Biological activity and fatty acid composition of Caesar's mushroom

Context: Due to its pleasant aroma and flavor, Amanita caesarea (Scop.) Pers. (Amanitaceae) has been a famous macrofungus since ancient times. This species is also well known in Turkey where people consume it extensively. Objective: Evaluation of the medicinal importance of A. caesarea for human health. Materials and methods: Antioxidant capacity of A. caesarea was studied using the methods of a scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radicals, beta-carotene-linoleic acid assay, reducing power and estimation of phenolics. Chloroform, acetone and methanol extracts of A. caesarea were tested for their antimicrobial activity against four Gram-positive bacteria, five Gram-negative bacteria and one yeast by applying a micro dilution method. The fatty acids were estimated via the method of gas chromatography analysis. Results: The scavenging effect of A. caesarea on DPPH radicals was measured as 40.91% at 0.5 mg/mL concentration, and its reducing power was 0.451 mg/mL at 1.2 mg/mL concentration. The phenolics found were catechin (32.5 mg/g), ferulic acid (7 mg/g), p-coumaric acid (6 mg/g) and cinnamic acid (6.2 mg/g). The highest minimum inhibitory concentration observed against the test microorganisms were with the acetone extract (4.8 mg/mL concentration) against Candida albicans. Thirty-seven different fatty acids were determined from A. caesarea, and oleic acid (58%) was the dominant component. Discussion and conclusion: Amanita caesarea had a high-antioxidant and -antimicrobial activity, and it also had important essential fatty acids required for human health. According to the results, this mushroom can be recommended as a major source of natural food.