Sustainable biosynthesis of β-carotene utilizing sugarcane bagasse: depiction and biotechnological implications

This study focused on optimizing β-carotene production by Nesterenkonia sp. K-15–9-6 through submerged fermentation (SmF), which aims majorly for cost reduction and eco-friendliness. A total of eight different agro-food wastes were explored for designing the production medium among which sugarcane bagasse showed prominent amounts of β-carotene. Upon optimization of various factors, it was observed that the maximum pigment (820µg/ml) was produced utilizing 3g (w/v) sugarcane bagasse, 1% (v/v) glycerol, 2.5% (w/v) NaCl, 0.5% (w/v) peptone, and 0.5% (w/v) dextrose (inducer). The solvent extraction method suggests that methanol proved to be the best solvent for pigment extraction. The β-carotene product confirmation was done via absorption maxima, thin layer chromatography (TLC), high-performance liquid chromatography (HPTLC), Fourier transformation infrared spectroscopy (FTIR), and mass spectrophotometry (MS). Phyto-toxicity assay of pigment on Sorghum (Sorghum bicolor), Fenugreek (Trigonella foenum-graecum), and Fennel seed (Foeniculum vulgare) confirmed the safety as well as plant growth-promoting ability. The β-carotene has varied applications such as antimicrobial, antioxidant, textile dyeing, food additives, cosmetics, and candles. The findings emphasize the viability and sustainability of utilizing sugarcane bagasse, for biosynthesis of β-carotene in an economic way.