In this paper, enzymatic SACCHARIFICATION of poplar wood has been studied. Poplar wood samples were subjected to chemical processing (acidic delignification and swelling by ammonium hydroxide) under selected operational conditions. By removal of lignin along with recovery of cellulose both at the level of 80% solid residues were obtained that were, then, used as the substrate for enzymatic hydrolysis using a mixture of the following two enzymes, cellulose and cellobiase. Increase in the swellingcapacity of the cellulose substrate along with decrease of the polymerization degree of lignocellulosicmaterials facilitates the action of celluloses enzymes. Considering selected operational conditions in the enzymatic SACCHARIFICATION of the wood residues, glucose was produced at the level of 30 g/l. The experimental results were fitted to the hyperbolic empirical model. There was a close relationship between the experimental and the calculated results in some of the enzymatic treatments.

A lot of recent research in the biomass sector is focusing on how to improve the efficiency of biomass resources. Pretreatment of biomass resources is a novel approach and has gained a lot of attention in the last decade. A review of modern methods and the latest technologies of enhancing the enzymatic scarification of sugarcane bagasse are presented in this work. This paper looks at the very recent developments in this field. Use of such advanced methods as coupling ionic liquid pretreatment with supercritical fluids and ultrasound, irradiation is taking us swiftly towards the ultimate goal which is achieving 100% yield at minimum cost with no adverse environmental effects. However, Optimum process conditions for these methods are yet to be discovered. There is a need to optimize the processes and learn completely about the reaction mechanism in order to shift from lab scale to pilot scale and ultimately to the industrial level. An effort is made to report the latest work and because of it, this paper contains about 95% citations from papers within the last five years. In the end, useful recommendations are given in the conclusion section.

In this study, sono-assisted dilute sulfuric acid process was evaluated for its viability of simultaneous pretreatment and SACCHARIFICATION of rice straw. Three critical factors for simultaneous pretreatment and SACCHARIFICATION process, such as sonication time (30-50 min), temperature (70-90oC), and acid concentration (5-10%), were optimized to maximize reducing sugar yield using Box-Behnken design and response surface methodology. The response surface methodology model was found to be adequately fitted to the obtained data. Simultaneous pretreatment and SACCHARIFICATION factors were optimized at sonication of 50 min, 80oC and an acid concentration of 10% yielding the maximum sugar content (31.78 g/100 g of biomass). Scanning electron microscopy revealed that the smooth surface of raw biomass was altered into a rough and porous surface as a result of sugar release, which showed the prospective feasibility of simultaneous pretreatment and SACCHARIFICATION process. This process integration may lead to develop economical bioethanol production facility. However, further research is required to make this process industrially viable.

Introduction: The increased need for a considerable β-glucosidase activity, especially in the enzymatic SACCHARIFICATION of cellulose for bioenergy, has strongly stimulated the identification of effective β-glucosidase producing microbes. This study was conducted to optimize culture condition for β-glucosidase production from the identified new isolate of Bacillus subtilis (B1) and to find out an ideal condition for β-glucosidase activity. Materials and Methods: For β-glucosidase production, the bacterium was cultivated in a basal medium. The culture condition was optimized at several pH, different temperatures, varying cultivation periods, and various substrate concentrations. Finally, the activity of the β-glucosidase enzyme was investigated at different incubation periods, pH, temperatures, metal ions, and various percentages of methanol. The activity of β-glucosidase was measured by the capability of crude enzyme to convert pNPG (p-nitrophenyl-β-D glucopyranoside) into yellow product PNP (p-nitrophenol). Results: Cellulolytic bacterial strain B. subtilis (B1) showed high potentiality for β-glucosidase production at a pH of 7. 0 after 24 hours incubation at 40° C. The highest level of enzyme production was achieved when 3% of CMC was provided in the culture medium. Optimum reaction conditions for β-glucosidase activity were shown to be 10 minutes, 60° C and at pH 7. Salts like Magnesium Sulfate (MgSO4), Calcium Chloride (CaCl2), and Manganese Sulfate (MnSO4) positively influenced the activity where NaCl and KCl had negative effects. The presence of methanol (80%) appreciably enhanced the activity of enzyme. Conclusions: Complete SACCHARIFICATION of different industrial processes can be augmented by using this novel β-glucosidase produced by B. subtilis strain isolated from effluent of biogas plant.

Sorghum bicolor L., a plant of Gramineae family is a perenial grass which is grown in many parts of tropical and warm temperates of the world. Sorghum seeds are rich in carbohydrates and can be used as fermentation medium providing it is produced through proper extraction and sacharification processes. In this study, the fermentation capacity of an aqueous or ethanolic extract from sorghum seed was investigated in Labscale bioreactors by using three selected Lactobacillus species including L. delbrueckii, L. acidophilus and a new isolated strain identified as a Lactobacillus sp.Among the selected bacterial species, Lactobacillus delbrueckii was found to have unique characteristics as it could tolerate different physico-chemical conditions.Compared to other species, L. delbrueckii could remain metabolically active in high concentration of NaCl and lactic acid, which is particular to the fermentation of sorghum seed extract neutrilized by NaOH. L.delbrueckii could also tolerate high temperature and, additionally, was able to produce more lactic acid in high concentration of carbohydrate during fermentation process (Yield 85-90%). In conclusion, the results of this study demonstrated that hydrolysed sorghum seed extract has enough nutrients to support the efficient growth of lactic acid bacteria and production of lactic acid under favorable conditions (37oC, 100 g/L initial carbohydrate concentration).