One of the areas of modern pharmaceutics is the creation of innovative medicinal products based on plant materials. Of particular interest in this regard is the wood of Siberian larch, from which arabinogalactan (AG) and dihydroquercetin (DHQ) are obtained. Arabinogalactan is a probiotic and has immunomodulatory properties, dihydroquercetin is a compound with high antioxidant activity. However, the dependence of the dynamics of arabinogalactan utilization by microorganisms simultaneously on the molecular weight of the polysaccharide and the presence of DHQ has been practically not studied, although these factors are important in the development and scaling of biotechnological processes. In this work, the dependence of the growth dynamics on a thioglycollate medium of Bifidobacterium bifidum on the molecular weight of the heteropolysaccharide and the presence of DHQ was studied in vitro. It was shown that the combined effect of these factors additively reduces the accumulation of bacterial biomass by 40% relative to pure low molecular weight (20 kDa) arabinogalactan. The share of the negative effect of DHQ on the growth rate of bifidobacteria was 20%. The dynamics of changes in the relative concentrations of carbohydrates during cultivation was also studied. Usually, chromatography with long and multi-stage sample preparation is used to identify polysaccharides. In this work, the rate of AG utilization was monitored using UV spectroscopy, because according to our data, arabinogalactan is an optically active compound with a maximum absorption at 288 nm. During the measurements, a reliable negative correlation was found between the dynamics of bacterial growth and the rate of arabinogalactan utilization. Within 24 hours, the concentration of low-molecular AG decreases to a minimum level even in the presence of dihydroquercetin. On a medium with high-molecular arabinogalactan and dihydroquercetin, the concentration of carbohydrates reaches a minimum only on the third day of cultivation, which, along with the lowest final biomass content, indicates a negative effect on bacterial growth of both the flavonoid and the degree of polymerization of heteropolysaccharide molecules. Thus, the level of AG polymerization and the degree of its purification from DHQ affect the growth of the bifidobacteria culture. The presence of flavonoid impurities inhibits the growth of microorganisms, because dihydroquercetin exhibits bactericidal activity, and the high degree of AG polymerization reduces the efficiency of polysaccharide utilization, probably due to steric hindrances for hydrolases that cleave the β 1-4 glycosidic bond.

Pristavka Alexey Alexandrovich, Candidate of Sciences (Biology), Associate Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: pristavk@gmail.com

Yurinova Galina Valerievna, Candidate of Sciences (Biology), Associate Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: yurinova@yandex.ru

Mikhailenko Valentina Lvovna, Candidate of Science (Chemistry), Associate Professor, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: mival63@gmail.com

Sigova Anna Alexandrovna, Undegraduate, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: sigovaann02@gmail.com

Orlova Anastasiya Alekseevna, Undegraduate, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: nastay.orlowa2002@yandex.ru

Salovarova Valentina Petrovna, Doctor of Sciences (Biology), Professor, Head of Department, Irkutsk State University, 1, K. Marx st., Irkutsk, 664003, Russian Federation, e-mail: vsalovarova@gmail.com

Babkin V.A. Ekstraktivnye veshchestva drevesiny listvennitsy: khimicheskii sostav, biologicheskaya aktivnost, perspektivy prakticheskogo ispolzovaniya [Extractive substances of larch wood: chemical composition, Biological activity and prospects for practical use]. Innovatika i ekspertiza [Innovation and Expertise], 2017, vol. 2, no. 20, pp. 210-224. (in Russian)

Yurinova G.V., Selivanova D.S., Pristavka A.A., Sukhov B.G., Pogodaeva N.N., Kuznetsov S.V., Popkova S. M., Dzhioev Y.P., Rakova E.B., Trofimov B.A. Vozmozhnosti ispol'zovaniya rastitelnogo polisakharida arabinogalaktana dlya kul'tivirovaniya bifidobakterii [Possibilities of using vegetable polysaccharide Arabinogalactan for cultivation of bifidobacteria]. Izvestiya vuzov. Prikladnaya himiya i biotekhnologiya [News of Universities. Applied Chemistry and Biotechnology], 2014, vol. 4, no. 9, pp. 90-93. (in Russian)

Dzhioev Yu.P., Yurinova G.V., Sukhov B.G., Popkova S.M. Ganenko T.V., Pogodaeva N.N., Vasilyeva D.K., Rakova E.B., Safronova L.A., Podgorskii V.S., Trofimov B.A. Gemitsellyulozy i ikh nanobiokompozity – perspektivnye nanostrukturirovannye sinbiotiki [Hemicellulozes and their nanobiocomposites – perspective nanostructured sinbiotics]. Acta Biomedica Scientifica, 2012, vol. 5, no. 87, pt. 1, pp. 210-212. (in Russian)

