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831.
Rani Gupta Rinky Rajput Richa Sharma Namita Gupta 《Applied microbiology and biotechnology》2013,97(23):9931-9940
Keratinases are well-recognized enzymes with the unique ability to attack highly cross-linked, recalcitrant structural proteins such as keratin. Their potential in environmental clean-up of huge amount of feather waste has been well established since long. Today, they have gained importance in various other biotechnological and pharmaceutical applications. However, commercial availability of keratinases is still limited. Hence, to attract entrepreneurs, investors and enzyme industries it is utmost important to explicitly present the market potential of keratinases through detailed account of its application sectors. Here, the application areas have been divided into three parts: the first one is dealing with the area of exclusive applications, the second emphasizes protease dominated sectors where keratinases would prove better substitutes, and the third deals with upcoming newer areas which still await practical documentation. An account of benefits of keratinase usage, existing market size, and available commercial sources and products has also been presented. 相似文献
832.
833.
Using a rapid, quantitative high pressure liquid chromatographic (HPLC) procedure for the separation of S-adenosyl-L-homocysteine (AdoHcy) and its purinic metabolites in rat and mouse brain, kidney and liver, we found that uric acid is the principal catabolic product of AdoHcy metabolism in the liver, but that none forms in brain. Rat kidney formed about 10 times as much uric acid and half as much hypoxanthine as did mouse kidney. The HPLC procedure has been adapted to assay AdoHcy hydrolase activity which was found to be lowest in the brain and highest in the liver. 相似文献
834.
S. Suresh Kumar Lalit Kumar Vikram Sahai Rani Gupta 《Journal of industrial microbiology & biotechnology》2009,36(3):427-432
An alkaline lipase from Trichosporon asahii MSR 54 was used to develop presoak formulation for removing oil stains at ambient temperature. The lipase was produced in
a reactor followed by concentration by ultrafiltration and then it was dried with starch. The biochemical characteristics
of enzyme showed that it was an alkaline lipase having pH activity in the range of pH 8.0–10.0 and temperature in the range
of 25–50°C. The present lipase was active >80% at 25°C. The lipase was cystein activated with fourfold enhancement in presence
of 5 mM cystein and likewise the activity was also stimulated in presence of papain hydrolysate which served as source of
cystein. The presoak formulation consisted of two components A and B, component A was enzyme additive and B was a mixture
of carbonate/bicarbonate source of alkali and papain hydrolysate as source of cystein. The results indicated that the presoaking
in enzyme formulation followed by detergent washing was a better strategy for stain removal than direct washing with detergent
in presence of lipase. Further, it was observed that 0.25% presoak component B in presence of 100 U enzyme component A (0.1 g)
was the best formulation in removing maximum stain from mustard oil/triolein soiled clothes as indicated by increase in reflectance
which was found equal to that of control cloth. The lipase action in presoaked formulation was clearly indicated by quantitated
fatty acid release and also the TLC results of wash water, where oil hydrolytic products were visible only in presence of
enzyme in the treatment. The wash performance carried at 25°C indicated that washing at 25°C was at par with that at 40°C
as indicated by similar reflectance of the washed cloth piece though qualitative fatty acid release was higher at 40°C. 相似文献
835.
Ankati Sravani Rani T. Swaroopa Podile Appa Rao 《Journal of Plant Growth Regulation》2019,38(2):523-538
Journal of Plant Growth Regulation - Selection and application of rhizobacteria, for improved plant health will benefit from a complete understanding of the plant–bacteria interaction. Root... 相似文献
836.
We present evidence from experiments on overwintering populations of two Palearctic-Indian latitudinal migratory birds, the
black-headed bunting (Emberiza melanocephala) and the red-headed bunting (E. bruniceps), that the bird’s clock in interaction with day length regulates seasonal rhythms of migration and reproduction such that
physiological conflict between them is reduced. Initiation and termination of the body mass and testicular cycles are separately
regulated photoperiodic events. For example, under stimulatory photoperiods the response curve of body mass does not overlap
with that of the testicular growth. A response-specific photoperiodism is adaptive, since gain in body mass, critical to spring
migration, precedes gonadal recrudescence. Finally, migration as indicated by the night-time migratory restlessness under
experimental situations (e.g., intense locomotion under caged condition-called Zugunruhe) appears to be regulated by a separate circadian oscillator. 相似文献
837.
