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41.
A new series of complexes is synthesized by template condensation of oxalyldihydrazide and glyoxal in methanolic medium in the presence of trivalent chromium, manganese and iron salts forming complexes of the type: [M(C(8)H(8)N(8)O(4))X]X(2) where M = Cr(III), Mn(III), Fe(III) and X = Cl(-1), NO(-1)(3), CH(3)COO(-1). The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic susceptibility measurements, electronic, NMR, infrared and far infrared spectral studies. On the basis of these studies, a five coordinate square pyramidal geometry for these complexes has been proposed. The biological activities of the metal complexes were tested in vitro against a number of pathogenic bacteria and some of the complexes exhibited remarkable antibacterial activities. 相似文献
42.
Epoxide hydrolases (EHs; 3.3.2.x) catalyze the enantioselective ring opening of racemic epoxides to the corresponding enantiopure vicinal diols and remaining equivalent unreacted epoxides. These epoxides and diols are used for the synthesis of chiral drug intermediates. With an upsurge in the methods for identification of novel microbial EHs, a lot of EHs have been discovered and utilized for kinetic resolution of racemic epoxides. However, there is still a constraint on the account of limited EHs being successfully applied on the preparative scale for industrial biotransformations. This limitation has to be overcome before application of identified functional EHs on large scale. Many strategies such as optimizing reaction media, immobilizing EHs and laboratory-scale directed evolution of EHs have been adopted for enhancing the industrial potential of EHs. In this review, these approaches have been highlighted which can serve as a pathway for the enrichment of already identified EHs for their application on an industrial scale in future studies. 相似文献
43.
Influence of Isatin on rat tissue acid phosphatase has been studied. It has an organ-specific effect, the liver enzyme is activated, the brain enzyme is inhibited while those of kidney and intestine are not affected. Isatin activation of the liver enzyme is of mixed type and pH dependent. Rat liver enzyme appears to require intact amino and sulfhydryl groups for activity. Isatin seems to combine with the enzyme through the sulfhydryl group of the latter. 相似文献
44.
45.
In severe iodine deficient areas, iodine deficiency has been documented to be an important etiological factor leading to poor fetal growth and development. Iodine is essential for physical growth and development of the central nervous system of the fetus. Iodine deficiency in pregnant mothers leads to increased incidence of infertility and abortions, perinatal mortality and infant child mortality. The clinical iodine supplementation trials have documented adverse health consequences due to iodine deficiency. Evidence from observational studies concludes that prevention of iodine deficiency can lead to reduction in infant mortality rate and facilitate to achieve millennium development goal-4. 相似文献
46.
Rice is the most amenable crop plant for genetic manipulation amongst monocots due to its small genome size, enriched genetic map, availability of entire genome sequence, and relative ease of transformation. Improvement in agronomic traits of rice is bound to affect a sizeable population since it is a primary source of sustenance. Recent advances like use of ‘clean gene’ technology or matrix attachment regions would help improve rice transformation. Function of several novel genes and their promoters has been analyzed in transgenic rice. Significant progress has been made in introducing traits like herbicide, biotic stress and abiotic stress tolerance. Attempts also have been made to enhance nutritional characteristics of the grain and yield. Identification of genes controlling growth and development can be used to modify plant architecture and heading period. Transgenic rice can serve as a biofactory for the production of molecules of pharmaceutical and industrial utility. The drive to apply transgenic rice for public good as well as commercial gains has fueled research to an all time high. Successful field trials and biosafety of transgenic rice have been reported. This would act as a catalyst for greater acceptance of genetically modified food crops. The lessons learnt from rice can be extended to other cereals thereby opening new opportunities and possibilities. 相似文献
47.
Jitender Kumar Shanker K. Singh Rajneesh Sirohi Ajay Kumar Dang 《Biological Rhythm Research》2017,48(4):567-575
Earlier, we reported the impact of season on neutrophils’ functional competence and also hypothesized that it could be the impact of different seasons on neutrophils’ activation. In cerebration, the present study aimed to provide insights into neutrophils’ activation in terms of phosphorylation of tyrosine containing proteins during different seasons. Ten Hariana cows participated in the study and eight times blood samples were collected from each animal (twice in each month) during each season. Phosphorylation of tyrosine proteins was evaluated using western blotting and immunolocalization using a fluorescent microscope. Immuno blotting identified six tyrosine-phophorylated proteins p28, p42, p44, p58, p84, and p104 in winter and rainy seasons, whereas, p84 protein was absent in summer season. Immunolocalization revealed positive immune reactivity (IR) for tyrosine-phosphorylated proteins and significantly (p < 0.05) lower percent of neutrophils showed positive IR during the summer season as compared to winter and rainy seasons. The results of the study evidently indicate the activation of neutrophils is mediated through tyrosine phosphorylation and this may be a probable reason behind the decreased neutrophils’ functional competence during the summer. Further studies are warranted to decipher the possible association between tyrosine phosphorylation and expression of surface receptors required for the recruitment of neutrophils. 相似文献
48.
Sareen Sindhu Bhusal Nabin Kumar Manoj Bhati Pradeep Kumar Munjal Renu Kumari Jyoti Kumar Sundeep Sarial A. K. 《Journal of plant biochemistry and biotechnology.》2020,29(1):15-23
Journal of Plant Biochemistry and Biotechnology - Four hundred and ninety-six indigenous and exotic aestivum and durum wheat accessions were phenotyped for heat tolerance at three locations during... 相似文献
49.
This article presents two hybrid strategies for the modeling and optimization of the glucose to gluconic acid batch bioprocess. In the hybrid approaches, first a novel artificial intelligence formalism, namely, genetic programming (GP), is used to develop a process model solely from the historic process input-output data. In the next step, the input space of the GP-based model, representing process operating conditions, is optimized using two stochastic optimization (SO) formalisms, viz., genetic algorithms (GAs) and simultaneous perturbation stochastic approximation (SPSA). These SO formalisms possess certain unique advantages over the commonly used gradient-based optimization techniques. The principal advantage of the GP-GA and GP-SPSA hybrid techniques is that process modeling and optimization can be performed exclusively from the process input-output data without invoking the detailed knowledge of the process phenomenology. The GP-GA and GP-SPSA techniques have been employed for modeling and optimization of the glucose to gluconic acid bioprocess, and the optimized process operating conditions obtained thereby have been compared with those obtained using two other hybrid modeling-optimization paradigms integrating artificial neural networks (ANNs) and GA/SPSA formalisms. Finally, the overall optimized operating conditions given by the GP-GA method, when verified experimentally resulted in a significant improvement in the gluconic acid yield. The hybrid strategies presented here are generic in nature and can be employed for modeling and optimization of a wide variety of batch and continuous bioprocesses. 相似文献
50.
Ajit Rayamajhi Sam Nightingale Nisha Keshary Bhatta Rupa Singh Elizabeth Ledger Krishna Prasad Bista Penny Lewthwaite Chandeshwar Mahaseth Lance Turtle Jaimie Sue Robinson Sareen Elizabeth Galbraith Malgorzata Wnek Barbara Wilmot Johnson Brian Faragher Michael John Griffiths Tom Solomon 《PloS one》2015,10(4)