Evaluation of Biogas through Chemically Treated Cottonseed Hull in Anaerobic Digestion with/without Cow Dung: An Experimental Study

Cow dung is generally used as the feedstock material for the anaerobic digestion to produce biogas. A selection of alternate biomass material is needed to reduce the consumption or to eliminate the use of cow dung. Recently, cottonseed hull has been considered as the primary substrate to produce biogas. In this paper, the effect of biogas production on anaerobic co-digestion of cow dung with pre-treated cottonseed hull using different concentrations of sulfuric acid, hydrochloric acid, hydrogen peroxide, and acetic acid is investigated. Sodium hydroxide and calcium hydroxide are used at different concentrations for pre-treatment of cottonseed hull. The enhancement of biogas production from the batch reactors at mesophilic temperature (35 ± 2 ℃) is observed for mono- and co-digestion of cow dung with treated cottonseed hull. Maximum biogas yield is achieved for the treated cottonseed hull at 6% sodium hydroxide during mono digestion and at 6% calcium hydroxide during co-digestion.

Development of Mycelium Materials Incubating Pleurotus Ostreatus Fungi With Different Substrates Composed of Poplar Sawdust and Cottonseed Hull

The mycelium materials incubating Pleurotus ostreatus fungi based on different substrate compositions were developed, the main components of which were poplar sawdust and cottonseed hull in different proportions. The hyphae on the surface of the samples become dense from appearance due to the addition of cottonseed hull. The Fourier Transforms Infrared analysis revealed that the cellulose, hemicellulose and lignin in substrates of all samples were degraded in different degrees owing to utilization by hyphae growth. The morphology and mechanical properties of the mycelial materials changed as the substrate compositions varied. The difference of properties among all mycelium materials was mainly attributed to the growth of mycelium and different substrate compositions. And the mycelium material (the ratio of poplar sawdust to cottonseed hull was 1) exhibited highest strength and lowest compression set, indicating that its size recovery capability was best. In comparison, the substrate of this material was more favorable to the growth of the mycelium and it showed optimal comprehensive performance among all samples. The mycelium material showed good potentiality for packaging application.

Laccase activity from Pleurotus ostreatus and Flammulina velutipes strains grown on agro- and forestry residues by solid-state fermentation

Laccase activity from Pleurotus ostreatus and Flammulina velutipes strains was investigated with various agro- and forestry residues by solid-state fermentation. Different species or strains belonging to the same species had the unique capacity of secreting laccase on solid-state fermentation with various agro- and forestry residues. Overall, the capacity of secreting laccase for P. ostreatus strains was superior to F. velutipes strains due to the value of maximum activity on various agro- and forestry residues, except on the stalk of straw. Compared with Populus beijingensis, corncob, and stalk of straw, the presence of cottonseed hull was helpful to improve laccase activity for P. ostreatus strains because the maximum laccase activity from cottonseed hull was higher than that from the other three agro- and forestry residues. The presence of stalk of straw was more helpful to improve laccase activity for F. velutipes strains because of the maximum laccase activity from stalk of straw was higher that from Populus beijingensis, corncob, and cottonseed hull. These results indicated the importance of selecting suitable agro- and forestry residues for fungi producing laccase. These findings contributed to the selection of suitable strains to obtain an integrated application of low-cost laccase in the factory.

In situ rumen degradation characteristics and bacterial colonization of whole cottonseed, cottonseed hull and cottonseed meal with different gossypol content

Regarding whole cottonseed (WCS), cottonseed meal (CSM), and cottonseed hull (CSH), in situ rumen incubation was applied to determine their nutrient and gossypol degradation characteristics and bacterial colonization profile in lactating Holstein cows. Nylon bags containing the cotton by-products were incubated for 0, 6, 12, 24, 36, 48 and 72 h in the rumen, respectively. The relationship between nutrient degradability and free gossypol (FG) content were examined, and the differences in the composition and inferred gene function of the colonized microbiota were studied. As a result, CSM presented highest effective degradability of dry matter, neutral detergent fibre and acid detergent fibre, but the highest effective degradability of crude protein was found in WCS. Free gossypol disappearance rate increased significantly in the first 6 h, and it reached approximately 94% at 72 h of incubation among all samples. The level of FG did not affect nutrient degradability of cotton by-products. Significant differences were noted in attached bacterial community structure among cotton by-products after 24 h rumen incubation. Among the most abundant taxa at genus level, a greater abundance of Cercis gigantea and Succiniclasticum was observed in WCS samples, whereas the CSH and CSM samples contained a greater proportion of Prevotella 1 and Rikenellaceae RC9 gut group. The redundancy analysis revealed that the level of neutral detergent fibre, ether extract, and FG in cotton by-products were significantly positive related with the composition of the attached bacteria. Collectively, our results revealed the dynamics of degradation characteristics, and the difference in the composition of bacterial colonization. These findings are of importance for the targeted improvement of cotton by-products nutrient use efficiency in ruminants and further understanding of the gossypol degradation mechanism in the rumen.

