Relationship between volatile components of citrus fruit essential oils and antimicrobial action on Penicillium digitatum and Penicillium italicum

This study examined the effect of volatile components of citrus fruit essential oils on P. digitatum and P. italicum growth. The hydrodistilled essential oils of orange (Citrus sinensis cvv. “Washington navel”, “Sanguinello”, “Tarocco”, “Moro”, “Valencia late”, and “Ovale”), bitter (sour) orange (C. aurantium), mandarin (C. deliciosa cv. “Avana”), grapefruit (C. paradisi cvv. “Marsh seedless” and “Red Blush”), citrange (C. sinensis x Poncirus trifoliata cvv. “Carrizo” and “Troyer”), and lemon (C. limon cv. “Femminello”, collected in three periods), were characterized by a combination of GC and GC/MS analyses. The antifungal efficacy of the oils was then examined at progressively reduced rates. Findings showed a positive correlation between monoterpenes other than limonene and sesquiterpene content of the oils and the pathogen fungi inhibition. The best results were shown by the citrange oils, whose chemical composition is reported for the first time, and lemon. Furthermore P. digitatum was found to be more sensitive to the inhibitory action of the oils.