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121.
122.
Pongamia pinnata – a plant used since olden times in Ayurvedic treatment – is reported to have diverse functions including antibacterial, antidiabetic, antineurodegenerative, antiepileptic, antiulcer, etc. In this study, our objective was to prepare silver nanoparticles (AgNPs) by green synthesis mediated by methanolic seed extract of P. pinnata and to determine their antimicrobial and antioxidant potential and wound healing activity. AgNPs were characterized for particle size and shape and for antioxidant potential. Further, the AgNPs were incorporated in a gel. The wound healing activity was investigated using an excision wound healing model in Wistar rats. The AgNP‐loaded gel was applied topically to the wounded rats daily for 30 days. The wound contraction was calculated and histopathological studies of the healed tissues were conducted. Karanjin content of the extract was found to be 349 ± 2.16 mg g?1. Formation of AgNPs was confirmed using transmission and scanning electron microscopies and X‐ray diffraction. AgNPs showed good antioxidant potential and were active against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa. Significant wound healing activity (p < 0.05) was shown by the AgNP gel as compared to 5% Betadine ointment. Thus, the prepared AgNPs have antimicrobial and wound healing effects that may be useful in treatment of topical infections especially in wounds. 相似文献
123.
Avinash T. Shinde Sainath B. Zangade Shivaji B. Chavan Archana Y. Vibhute Yogesh S. Nalwar 《合成通讯》2013,43(23):3506-3513
This article describes simple and efficient method for the iodination of different aromatic amines, hydroxy aromatic aldehydes, hydroxy acetophenones and phenols using iodine and iodic acid in ethanol as a solvent. Notable advantages include mild reaction condition, no need of catalyst, short reaction time, simple practical procedure, giving excellent yield of the product. 相似文献
124.
Laxmi Kathawate Yogesh Shinde Ravi Yadav Sunita Salunke-Gawali 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1003-1011
The reactions of 3-chloro-2-hydroxy-1,4-naphthoquinone; chlorolawsone with “Na” metal (ClLw-1), CH3COONa (ClLw-2), NaOH (ClLw-3), KOH (ClLw-4) and K2CO3 (ClLw-5) have been studied. Dark brown solids obtained for ClLw-1 to ClLw-5 are characterized by elemental analysis FTIR, 1HNMR, UV–Visible spectroscopy, thermogravimetric analysis and DSC studies. FTIR of ClLw-1 to ClLw-5 shows decrease in νC=O frequency after complexation of alkali metal ions and νOH of adsorbed as well as coordinated water molecules have been observed between 3,600 and 3,100 cm?1. The benzenoid protons C(5)H and C(8)H shows down field shift due to intermolecular hydrogen bonding interaction with neighboring molecules and upfield shift have been observed for C(6)H and C(7)H protons in ClLw-1 to ClLw-5 in 1HNMR spectra. Bathochromic shift ~2 to ~5 nm have been observed for band at 287 nm. The nature of pyrolytic decomposition in chlorolawsone anion in ClLw-1 to ClLw-5 has been observed to be “gradual-1–abrupt–gradual-2”. Phase transition occurred during gradual-1 pyrolytic decomposition of chlorolawsone anion in ClLw-1 to ClLw-4 has been studied by DSC. 相似文献
125.
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
126.
Ashraf Y Rangrez Mohammad Y Abajy Walter Keller Yogesh Shouche Elisabeth Grohmann 《BMC biochemistry》2010,11(1):10
Background
Type four secretion systems (TFSS) are bacterial macromolecular transport systems responsible for transfer of various substrates such as proteins, DNA or protein-DNA complexes. TFSSs encode two or three ATPases generating energy for the secretion process. These enzymes exhibit highest sequence conservation among type four secretion components. 相似文献127.
The free energy of a quark-gluon plasma fireball in the hadronic medium is calculated in the Ramanathan et al statistical model after incorporating the effect of curvature. The result with the inclusion of curvature is found to produce
significant improvements in all the parameters we calculated with respect to the earlier results. The surface tension with
this curvature effect is found to be 0.17T
c3, which is two times the earlier value of surface tension which is 0.078T
c3, and this new result is nearly close to the lattice value 0.24T
c3. As far as transition is concerned, a thermodynamic variable like entropy shows weakly first-order phase transition and it
shows continuity in the behaviour of specific heat. 相似文献
128.
An efficient and operationally simple strategy for the synthesis of differently C-3 monosubstituted (9) and disubstituted (10) monocyclic β-lactams is described. This involves reaction of β-lactam carbocation equivalents (8) with an active aromatic, aliphatic and heterocyclic substrates in the presence of a Lewis acid. 相似文献
129.
Surendranath Y Kanan MW Nocera DG 《Journal of the American Chemical Society》2010,132(46):16501-16509
The mechanism of the oxygen evolution reaction (OER) by catalysts prepared by electrodepositions from Co(2+) solutions in phosphate electrolytes (Co-Pi) was studied at neutral pH by electrokinetic and (18)O isotope experiments. Low-potential electrodepositions enabled the controlled preparation of ultrathin Co-Pi catalyst films (<100 nm) that could be studied kinetically in the absence of mass transport and charge transport limitations to the OER. The Co-Pi catalysts exhibit a Tafel slope approximately equal to 2.3 × RT/F for the production of oxygen from water in neutral solutions. The electrochemical rate law exhibits an inverse first order dependence on proton activity and a zeroth order dependence on phosphate for [Pi] ≥ 0.03 M. In the absence of phosphate buffer, the Tafel slope is increased ~3-fold and the overall activity is greatly diminished. Together, these electrokinetic studies suggest a mechanism involving a rapid, one electron, one proton equilibrium between Co(III)-OH and Co(IV)-O in which a phosphate species is the proton acceptor, followed by a chemical turnover-limiting process involving oxygen-oxygen bond coupling. 相似文献
130.
Nairn AK Archibald SJ Bhalla R Gilbert BC Maclean EJ Teat SJ Walton PH 《Dalton transactions (Cambridge, England : 2003)》2006,(1):172-176
Reaction of Cu(BF(4))(2).6H(2)O with the N(3)O(2) donor ligand H(2)L (where H(2)L = N-benzyl-N',N'-di-tert-butyl-disalicyl-triaminocyclohexane) results in the formation of a novel Cu(II)L complex, 1. X-Ray crystallography of it shows the Cu(II) centre coordinated by two phenolate oxygens and two imine nitrogens in a distorted square plane with an elongated bond to the amine nitrogen (2.512 A) in the axial position. EPR spectroscopy gives g values of g(1) = 2.277, g(2) = 2.100, g(3) = 2.025, and A(1) = 15.6 mT which are consistent with the distorted square pyramidal coordination environment determined from the X-ray structure. UV/visible and electrochemical analysis of shows that it undergoes two reversible processes assigned to the successive oxidation of the phenolate oxygens to phenoxyl radicals, the first at E((1/2)) = 0.89 V (DeltaE = 81 mV, vs. Ag/AgCl) and the second at E((1/2)) = 1.13V (DeltaE = 84 mV, vs. Ag/AgCl). Chemical oxidation results in the formation of a species, assigned as [1](+)(.) which is EPR silent due to antiferromagnetic coupling between the Cu(II) centre and the bound phenoxyl radical. The oxidised species catalyses the oxidation of benzyl alcohol to benzaldehyde. 相似文献