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1.
DefattedMadhuca butyraceae seeds contain 24% of crude protein and 10.4% of saponins. The solubility ofMadhuca seed proteins was determined in water and NaCl as a function of pH and minimum solubility occurred at pH 4.0. The proteins
consist of three components with S20,w values of 2.2, 9.8 and 15.4. On gel filtration the proteins gave three peaks and on diethylaminoethyl cellulose chromatography
they resolved into two components. Thein vitro digestibility ofMadhuca seed protein was found to be 69% when assayed with a pepsin-pancreatin system. 相似文献
2.
Summary Two varieties of tomato (Pusa Rubi and Selection 120) positively responded to algal inoculation in terms of the yield of fruits and shoots, but there was no significant effect on the vitamin C content of the fruits. A combined application of urea and algae was more effective than the application of urea alone. 相似文献
3.
R Mathew J Verghese B V Venkataraman T Joseph 《Indian journal of experimental biology》1989,27(3):258-260
Acute exposure to insecticide (Baygon-spray; 5 ml/animal/5 min) inhalation in rats did not affect the learning process but produced a significant loss of memory (P less than 0.01 less than 0.001) whereas chronic exposure (one exposure per day for three weeks) produced a significant delay in learning (P less than 0.05) and memory (P less than 0.01). Acetylcholinesterase activity in brain after acute and chronic exposure declined significantly (P less than 0.01) during the learning process but returned to normal after 24 hr. 相似文献
4.
Adsorption of fungal spores on a synthetic polymer - High Density Polyethylene was successfully achieved using different pretreatments. Sonication of beads followed by ferric nitrate treatment or use of 0.1% tributyrin gave adsorption upto 46%. Use of dichloromethane as a solvent for sonication is recommended for its better performance in reuse studies (upto 5 times without much decrease in activity). 100 g of immobilized biocatabyst in a 7 L Fluidized Bed Bioreactor was found to perform better than shaker flask at a much lower power input. 相似文献
5.
Venkataraman Amarnath Traci L. Miller Arthur D. Broom 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1983,741(2):224-229
Poly(5-fluoro-2′-deoxyuridylic acid) was synthesized and its properties were compared with those of poly(dT) and poly(dU). It readily complexed with poly(dA). The 1:1 complex melted at about 20°C lower than poly(dA) · poly(dT). A triple-stranded helix, poly(dA)·2 poly(dF5U) was formed only in high salt (2.0 M NaCl). 相似文献
6.
The effects of radiation on the kinetics of Interleukin-2 (IL-2) production and utilization by mononuclear cells (MNCs) were studied. Mononuclear cells from normal, healthy individuals were subjected to various doses of radiation ranging from 0 to 2,000 rad and cultured in the presence of PHA. Supernatants from these cultures were harvested at various periods and their IL-2 contents determined by both the standard bioassay and ELISA. A radiation dose of 800 rad and higher had a marked effect on both IL-2 production and consumption. Although the supernatants from both the irradiated and non-irradiated MNCs contained maximal concentrations of IL-2 between 8 and 24 h of culture, the former had three times as much IL-2 as the latter. An increase in IL-2-mRNA levels was also noticed in irradiated, PHA-stimulated cells. Moreover, the supernatants from irradiated MNCs collected as late as 72 h after the initiation of culture contained more than 30% of the total IL-2 produced compared to less than 8% in supernatants from non-irradiated cells. Supernatants from non-irradiated cells incubated further with irradiated cells contained relatively higher quantities of IL-2 than those incubated continuously with non-irradiated cells. Supernatants from co-cultures of irradiated and non-irradiated MNCs contained less than expected amounts of IL-2 in two of the three subjects. Despite a difference in both the production and consumption of IL-2 between the irradiated and non-irradiated cells, there was no difference in their ability to generate IL-2 receptors. The results indicate that inactivation of radiosensitive suppressor T cells is associated with superinduction of IL-2 mRNA, increased production and decreased consumption of IL-2 by MNCs, thereby resulting in increased accumulation of IL-2. 相似文献
7.
