Antifungal potential of essential oils from two varieties of Citrus sinensis (lima orange and bahia navel orange) in postharvest control of Rhizopus stolonifer (Ehrenb.: Fr.) Vuill.

Brazil, the world's largest citros producer, yields around 19 million tons per year and exports most part of its production as orange juice. Essential oils (EOs) extracted from leaves, fruit and flowers of many species of the genus Citrus have been widely used as the result of their promising bioactivities. The fungus Rhizopus stolonifer (Ehrenb.) Vuill., an agent which causes soft rot in fruit, has been considered one of the main factors that cause postharvest diseases, thus, leading to major economic losses in agribusiness. This research aimed at evaluating the chemical composition and in vitro antifungal effect of EOs from two varieties of fresh Citrus sinensis (lima orange and bahia navel orange) peel on mycelial growth of R. stolonifer. EOs were obtained by hydrodistillation, which was carried out by a Clevenger-type apparatus, while their chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Limonene was the major monoterpene identified in EOs from lima orange (95.2%) and bahia navel orange (93.2%) peel. EOs from lima orange and bahia navel orange inhibited 91.95% and 80.05% mycelial growth of R. stolonifer, respectively, at the highest dose under evaluation (100 mu L). This study revealed the biotechnological potential of EOs extracted from fruit peel of two varieties of citros which may applied to biofilm preparation, so as to coat and preserve different types of fruit.