Phenolic profile, antioxidant and anticandidal activities of Inula oculus-christi L. from Turkey

The study aimed to determine the total phenol content of the extracts prepared with different solvents (70% methanol, ethyl acetate, 5% infusion) from the aerial parts of the I. oculus-christi, as well as to evaluate the antioxidant capacity and antimicrobial activity of the plant and to determine the main components responsible for the effect. The total phenolic content of the extracts prepared from the aerial parts of I. oculus-christi was calculated in gallic acid equivalents and the total phenolic content of the species was found to be in the range of 23.8-75.3 mg GAE/g. The highest total phenol content calculated as gallic acid equivalent was detected in the 5% infusion sample. The antioxidant activity of I. oculus-christi was also tested using DPPH' free radical scavenging in vitro assay (IC50: 0.092-1.03 mg/mL). The 5% infusion of the plant was shown to be the most effective extract in the antioxidant activity test performed using the DPPH' technique. The findings revealed that there is a correlation between total phenol content and antioxidant activity, as numerous research as suggested. By using the microdilution method, extracts from the aerial parts of I. oculus-christi were tested against Candida strains, and the MIC value for C. utilis was found to be 0.03 mg/mL in 5% infusion and ethyl acetate extracts. In terms of evaluating the biological effects obtained, the chemical composition of extracts was analyzed by HPLC-MS/MS, and the main components (5-caffeoylquinic acid, 1,5-dicaffeoylquinic acid, luteolin/kaempferol, apigenin, and rutin) were determined.