Evaluation of laccase production by two white-rot fungi using solid-state fermentation with different agricultural and forestry residues

Pleurotus ostreatus and a newly isolated Ganoderma lingzhi strain were evaluated for their laccase secretion capacity by solid-state fermentation with different agricultural and forestry residues. There was a significant difference among fungi for biosynthetic potential. In principle, the laccase secretion capacity of P. ostreatus CY 568 was stronger than that from G. lingzhi Han 500. Different species of fungi had a preference for agricultural and forestry residues. The presence of cottonseed hull and Populus beijingensis were helpful for accelerating the rate of laccase enzyme production of P. ostreatus CY 568. Cottonseed hull and corncob were useful for improving the production of laccase from G. lingzhi Han 500. Continuous and stable laccase production was found on cottonseed hull by P. ostreatus CY 568 and G. lingzhi Han 500. Maximum laccase activity obtained from P. ostreatus CY 568 on Toona sinensis, Sophora japonica, Salix babylonica, Populus beijingensis, corncob, cottonseed hull, and straw of Oryza sativa was higher than that from G. lingzhi Han 500, and was nearly 1.16-fold, 1.59-fold, 3.32-fold, 1.39-fold, 1.08-fold, 1.08-fold, and 1.36-fold, respectively. These findings will be helpful for developing new productive strains and expanding more species for industrial application to obtain efficient and low-cost laccase.

Comparative study on laccase activity of white rot fungi under submerged fermentation with different lignocellulosic wastes

Different Pleurotus ostreatus and Flammulina velutipes species were compared relative to their ability to produce laccase in submerged fermentation of various lignocellulosic wastes. Fungi cultivation in identical culture conditions revealed wide differences among both species and strains of the same species. The laccase secretion ability of P. ostreatus strains was superior to F. velutipes strains. Maximum laccase production on cottonseed hull, corncob, and poplar wood was secreted by P. ostreatus CY 568, P. ostreatus CCEF 89, and P. ostreatus CY 568, respectively. The nature of lignocellulosic materials played an important role in determining the expression of laccase potential of fungi. The presence of cottonseed hull improved laccase activity and accelerated the rate of enzyme production. Maximum laccase production on cottonseed hull was nearly 1.29-fold and 1.53-fold higher than that on corncob and poplar wood, respectively. Laccase activity was detected in almost all tested strains on cottonseed hull on the first day, while only a few strains on poplar wood and corncob were detected on the first day. These findings will be helpful for selecting the appropriate strain in industrial applications and for optimization of integrated industrial laccase production.

Micro-Structure Determines the Intrinsic Property Difference of Bio-Based Nitrogen-Doped Porous Carbon—A Case Study

Biomass-derived porous carbon materials have drawn considerable attention due to their natural abundance and low cost. In this work, nitrogen-doped porous carbons with high nitrogen content and large surface areas were designed and prepared from cottonseed hull and cattail. The two plant-based biomass compositions are similar, but the structures are very different, generating distinctly different property and performance of the prepared carbon materials. NRPC-112 has good electrochemical properties, while CN800 has good adsorption properties. By comparing the microstructure differences between the two starting materials, it was found that the structure of the raw materials would significantly affect the properties and performance of the materials. The work provided an important theoretical basis and reference for the selection of bio-resources for preparing carbon material. It is also important for choosing the appropriate synthesis method, process optimization, and application scenarios.

Experimental Study of Tensile and Flexural Strength of Cottonseed Hull Reinforced Epoxy Composites

In this study, the tensile and flexural strengths of cottonseed hull reinforced epoxy composites were investigated. Specimens were made using a stainless steel mold. A hand lay-up process was used to make the composite material, and three kinds of materials were made: unreinforced epoxy, raw cottonseed hull reinforced composite, and grinded cottonseed hull reinforced composite. The fiber content of all composites is 15 wt%. Tensile and flexural test were performed with universal testing machine. The result shown that Tensile and flexural strengths of grinded cottonseed hull reinforced composites were found to be the highest.

Effects of Licorice Extract Supplementation on Feed Intake, Digestion, Rumen Function, Blood Indices and Live Weight Gain of Karakul Sheep

This study was designed to investigate the effects of licorice extract supplemented to a cottonseed hull-based diet on rumen function, blood indices and growth of Karakul sheep. Twelve rumen-fistulated 1.5-year-old sheep were blocked in pairs by live weight. Sheep within pairs were randomly allocated to feed either on a cottonseed hull basal diet (control group) or on a basal diet containing 4.5% of licorice extract on dry matter (DM) basis (supplemented group). Sheep were housed individually and fed for 60 days, with a 15-day adaptation period and a 45-day measurement period. Feed intake and live weight gain were quantified. Rumen and blood samples were taken during the measurement period. The DM intake was lower for the supplemented group than for the control group. The mean ruminal concentrations of total volatile fatty acid (VFA) and acetate and the ratio of acetate to propionate were lower, while the levels of propionate and butyrate were higher for the supplemented group than for the control group. Average daily live weight gain, digestible energy intake, apparent nutrient digestibility and feed conversion efficiency did not differ between the two treatments. The serum concentrations of immunoglobulin A and G were 2.1 and 1.8 times greater, and total antioxidant and superoxide dismutase increased by 1.8 and 1.2 times in the supplemented group compared with the control group. These results indicated that licorice extract supplementation in the diet at 4.5% of DM had a limited impact on rumen function but improved blood immunoglobulin and anti-oxidative status of Karakul sheep, without impairment of feed conversion efficiency or live weight gain.