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11.
Tarjan Kaliaperumal S. Kumar Sathyanarayana N. Gummadi Anju Chadha 《Journal of industrial microbiology & biotechnology》2010,37(2):159-165
Asymmetric reduction of ethyl-4-chloro-3-oxobutanoate to (S)-ethyl-4-chloro-3-hydroxybutanoate in aqueous medium by resting cells of Candida parapsilosis ATCC 7330 was optimized. The influence of culture parameters (inoculum size, inoculum age and biocatalyst harvest time) and reaction parameters (co-substrate, resting cell, pH and substrate concentrations) on the asymmetric reduction were studied. It was found that these parameters significantly influenced the rate of the asymmetric reduction. Under the optimum conditions, the final concentration of (S)-ethyl-4-chloro-3-hydroxybutanoate, enantiomeric excess and the isolated yield of (S)-ethyl-4-chloro-3-hydroxybutanoate were 1.38 M (230 g/l), >99 and 95%, respectively. The space time yield was 115 mmol/lh, which is significantly higher than other whole cell biocatalysts reported so far. 相似文献
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Phytochemical analysis of dried twigs of Marsdenia roylei (family Asclepiadaceae) has resulted in the isolation of a trisaccharide, maryal, and a diglycoside, rolinose. Their structures were determined as O-beta-D-oleandropyranosyl-(1-->4)-O-beta-D-digitoxopyranosyl++ +-(1-->4)-D- cymaral and ethyl O-beta-D-oleandropyranosyl-(1-->4)-O-3-O-methyl-6-deoxy-beta-D- allopyranoside, respectively, by chemical degradation and spectroscopic methods. 相似文献
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Vinod Kumar 《Chronobiology international》1986,3(3):165-170
Groups of photosensitive, unstimulated or stimulated, male blackheaded buntings were subjected to photoregimes of 15 hr of green light of three intensities and 9 hr of dark per day. In some groups green light was interrupted with 90 min of bright fluorescent light at different times in the subjective day. While gonads did not develop or regressed in some groups, birds in others behaved as if exposed to long daylengths. The results besides suggesting the involvement of endogenous circadian rhythm during initiation and maintenance of gonadal growth indicate that the reproductive rhythms are entrained and induced by environmental photoperiod. 相似文献
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This study was conducted to study the long-term impact of bioinoculants, Azotobacter chroococcum and arbuscular mycorrhizal fungi (AMF) on growth and biomass yield of Jatropha curcas grown in nursery and in field conditions. The experiment was set up in a randomized block design, and the following treatments was designed (T1 = control, T2 = Azotobacter, T3 = inoculation with AMF, and T4 = inoculation with Azotobacter + AMF). Data on various growth attributes (shoot height and shoot diameter) and biochemical parameters [leaf relative water content (LRWC), sugars, protein, and photosynthetic pigments] were recorded up to 6 months in the nursery and in the field (18 months). Results pertaining to morpho-physiological traits showed Azotobacter and AMF consortia increase shoot height, shoot diameter, LRWC, sugars, proteins, and photosynthetic pigments over control under nursery conditions. Besides enhancing the plant growth, these bioinoculants helped in better establishment of Jatropha plants under field conditions. A significant improvement in the shoot height, shoot diameter, fruit yield/plant, and seed yield (g)/plant was evident in 18-month-old Jatropha plants under field conditions when Azotobacter and AMF were co-inoculated. This work supports the application of bioinoculants for establishment of Jatropha curcas in semi-arid regions. 相似文献
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Mukul C. Datta 《Prostaglandins & other lipid mediators》1985,29(4):561-577
The effects of prostaglandin E2 (PGE2) in association with erythropoietin on the synthesis of fetal and adult hemoglobin in peripheral blood-derived erythroid burst colonies from normal adults and from patients with sickle cell anemia were investigated. The synthesized hemoglobin at the end of 8, 14 or 18 days in culture was separated by DEAE-cellulose chromatography of 35S-methione labelled hemoglobin. Quantitative estimation of the synthesized hemoglobin phenotypes, for the three indicated culture periods, showed preferential synthesis of Hb F in addition to an overall increase in hemoglobin synthesis in PGE2 treated colonies. Furthermore, the reactivation of fetal hemoglobin production by PGE2 was more pronounced when the adherent cells were included in the culture dishes. These results indicate that the addition of PGE2 to culture dishes presumably constitutes an environmental change to promote the functional seen in the blood erythroid bursts in terms of Hb synthesis and switching. 相似文献