A new terpenoid from Olea europaea L. leaves and potential aptitude of different leaf extracts as anti-inflammatory agents

Background The olive tree (Olea europaea L.) has played a significant role in medical history, being used to relieve a wide range of illnesses in traditional medicine. The value of olive leaves came from their medicinal and nutritional properties. In recent times, it has been proven that there is a potential role of leaves in cancer prevention and inflammatory illnesses. Objective The purpose of this study was to look at the chemical makeup of methylene chloride fraction and also to evaluate the chemopreventive properties and the anti-inflammatory activity of different olive leave fractions using hepa1c1c7 cells and RAW264.7 macrophages activated by lipopolysaccharides, respectively. Materials and methods Air-dried powdered olive leaves were defatted with hexane, and the marc was then soaked in 80% methanol and successively extracted with CH2Cl2, EtOAc, and n-BuOH. Phytochemical investigation of CH2Cl2 fraction was done. The chemopreventive effect was determined in vitro using a hepa1c1c7 human carcinoma cell line, and the anti-inflammatory was carried out using RAW264.7 macrophages. Results and conclusion One novel compound, identified and given the name oleuropeinone (1), was obtained together with two known compounds, blumenol A (2) and megaritolactonol (3). Spectroscopic data such as 1H and 13C NMR were used to identify their chemical structures. The CH2Cl2 fraction is the most effective fraction to inhibit inflammatory markers inducible nitric oxide synthase and COX-2 protein expression in RAW264.7 macrophages. Moreover, it has a potent effect in inducing the chemopreventive marker NQO1 protein expression.