Mehta, ShikhaSonia2023-03-202023-03-202022-12https://krishikosh.egranth.ac.in/handle/1/5810195511Bioethanol is considered as a potential liquid fuel due to limited natural resources. Lignocellulosic biomass is investigated as a potential substrate for bioethanol production. Water hyacinth (Eichhornia crassipes) is one of the most abundant lignocellulosic materials, which consist of about 35% hemicellulose, 26% cellulose and 11 % lignin. A pre-treatment process is essential to remove lignin, reduce crystallinity and increase the porosity of material making cellulose desirable to hydrolysis. To hydrolyse the cellulose, cellulases are required which increase the cost of ethanol production. Therefore, to make the process cost-effective, there is need to utilize microbial cellulase. In the present study, a total 43 bacterial and 16 fungal isolates were retrieved from 3 different samples such as soil from CCS HAU, Hisar, decaying woody material from village Mirchpur, Hisar and cattle dung from CCS HAU, Hisar. All the bacterial and fungal isolates were screened for cellulase production on the basis of zone of hydrolysis on carboxymethyl cellulose (CMC) agar medium. Out of 43 bacterial isolates, 13 bacterial isolates showed zone formation on CMC agar medium and three isolates i.e. SB2, SB4 and SB10 showed large zone. Out of 16 fungal isolates, 10 fungi showed the zone formation on CMC agar medium and WF1 isolate showed large zone of hydrolysis. Cellulase activity of SB4 and WF1 was determined and found to be 276.83 IU/mL and 230.62 IU/mL, respectively. Bacterial isolate SB4 was biochemically characterized and stained using Gram’s staining. SB4 was found to be Gram positive. Pre-treatment of water hyacinth was done using acid (1% H2SO4) as well as alkali (2% NaOH). Acid pre-treated water hyacinth consisted of 30.23% cellulose, 23.50% hemicellulose and 5.83% lignin and alkali pre-treated water hyacinth consisted of 29.86% cellulose, 24.30% hemicellulose and 6.13% lignin. Crude enzymes of bacterial isolate SB4 and fungal isolate WF1 were used for enzymatic hydrolysis. Hydrolysis of acid pre-treated water hyacinth with crude enzyme obtained from SB4 isolate released 65.74 mg/g total reducing sugars after 120 min of incubation. Fermentation of hydrolysate was carried out using Saccharomyces cerevisiae HAU-1. Different conditions such as pitching rate, slurry concentration and nitrogen sources were optimized for maximizing ethanol production. Fermentation of hydrolysate of acid pre-treated water hyacinth supplemented with 0.15% urea resulted in production of 1.77% (v/v) ethanol after 72 h of incubation using crude enzyme obtained from SB4 isolate.EnglishThesis