Antifungal efficacy and chemical composition of essential oil from the Egyptian sweet orange peel (Citrus sinensis, L)

Fruits and vegetables wastes and their by-products are formed in great amounts during industrial processing and hence represent a serious problem, as they exert harmful impact on environment. So they need to be managed or they can be utilized. The present study was conducted to investigate in vitro antifungal activities of the essential oil of the Egyptian sweet orange peel. The sample of fresh orange peels was subjected to hydro-distillation for 3 h using a Clevenger-type apparatus and distillates of essential oil was dried over anhydrous sodium sulfate, filtered and stored at -4°C until analyzed. Gas chromatography (GC) and Gas chromatography-mass spectrometry (GC-MS) were used to determine the aromatic compounds of peel oil of sweet orange fruit in this study. The identification of the oil constituents was based on the comparison of their retention indices relative to (C6-C24) n-alkanes either with those of published data or with authentic compounds. And also identified using their MS data compared to those from the NIST mass spectral library and published mass spectra. Antifungal activity was carried out by measuring changes in mold growth, PH, and aflatoxin(s) contents in Yeast Extract Sucrose broth media (YES). Results showed that total of 24 compounds were identified and the major components were limonene (86.75%), linalool (1.96%), ?-pinene (1.63%), trance-limonene oxide (1.39%), and ?-terpinene (1.03%). The volatile oil showed antifungal activities against Aspergillus flavus, and Aspergillus paraciticus under in vitro condition. In conclusion, the potential antifungal activity of essential oil present in the Egyptian sweet orange peel could be applied as food preservative.