Crop Residue Based Complete Feed for Enhancing Livestock Performance- A Review

The estimated projected data regarding demand and supply of feed and fodder shows13.20% and 18.43% deficit between demand and supply of dry and green fodder to livestock, respectively. Shortage of land for cultivation of fodders and increased human as well as livestock population has led to heavy competition for food grains that necessitates using the crop residues for the feeding of livestock. These crop residues are rich in fibre and low in other nutrients; they also have low palatability and digestibility. The best way to efficiently utilize the crop residues is to prepare complete feeds from pretreated crop residues + concentrates mixture. Pretreatment of crop residues increases digestibility by increasing rate of delignification, increasing enzymatic hydrolysis of cellulose, hemicelluloses and thus increasing the glucose yield. The complete feed is a quantitative mixture of all dietary ingredients to provide the specific nutrient requirement for various physiological functions of livestock. Crop residue-based complete feed could be prepared in mash, block and pellet (Expander and extruder) form. In this system, all feed ingredients including roughages are proportioned, processed and mixed into a uniform blend. Different researchers undertook feeding trials of complete animal feed and conventional animal feed and reported better performance in terms of weight gain, milk yield and reproductive performance on feeding complete feed pellets or complete feed blocks to ruminants as compared to conventional ration. In conclusion, crop residue based complete feed could improve ruminant performance and reduces cost of feeding per kg gain or yield and thereby improving livestock based rural economy in developing countries like India.

Bleaching of Microcrystalline Cellulose Produced by Gas-Phase Hydrolysis

One of the main consumers of microcrystalline cellulose (MCC) is the pharmaceutical industry, where MCC is used as a binder and filler in direct compression of tablets. MCC is produced by acidic hydrolysis of cellulose, which usually results in a decrease in whiteness. This is due to the destruction of sugars formed during hydrolysis and the subsequent formation of colored products. The composition and properties of these products depend on the method of hydrolysis, acid concentration, temperature, and process duration. One of the most promising methods for producing MCC is gas-phase hydrolysis of cellulose with hydrogen chloride gas-air mixtures. The method has a high rate of hydrolysis, low reagent and energy consumption. The requirements of the pharmaceutical industry determine the need to produce MCC with high whiteness. The research purpose is to select bleaching modes for MCC using sodium hypochlorite and hydrogen peroxide as bleaching agents. MCC produced by gas-phase hydrolysis of bleached wood pulp was used during the study. The whiteness and intensity of the yellow tint of MCC in the bleaching process were determined by digital colorimetry on a flatbed scanner. The paper shows that sodium hypochlorite and hydrogen peroxide allow achieving the whiteness not less than 90 % and the intensity of the yellow tint not more than 3 standard units. High-quality bleaching can be carried out even for MCC samples with an initial whiteness of about 40 %. The most effective bleaching agent is sodium hypochlorite when the pH of the bleaching solution is 2–3. Hydrogen peroxide also provides high whiteness of MCC at pH of 10–11. However, the consumption of active oxygen (AO) for bleaching is more than three times higher in comparison with the consumption of active chlorine (ACh). It was found that the dyes of MCC produced by gas-phase hydrolysis consist of two chromophore groups that decolorize at different rates. The easily oxidized group of components makes up about 90 % of the total amount of dyes, and the resistant to oxidation components make up about 10 % and determine the intensity of the yellow tint of MCC. The modes of bleaching MCC with sodium hypochlorite and hydrogen peroxide to product samples with whiteness comparable to that of imported samples were determined. For citation: Sizov A.I., Pimenov S.D., Stroiteleva A.D., Stroiteleva K.D. Bleaching of Microcrystalline Cellulose Produced by Gas-Phase Hydrolysis. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 173–183. DOI: 10.37482/0536-1036-2021-6-173-183

The Effect of Dicarboxylic Acid Catalyst Structure on Hydrolysis of Cellulose Model Compound D-Cellobiose in Water

Background: Polycarboxylic acids are of interest as simple mimics for cellulase enzyme catalyzed depolymerization of cellulose. In this study, DFT calculations were used to investigate the effect of structure on dicarboxylic acid organo-catalyzed hydrolysis of cellulose model compound D-cellobiose to D-glucose. Methods: Binding energy of the complex formed between D-cellobiose and acid (Ebind), as well as glycosidic oxygen to dicarboxylic acid closest acidic H distance were studied as key parameters affecting the turn over frequency of hydrolysis in water. Result: α-D-cellobiose - dicarboxylic acid catalyst down face approach showed high Ebind values for five of the six acids studied; indicating the favorability of down face approach. Maleic, cis-1,2-cyclohexane dicarboxylic, and phthalic acids with the highest catalytic activities showed glycosidic oxygen to dicarboxylic acid acidic H distances 3.5-3.6 Å in the preferred configuration. Conclusion: The high catalytic activities of these acids may be due to the rigid structure, where acid groups are held in a fixed geometry.

