Production optimization and enhancement by lignocellulosic biomass of a broad-spectrum antibacterial 5-butyl-2-pyridine carboxylic acid from Aspergillus fumigatus nHF-01

Abstract

The main objectives of the study are to optimize and enhance the production of potent broad-spectrum antimicrobial compound (AMC) 5-butyl-2-pyridine carboxylic acid by Aspergillus fumigatus nHF-01 (GenBank Ac. No.: MN190286). The submerged fermentation (SmF) variants were optimized through response surface methodology. The production enhancement was done through solid-state fermentation (SSF) with lignocellulosic biomass. The strain produced a high amount (31.5 mg/100 ml) of AMC in 4 % malt extract (ME) and yeast extract (YE) (w/v, each) broth in a shake flask culture at 20 °C for ten days. Moreover, the yield had increased 32-fold with SSF of washed chopped bagasse in the same culture conditions. A significant variation was observed in the fungal hyphae biomass, extractable compound and specific activity in both SmF and SSF. Thus, a low-cost media with lignocellulosic agro residues could be used for large-scale production of the 5-butyl-2-Pyridine carboxylic acid from A. fumigatus nHF-01.