The major constituent of plant cell wall is lignocellulose. Plant biomass mostly consist of cellulose, hemicellulose and lignin alongside little measures of pectin, protein, extractives (dissolvable nonstructural materials, for example, sugars, nitrogenous material, chlorophyll, waxes) and ash. Lignocellulosic biomass is the most abundant organic material in nature. There is an expected yearly overall production of 10–50 billion dry tons representing about 50% of the worldwide biomass yield (Parveen et al. 2009).
Numerous physicochemical, structural and compositional variables decrease the digestibility of cellulose present in lignocellulosic material. So a treatment is required to increase the digestibility of lignocellulose biomass by exposing the cellulose present in plant fibers. Different techniques have been utilized for treatment, including chemical treatment, ammonia fiber explosion, biological treatment and steam explosion to modify the cellulosic structure to increase the availability of cellulose for digestion (Haoran et al. 2013). At that point, acids, bases and enzymes might be utilized to break down the cellulose into its respective sugars. Cellulolytic enzymesare broadly used to break down cellulose into its constituent sugars.
Among various agricultural wastes a broadly available waste is Rice husk (RH) which is rich in lignocellulosic material. Internationally, roughly 600 million tons of rice paddy is delivered every year. By and large 20% of the rice paddy is husk, giving a yearly aggregate generation of 120 million tons (Abbas et al. 2010). Pakistan is a rice producing country a great part of the husk produced from processing of rice is either blazed or dumped as waste. Rice husk yield in Pakistan is more than 1780 thousand tons every year (Asif et al. 2013).
Rice husk produced during rice refining, makes disposal issue because of less business interest. Additionally, handling and transportation of RH is hazardous because of its low density. Rice husk ash (RHA) is an incredible environmental risk bringing about harm to land and encompassing range here it is dumped. Thus, business utilization of rice husk and its ash is the option answer for disposal problem (Dilip et al. 2014).
RH are essentially made up of lignocellulose (60wt. %) and silica (11wt. %). The greater part of past investigations concentrated on the preparation of silica or other silicon based materials from RH, while the lignocellulose in RH was mostly glazed and then wasted. Thus, a methodology for comprehensive usage of RH has been produced to expand its digestibility by the breakdown of lignocellulosic mass. (Ajay et al. 2012)
Numerous techniques have been adopted for treating lignocellulosic feedstocks. However just a few of them appear to be encouraging. These treatment techniques include dilute acid treatment, steam blast (CO2 blast), pH controlled water treatment, ammonia fiber expension, ammonia recycle percolation (ARP) and lime treatment. Some survey articles have been appeared for microbial biomass treatment. But the present study gave presentations on organosolv treatment process. Despite the fact that organosolv treatment is more expensive at present than the leading treatment forms, it can give some significant side products. It appears that organosolv treatment is more practical for biorefinery of lignocellulosic biomass which considers the usage of every bit of biomass parts. An essential streamlining and usage of side products may lead the organosolv treatment to be a guaranteeing one for bio refining lignocellulosic feedstock in future. Organosolv treatment yields three different parts: dry lignin, a watery hemicellulose stream and a moderately pure cellulose division (Xuebing et al. 2009).