Kovalskaya G.N, Kolmakova E.S. Razrabotka sostava i tekhnologii polucheniya gelya na osnove nanobiokompozita digidrokvertsetina i arabinogalaktana dlya lecheniya khronicheskoi venoznoi nedostatochnosti [Development of the composition and technology of gel preparation based on the nanobiocomposite of dihydroquercetin and arabinogalactan for the treatment of chronic venous insufficiency]. Voprosy obespecheniya kachestva lekarstvennyh sredstv [Issues of quality assurance of medicines], 2023, vol. 3, no. 41, pp. 30-35. (in Russian)

Kovalskaya G.N., Kolmakova E.S., Nikiforov S.B., Lozovskaya E.A., Artemieva A.V. Nanobiokompozit na osnove digidrokvertsetina i arabinogalaktana v vide gelya dlya naruzhnogo primeneniya kak sredstvo dlya lecheniya khronicheskoi venoznoi nedostatochnosti v eksperimente [Nanоbiocomposite based on dihydroquercetin and arabinogalactan In the form of A gel for external use as a means for the treatment of chronic venous insufficiency in an experiment]. Acta biomedica scientifica, 2022, vol. 7, no. 4, pp. 212-218. https://doi.org/10.29413/ABS.2022-7.4.24 (in Russian)

Babkin V.A., Ivanova S.Z., Fedorova T.E., Medvedeva E.N., Malkov Yu.A., Ostrouhova L.A., Trofimova N.N., Ivanova N.V. Nauchnye osnovy tekhnologii kompleksnoi pererabotki biomassy listvennitsy [Scientific basis of the technology of complex processing of larch biomass]. Khimija rastitel'nogo syr'ja [Chemistry of Plant Raw Materials], 2007, no. 3, pp. 9-21. (in Russian)

Sukhov B.G., Pogodaeva N.N., Kuznetsov S.V., Kupriyanovich Y.N., Trofimov B.A., Yurinova G.V., Selivanova D.S., Pristavka A.A., Medvedeva P.A., Dzhioev Y.P., Popkova S.M., Rakova E.B. [Prebiotic effect of native noncovalent arabinogalactan – flavonoid conjugates on bifidobacteria]. Russ. Chem. Bull., 2014, vol. 63, no. 9, pp. 2189-2194.

Vityazeva S.A., Starovoitova Т.P., Dubrovina V.I. Sravnitelnaya kharakteristika immunnogo otveta makroorganizma pri peroralnom i parenteralnom vvedenii metallosoderzhashchego nanobiokompozita [Comparative characterization of the macroorganism immune response after peroral and parenteral introduction of metallic nanocomposite]. Acta biomedica scientifica, 2012, vol. 2, no. 84. pp.11-4117. (in Russian)

Andreani E.S., Karboune S., Liu L. Structural Characterization of Pectic Polysaccharides in the Cell Wall of Stevens Variety Cranberry Using Highly Specific Pectin-Hydrolyzing. Polymers, 2021, vol. 13, 1842. https://doi.org/10.3390/polym13111842

Çınar Acar B., Yüksekdağ Z. Beta-Glycosidase Activities of Lactobacillus spp. and Bifidobacterium spp. and The Effect of Different Physiological Conditions on Enzyme Activity. NESciences, 2023, vol. 8, no. 1, pp. 1-17. https://doi.org/10.28978/nesciences.1223571

Debelo H., Fiecke C., Terekhov A., Reuhs B., Hamaker B., Ferruzzi M.G. Compositional analysis of phytochemicals and polysaccharides from Senegalese plant ingredients: Adansonia digitata (baobab), Moringa oleifera (moringa) and Hibsicus sabdariffa (hibiscus). NFS Journal, 2023, vol. 32, 100144. https://doi.org/10.1016/j.nfs.2023.100144

Ghose T.K. Measurement of cellulase activity. Pure Appl. Chem., 1987, vol. 59, pp. 257-268.

Myers J.A., Curtis B.S., Curtis W.R. Improving accuracy of cell and chromophore concentration measurements using optical density. BMC Biophys., 2013, vol. 6, no. 4. https://doi.org/10.1186/2046-1682-6-4

Nguyen T.L.A, Bhattacharya D. Antimicrobial Activity of Quercetin: An Approach to Its Mechanistic Principle. Molecules, 2022, vol. 27, no. 8, 2494. https://doi.org/10.3390/molecules27082494

Harteminka R., Kok B.J., Weenk G.H., Rombouts F.M. Raffinose-Bifidobacterium (RB) agar, a new selective medium for bifidobacteria. J. Microbiol Methods, 1996, vol. 27, no. 1, pp. 33-43. https://doi.org/10.1016/0167-7012(96)00926-8

Brecker L., Wicklein D., Moll H., Fuchs E.C., Becker W.M., Petersen A. Structural and immunological properties of arabinogalactan polysaccharides from pollen of timothy grass (Phleum pratenseL.). Carbohydr. Res., 2005, vol. 340, no. 4, pp. 657-63. https://doi.org/10.1016/j.carres.2005.01.006