Microbial production of 2,3-butanediol from rice husk using anaerobic Clostridium species

Abstract

Interest in the area of biomass based-product production is increasing all over the world due to the environmental challenges posed by fossil fuel and fear of its extinction. Production of biofuel and other compounds especially from agricultural waste can reduce these environmental problems because of its sustainability and environmentally friendliness. One of the major petrochemical product widely used in many industries is 2,3-butanediol and was found to be produced from agricultural wastes by microorganisms. Therefore, Microbial production of 2,3-butanediol from rice husk using Clostridium species was investigated in this research. Structural composition of the rice husk was determined before and after pretreatment. Hemicellulose and lignin content of rice husk was determined after extraction while cellulose was determined as the difference from the extractives, hemicelluloses and lignin. Dilute (2%) NaOH was used for the pretreatment of rice husk. Hydrolysis was carried out using Aspergillus niger and reducing sugar released was determined using standard method with UV-VIS spectrophotometer. Clostridium species was isolated from sugarcane bagasse, identified using basic morphological and molecular biology techniques. The fermentation of rice husk was performed using the Clostridium species. Fermentation by-product was determined using Gas Chromatography Mass-spectrometry. Cellulose content increased from 32% before pretreatment to 53.3% after pretreatment, lignin increased from 8.4% before pretreatment to 30.7% after pretreatmemt and hemicellulose decreased from 30% before pretreatment to 8% after pretreatment. A total of 1.05 g/l of reducing sugar was released after enzymatic hydrolysis of the rice husk with Aspergillus niger. Alcohol 2,3-butanediol (0.6%) and Furfuryl alcohol (0.45%) were detected in the by-product of fermentation. Other compounds detected are fatty acids that ranges from C16 to C25 with 9,12-Octadecanoic acid as the major fatty acid. From the results of this work, Rice husk was found to have substantial amount of sugar (cellulose and hemicelluce) that can be converted to valuable product including 2,3-butanediol.
 Keywords: Biofuel, Bio-refinary, Cellulose, Clostrudium, fermentation.

Screening Bacterial Strains Capable of Producing 2,3-Butanediol: Process Optimization and High Diol Production by Klebsiella oxytoca FMCC-197

“…The potential of the strain to convert different hexoses and pentoses into BDO proves that it can be efficiently used in the above low-cost residues, which only require supplementation with small quantities of mineral salts and nitrogen sources. Current research supports several studies that propose that the conversion of food waste into BDO via microbial fermentation is a promising way to reduce waste disposal into the environment and produce sustainable chemicals [45][46][47]. Additionally, the strain K. oxytoca FMCC-197 could ferment xylose, which encourages further investigation into using lignocellulosic biomass such as press cake from fruits and vegetables as a substrate that can lead to satisfying BDO production.…”

Rice-Husk-Based Materials for Biotechnological and Medical Applications

“…According to the authors, the results indicate that the immobilization of enzymes on large volumes of available renewable carriers reduces the environmental impact of fossil-based carriers, increasing the economic and environmental efficiency of the processes. The article [11] examined the potential application of rice husk as an environmentally friendly bio-resource for the production of butanediol. 2, 3-butanediol has a wide range of applications, ranging from petrochemicals to widely used food and pharmaceuticals in many industries.…”

“…Given the fact that all the above microorganisms are classified as risk group 2, according to the World Health Organization, the microbial production of 2,3-butanediol from rice husks using Clostridium species was investigated in this study. Rice husks contain significant amounts of sugars, such as cellulose and hemicellulose, which can be converted into valuable products such as 2,3-butadieneone and 2,3-butanediol [11].…”

“…In [12,13], studies on the extraction of fusicoccin on a sorbent from rice husk were presented (Figure 2). The article [11] examined the potential application of rice husk as an environmentally friendly bio-resource for the production of butanediol. 2, 3-butanediol has a wide range of applications, ranging from petrochemicals to widely used food and pharmaceuticals in many industries.…”