Phenolic Compounds of Origanum Sipyleum L. Extract, and Its Antioxidant and Antibacterial Activities

The flowers of Origanum sipyleum L., which is an endemic species in Turkey, are traditionally used as a beverage and medicinal tea. The extract was analyzed by reversed‐phase high‐performance liquid chromatography. The main phenolic compounds of O. sipyleum contained 6.81 ± 1.95, 3.94 ± 1.65, 6.78 ± 1.53, 6.71 ± 1.01, 4.95 ± 3.30, 870.22 ± 82.66, 19.47 ± 1.77 and 1017.33 ± 93.06 mg/100 g herb of apigenin, caffeic acid, carvacrol (phenolic monoterpene), hesperidin, naringenin, rosmarinic acid, rutin and vitexin, respectively. However, acecetin, apigenin 7‐glucoside, carnosic acid, eriodictyol, gallic acid, genistin, luteolin and naringin were not determined. In this study, the antioxidant and antimicrobial activities of O. sipyleum extract were determined, and their phenolics identified. Total phenolics, scavenging of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical and the antioxidant capacity by the formation of phosphomolybdenum complex of the extract were determined. The phenolic content was 226.66 ± 1.18 mg gallic acid equivalents/g in the dried extract. At 100‐ppm concentration, the DPPH radical scavenging activity of extract was 73.98 ± 2.66%. The antioxidant capacity of the extract was 335.33 ± 2.87 mg/g. This extract was investigated for its antibacterial activity by using agar diffusion method against 15 species of bacteria. Statistical differences within the bacteria were significant at P < 0.05. The extract was effective against all the bacteria tested, except for Yersinia enterocolitica. PRACTICAL APPLICATIONS Dietary phenolic compounds have generally been considered as non‐nutritive substances, and their possible benefit to human health has recently been considered. There is now much interest in the biological effects of phenolic compounds since evidence was found that diets rich in fruit, vegetables, spice and herbs appear to protect against cardiovascular disease, some forms of cancer and degenerative health factors associated with aging. Nowadays, the consumption of foods rich in phytochemicals like herbs and spices is regarded as important and good for health. Phytochemicals are not absolutely required to be part of the diet, but may confer health benefits such as antioxidant and antimicrobial activities. The bioactivity of O. sipyleum identified in this study has great potential for human and animal health because of its broad‐range antibacterial activity against some bacteria and antioxidant capacity.