Research Projects

Lignocellulosic biowaste can be utilized for production of lactic acid and bioethanol leading to the development of feasible and economical process. This proposal aims at production of lactic acid and bioethanol using lignocellulosic biomass. Lactic acid producing bacteria will be isolated, identified and characterized. Lignocellulosic biomass (rice and wheat straw, rice stalk, rice husk, elephant grass, congress grass, millets etc.) will be subjected to different pre-treatment strategies. Saccharification of lignocellulosic biomass will be done by using different cocktails of combination of recombinant cellulases (CtGH5, CtGH8 and CtGH1) and hemicellulases (CtGH43, CtGH11 and PsGH10). Lignocellulosic hydrolysate will be used to produce lactic acid by isolated lactic acid producing bacteria and bioethanol by using mixed cultures (S. cerevisiae, P. stiptis, C. shehatae and Z. mobilis). Production of lactic acid and bioethanol will be statistically optimized and subsequently scaled up.

The project work aims to select a pretreatment method i.e. DES solvent system of ChCl and acetic acid (AA),as the best suitable pretreatment method for rice straw biomass. The ChCl:AA pretreatment was statistically optimized for maximal delignification and retainment of the total carbohydrate content (TCC) in the pretreated RS considering three significant pretreatment parameters; ChCl: AA molar ratio, time and temperature. For the efficient saccharification of choline chloride: acetic acid-pretreated RS, enzyme cocktail was formulated using crude(unpurified) recombinant bacterial hydrolytic enzyme cocktail consisting of cellulases (cellobiohydrolase, CtCBH5Aand cellulolytic chimeric enzyme, CtGH1-L1-CtGH5-F194A with a bi-functional activity of β-1,4-endoglucanaseand β-1,4-glucosidase) and xylanases (endo-1,4-β-xylanase, CtXyn11A and exo-1,4-β-xylosidase, BoGH43A) for the optimal proportion of each constituting enzyme for the efficient saccharification of choline chloride: acetic acid pretreated rice straw (CApRS) biomass. Finally, the CApRS biomass was used for bioethanol production using the formulated crude recombinant enzyme cocktail and Saccharomyces cerevisiae MTCC170. Pre-saccharification and simultaneous saccharification and fermentation of delignified CApRS biomass for bioethanol production were statistically optimized considering pre-saccharification time, enzyme dosage and fermentation temperature as a significant variable for maximizing ethanol yield and ethanol productivity. This study demonstrates a sustainable and efficient approach for lactic acid (LA) production from lignocellulosic agro-residues through an integrated bioprocess. Thermophilic, inhibitor-tolerant bacterial strains were successfully isolated and employed for high-temperature fermentation, eliminating the need for energy-intensive sterilization. Statistical optimization of mild chemical pretreatment ensured efficient sugar release while minimizing inhibitory by products. The developed co-culture system significantly enhanced fermentation efficiency, reducing process time and improving substrate utilization. Downstream purification via green solvent extraction further contributed to the eco-friendly nature of the process. Collectively, this work establishes a cost-effective and scalable bioprocess that valorizes agricultural waste into value-added LA, with potential industrial applicability in a circular bioeconomy framework. Further optimization of extraction efficiency could strengthen the economic viability of this sustainable approach.