Wheat Bran Hydrolysate Culture Medium Design for Talaromyces purpureogenus CFRM02 Pigment Production and Colour Characteristics

Abstract

Wheat bran hydrolysate (WBH) in combination with carbon and nitrogen was utilised as substrate for pigment production by Talaromyces purpureogenus CFRM02. Pigment yield was signi cantly increased (≈ 3 fold: OD units and ≈ 2 fold: a * value) by xylose supplementation with WBH compared to other carbon sources. Whereas 1% xylose supplementation increased pigment production (1.57 ± 0.05 OD Units and 49 ± 1.62 a * value). Pigment yield was low when WBH supplemented with 0.3% nitrogen sources.However signi cant increase (≈ 2-2.5 fold, OD units and a * value) was observed, when yeast extract (1.2%), nitrate of sodium (1.2%) and potassium (1.6%) were supplemented. Accordingly, 16 WBH media were designed by supplementing carbon and nitrogen. Interestingly the pigment production was signi cantly increased (1.59 OD units and 32 a * value) in the medium supplemented with 4% carbon and 0.9-1.2% nitrogen. T. purpureogenus CFRM02 was able to co-utilize xylose, fructose and glucose in WBH medium. The CIE Lab values indicated that, pigment characteristics differed signi cantly among the media. Apparently, T. purpureogenus CFRM02 possess alternative gene(s) or pathway(s) for xylose metabolism and channelled towards pigment biosynthesis. Comparative results revealed that, 1% xylose supplementation to WBH makes the fermentation process economically competitive for pigment production.