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排序方式: 共有803条查询结果,搜索用时 15 毫秒
1.
Pratima Bajpai Anshula Sharma N. Raghuram Pramod K. Bajpai 《Biotechnology letters》1988,10(3):217-220
Summary Ethanol concentration and fermentation productivities were substantially increased when soya extract was added to the fermentation medium using immobilized cells of a locally isolated strain of S. cerevisiae. Very high concentrations, 152 and 162 g/l of ethanol, were obtained from a medium containing 300 and 350 g/l sugars respectively by supplementing the medium with soya extract. The fermentation time was also reduced by more than 50%. 相似文献
2.
The effects of temperature and inlet pH of the medium on the ethanol productivity and activity of the immobilized Z. mobilis cells during continuous fermentation of glucose have been studied at various temperatures and pH. On changing the temperature from one steady state level to a new one, 6-8 h were required in order to fully experience the effect of a change in temperature; whereas 8-20 h were required on changing the pH. The optimum temperature of 37 degrees C and a broad pH range of 4.4-6.0 were observed for maximum ethanol productivity and ethanol yield. 相似文献
3.
Cryptic urokinase binding sites on human foreskin fibroblasts 总被引:13,自引:0,他引:13
Human foreskin cells possess sites on their surfaces that specifically bind both active and diisopropylphosphofluoridate-inactivated 2 chain 54 K Da [125I]-urokinase, but do not bind the 54 K Da single chain form of urokinase. 125I-urokinase bound to these sites is not internalized and is very slow to dissociate. There are about 40,000 available binding sites per cell. Brief incubation with pH 2.5 buffer at 5 degrees C unmasks another two to six fold more sites and also extracts plasminogen activator that, based on its accessibility to trypsin, appears to be at the cell surface. This suggests that the cryptic urokinase binding sites could be sites occupied with endogenous plasminogen activator. 相似文献
4.
To improve the inulinase (2,1-β-d-fructan fructanohydrolase, EC 3.2.1.7) stability of calcium alginate-immobilized Kluyveromyces marxianus cells, treatment with hardening agents has been investigated. Treatment of immobilized cells with some polycationic polymers resulted in little decrease in volumetric reactor productivity, but was most effective in increasing the inulinase stability of the immobilized cells. Inulinase stability of glutaraldehyde-hardened immobilized cells increased two-fold, and for hexamethylenediamine + glutaraldehyde and polyethyleneimine + glutaraldehyde-hardened cells increased six-fold compared with that of the unhardened cells. 相似文献
5.
Macdonald DG Bakhshi NN Mathews JF Roychowdhury A Bajpai P Moo-Young M 《Biotechnology and bioengineering》1983,25(8):2067-2076
Alkali treatment of corn stover improves the avaliability of cellulose and hemicellulose for enzymatic attack. Treatments were carried out for 1 to 60 min at temperatures and NaOH concentrations ranging from 100 to 150 degrees C and 0 to 2%, respectively. Solubilization of the stover and sugar production by enzymatic hydrolysis (Trichoderma viride cellulase) of the solid residue and the dissolved solids were used to measure the effect of caustic treatment. At 150 degrees C and 2% NaOH concentration, 65% of the original stover was dissolved after 5 min and 52% saccharificatin (g sugar/g stover) of the residue and dissolved solids by enzymatic hydrolysis was achieved compared to 20% for untreated corn stover. 相似文献
6.
7.
Sally Badawi Feda E. Mohamed Divya Saro Varghese Bassam R. Ali 《Traffic (Copenhagen, Denmark)》2023,24(8):312-333
Endoplasmic reticulum-associated protein degradation (ERAD) is a stringent quality control mechanism through which misfolded, unassembled and some native proteins are targeted for degradation to maintain appropriate cellular and organelle homeostasis. Several in vitro and in vivo ERAD-related studies have provided mechanistic insights into ERAD pathway activation and its consequent events; however, a majority of these have investigated the effect of ERAD substrates and their consequent diseases affecting the degradation process. In this review, we present all reported human single-gene disorders caused by genetic variation in genes that encode ERAD components rather than their substrates. Additionally, after extensive literature survey, we present various genetically manipulated higher cellular and mammalian animal models that lack specific components involved in various stages of the ERAD pathway. 相似文献
8.
Summary
Zymomonas mobilis cells were immobilized into small 1 mm diameter beads of Ca-alginate in order to minimize mass transfer limitations and maximize immobilized cell activity. A combination of small bead size with a high cell concentration of 58 g dry wt. cell per lit. bead volume resulted in high ethanol productivities using a newly designed packed bed bioreactor system. Steady-state dilution rates ranging from 0.4 h-1 to 3.9 h-1 were run resulting in a maximum productivity of 102 g ethanol/l/h for an inlet substrate concentration of 100 g glu/l and 87% conversion. The bioreactor was run continuously at a fixed dilution rate for 384 h and short intermittent treatment of the beads with CaCl2 temporarily increased ethanol productivity to a maximum of 116 g ethanol/l/h. 相似文献
9.
10.
Ray Mohapatra Amrita Lakshmanan Divya Mahesh Ramatchandirane Suchiang Kitlangki Jeevaratnam Kadirvelu 《International journal of peptide research and therapeutics》2021,27(3):1783-1797
International Journal of Peptide Research and Therapeutics - Biofilm forming pathogens are among the major causes of hospital-acquired infections and are not much affected by antibiotic treatment.... 相似文献