Antimycotic effects of a prodigiosin producing Serratia marcescens rhizobacteria

Abstract

Pigmented Serratia spp. have antibacterial, antimalarial, antimycotic, immunomodulatory and antitumor activities. Here, a pigmented Rhizobacteria, Serratia spp. isolated from medicinal plant Plumbago indica was studied for its inhibitory effect towards Pythium myriotylum. Upon microscopic analysis, the pigment extract prepared from isolated Serratia spp. was found to cause remarkable distortion on fungal morphology, exhibiting an inhibition of 40%. Ginger rhizomes stand uninfected with this extract treatment similar to that of rhizome treated with commercial biocontrol agent Delfin (R), a Bacillus thuringiensis product. For structural characterization, the water-insoluble red pigment was extracted using acidified methanol. This was followed by analysis of thin layer chromatography (TLC), UV–Visible Spectrometry showing an absorbance maxima at 535 nm, FTIR and GC-MS revealing mass-to-charge ratio (m/z) of 310 [M + H]+ that confirmed the prodigiosin pigment. Therefore, the broad antifungal activity of the prodigiosin-producing strain indicates its potential to be exploited as a natural ecofriendly biocontrol agent.