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981.
982.
Jay Shankar Singh Yadav Jyothi Bezawada Song Yan R. D. Tyagi R. Y. Surampalli 《Applied biochemistry and biotechnology》2014,172(6):3207-3222
Cheese whey is a by-product of cheese-manufacturing industries, and the utilization of whey is a challenging problem either to use it or dispose it, because only few microorganisms can metabolize the whey lactose. Enzymatic hydrolysis of whey lactose to glucose and galactose by β-galactosidase is the approach for biotechnological application. Kluyveromyces marxianus cells were permeabilized with non-toxic, biodegradable, anionic detergent N-lauroyl sarcosine (N-LS) for the enzyme activity. The permeabilization process parameters (N-LS concentration, solvent volume, temperature and incubation time) were optimized. The maximum β-galactosidase activity of 1,220 IU/g dry weight was obtained using permeabilized cells under optimized conditions. Moreover, viability of the permeabilized cells was also evaluated, which showed that cells were alive; however, viability was reduced by two log cycles. The permeabilized cells were evaluated for whey lactose hydrolysis. The maximum lactose hydrolysis of 91 % was observed with 600 mg (dry cell weight/100 mL) in whey powder (5 % w/v) solution at 180-min incubation, pH 6.5 and 30 °C. Further, the hydrolyzed whey was evaluated for amelioration of growth of non-lactose-consuming yeast Saccharomyces cerevisiae. S. cerevisiae was able to grow in hydrolyzed whey simultaneously with K. marxianus. The study confirmed that N-LS could be used to permeabilize K. marxianus cells to make available the enzyme activity. 相似文献
983.
A simple synthesis of (+)-hepialone, a sex pheromone of Hepialus californicus B is reported by employing a 1,3-dipolar cycloaddition as a key step. 相似文献
984.
Trimethylsilyl iodide (TMSI) was found to be an efficient catalyst for the vinylogous Mukaiyama aldol reaction of 2-(trimethylsilyloxy)furan with various aldehydes with good diastereoselection. The reaction proceeds rapidly in CH2Cl2 affording the corresponding 5-(hydroxy(aryl)methyl)furan-2(5H)-ones in good yields. This method offers significant advantages such as efficiency, generality, and mild reaction conditions with shorter reaction time.
985.
Oxidative coupling of thiols into disulfides using “Clayan” under microwave irradiation in described. The rapid reaction and dry medium are the important features of the reaction. 相似文献
986.
1,3-diols have been prepared from monosubstituted olefins, and the utility of this method in the synthesis of α-lipoic acid has been described. 相似文献
987.
Aldoximes undergo rapid dehydration with H2SO4/ SiO2 solid support, under microwave irradiation in dry media to afford nitriles in high yields. 相似文献
988.
Abstract A simple and efficient method for multicomponant synthesis of 3,4-dihydropyrimidinones has been reported. All the reactions were carried out using samarium triflate as catalyst (10 mol%) at acetonitrile reflux. This procedure is applicable to a variety of substrates such as aliphatic, aromatic, and heterocyclic aldehydes.
ACKNOWLEDGMENT
A. R. R. is thankful to the Council of Scientific and Industrial Research, New Delhi, for providing a fellowship. 相似文献989.
Jhillu S. Yadav Uttam Dash Nagesh Guguloth Debendra K. Mohapatra 《Helvetica chimica acta》2013,96(4):663-674
A linear synthesis of the major oxepane fragment of zoapatanol, showing the induction of uterine contractions, and cervical dilation and uterine bleeding (by the concentrated zoapatle tea) in early human pregnancy, isolated from the leaves of Mexican zoapatle plant Montanoa tomentosa, is described from known intermediate involving Sharpless asymmetric epoxidation, bis‐epoxide opening reaction with Corey? Chaykovsky reagent, ring‐closing metathesis reaction, and Horner? Wadsworth? Emmons olefination reaction as key steps. 相似文献
990.