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21.
Anil K. Patel Jayesh J. Ahire Shrikant P. Pawar Bhushan L. Chaudhari Yogesh S. Shouche Sudhir Bhaskarrao Chincholkar 《Applied biochemistry and biotechnology》2010,160(1):140-155
Siderophoregenic Bacillus strain DET9 has been selectively isolated from dairy waste. It was evaluated for probiotic characteristics and susceptibility
pattern against antibiotics. Its spores showed excellent tolerance to simulated gastrointestinal tract conditions and exhibited
antimicrobial activity against organisms such as Escherichia coli, Micrococcus flavus, and Staphylococcus aureus. Its susceptibility to antibiotics reduces the prospect to donate resistance determinants if administered in the form of probiotic
preparations. It was observed to produce ∼60 mg/l catecholate type of siderophore under iron stressed conditions, identified
as a 2,3-dihydroxy benzoic acid by high-performance liquid chromatography, infrared spectroscopy, nuclear magnetic resonance,
and mass spectral analysis. Partial 16S-rRNA gene sequencing analysis shows that the isolate exhibited homology with Bacillus thuringiensis and Bacillus weihenstephanensis, whereas biochemical characterization revealed its novelty. DET9 exhibited no mortality of fishes in a 60-day trial, when
fishes (surfi tetra) were challenged up to 100 ppm cell concentration, with their daily diet. 相似文献
22.
Raghunath B. Toche Muddassar A. Kazi Shivaraj P. Patil Shrikant B. Kanawade Madhukar N. Jachak 《Journal of fluorescence》2010,20(5):1129-1137
Series of quinolone C3-substituted pyrazolines, isoxazolines, pyridines and pyrimidines were synthesized in good yields by the cyclocondensation
reactions of 1, 2-unsaturated ketones and hydrazines, hydroxylamine hydrochloride and dimedone respectively. The quinolone
derivatives (3, 5 and 7) were synthesized and further studied for their photophysical properties. High absorption and quantum
yield are found for N1-phenyl and C3,4-dimethoxy substituents on phenyl ring (3h). Energy optimization by PM6 methods showed high stability required for selection
of suitable candidates to be use as future blue emitters. 相似文献
23.
The after effects of β− -decay on time differential perturbed angular correlation (TDPAC) spectra of II–VI semiconductor CdS have been studied using
β− -emitting111Ag as well as111mCd as probe nuclei. The TDPAC spectrum of111Ag in CdS exhibits a time dependent interaction indicating that the preceding β− -decay leaves the daughter nucleus in an excited state. The recovery time (τg) of the probe atom was found to be 16±6 ns while Abragam and Pound's relaxation time (τkr) was found to be 9±2 ns. The results show that β− -decay does change the chemical environment around the probe atom. 相似文献
24.
25.
The concept of strong elements in posets is introduced. Several properties of
strong elements in different types of posets are studied. Strong posets are characterized in
terms of forbidden structures. It is shown that many of the classical results of lattice theory
can be extended to posets. In particular, we give several characterizations of strongness
for upper semimodular (USM) posets of finite length. We characterize modular pairs in
USM posets of finite length and we investigate the interrelationships between consistence,
strongness, and the property of being balanced in USM posets of finite length. In contrast
to the situation in upper semimodular lattices, we show that these three concepts do not
coincide in USM posets. 相似文献
26.
Soni A. Singh Shilpi Kabiraj Reena P. Khandare Shrikant P. Nalawade Kiran B. Upar 《合成通讯》2013,43(1):74-80
Amberlyst-15 (H+) resin catalyzes efficient cationic endo-cyclization of γ- and δ-unsaturated alcohols to yield tetrahydro-(2 H)-pyrans and oxepanes. The merits of the present protocol are good yield of the products under mild conditions, simple workup, and reusability of the resin. 相似文献
27.
