PHENOLIC COMPOUNDS OF CHLORELLA VULGARIS AS ANTIMICROBIAL AGENTS

Abstract

Among the primary and secondary metabolites of microalgae, there are compounds that are potential antimicrobial substances: polyphenols, carotenoids, saponins, tannins, etc. It is interesting that these BARs can be both localized in algomass and accumulate in the culture liquid during the cultivation of algae. In the study, an algologically pure culture of Ch. vulgaris, maintained in the NN collection of the Institute of Biology, Chemistry and Bioresources of the ChN University. Algae were grown on the classic Tamiya medium at a temperature of 24 ± 2 °C for 14 days. Hydroxycinnamic acids, flavonoids and polyphenolic compounds were detected in the culture fluid and alcoholic extract of biomass. The alcoholic extract of Chlorella vulgaris, in contrast to the culture liquid, had a higher amount of polyphenols, hydroxycinnamic acids, azulenes and different classes of flavonoids. Spectral analysis of alcohol extracts from algal biomass and culture liquid confirmed the presence of flavonoids, phenolic acids and coumarins. The following microorganism test cultures were used: Bacillus subtilis and Sarcina flava (Gr+), Microcystis pul-verea (Gr-), Rhodotorula rubra (eukaryote). One-day test cultures of microorganisms were standardized according to McFarland to 0.5. The study of antimicrobial activity was carried out by the method of diffusion in agar: 100 μl of the test culture of microorganisms was sown with a lawn on a solid medium of MPA, 25 μl of culture liquid Chh was introduced into the wells. vulgaris. On the third day, the result of cultivation was evaluated. It was noted that the sensitivity of the test cultures to the culture liquid and biomass extract of Ch. vulgaris depends on the structure of the cell wall of microorganisms. Yes, gram-positive microorganisms and yeast are more sensitive. For them, the diameter of growth retardation zones is determined in the range from 20 to 25 mm. The most sensitive were Sarcina flava and Rhodotorula rubra. At the same time, gram-negative microorganisms were not sensitive to the culture liquid and biomass extract of Ch. vulgaris, the diameter of the zone of growth retardation did not exceed 5 mm. The revealed antimicrobial activity of green algae Ch. vulgaris is associated with the presence of polyphenolic compounds in the biomass. Therefore, culture fluid and biomass of Ch. vulgaris can be recommended for use in feed as a natural antifungal and antibacterial component.