Variation in the components and antioxidant activity of Citrus medica L. var. sarcodactylis essential oils at different stages of maturity

Finger citron (Citrus medica L. var. sarcodactylis) (FC) fruits, widely cultivated in the southern provinces of China, are commonly used as a traditional Chinese medicinal material. The study was conducted to determine variations of essential oils (E0s) yield, composition and antioxidant activities during three maturation stages in FC fruits. EOs yields showed marked increase during maturation process. EOs composition obtained by hydrodistillation was characterized by GC-MS. In total, 27, 22 and 22 components were identified and quantified in immature, intermediate and mature stages, representing 99.56%, 99.38% and 99.54% of the total detected constituents, respectively. The content of limonene, the main component, varied between 32.07% and 36.37%, and the variation was statistically significant during maturation stages. The contents of some components, particularly alpha-thujone, 3-carene, alpha-pinene, beta-pinene and gamma-terpinene, varied significantly during maturation stages. Increasing maturity at harvest decreased antioxidant activities of finger citron EOs. Additionally, accumulation of monoterpene hydrocarbons and ketones was observed during maturation process. (C) 2013 Elsevier B.V. All rights reserved.