Enhanced Enzymatic Hydrolysis of Cellulose From Substrate and Indole-3-Acetic Acid Content—During the Fruiting Body Differentiation Stage by Sodium Acetate Addition

Volvariella volvacea, with high commercial, nutritional and medicinal value, is widely cultivated in tropical and subtropical regions. The effects of supplementation on mushroom yield has been studied. We showed that the optimal application of sodium acetate (NaAc) was spray application of a 0.08% concentration during the substrate mixing stage which could increase yields by up to 89.16% and enhance the enzymatic hydrolysis of cellulose and hemicellulose from the substrate. For most enzymes tested maximum activity occurred during the fruiting body growth and development stage, which led to degradation of the substrate, increasing the available nutrients for mycelial propagation and fruiting body growth and development. Meanwhile, NaAc also significantly increased the indole-3-acetic acid (IAA) content in the early fruiting body development stage of V. volvacea, It was observed that IAA promotes not only plant primordium differentiation; but also the primordium differentiation of edible fungi. Furthermore, treatments with three acetate salts had an increase of yield by 30.22% on average. The mechanisms by which NaAc application may improve the yield of V. volvacea are discussed.

Synthesis, Characterization and Application of Polypyrrole Functionalized Nanocellulose for the Removal of Cr(VI) from Aqueous Solution

Heavy metals are toxic substances that pose a real danger to humans and organisms, even at low concentration. Therefore, there is an urgent need to remove heavy metals. Herein, the nanocellulose (NC) was synthesized by the hydrolysis of cellulose using sulfuric acid, and then functionalized using polypyrrole (ppy) through a polymerization reaction to produce polypyrrole/nanocellulose (ppy/NC) nanocomposite. The synthesized nanocomposite was characterized using familiar techniques including XRD, FT-IR, SEM, TEM, and TGA. The obtained results showed a well-constructed nanocomposite with excellent thermal stability in the nano-sized scale. The adsorption experiments showed that the ppy/NC nanocomposite was able to adsorb hexavalent chromium (Cr(VI)). The optimum pH for the removal of the heavy metal was pH 2. The interfering ions showed minor effect on the adsorption of Cr(VI) resulted from the competition between ions for the adsorption sites. The adsorption kinetics were studied using pseudo 1st order and pseudo 2nd order models indicating that the pseudo second order model showed the best fit to the experimental data, signifying that the adsorption process is controlled by the chemisorption mechanism. Additionally, the nanocomposite showed a maximum adsorption capacity of 560 mg/g according to Langmuir isotherm. The study of the removal mechanism showed that Cr(VI) ions were removed via the reduction of high toxic Cr(VI) to lower toxic Cr(III) and the electrostatic attraction between protonated ppy and Cr(VI). Interestingly, the ppy/NC nanocomposite was reused for Cr(VI) uptake up to six cycles showing excellent regeneration results. Subsequently, Cr(VI) ions can be effectively removed from aqueous solution using the synthesized nanocomposite as reusable and cost-effective adsorbent.

Preparation of a Cellulase-imitated Solid Acid Catalyst With High Acid Density and Its Evaluation for Hydrolysis of Cellulose

In this paper, tannic acid, a polyphenolic substance rich in plants, is modified by the glutamic acid and cross-linked with formaldehyde to prepare a high acid density tannin-glutamate acid resin-based imitation enzyme solid acid catalyst (T-Glu-R), which is completely different from traditionally carbon-based solid acid synthesized by concentrated sulfuric acid and carbonized matter. The solid acid catalyst was characterized by Fourier transform infrared spectroscopy, scanning electron microscope, thermogravimetry, and X-ray photoelectron spectroscopy. The catalytic activity and cycle performance of T-Glu-R in the cellulose hydrolysis reaction were evaluated. The results show that the acid density of T-Glu-R reached 7.28 mmol/g, which is much higher than that of the highest acid density of carbon-based solid acid. Microcrystalline cellulose was hydrolyzed in distilled water at 180 °C for 2 h, the yield of total reducing sugars reached 72.15%. After four cycles of hydrolysis, the yield was only reduced by 4.32%, showing excellent cycle performance and stability. The study provides a new strategy with the synthesis of solid acid catalyst for hydrolysis of cellulose converted into platform compounds without concentrated sulfuric acid.