Citrus Essential Oils' Antibacterial Effects against Food-Borne Bacteria.

The Rutaceae family comprises more than 2,000 species across 160 genera, inside to this family there is the genus Citrus, important food crops, and some are grown as garden ornamentals. The Citrus species originated from Northern India, Northern Myanmar, Southern China, and Southeast Asia (Wu et al. 2018). The citrus genus and subsequently spread all over the world in factit is widely used in the preparation of food, both sweet and savory.Citrus plants constitute one of the main sources of essential oil, which are extensively studied for their potential uses in the food industry (Mustafa 2015).Citrus fruits have numerous health benefits thank to their characteristics that consist of high levels of compounds such as phenols, flavonoids, limonoids, essential oils (EOs), and vitamins, particularly vitamin C and carotenoids, that give a particular flavour and aroma (Bora et al. 2020). For what concerns Citrus essential oils (CEOs) they have a lot of properties, in fact theare antioxidants, antidiabetic, antifungal and antibacterial which have important applications in the pharmaceutical, sanitary, cosmetic, agricultural, and food industries (Palazzolo et al. 2013; Mancuso et al. 2019; Mancuso 2019; Mancuso et al. 2018; Mancuso 2018; mancuso 2017; Mancuso 2015 ). Citrus essential oils are a mixture of about 400 compounds of which 85-99% consist of volatile compounds and 1-15% of non- volatile compounds (Fisher and Phillips 2008). The volatile fraction is a mixture of mono (?-/?-pinene, sabinene, ?-myrcene, d-limonene, linalool, ?-humulene, and ?-terpineol) and sesquiterpenes and their oxygenated derivates (such as alcohols, acids, chetones, aldehydes and esters (González-Mas et al. 2019). Limonene is the major chemical component of CEOs (Svoboda and Greenaway 2003). The composition of CEOs varies markedly based on variety, season, and geographic location, as well as the ripening stage of the fruit (Burt 2004)). The chemical compositions of CEOs permit to be exploited in the food industry both to counteract the growth of pathogenic bacteria and to lengthen the freshness of food ensuring high food quality and safety and thus replace the chemical preservatives which are now being overused, moreover they can use for packaging too (Calo et al. 2015). This study aimed to test 9 citrus essential oils and 4 terpenes against 11 food-borne pathogenic bacteria isolated from various types of food to verify whether the CEOs have antibacterial activities against these pathogens and whether they can be considered as natural preservatives or as substances to add to food packaging.