In Vitro Determination of Nitric Oxide Synthase Inhibition, Antioxidant Capacity and Phenolic Content of Various Natural Products (Bee and Herbal Products)

Abstract It is obvious that the oxidation process is an undeniable fact and when it comes to aging, one of the first solutions that come to mind is natural products. When it comes to natural products, both plants and bee products play an important, almost combative role against oxidation. For this purpose, natural products of both plant and animal origin were considered together in our study: Linden, green tea, aronia, wild grapes, myrtle, blueberries and basil, honey, pollen and propolis. Total phenolic content values of the extracts ranged between 49.28 and 3859.06 mg gallic acid equivalent/100 g, and propolis, green tea, chestnut flower and aronia samples were found to have the highest values. When looking at the NOS inhibition potential, it was determined that propolis, pollen and aronia samples had the highest percentage inhibition values of 98.11, 92.29, 83.44, respectively. Antioxidant activities of methanolic extracts were investigated using iron(III) reducing/antioxidant capacity (FRAP), 2,2‐Diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity test and NOS inhibition tests. The phenolic composition of methanolic extracts was tested using the RP‐HPLC‐UV (high‐performance liquid chromatographic method with ultraviolet) method with 19 phenolic standards.