Bioethanol production from agricultural wastes: An overview

http://repositorium.sdum.uminho.pt/bitstream/1822/11360/1/Mussatto_Biotechnology%20Advances.pdf

Technological trends, global market, and challenges of bio-ethanol production

Current developments in solid-state fermentation

Due to increasing population and industrialization, the demand of energy is increasing day by day. Simultaneously, the worldwide bio-ethanol production is increasing constantly. The maize, sugarcane and sugar beets are major traditional agricultural crops used as bio-ethanol production but these crops are unable to meet the global demand of bio-ethanol production due to their primary value of food and feed. Hence, cellulosic materials such as agro-residues are attractive feedstock for bio-ethanol production. The cellulosic material is the most abundant biomass and agro-residues on the earth. Bio-ethanol from agro-residues could be a promising technology that involves four processes of pre-treatment, enzymatic hydrolysis, fermentation and distillation. These processes have several challenges and limitations such as biomass transport and handling, and efficient pre-treatment process for removing the lignin from the lignocellulosic agro-residues. Proper pre-treatment process may increase the concentrations of fermentable sugars after enzymatic hydrolysis, thereby improving the efficiency of the whole process. Others, efficient microbes and genetically modified microbes may also enhance the enzymatic hydrolysis. Conversion of cellulose to ethanol requires some new pre-treatment, enzymatic and fermentation technologies, to make the whole process cost effective. In this review, we have discussed about current technologies for sustainable bioethanol production from agro-residues.

Sustainable bio-ethanol production from agro-residues: A review

Organic solvent pretreatment of lignocellulosic biomass for biofuels and biochemicals: A review

Lignocellulosic ethanol in India: Prospects, challenges and feedstock availability

In recent years, growing attention has been focused on the use of lignocellulosic biomass as a feedstock for the production of ethanol, a possible renewable alternative to fossil fuels. Several pretreatment processes have been developed for decreasing the biomass recalcitrance, but only a few of them seem to be promising. In this study, effect of various organic solvents and organic acids on the pretreatment of sugarcane bagasse was studied. Among the different organic acids and organic solvents tested, formic acid was found to be effective. Optimization of process parameters for formic acid pretreatment was carried out. The structural changes before and after pretreatment was investigated by scanning electron microscopy, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) analysis. The X-ray diffraction profile showed that the degree of crystallinity was more for pretreated biomass than that of untreated. The FTIR spectra shown at the stretching of hydrogen bonds of pretreated sugarcane bagasse arose at higher number. It also revealed that the cellulose content in the solid residue increased because the hemicelluloses fraction in raw materials was released by acid hydrolytic reaction.

Formic Acid as a Potential Pretreatment Agent for the Conversion of Sugarcane Bagasse to Bioethanol

Realization of hazardious effects of chemical fungicides has led to an interest in the usage of biocontrol agents. The present study, therefore, evaluates the biocontrol efficacy of Western Ghats (India) soil bacterial isolates. A potential strain NII 1006 was evaluated for its antagonistic property against a diverse range of moulds and yeasts. The strain was characterized morphologically, biochemically and molecularly, which revealed the isolate belonged to Streptomyces genus. Organic solvent extracts of NII 1006 culture filtrates inhibited the growth of the test pathogens indicating that growth suppression was due to extracellular anti-fungal metabolites present in the culture filtrates. The strain produced extracellular chitinase enzyme in addition to some stable partially purified anti-fungal compounds. Morphological changes such as hyphae degradation into debris and abnormal shapes were observed in test fungi and yeast grown on potato dextrose broth that contained the NII 1006 culture filtrate. The cell free supernatant has a tolerance to wide range of pH, temperature and enzymes such as lipase and protease. The biocontrol potential of NII 1006 strain may be correlated significantly with their ability to produce antibiotics as well as extracellular hydrolytic enzymes particularly chitinolytic enzyme.

http://nopr.niscair.res.in/bitstream/123456789/29756/1/IJEB%2052%2811%29%201138-1146.pdf

Kuttavan Valappil Sajna

Papers

Lignocellulosic ethanol in India: Prospects, challenges and feedstock availability

Formic Acid as a Potential Pretreatment Agent for the Conversion of Sugarcane Bagasse to Bioethanol

Anti-fungal potentials of extracellular metabolites of Western Ghats isolated Streptomyces sp. NII 1006 against moulds and yeasts.