (Cu, Fe) (control), 150 mg inorganic iron (FeI), 3 mg inorganic copper (CuI), 150 mg FeI and 3 mg CuI (FeI + CuI), 150 mg nanoparticulate iron (FeNPs), 3 mg nanoparticulate copper (CuNPs), 150 mg FeNPs and 3 mg CuNPs (FeNPs+CuNPs) per kg of diet. The results showed that the diet supplementation with Fe and Cu improved the growth and feeding indices compared with the control treatment;however, the nanoparticulate Fe and Cu acted more effectively than their inorganic counterparts. The values pertaining to the most hematological parameters, such as RBCs, hematocrit and hemoglobin, were higher in nanoparticulate treatments than in the inorganic ones (P < 0.05). Serum total protein, albumin, globulin, cholesterol and triglyceride increased while glucose decreased with Fe and Cu supplementation to the diets, especially with the nanoparticulate form. The dietary addition of Fe and Cu, especially in nanoparticulate form, improved the levels of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), whereas it decreased the serum malondialdehyde (MDA) compared with the control treatment (P < 0.05). The activities of liver enzymes showed a decreasing trend in the fish fed with inorganic and nanoparticulate Fe and Cu compared with the control treatment. Lysozyme, complement component (C3) and alternative complement activity (ACH50) were improved in the fish fed with the diets supplemented by Fe and Cu, especially in the form of nanoparticulate, consequently increasi

关键词： prss59   1   Zebrafish   Trypsin   Peptidase   Recombinant protein   Renature  

摘要： Eleven genes, including prss59.1, were selected as candidate ovulation-inducing genes on the basis of microarray analysis and RNA sequencing in our previous study. To address the role of prss59.1, the prss59.1 gene knock-out zebrafish strain is currently being established by genome editing. In this study, for further phenotypic analysis of prss59.1, biochemical characterization of Prss59.1 was conducted using recombinant protein. A C-terminal histidine-tagged version of zebrafish Prss 59.1 was constructed. Although E. coli-pro-duced recombinant Prss59.1 showed almost no activity, peptidase activities appeared after denaturation and renaturation. Zebrafish Prss59.1 showed the highest activity against Lys-MCA. The optimal temperature and pH of the activity toward Lys-MCA were 37 degrees C and pH 8.0, respectively. The Km value was 0.17 mM. Thus, zebrafish Prss59.1 possesses the closed character of trypsin, as expected from the DNA sequence. (c) 2021 Published by Elsevier Inc.

关键词： Agaricus bisporus   Senescence   Low temperature storage   Cap browning   Melatonin  

摘要： Exogenous melatonin application at 0, 1, 10, 100, and 1000 mu M retarded cap browning of button mushrooms (Agaricus bisporus) by 78.35, 31.40, 30.91, 27.17, and 32.50 %, respectively. Mushrooms treated with 100 mu M melatonin also had lower weight loss and higher firmness. During the first 5 days of storage at 4 degrees C, higher H2O2 accumulation may serve as a signal for promoting endogenous melatonin accumulation by triggering the expression of TDC, T5H, SNAT, and ASMT genes, beneficial for preserving membrane integrity. Besides, the higher accumulation of phenols in mushrooms treated with 100 mu M melatonin may be ascribed to higher PAL and lower PPO gene expression and enzyme activity. Moreover, higher DPPH scavenging capacity in mushrooms treated with 100 mu M melatonin may be ascribed to the higher accumulation of phenols and ascorbic acid.

关键词： Solanum muricatum   Drought   Water stress   Photosynthetic pigments   Ions   Osmolytes   Antioxidant compounds  

摘要： The pepino (Solanum muricatum) is a neglected crop from the Andean region with potential for expansion to many areas of the world. However, there is a lack of studies in pepino related to its response to water stress. In this study, we have subjected plantlets of seven pepino cultivars (Mur1-Mur7) to three treatments consisting of a fully irrigated control (C), a moderate water stress (WS-M), and a severe water stress (WS-S). Thirty-one traits related to growth, photosynthetic pigments, mono and divalent ions, osmolytes and antioxidants were measured. Significant differences were found among cultivars for most traits. The WS-M treatment did not affect most growth and biochemical parameters, while large differences with respect to the control were observed with the WS-S treatment. In general, the WS-S treatment induced an inhibition of the growth parameters, mainly the reduction of the fresh weight of leaves, stems and roots, as well as their water content. A principal component analysis (PCA) performed on the relative values of growth traits, together with the ANOVA for the traits for which significant interaction cultivar x treatment was detected, showed that cultivars Mur2 and Mur4 are the most tolerant to water stress. Although no clear-cut differences were observed among cultivars, the waterstressed plants of Mur2 and Mur4 displayed less variation with respect to the control than the other cultivars for the physiological and biochemical traits measured. Overall, photosynthetic pigments, malondialdehyde and total flavonoids decreased under severe water stress, while proline, Na+ and K+ contents increased significantly. The results obtained provide relevant information on the response to drought of pepino and have allowed identifying two cultivars better adapted to water stress that could be useful in breeding pepino for drought tolerance.

关键词： Biological nitrogen and phosphorus removal   Iron-based materials   Mechanisms   Microbes   Low C/N ratio wastewater  

摘要： Wastewater with low carbon-to-nitrogen (low C/N) ratio has led to residues of nitrogen and phosphorus contaminants due to insufficient carbon source, which received increasing attention. Recently, iron-based materials have been widely used to enhance denitrification and considered to be one of the potential methods for efficient treatment of low C/N ratio wastewater. However, the substance cycles between iron, nitrogen and phosphorus are complicated, the reviews about iron-enhanced nitrogen and phosphorus removal performance needs to be further concluded. The objective of this review is to discuss the role of iron in nitrogen and phosphorus removal, and to provide theoretical support for improving effiencies of wastewater treatment to a certain extent. Firstly, the biological or biochemical processes of iron-mediated nitrogen and phosphorus removal were briefly summarized. The iron-mediated nitrogen removal efficiencies were significantly associated with some conditions affecting biological processes such as iron dosage, or the addition of electron shuttles. The removal pathways and iron dosage were the main factors related to N2O emission. In addition, iron had a great influence on phosphorus accumulating organisms (PAOs) which participated in phosphorus removal. On subsequently, the effects of iron on microbial activity, including promotion and inhibition, were revealed, with the pathways through which iron affected microbes way discussed simultaneously. Thirdly, the combination of iron with other materials was introduced, with the removal efficiencies of composite materials summarized. It was found that iron-based materials showed several advantages when combined with available materials such as activated carbon and metals. Finally, as the challenges for the processes of iron-enhanced nitrogen and phosphorus removal were still present, some suggestions for future research were proposed in this paper. Overall, this review suggests that iron-based materials play a