Schizochytrium sp.'den ekstrakte edilen lipitlerin antimikrobiyal ve anti-biyofilm aktiviteleri. S31 mikroalgi

Biotechnology has been developing tools and procedures for the benefit of living things for many years. In most of these studies, the production of essential metabolic compounds is prioritized for human health. One of the crucial substances for human health that has gained popularity recently is omega-3 fatty acids. Alternative sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been searched since fish oils, the main commercial sources of omega-3 fatty acids, have heavy metal content, especially mercury, limited availability, and an unpleasant odor. Schizochytrium sp. S31 is a microalga with a high concentration of polyunsaturated fatty acids, particularly DHA. Because of its high DHA content and low heavy metal levels, heterotrophic cultivation of Schizochytrium sp. S31 provides an excellent opportunity to provide alternative omega-3 sources. It also contains a variety of bioactive substances that can be utilized as medicinal raw materials, food additives, animal feed, biodiesel and antimicrobial agents. In this study, optimum conditions were applied to cultivate Schizochytrium sp. S31 heterotrophically and the nutritional composition of the dry biomass were analysed. According to the results, 45% protein, 5% total fat and 37% carbohydrate were obtained. Downstream processes, including cell lysis and lipid extraction, were adjusted in order to increase overall lipid content of Schizochytrium sp. S31. Five distinct solvent mixtures—hexane, hexane/ethanol (2:1), ethanol, methanol, and hexane/methanol (2:1)—as well as two different cell lysis techniques —mortar and pestle and ultrasonication—were examined and compared. Based on the results of cell lysis and lipid extraction, ultrasonication of hexane /methanol (2:1) enhanced the total lipid yields to 34% with a transparent appearance. According to the GCMS analysis results, 10.4% DHA and 16.11% EPA fatty acids were obtained. Total Omega-3 Fatty Acids and Total Omega-3 + Omega-6 Fatty Acids ratio were calculated as 27.42% and 32.15% respectively. The antibacterial effects of Schizochytrium sp. S31 oil samples were also investigated on Gram-negative pathogens, Pseudomonas aeruginosa, Escherichia coli 35218 and Klebsiella pneumonia, which cause many different human infections, as well as the Gram-positive pathogen Streptococcus mutans. At the same time, their effects on biofilm formation in Pseudomonas aeruginosa, Escherichia coli 35218 bacteria were investigated. The Schizochytrium sp. S31 oil sample was found to have anti-pathogenic activity on pathogenic bacteria of Pseudomonas aeruginosa, Escherichia coli 35218, Klebsiella pneumonia and Streptococcus mutans. The surface adhesion ability and biofilm formation capability of P. aeruginosa and Escherichia coli 35218 strain, which are widely employed as model bacteria in biofilm research, were dramatically inhibited in the presence of a Schizochytrium sp. S31 oil sample.