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Lipase production by Candida rugosa was carried out in submerged fermentation. Plackett-Burman statistical experimental design was applied to evaluate the fermentation medium components. The effect of twelve medium components was studied in sixteen experimental trials. Glucose, olive oil, peptone and FeCl3?6H2O were found to have more significance on lipase production by Candida rugosa. Maximum lipase activity of 3.8 u mL-1 was obtained at 50 h of fermentation period. The fermentation was carried out at optimized temperature of 30oC, initial pH of 6.8 and shaking speed of 120 r/min. Unstructured kinetic models were used to simulate the experimental data. Logistic model, Luedeking-Piret model and modified Luedeking-Piret model were found suitable to efficiently predict the cell mass, lipase production and glucose consumption respectively with high determination coefficient(R2). From the estimated values of the Luedeking-Piret kinetic model parameters, α and β, it was found that the lipase production by Candida rugosa is growth associated.  相似文献   
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Genetically modified (GM) cotton altered for insect and herbicide resistance released into commercial production in 1996 to 1997 now accounts for the lion's share of cotton acreage in the U.S. The rapid increase in transgenic cotton acreage in such a short period of time attests to the overall success of agricultural biotechnology. Grower satisfaction with transgenic cotton is largely due to several significant benefits, such as lower production costs, streamlined yet flexible management, and a reduced impact on the environment. This review article provides an overview of what has been accomplished thus far, as well as what improved germplasm may lurk on the horizon. A critical assessment of the gene delivery systems in cotton and possible targets for improvement is presented. The performance of the first generation of transgenic cotton plants engineered for insect, disease, or herbicide resistance is evaluated from the perspective of the benefits, the limitations that impact field performance, and management strategies. A few traits that hold future promise for increasing fiber productivity, enhancing and/or increasing the novelty of cotton-based products for the consumer, and improving human health and well-being are presented. Above all, cotton biotechnology offers to greatly enhance breeding programs by introducing novel traits that have eluded more traditional plant improvement methods and therefore will likely play an increasingly important role in the genetic improvement of cotton.  相似文献   
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International Journal of Peptide Research and Therapeutics - Marine ecosystems are unique and a largely diverse chest of natural resources which are still to be explored for new marine species....  相似文献   
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International Journal of Peptide Research and Therapeutics - Initial phase of COVID-19 infection is associated with the binding of viral spike protein S1 receptor binding domain (RBD) with the host...  相似文献   
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Polymorphisms in the human prion proteins lead to amino acid substitutions by the conversion of PrPC to PrPSc and amyloid formation, resulting in prion diseases such as familial Creutzfeldt–Jakob disease, Gerstmann–Straussler–Scheinker disease and fatal familial insomnia. Cation–π interaction is a non-covalent binding force that plays a significant role in protein stability. Here, we employ a novel approach by combining various in silico tools along with molecular dynamics simulation to provide structural and functional insight into the effect of mutation on the stability and activity of mutant prion proteins. We have investigated impressions of prevalent mutations including 1E1S, 1E1P, 1E1U, 1E1P, 1FKC and 2K1D on the human prion proteins and compared them with wild type. Structural analyses of the models were performed with the aid of molecular dynamics simulation methods. According to our results, frequently occurred mutations were observed in conserved sequences of human prion proteins and the most fluctuation values appear in the 2K1D mutant model at around helix 4 with residues ranging from 190 to 194. Our observations in this study could help to further understand the structural stability of prion proteins.  相似文献   
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