Bioethanol production of second generation from corn cob

Bioethanol production from lignocellulosic materials has several environmental and economic advantages. In this work, corn cob was used to produce ethanol by fermentation. The cob was grounded, hydrolyzed chemically, and then enzymatically. Later, hydrolysates were used as a carbon source to formulate culture media that were inoculated with Saccharomyces cerevisiae; hollocellulose content was quantified by the ASTM D-1104 method; cellulose content by the TAPPTI 212 method; lignin content by the NREL / TP-510-42618 method; and ethanol was quantified by HPLC. In fermentation, bioethanol yields of up to 3.5 g / L were found, equivalent to YP/S value of 0.46, representing approximately 90% of the theoretical yield.

Valorization of Waste Lignocellulose to Furfural by Sulfonated Biobased Heterogeneous Catalyst Using Ultrasonic-Treated Chestnut Shell Waste as Carrier

Recently, the highly efficient production of value-added biobased chemicals from available, inexpensive, and renewable biomass has gained more and more attention in a sustainable catalytic process. Furfural is a versatile biobased chemical, which has been widely used for making solvents, lubricants, inks, adhesives, antacids, polymers, plastics, fuels, fragrances, flavors, fungicides, fertilizers, nematicides, agrochemicals, and pharmaceuticals. In this work, ultrasonic-treated chestnut shell waste (UTS-CSW) was utilized as biobased support to prepare biomass-based heterogeneous catalyst (CSUTS-CSW) for transforming waste lignocellulosic materials into furfural. The pore and surface properties of CSUTS-CSW were characterized with BET, SEM, XRD, and FT-IR. In toluene–water (2:1, v:v; pH 1.0), CSUTS-CSW (3.6 wt%) converted corncob into furfural yield in the yield of 68.7% at 180 °C in 15 min. CSUTS-CSW had high activity and thermostability, which could be recycled and reused for seven batches. From first to seventh, the yields were obtained from 68.7 to 47.5%. Clearly, this biobased solid acid CSUTS-CSW could be used for the sustainable conversion of waste biomasses into furfural, which had potential application in future.

Bioaugmentation of Corn Stalks Saccharification with Aspergillus Fumigatus Under Low/High Solid Loading Culture

Decomposed the dense structure of lignocellulosic feedstocks and hydrolysis lignocellulose into monosaccharide were essential prerequisite for bio-energy production at this level. In this study, a cellulosic fungi Aspergillus fumigatus CLL was conducted to pretreated the corn stalks under high/low solid loading culture to enhanced the cellulase saccharification performance. The results indicated that A. fumigatus CLL decomposed the corn stalks effectively under high/low solid loading culture, what’s more, A. fumigatus CLL completed the T. reesei cellulase system and promoted the corn stalks saccharification performance. 25.2% lignin was degraded after A. fumigatus CLL treated just for two day under low solid loading culture with holocellulose loss less than 10%. Meanwhile, the β-glucosidase of A. fumigatus CLL complemented the incomplete cellulase system of T. reesei, the maximum saccharification ratio of sample saccharified by T. reesei cellulase combined A. fumigatus CLL was comparable with the sample saccharified by commercial cellulase. Compared with raw corn stalks, the saccharification ratio of pretreated sample increased 3.1-3.4 fold. These results demonstrated that A. fumigatus CLL can be used for pretreatment of lignocellulosic materials to enhanced the saccharification performance.

Pretreated Sugarcane Bagasse Result in More Efficient Degradation by Streptomyces sp S2

Streptomyces genera plays important role in lignocellulose degradation. Many research founds Streptomyces has cellulolytic and ligninolytic enzymes that sufficient to degrade lignocellulosic materials. However, minimum lignocellulosic material condition that can efficiently degraded by Streptomyces sp. has not been fully understood. In this research, three pretreament conditions (physical, alkaline-hydrotermal, and hydrogen-peroxide chemical treatments) of sugarcane bagasse used as lignocellulosic material, to further degraded by Streptomyces sp. S2. Lignocellulose component measurement conclude that raw (physical treated only) bagasse wasn’t efficiently degraded by Streptomyces sp S2. Hydrogen-peroxide was effective on reducing both syringil and guaiacyl lignin, meanwhile alkaline-hydrotermal pretreatment was very effective on reducing syringil lignin. This study suggest that hydrogen-peroxide pretreatment can be used in many type of lignocellulosic material, which can be further degraded by Streptomyces sp. S2. Alkaline-hydrotermal preteatment on the other hand is best suited to degrade lignocellulosic material that have high percentage of syringil lignin.

Delignification of Lignocellulosic Biomass

Delignification is the process of breaking lignocellulose into lignin, cellulose, and hemicellulose. The presence of lignin in lignocellulosic materials results in the limited utilization of cellulose. This article discusses lignin and the delignification process. There are various delignification methods from the literature study, namely physical, chemical, semi-chemical, mechanical, and enzymatic.

Effects of C/N Ratio on Lignocellulose Degradation and Enzyme Activities in Aerobic Composting

Lignocellulosic materials have a complex physicochemical composition and structure that reduces their decomposition rate and hinders the formation of humic substances during composting. Therefore, a composting experiment was conducted to evaluate the effects of different C/N ratios on lignocellulose (cellulose, hemicellulose and lignin) degradation and the activities of corresponding enzymes during aerobic composting. The study had five C/N ratios, namely, T1 (C/N ratio of 15), T2 (C/N ratio of 20), T3 (C/N ratio of 25), T4 (C/N ratio of 30) and T5 (C/N ratio of 35). The results showed that treatments T3 and T4 had the highest rate of degradation of cellulose and hemicellulose, while treatment T3 had the highest rate of degradation of lignin. Among the five treatments, treatment T3 enhanced the degradation of the lignocellulose constituents, indicating a degradation rate of 6.86–35.17%, 15.63–44.08% and 31.69–165.60% for cellulose, hemicellulose and lignin, respectively. The degradation of cellulose and lignin occurred mainly at the thermophilic and late mesophilic phases of composting, while hemicellulose degradation occurred at the maturation phase. Treatment T3 was the best C/N ratio to stimulate the activities of manganese peroxidase, lignin peroxidase, polyphenol oxidase and peroxidase, which in turn promoted lignocellulose degradation.