Utilization of agro-industrial waste for the production of yellowish-orange pigment from Chryseobacterium artocarpi CECT 8497

Abstract

Bacterial pigments showed potential in various applications but the pigment production is limited due to high cost. This study reports on the optimization of yellowish-orange pigment production by Chryseobacterium artocarpi CECT 8497 in liquid pineapple waste medium using response surface methodology (RSM). Culture conditions affecting pigment production were optimized statistically in shake flask experiments. Liquid pineapple waste (LPW), L-tryptophan and potassium phosphate (KH2PO4) were the most significant variables affecting pigment production. Central composite design (CCD) and RSM analysis were adopted to investigate the interactions between variables and determine the optimal values for maximum pigment production. Evaluation of the experimental results signified that the optimum conditions for maximum production of pigment (152 mg l−1) in shake flasks were LPW 20% (v/v), L-tryptophan 125 g l1 and KH2PO4 12.5 g l−1. Production under optimized conditions is 3- folds higher than its production in nutrient broth. High pigment production was observed in 5 l (540 ± 14 mg l−1) and 50 l (200 ± 28 mg l−1) bioreactor under these optimized conditions. Two compounds from yellowish-orange pigment extracted from LPW were isolated and characterized using chromatography, ESI-MS and ATR techniques. Results showed that statistical optimization of medium composition influenced the yellowish-orange pigment production from C. artocarpi CECT 8497. The pigment was incorporated as natural colorant in soap making. Also, this is the first report optimizing the process parameters for yellowish-orange pigment production from C. artocarpi CECT 8497 in liquid pineapple waste.