In vitro Antifungal activities of Essential oils extracted from Fresh Leaves of Cinnamomum zeylanicum and Ocimum gratissimum against Foodborne pathogens for their use as Traditional Cheese Wagashi conservatives

Abstract

Alternative natural additives are needed in order to guarantee food safety in preservation against foodborne pathogens. Aromatic plants are traditionally employed for seasoning and prolongation of shelf life of food. The majority of their properties are due to the essential oils produced by their secondary metabolism. The objective of this study was to assess in vitro antifungal activity of essential oils extracted from fresh leaves of Cinnamomum zeylanicum and Ocimum gratissimum obtained by hydrodistillation with Clevenger apparatus against spoilage and pathogens moulds Aspergillus terreus, Aspergillus ustus, Aspergillus niger, Aspergillus aculeatus, Penicillium brevicompactum and Scopulariopsis brevicaulis both isolated from wagashi. The screening of their antifungal activity was carried out by determination of antifungal activity parameters as mycelial growth inhibition, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). Results obtained from this study showed that Ocimum gratissimum essential oil was the most effective as antifungal agent among the essential oils tested due probably to its prominent concentration in phenolic compound thymol with MIC ranged from 600 to 800 mg/L. Scopulariopsis brevicaulis and Aspergillus terreus were the most sensible strains with minimum fungicidal concentration (MFC) varying from 600 to 1000 mg/L while Aspergillus aculeatus was the most resistant mould of all to essential oil of cinnamon. With the rise of this study, it is shown that Cinnamomum zeylanicum and especially Ocimum gratissimum essential oils could be regarded as a very promising preservative for wagashi in order to prevent the mycelia growth responsible of its deterioration.