Paola Rubiano-Buitrago Shrikant Pradhan Christian Paetz Hannah M. Rowland 《Molecules (Basel, Switzerland)》2023,28(1)
Cardiac glycosides are a large class of secondary metabolites found in plants. In the genus Asclepias, cardenolides in milkweed plants have an established role in plant–herbivore and predator–prey interactions, based on their ability to inhibit the membrane-bound Na+/K+-ATPase enzyme. Milkweed seeds are eaten by specialist lygaeid bugs, which are the most cardenolide-tolerant insects known. These insects likely impose natural selection for the repeated derivatisation of cardenolides. A first step in investigating this hypothesis is to conduct a phytochemical profiling of the cardenolides in the seeds. Here, we report the concentrations of 10 purified cardenolides from the seeds of Asclepias curassavica. We report the structures of new compounds: 3-O-β-allopyranosyl coroglaucigenin (1), 3-[4′-O-β-glucopyranosyl-β-allopyranosyl] coroglaucigenin (2), 3′-O-β-glucopyranosyl-15-β-hydroxycalotropin (3), and 3-O-β-glucopyranosyl-12-β-hydroxyl coroglaucigenin (4), as well as six previously reported cardenolides (5–10). We test the in vitro inhibition of these compounds on the sensitive porcine Na+/K+-ATPase. The least inhibitory compound was also the most abundant in the seeds—4′-O-β-glucopyranosyl frugoside (5). Gofruside (9) was the most inhibitory. We found no direct correlation between the number of glycosides/sugar moieties in a cardenolide and its inhibitory effect. Our results enhance the literature on cardenolide diversity and concentration among tissues eaten by insects and provide an opportunity to uncover potential evolutionary relationships between tissue-specific defense expression and insect adaptations in plant–herbivore interactions. 相似文献
28.
Prashant P. Raut Shrikant Y. Charde Pradeep Bishnoi 《Biomedical chromatography : BMC》2016,30(10):1696-1700
The aim of study was to develop a suitable analytical method for simultaneous estimation of levodopa, carbidopa and 3‐O‐methyl dopa in rat plasma. Chromatographic separation of plasma samples was achieved using a reverse‐phase C18 column. The mobile phase used consisted of a mixture of methanol and phosphate buffer (10 mM , pH 3.50) in the ratio of 90:10 v/v. All analytes were estimated by electrochemical detection at +800 mV. The developed method has been validated as per the standard guidelines. Precision study results were found to be satisfactory, with percentage relative standard deviation for repeatability and intermediate precision <3.96 and 6.56%, respectively, for all analytes detected in rat plasma. The developed method in rat plasma was found to be simple, rapid, accurate, precise and specific. The proposed method has been successfully applied for analysis of rat plasma samples obtained during an oral pharmacokinetic study of sustained release pellets of levodopa and carbidopa in rats. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
29.
The concept of `adjunct' operation of two lattices with respect to a pair of elements is introduced. A structure theorem namely,
`A finite lattice is dismantlable if and only if it is an adjunct of chains' is obtained. Further it is established that for
any adjunct representation of a dismantlable lattice the number of chains as well as the number of times a pair of elements
occurs remains the same. If a dismantlable lattice L has n elements and n+k edges then it is proved that the number of irreducible elements of L lies between n-2k-2 and n-2. These results are used to enumerate the class of lattices with exactly two reducible elements, the class of lattices with
n elements and upto n+1 edges, and their subclasses of distributive lattices and modular lattices.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
30.
Shrikant B. Kulkarni Richard M. Rodebaugh Norman H. Cromwell 《Journal of heterocyclic chemistry》1976,13(2):329-332
A number of 1-alkyl-2-carbomethoxyazetidines have been prepared from the reaction of primary amines with α,γ-dibromoearbonyl compounds. A series of base catalyzed reactions performed on selected cis, trans-1-alkyl-2-carbomethoxy-4-alkyl(aryl)azetidines reveal the cis isomer to be of greater thermodynamic stability. Furthermore, base catalyzed deuterium exchange studies suggest this to be the case. 相似文献