Study on Some Chemical Parameters and Essential Oil Compositions in Two Origanum Species Grown in Van Region, Turkey

Abstract

Primary and secondary metabolites, which are natural products produced by plants, are mainly used, either directly or indirectly, in industries. These are active substances, for example etheric oils (essential oils, essences), alkaloids, tannins, bitter substances, etc., that are predominantly involved in plant metabolism. They increase the body's defence system, support the functions of organs and accelerate healing. Thus, they have positive effects on the functions of certain tissues and organs. In this study, some bioactive and biochemical compounds, dry matter, total antioxidant activity, total flavonoid and total phenolic content, macro-micro and heavy metal content, essential oil yield and content in Origanum onites and Origanum dubium species were determined. It was found that total ash (10.61-12.03%), dry matter (38.24-43.47%), total antioxidant activity (121.41-162.17 mu mol TE g-1), total phenolic content (187.04-192.25 mg GAE g-1), total flavonoid content (10.01-17.57 mg QE 100 g-1), chlorophyll amount (23.26-23.30 dx) and NBI (the Nitrogen Balance Index) (13.90-28.23 dx) were higher in O. dubium than in O. onites. Yield of essential oil was determined between 3.130 and 3.240 in O. onites and O. dubium species, respectively. Carvacrol (78.24%), gamma-terpinene (6.650%) and cymene (3.950%) components were found to be dominant in the essential oil of O. onites. On the other hand, the main components of essential oil obtained from O. dubium species were carvacrol (22.01%), gamma-terpinene (23.55%), cis-sabinene hydrate (13.90%), terpinen-4-ol (8.500%), alpha-terpinene (4.94%), cymene (4.94%) and trans-sabinene hydrate (3.35%).