Kazakhstan is a major producer of grain and leguminous crops. At the same time, grain wastes make up to 75% of the mass of raw materials, the main part of which is lignocellulosic wastes and remains unused from 30% to 50% of raw materials. Lignocellulosic raw materials can be used for the production of various value-added products such as biofuels, animal feed, chemicals, enzymes, etc. Wheat straw and bran, rice husks, corn cobs, etc. contain lignocellulose and are potential raw materials for industrial use. The processing of lignocellulosic waste not only solves the problem of environmentally friendly waste disposal, but also provides additional income to farms and creates jobs. Wheat bran and straw are excellent substrates for the cultivation of industrially important bacteria and fungi, as well as for the production of feed enzymes. Currently, there are ample ways to add value and utilize lignocellulosic raw materials for industrial purposes, such as the production of xylooligosaccharides, xylitol, and xylose.

Relevance

Xylooligosaccharides (XOs) are oligomers of sugars consisting of xylose links and are non-digestible food ingredients. Xylooligosaccharides have a prebiotic effect when consumed in food, selectively stimulate the growth of bifidobacteria and lactobacilli, thereby having a positive effect on human and animal health.

  Scientific novelty of the project consists in studying and obtaining xylooligosaccharides with different degrees of polymerization in order to study their prebiotic properties for use in animal husbandry. Practical significance of the project is the development of technology for processing lignocellulosic raw materials (straw, wheat bran) into functional foods for use in agriculture.

Objective

Study and obtain xylooligosaccharides by enzymatic hydrolysis of lignocellulosic raw materials (wheat straw and bran) for their use as functional foods.

Expected results

Physical and chemical pretreatment of lignocellulosic raw materials (straw, wheat bran) will be carried out. Enzymatic hydrolysis of lignocellulosic raw materials (straw, wheat bran) using xylanase will be carried out. Xylooligosaccharide fractions will be isolated, obtained and purified. The prebiotic and antibacterial activity of the obtained xylooligosaccharide fractions will be studied. The stability of xylooligosaccharides in the gastrointestinal tract with preservation of prebiotic properties will be determined. The obtained xylooligosaccharides can be used as prebiotics in animal husbandry. A technology for processing lignocellulose raw materials will be developed in order to obtain valuable products for use in agriculture.

Principal investigator

Kiribayeva A.K. H-index – 5; ResearcherID N-6774-2017, ORCID: 0000-0002-8293-2340, Scopus Author ID: 57215499873.

Members of the research group

Shamsiyeva Yu. – junior researcher, master, ResearcherID: AFX-3509-2022 ORCID: 0000-0002-3136-6000

Yakupov B. – laboratory assistant, 2nd year master’s student

Abdishov D. – laboratory assistant, 4th year undergraduate student     

Publications and security documents of the project manager and members of the research group

1. Assel Kiribayeva, Dmitriy Silayev, Zhiger Akishev, Kairat Baltin, Saniya Aktayeva, Yerlan Ramankulov, Bekbolat Khassenov. An impact of N-glycosylation on biochemical properties of a recombinant α-amylase from Bacillus licheniformis // Heliyon. 2024 Mar 13;10(6):e28064. doi: 10.1016/j.heliyon.2024.e28064. Impact Factor 3.4. Cite Score 5.6, Percentile 86.
2. Kiribayeva A., Mukanov B., Silayev D., Akishev Zh., Ramankulov Ye., Khassenov B. Cloning, expression, and characterization of a recombinant xylanase from Bacillus sonorensis T6 // PLoS One. 2022. Vol.17(3). e0202232. https://doi.org/10.1371/journal.pone.0202232. Q2, Impact Factor 4.069, Cite Score 5.5, Percentile 87.
3. Matta E., Kiribayeva A., Khassenov B., Matkarimov B., Ishchenko A. Insight into DNA substrate specificity of PARP1-catalysed DNA poly(ADP-ribosyl)ation // Scientific Reports. 2020. Vol.10(1), 3699. pp.1-11. https://doi.org/10.1038/s41598-020-60631-0. Q2, Impact Factor 5.516, Cite Score 7.0, Percentile 91.
4. Kiribayeva A., Silayev D., Abdullayeva A., Shamsiyeva Yu., Ramankulov Ye., Khassenov B. Hydrolysis of plant biomass using recombinant alpha-amylase from Bacillus licheniformis and xylanase from Bacillus sonorensis // Eurasian Journal of Applied Biotechnology, 2022. No. 4. P.31-39 doi: 10.11134/btp.4.2022.4 (РИНЦ-0,117).
5. Kiribayeva A., Silayev D., Tursunbekova A., Ramankulov Ye., Khassenov B. Cloning, purification and study of the biochemical properties of α-amylase from Bacillus licheniformis T5 strain // Вестник науки Казахского агротехнического университета им. С.Сейфуллина (междисциплинарный). – 2022 – №1 (112). – Р. 181-189. doi.org/10.51452/kazatu.2022.1(112).942

Results achieved

2024

The optimal conditions for pre-treatment of lignocellulosic raw materials using a base of 18.5% aqueous ammonia solution were determined: incubation of the reaction mixture for 14 hours at a temperature of 70°C, continuous stirring at 200 rpm. After that, filtration, washing with distilled water and drying at room temperature, then at 90°C were carried out. The physicochemical parameters of enzymatic hydrolysis of lignocellulosic raw materials using xylanase were optimized: temperature, pH, time and enzyme concentration. The optimal temperature was 40°C, pH – 7.0, time – 48 hours, xylanase concentration – 715 units/ml.