The main objective of this study is to evaluate the effect of selected essential oils thyme chemotype linalool (Thymus zygis L.), thyme chemotype tymol (Thymus vulgaris L.), eucalyptus (Eucalyptus globulus Labill.), lavender (Lavandula angustifolia Mill.), mint (Mentha piperita L.), almond (Prunbus dulcis Mill.), cinnamon bark (Cinnamomum zeylanicum Nees), litsea (Litsea cubeba Lour. Pers), lemongrass (Cympogon citrati L. Stapf), and ginger (Zingiber officinalis Rosc.) in the vapor phase on growth, sporulation, and mycotoxins production of two Aspergillus strains (Aspergillus parasiticus CGC34 and Aspergillus ochraceus CGC87), important postharvest pathogens of green and roasted coffee beans. Moreover, the effect of the essential oils (EOs) on the sensory profile of the coffee samples treated with EOs was evaluated. The major components of tested EOs were determined by gas chromatography and mass spectrometry (GC–MS) and gas chromatography with flame ionization detector (GC-FID). The results showed that almond, cinnamon bark, lemongrass, and litsea EOs are able to significantly inhibit the growth, sporulation, and mycotoxins production by toxigenic fungi. Sensory evaluation of coffee beans treated with EOs before and after roasting showed that some EOs (except lemongrass and litsea) do not adversely affect the taste and aroma of coffee beverages. Thus, application of the vapors of almond and cinnamon EOs appears to be an effective way that could serve to protect coffee during its transport and storage from toxigenic fungi.
This study aimed to investigate the antagonistic effect of three strains of the genus Bacillus on toxigenic fungi contaminating food commodities, with emphasis on two ochratoxigenic isolates (A. ochraceus, A. westerdijkiae) and two aflatoxigenic isolates (A. flavus and A. parasiticus). In vitro studies were carried out using two different methods for cultivation tested bacilli with fungal isolatescoincubation and dual culture method. The most sensitive isolate was A. ochraceus by both used methods. B. mycoides (5.72 ± 6.4 mm) and B. subtilis (5.08 ± 2.84 mm) were able to inhibit its growth and sporulation during ten days of cultivation (both inhibited the sporulation of A. ochraceus 100%) in coincubation. The most effective in the dual culture method were B. subtilis and B. thuringiensis against A. ochraceus (growth inhibition rate 84.40%; 90.55%) and A. flavus (growth inhibition rate 91.54%; 92.43%). The most effective sporulation inhibitors were B. subtilis and B. thuringiensis, which completely inhibited the sporulation of A. ochraceus and A. parasiticus after ten days of coincubation. Likewise, all tested bacterial strains showed complete inhibition of ochratoxin A synthesis in A. ochraceus and A. westerdijkiae exposure to bacterial volatiles. So, the current study illustrated that strains of the genus Bacillus could significantly inhibit the growth, sporulation, and mycotoxin production of toxigenic aspergilli and showing the great potential as a biocontrol agent of preand post-harvest food diseases caused by microscopic filamentous fungi.
ARTICLE INFO
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.