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991.
Yaser Hassan Dewir Debasis Chakrabarty Eun Joo Hahn Subodh Kumar Datta Kee Yoeup Paek 《Plant Growth Regulation》2008,54(2):157-164
The present study reports on the kinetics of nutrient utilization during in vitro flowering of Spathiphyllum in air-lift bioreactor cultures. Levels of electrical conductivity (EC), anions and cations, pH, ethylene, sugar content
and photosynthetic enzymes were determined in bioreactor cultures of both flowering (FPs) and non-flowering (NFPs) plantlets
over a growth period of 12 weeks. A decrease in ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity with a
corresponding increase in phosphoenolpyruvate carboxylase (PEPcase) activity occurred during floral induction of Spathiphyllum in vitro. Sucrose concentration decreased significantly in FPs, while no changes in glucose, fructose and total sugars were
observed in both FPs and NFPs up to 8 weeks of culture. There were significant variations in mineral nutrient utilization
between FP and NFP cultures. These results provide an insight to the physiological processes involved in inflorescence formation
in Spathiphyllum. 相似文献
992.
993.
Abraham EC Huaqian J Aziz A Kumarasamy A Datta P 《Molecular and cellular biochemistry》2008,310(1-2):235-239
Earlier studies have shown significant loss of chaperone activity in α-crystallin from diabetic lenses. In vitro glycation
studies have suggested that glycation of α-crystallin could be the major cause of chaperone activity loss. The following lysine
(K) residues in α-crystallin have been identified as the major glycation sites: K11, K78, and K166 in αA-crystallin and K90,
K92, and K166 in αB-crystallin. The present study was aimed to assess the contribution of each of the above glycation site
in the overall glycation and loss of chaperone activity by mutating them to threonine followed by in vitro glycation with
fructose. Level of glycated protein (GP) was determined by phenylboronate affinity chromatography, advanced glycation end
products (AGEs) by direct ELISA using anti-AGE polyclonal antibody, and chaperone activity by using alcohol dehydrogenase
as the target protein. K11T, K78, and K166T mutants of αA showed 33, 17, and 27% decrease in GP and 32, 18, and 21% decrease
in AGEs, respectively, as compared to αA-wt. Likewise, K90T, K92T, K90T/K92T, and K166T mutants of αB showed 18, 21, 29, and
12% decrease in GP and 22, 24, 32, and 16% decrease in AGEs, respectively. Chaperone activity also showed concomitant increase
with decreasing glycation and AGEs formation. αA-K11T and αB-K90T/K92T mutants showed the largest decrease in glycation and
increase in chaperone activity. 相似文献
994.
995.
Gram-negative sepsis often produces endotoxin (LPS) which causes infection. Reduction in tissue perfusion due to microcirculatory failure may lead to septic shock. We studied the effect of LPS on lipid peroxidation of erythrocyte. In vitro studies using 50 microg to 250 microg LPS/ml blood showed increased lipid peroxidation of erythrocyte in a dose-dependent manner. The increased effect of lipid peroxidation does not occur with LPS when erythrocytes were washed to remove plasma and leukocytes. Mannitol and glycerol, known scavengers of hydroxyl radical, arrest the elevation in lipid peroxidation of erythrocytes after LPS treatment. Hemolysis of erythrocytes was reduced with low doses of LPS. Plasma lipid peroxidation was elevated after treatment of blood with LPS. From the results we suggest that the peroxidation of erythrocyte lipid caused by LPS may probably play a role in the production of septic shock. 相似文献
996.
An integrated process of textile dye removal and hydrogen evolution using cyanobacterium,Phormidium valderianum 总被引:2,自引:0,他引:2
Shah Vishal Garg Nikki Madamwar Datta 《World journal of microbiology & biotechnology》2001,17(5):499-504
The work deals with the removal of textile dyes from wastewater using cyanobacteria and integrating the dye removal ability of the organism with the ability to produce hydrogen. Phormidium valderianum, a marine cyanobacterium, has been shown to remove more than 90% of textile dyes Acid red, Acid red 119 and Direct black 155 from the solutions in the pH range higher than 11. Presence of phenolic compounds and metal chelators drastically reduced the dye adsorption capacity of the organisms. The mechanism involved in the dye adsorption has been investigated. Hydrogen production by cells grown in presence of dyes in any phase of their growth was found to be less in comparison to that of control (grown without dye). A laboratory scale reactor was designed to integrate the hydrogen production and dye removal ability of P. valderianum. 相似文献
997.
998.
999.
We describe the rational design, synthesis and development of a sterilizable biomimetic ligand for the affinity purification of glycoproteins. Based on mimicking the principles of natural carbohydrate recognition, a putative library of 196 glycoprotein-binding synthetic ligands was designed and synthesized on a polymeric support. Ligand 11/11, based on a triazine scaffold and immobilized on a hydrophilic support, was identified as the "lead" ligand. The carbohydrate recognizing the potential of the "lead" ligand was revealed by reduced binding of a periodate oxidized model glycoprotein, and by "sharp" elution profiles achieved with borate buffer eluents. Specific elution and competitive binding experiments determined the monosaccharide specificity of 11/11 in the order mannoside > glucoside > galactoside. The diastereo-selective performance of ligand 11/11 was quantified and reaffirmed by analytical affinity chromatography and (1)H-NMR, in the order galactoside < glucoside < mannoside with binding affinities (K(a), M(-1)) in the 63-214 and 20-83 M(-1) range, respectively. Partition coefficient analysis revealed binding constants towards glycoproteins in the 10(4) M(-1) range, that compared favourably with the affinities of carbohydrate binding lectins for glycoproteins, such as concanavalin A. Molecular modelling studies of ligand 11/11 revealed the formation of a pre-organized apolar "tweezer-like" cavity, containing complementary nitrogenous hydrogen bond donor and acceptor groups that formed selective interactions with the equatorial 3- and 4-hydroxyl groups of saccharides. 相似文献
1000.
Chakrabarty M Datta GK Ghosh S Debnath PK 《Indian journal of experimental biology》2001,39(5):485-486
The herb Desmotrichum fimbriatum Bl. (family: Orchidaceae), sold as Jibanti in West Bengal, is used in 'Rasayana therapy' in Ayurveda. Its effect on the modulation of the two antioxidant enzymes peroxidase and catalase has been studied in mice liver during 'cold water swim' (CWS) stress using appropriate controls. The drug, i.e. the aqueous ethanolic extract of the herb (whole plant) was found to increase peroxidase titre in the hepatic cells of normal mice. But in the stressed group, the drug displayed no effect on the peroxidase content, while it elicited an elevation of the catalase content. infinity-Tocoferol was used as the standard drug. These data suggested that the drug can ameliorate the peroxidative damage caused in mice by CWS stress. 相似文献