The compound paraquat dichloride hydrate significantly affects the in vitro growth rate of a Chromobacterium violaceum wild type strain

Abstract

The present study aimed to assess the <em>in vitro</em> growth rate of the <em>C. violaceum</em> wild type strain ATCC12472 when exposed to the compound paraquat dichloride hydrate, one of the most herbicides largely employed in agriculture around the world. The bacterium was monitored using spectrophotometry to estimate the growth rate of bacterial inocula incubated in a nutrient broth medium containing the compound paraquat at different concentrations. Moreover, the number of viable <a title="Bacteria" href="https://en.wikipedia.org/wiki/Bacteria">bacteria</a> cells in the samples was also estimated based on colony-forming units on the nutrient broth agar. Results showed that the compound paraquat promoted significant decreases in the growth rate of the <em>C. violaceum </em>bacterium in response to incubation time and dose tested. Significantly lower values of bacterial growth were also corroborated by counting the total number of colony-forming units at final concentrations of 100 (<10<sup>4 </sup>CFU) and 1,000 µg mL<sup>-1 </sup>(<10<sup>2 </sup>CFU) in comparison to control and 0 µg mL<sup>-1 </sup>(>10<sup>8 </sup>CFU) on the nutrient broth agar. Thus, the findings described herein report the effects of the compound paraquat dichloride hydrate on the <em>in vitro </em>growth rate of a <em>C. violaceum</em> wild type strain.