H. N. Ravishankar Aparna V. S. Rao T. Ramasarma 《Molecular and cellular biochemistry》1996,154(2):101-106
Sequential addition of vanadyl sulfate to a phosphate-buffered solution of H2O2 released oxygen only after the second batch of vanadyl. Ethanol added to such reaction mixtures progressively decreased oxygen release and increased oxygen consumption during oxidation of vanadyl by H2O2. Inclusion of ethanol after any of the three batches of vanadyl resulted in varying amounts of oxygen consumption, a property also shared by other alcohols (methanol, propanol and octanol). On increasing the concentration of ethanol, vanadyl sulfate or H2O2, both oxygen consumption and acetaldehyde formation increased progressively. Formation of acetaldehyde decreased with increase in the ratio of vanadyl:H2O2 above 2:1 and was undetectable with ethanol at 0.1 mM. The reaction mixture which was acidic in the absence of phosphate buffer (pH 7.0), released oxygen immediately after the first addition of vanadyl and also in presence of ethanol soon after initial rapid consumption of oxygen, with no accompanying acetaldehyde formation. The results underscore the importance of some vanadium complexes formed during vanadyl oxidation in the accompanying oxygen-transfer reactions. 相似文献
8.
It has been suggested by some that the acquisition of symbolic capital in terms of honor, prestige, and power translates into an accumulation of material capital in terms of tangible belongings, and that on the basis of these goods high reproductive success may be achieved. However, data on completed fertility rates over more than one generation in so-called traditional societies have been rare. Ethnographic and demographic data presented here on the pastoral Bakkarwal of northern India largely corroborate the hypothesis concerning the interdependence between the attainment of various cultural goals and differential reproduction rates and indicate that the numbers of (especially male) surviving offspring and siblings are crucial to a man’s position in society. 相似文献
9.
G. Suvarnalatha L. Rajendran G. A. Ravishankar L. V. Venkataraman 《Biotechnology letters》1994,16(12):1275-1280
Summary A cell line of carrot (Daucus carota L) which produces anthocyanin was subjected to various elicitors and abiotic stresses: The elicitors tested were culture filtrates (CF) and cell extracts (CE) of certain bacteria and yeasts. The abiotic stresses were salts of certain metal ions. The production increase obtained with cell extracts of Bacillus cereus. Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus were 49, 72, 45 and 41% respectively over the control. Maximum elicitation was obtained with elicitor derived from cell extract of the yeast Rhodotorula rubra where it enhanced anthocyanin production by two fold. The abiotic stress agents Ca, Mn, Zn, Co, Fe & V enhanced anthocyanin production. Of all the metal ions tested Ca was the most effective. The elicitation process was governed by the type and level of elicitor. 相似文献
10.
Gopinath Chattopadhyay Shahbaz Ahmed Nonavinakere Seetharam Srilatha Aparna Asok Raghavan Varadarajan 《Protein science : a publication of the Protein Society》2023,32(1):e4514
Regulation of biological processes by proteins often involves the formation of transient, multimeric complexes whose characterization is mechanistically important but challenging. The bacterial toxin CcdB binds and poisons DNA Gyrase. The corresponding antitoxin CcdA extracts CcdB from its complex with Gyrase through the formation of a transient ternary complex, thus rejuvenating Gyrase. We describe a high throughput methodology called Ter-Seq to stabilize probable ternary complexes and measure associated kinetics using the CcdA-CcdB-GyrA14 ternary complex as a model system. The method involves screening a yeast surface display (YSD) saturation mutagenesis library of one partner (CcdB) for mutants that show enhanced ternary complex formation. We also isolated CcdB mutants that were either resistant or sensitive to rejuvenation, and used surface plasmon resonance (SPR) with purified proteins to validate the kinetics measured using the surface display. Positions, where CcdB mutations lead to slower rejuvenation rates, are largely involved in CcdA-binding, though there were several notable exceptions suggesting allostery. Mutations at these positions reduce the affinity towards CcdA, thereby slowing down the rejuvenation process. Mutations at GyrA14-interacting positions significantly enhanced rejuvenation rates, either due to reduced affinity or complete loss of CcdB binding to GyrA14. We examined the effect of different parameters (CcdA affinity, GyrA14 affinity, surface accessibilities, evolutionary conservation) on the rate of rejuvenation. Finally, we further validated the Ter-Seq results by monitoring the kinetics of ternary complex formation for individual CcdB mutants in solution by fluorescence resonance energy transfer (FRET) studies. 相似文献