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Kothari, V.

Publications and source records attributed to Kothari, V..

3 recordsLinked to original sources

Sonic stimulation, and low power microwave radiation can modulate bacterial virulence towards Caenorhabditis elegans

Caenorhabditis elegans worms infected with different pathogenic bacteria were subjected to sonic treatment to investigate whether such sound treatment can exert any therapeutic effect on the infected worms. Sonic therapy corresponding to 400 Hz, and the divine sound om were found to confer protective effect on this nematode worm in face of bacterial infection, particularly that caused by Serratia marcescens or Staphylococcus aureus. The observed effect seemed to occur due to influence of sound on bacteria, and not on the worm. In addition to this, effect of microwave exposure on bacterial virulence was also investigated, wherein microwave exposure was found to reduce virulence of S. aureus towards C. elegans.

microbiology

Anti-infective potential of a quorum modulatory polyherbal extract (Panchvalkal) against certain pathogenic bacteria

Anti-infective potential of a polyherbal ayurvedic formulation namely panchvalkal was assayed against three pathogenic bacteria. This formulation was found to exert quorum-modulatory effect on Chromobacterium violaceum, Serratia marcescens, and Staphylococcus aureus at 250-750 g/mL. Besides altering production of the quorum sensing-regulated pigments in these bacteria, the test formulation also had in vitro effect on antibiotic susceptibility, catalase activity and hemolytic potential of the pathogens. In vivo assay confirmed the protective effect of this panchvalkal formulation on Caenorhabditis elegans, when challenged with the pathogenic bacteria. Repeated exposure of S. aureus to panchvalkal did not induce resistance in this bacterium. To the best of our awareness, this the first report on quorum-modulatory potential of panchvalkal formulation, validating the anti-infective potential and moderate prebiotic property of this polyherbal preparation.

microbiology

Frequency-dependent response of Chromobacterium violaceum to sonic stimulation, and altered gene expression associated with enhanced violacein production at 300 Hz

Chromobacterium violaceum was subjected to sonic (100-2000 Hz) stimulation, and the effect on its cell yield and quorum sensing regulated pigment (violacein) production was investigated. Sound corresponding to the 300 Hz was found to promote (by 1.52 fold) violacein production the most, with only marginal impact on cell yield. Whole transcriptome analysis revealed that a total of 342 genes (i.e. 4.63% of whole genome) were significantly up-regulated in the sonic stimulated culture. Enhanced violacein production in the sound stimulated culture seems to have stemmed from enhanced expression of the genes involved in glucose metabolism through pentose phosphate pathway, resulting in increased availability of erythrose-4-phosphate, to be used for synthesis of tryptophan, the precursor for violacein synthesis. Multiple ribosomal subunit genes, enzyme coding genes, and those associated with secretion/transport were up-regulated owing to sonic stimulation. This study is a good demonstration of the ability of sound waves to alter bacterial metabolism.

microbiology