Corylus avellana is a plant native to Europe and western Asia, generally cultivated for its nuts: the hazelnut. production. Hazelnuts are commercialized mainly for the food industry in many forms, but hazelnut oil is also used in cosmetics for its astringent and emollient properties. Hazelnuts are rich sources of α tocopherol, monounsaturated fatty acids (especially oleic acid), and phytosterols (especially β-sitosterol). A study demonstrated that the extracts of hazelnut kernel and hazelnut by products exhibit anti-oxidant activities. Phenolic acids, including gallic acid, caffeic acid, p-coumaric acid, ferulic acid, and sinapic acid, were identified from those extracts. Another study showed hazelnut extracts have anti-microbial activity against gram-positive bacteria, including Bacillus cereus, B. subtilis, and Staphylococcus aureus.