Callus cultures were initiated from axillary leaves, axillary shoots, hypocotyls, and root segments on Murashige and Skoog
(MS) (1962) medium supplemented with 2,4-D (2 mg l−1) and KN (0.2 mg l−1). Shoots differentiated best from axillary shoot base callus on MS medium containing BA (2 mg l−1). Regenerated shoots rooted best on MS medium containing IBA (2 mg l−1) alone, and IBA (2 mg l−1) with IAA (2 mg l−1). Plantlets were transferred to pots containing sand and soil mixture, acclimatized in a culture room and afterwards transferred
to the glasshouse.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
838.
This study reports the endemism and sexual system in the wet evergreen tree flora of the Western Ghats. A total of 656 species from 66 families and 231 genera were listed. This included a gymnosperm family (Podocarpaceae) and a monocot family (Arecaceae). No family was endemic to the Western Ghats, but 352 species (53%) from 43 families and five genera were endemic. Nearly 35% of the families had no endemics. The largest families with endemics were Dipterocarpaceae (92%), Anacardiaceae (84%), Lauraceae (72%), Fabaceae, Rubiaceae and Myrtaceae (68%). The top five contributing families in the tree flora of the Western Ghats were Euphorbiaceae, Lauraceae, Rubiaceae, Myrtaceae and Annonaceae. The 656 species were largely hermaphrodites (57%) followed by dioecious (20%), polygamous (16%) and monoecious species (5%). The rate of dioecy reported in this study (20%) is higher than reports for Puerto Rico (18%) but lower than the Malaysian rainforest (26%). Structurally, like the Neotropical forests, most evergreen forest types of the Western Ghats could be classified into four ensembles. Yet, the Western Ghats had fewer species than other tropical and Neotropical forests. The proportion of endemics in the ensembles of the Western Ghats ranged from 34% (ensemble IV) to 14% (ensemble I). 相似文献
839.
Daizy R. Batish Harminder Pal Singh Mansimran Kaur Ravinder Kumar Kohli Surender Singh Yadav 《Acta Physiologiae Plantarum》2008,30(3):401-405
Caffeine (1,3,7-trimethylxanthine), a purine alkaloid found naturally in over 100 plant species, has recently been viewed
as a safe chemical for management of pests including molluscs, slugs, snails, bacteria, and as a bird deterrent. It possesses
phytotoxicity against plant species, yet the mechanism of action is lacking. A study was conducted to determine the effect
of caffeine on the rooting of hypocotyl cuttings of mung bean (Phaseolus aureus) and the associated biochemical changes. At lower concentrations (<1,000 μM) of caffeine, though rooting potential was not
affected, yet there was a significant decrease in the number of roots and root length. At 1,000 μM caffeine, there was a 68%
decrease in the number of roots/primordia per cutting, whereas root length decreased by over 80%. However, no root formation
occurred at 2,000 μM caffeine. Further investigations into the biochemical processes linked to root formation revealed that
caffeine significantly affects protein content, activities of proteases, polyphenol oxidases (PPO) and total endogenous phenolic
(EP) content, in the mung bean hypocotyls. A decrease in rooting potential was associated with a drastic reduction in protein
content in the lower rooted portion, whereas the specific activity of proteases increased indicating that caffeine affects
the protein metabolism. Activity of PPO decreased in response to caffeine, whereas EP content increased significantly indicating
its non-utilization and thus less or no root formation. Respiratory ability of rooted tissue, as determined through TTC (2,3,5-triphenyl
tetrazolium chloride) reduction, was impaired in response to caffeine indicating an adverse effect on the energy metabolism.
The study concludes that caffeine interferes with the root development by impairing protein metabolism, affecting activity
of PPO (and thus lignification), and EP content, which are the crucial steps for root formation. 相似文献
840.
Srivastava Rajneesh Kumar Rajpoot Ritika Pandey Poonam Rani Anjana Dubey R. S. 《Journal of Plant Growth Regulation》2018,37(1):335-344
Journal of Plant Growth Regulation - In the present study, seedlings of indica rice (Oryza sativa L.) cultivars were subjected to 100 and 200 µM Cd(NO3)2 treatment in hydroponics for... 相似文献