Upcycling of tetra pack waste cellulose into reducing sugars for bioethanol production using Saccharomyces cerevisiae

Bioethanol production from waste materials offers a promising avenue for sustainable energy and waste management. In this study, fermentable sugars derived from tetra pack waste cellulose were bio-transformed into bioethanol using Saccharomyces cerevisiae. Tetra pack waste (180 g) yielded tetra pack cellulosic pulp (TPCP) of 145 g, after removing the different layers representing 80.56 ± 0.32% of the original weight. Cellulase from Bacillus sp. RL-07, with a cellulolytic potential of 6.98 ± 0.36 U/ml, released 32.72 ± 0.12 mg/ml of reducing sugars, achieving 44.60 ± 0.56% saccharification of TPCP under optimized conditions. Subsequent fermentation of the broth (1 L) with tetra pack cellulosic pulp hydrolysate (TPCPH) (50% v/v), containing 5.12 g of reducing sugars, by S. cerevisiae yielded 1.42 g of bioethanol per g of reducing sugars under optimized conditions, with a volume productivity of 0.24 g/l/h and a purity of 96.42% was confirmed by GC/MS analysis. The results of this study underscore the viability of utilizing tetra pack waste for bioethanol production, offering a sustainable solution for waste management while alleviating energy deficits and reducing environmental pollution. These findings align with objectives aimed at fostering sustainable progress and development.