COMPARATIVE ANALYSIS OF METHODS OF ISOLATION OF POSTBIOTICS AND DETERMINATION OF THE YIELD OF DRUGS FROM MICROORGANISMS

The article presents the results of a study aimed at a comparative analysis of postbiotic isolation methods and determining the yield and antioxidant activity of preparations obtained from Lacticaseibacillus sp., Leuconostoc sp., and Saccharomyces sp. strains isolated from traditional fermented products (shubat, sauerkraut, and kumiss). Based on an analysis of literary sources, three methods were selected for experimental studies: thermal cell inactivation, ethanol precipitation, and ultrafiltration, characterized by technological simplicity, cost-effectiveness, and the ability to preserve biologically active components. The yield of postbiotics was determined gravimetrically, antioxidant activity by DPPH and ABTS tests, and microbiological safety by the absence of viable cell growth. It was found that the thermal method provides the highest dry matter yield (90-92%), high antioxidant activity (86-89%), and complete microbiological safety compared to other methods. A gentle inactivation regime (70°C for 30 min) preserved functional metabolites without destroying low-molecular-weight antioxidants and exopolysaccharides involved in redox processes. The highest activity values were obtained for the Leuconostoc sp. strain, which is due to the presence of an exopolysaccharide matrix stabilizing the active compounds. The obtained results confirm the feasibility of thermal inactivation as an effective and affordable method for isolating postbiotics for the development of functional dairy products and the expansion of biotechnological approaches in the food industry.

1. Begunova A.V. Otsenka potentsiala propionovokislykh bakterii dlya polucheniya postbiotikov / A.V. Begunova, N.A. Zhizhin // Khranenie i pererabotka sel'khozsyr'ya. – 2022. – № 4. – S.102-112. (In Russian).

2. Rozhkova I.V. Postbiotiki kak potentsial'nye komponenty kislomolochnykh produktov s funktsional'nymi svoistvami / I.V. Rozhkova, V.A. Leonova, A.V. Begunova // Molochnaya promyshlennost'. – 2022. – № 3. – S.16-18. (In Russian).

3. Kolokolova A.YU. Izuchenie izmeneniya organolepticheskogo profilya kislomolochnoi produktsii s dobavleniem postbiotika / A.YU. Kolokolova, I.V. Rozhkova, V.A. Leonova // Pishchevaya promyshlennost'. – 2024. – № 6. – S. 52-55. (In Russian).

4. Sazanova S.N. Poluchenie morozhenogo s probiotikami i postbiotikami SacchromycesBoulardii / S.N. Sazanova, S.A. Ryabtseva, S.S. Avanesyan // Izvestiya vysshikh uchebnykh zavedenii. Pishchevaya tekhnologiya. – 2024. – № 2-3(396). – S. 48-54. (In Russian).

5. Paraprobiotics and postbiotics: concepts and potential applications in dairy products / C.P. Barros et al // Current Opinion in Food Science. – 2020. – Vol. 32. https://doi.org/10.1016/j.cofs.2019.12.003. (In Russian).

6. Develompment and properties of functional yoghurt enriched with postbiotic produced by yoghurt cultures using cheese whey and skim milk / S. Sadighbathi et al // Frontiers. – 2023. – Vol. 14. https://doi.org/10.3389/fmicb.2023.1276268. (In English).

7. Păcularu-Burada B. Freeze-dried biotics based on Lactiplantibacillus plantarum with functional properties / B. Păcularu-Burada, M.M. Stanciu, M.A. Vasile // Food Science and Technology (LWT). – 2024. – № 203(12). https://doi.org/10.1016/j.lwt.2024.116339. (In English).

8. Abitha Eswari U. Thermal methods of postbiotics preparation / U. Abitha Eswari, K. Ramesh, T. Rajasekar // In: Postbiotics: Methods and Protocols in Food Science. – New York: Humana Press, 2024. – 424 p. (In English).

9. Paul Beulah B.F. Preparation of postbiotics from Bacillus spp / B.F. Paul Beulah, T. Rajasekar // In: Postbiotics: Methods and Protocols in Food Science. New York: Humana Press, 2024. – 424 p. (In English).

10. The Effects of Substrates and Sonication Methods on the Antioxidant Activity of Kefir Postbiotics / G. Chávez-Alzaga et all // Fermentation. – 2024. – Vol. (9). https://doi.org/10.3390/fermentation10090492. (In English).

11. Duarte M. Current postbiotics in the cosmetic market: perspectives for food applications / M. Duarte, G. Vinderola, E. Salvucci // Applied Microbiology and Biotechnology. – 2022. – Vol. 106(12). – R. 5879-5891. (In English).

12. Cimini D. Optimization of growth and postbiotic production by Levilactobacillus brevis SP48 / D. Cimini, G. Mezzapesa, S. Fedi / /Frontiers in Bioengineering and Biotechnology. – 2022. – Vol. 10. https://doi.org/10.3389/fbioe.2022.1007004. (In English).

13. Leonova V.A. Metody polucheniya postbiotikov / V.A. Leonova, I.V. Rozhkova // Molochnaya promyshlennost'. – 2022. – № 4. – S. 24-25. (In Russian).