Microbial conversion of tomato by a plant pathogenic bacterium Pectobacterium atrosepticum: A plant-microbial approach to control pathogenic Candida species

Abstract

This study was carried out to produce bioconverted products by microbial fermentation of tomato using a plant pathogenic bacterium Pectobacterium atrosepticum and to evaluate their in vitro antimycotic effect against pathogenic Candida species. The bioconverted products (500 μg/disc) provoked promising antimycotic effects against pathogenic isolates of Candida species as shown by the diameters of zones of inhibition (9 ± 0.6 to 14 ± 0.4 mm), along with their respective minimum inhibitory and minimum fungicidal concentration values, which increased from 250 to 1000 and 250 to 2000 μg/mL, respectively. With the viable counts of the tested fungal pathogens, exposure of the bioconverted products revealed a remarkable antimycotic effect. In addition, the morphology of a clinical isolate of C. glabrata KBN06P00368, visualized by scanning electron microscopy, showed a severe detrimental effect produced by the bioconverted products at the minimum inhibitory concentration (250 μg/mL). The bioconverted products significantly inhibited the in vitro growth of all the tested clinical and pathogenic laboratory isolates of Candida species. This study confirmed the potent antimycotic efficacy of the bioconverted products of tomato, hence justifying the therapeutic uses of bioconverted products in pharmaceutical preparations as an alternative approach to support the antifungal activity of conventional antimycotics.