In vitro antioxidant and antibacterial activities of phenolic and alkaloid extracts of Laurus nobilis

Abstract

Laurus nobilis one of medicinal and aromatic plant endemic to the Mediter-ranean region. It is highly appreciated for the condiment benefits of its leaves. Due to its richness in bioactive compounds, the leaves are also used in traditional therapy to treat several infectious diseases. Phenolic com-pounds and alkaloids are particularly important because they are used in many pharmaceutical, food supplement, and cosmetic fields. The presence of phenolic compounds and alkaloids in L. nobilis leaves attracted our atten-tion due to their various functions such as antioxidant capacity and antibac-terial properties. The main objective of this study was to determine antioxi-dant and antibacterial activities of phenolic and alkaloid extracts of L. nobilis. The quantification of antioxidant substances allowed obtaining phenolic compounds content of 86.46 EAG mg/g and a total alkaloids yield of 700 μg/g. The results of antioxidant activity show that, although the alkaloid concen-trations are low, their antioxidant power is higher than phenolic compounds. The results of antibacterial activity of L. nobilis extracts revealed that the highest inhibition was recorded for alkaloid extract against staphylococcal strains responsible for food poisoning. However, L. nobilis phenolic com-pounds showed better activity against phytopathogenic strains associated particularly with potato rot.