An Attempt of Postharvest Orange Fruit Rot Control Using Essential Oils from Mediterranean Plants Ippolito Camele, 1 Vincenzo De Feo, 2 Luciana Altieri, 1 Emilia Mancini, 2 Laura De Martino, 2 and Gian Luigi Rana 1 1 Department of Biology, Protection and Agro-Forestry Biotechnology, University of Basilicata, Potenza, Italy; and 2 Department of Pharmaceutical Science, Salerno State University, Fisciano, Salerno, Italy ABSTRACT Twelve essential oils from Mediterranean aromatic plants were tested at different doses against four fungi known as causal agents of post-harvest orange fruit rot: Botrytis cinerea, Penicillium italicum, Phytophthora citrophthora, and Rhizopus stolonifer. Essential oils were obtained from Hyssopus officinalis, Lavandula angustifolia, Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis, and Thymus vulgaris (Family Lamiaceae), Verbena officinalis (Family Verbenaceae), and Pimpinella anisum, Foeniculum vulgare, and Carum carvi (Family Apiaceae). Because preliminary in vitro experiments showed that only the oils from V. officinalis, T. vulgaris, and O. vulgare exhibited some fungistatic activity against the above-named fungi, these three essential oils were used in successive in vivo tests carried out to protect healthy ‘‘Washington navel’’ orange fruits from artificial infection by the same micromycetes. The essential oil of T. vulgaris, at a 2,000 ppm dose, controlled fruit rot by B. cinerea, P. citrophthora, and R. stolonifer but was ineffective against P. italicum. Essential oils of V. officinalis and O. vulgare inhibited infection by the first two fungi and only by P. citrophthora, respectively. This finding represents an important result, with the goal of using the essential oils as natural preservatives for food products, due to their positive effect on their safety and shelf life. Key Words:  Apiaceae  fungitoxic activity  Lamiaceae  Verbenaceae INTRODUCTION F ungi are well known as causal agents of plant dis- eases either in the field or in storage. 1 Fresh fruits of several plants are susceptible to infection by pathogenic fungi after harvest. Postharvest fruit spoilage occurs worldwide. 2 Synthetic fungicides are known to be highly effective in controlling the postharvest diseases in various vegetables and fruits. In the last decades, among the various attempts to prevent, control, or eradicate plant diseases, the main one was constituted by the development of new syn- thetic compounds. These chemicals, although effective, if continuously or repeatedly used disrupt ecosystem equilib- rium, favor outbreaks of severe diseases due to widespread development of new pathotypes resistant to one or some of them, may be toxic to nontarget organisms, and sometimes accumulate as residues, above safe limits, in the food chain. 3 The growing concern for human health 4,5 and environmental protection has led to the development of different methods for controlling postharvest fruit rot. Recently, attention has been paid to exploitation of higher plant secondary metabolites as novel chemotherapeutics in plant protection. Because of nonphytotoxicity, systemicity, easy biodegradability, and the stimulatory nature of host metabolism, plant products possess the potential to be used in pest management. 6 Moreover, even if in the last 50 years these metabolites have been considered mainly as lead compounds to act as ‘‘prototypes’’ in the pest management substances industry, some natural compounds present other advantages, such as low persistence in the environment, little mammalian toxicity resulting in good selectivity, and wide public acceptance, probably deriving from a well- established use in the food, pharmaceutical, cosmetic, and perfume industries. 7 For these reasons, in the past few years, there has been a huge increase in the use of natural sub- stances such as essential oils and plant extracts as potential antifungal agents, and plants have been unanimously rec- ognized as potential sources of fungicidal and fungistatic phytochemicals. 8,9 Several investigations have been directed in this field toward antimicrobial and fungicidal properties of essential oils. 8,10–14 The use of essential oils to control postharvest fruit diseases has been deeply investigated and is well documented. 15–23 Although in a recent article Tzortzakis 24 reported that essential oil vapor was effective in combating microbial growth during storage of fresh products and im- proved attributes related to fruit quality, inclusion of es- sential oils among postharvest control weapons needs to be further explored. Manuscript received 15 December 2009. Revision accepted 26 January 2010. Address correspondence to: Prof. Vincenzo De Feo, Department of Pharmaceutical Science, Salerno State University, Via Ponte don Melillo, 84084 Fisciano, Salerno, Italy, E-mail: defeo@unisa.it JOURNAL OF MEDICINAL FOOD J Med Food 13 (6) 2010, 1515–1523 # Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition DOI: 10.1089=jmf.2009.0285 1515