Antifungal activity of combined treatments of active methylcellulosic based films containing encapsulated nanoemulsion of essential oils and µ-irradiation: in vitro and in situ evaluations

Authors: HOSSAIN, FARAH - Institut National De La Recherche Scientifique (INRS); Follett, Peter; DANG VU, KHANH - Institut National De La Recherche Scientifique (INRS); SALMIERI, STEPHANE - Institut National De La Recherche Scientifique (INRS); FRASCHINI, CAROLE - Fpinnovations; JAMSHIDIAN, MAJID - Institut National De La Recherche Scientifique (INRS); LACROIX, MONIQUE - Institut National De La Recherche Scientifique (INRS)

Submitted to: Cellulose
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/12/2018
Publication Date: 1/2/2019
Citation: Hossain, F., Follett, P.A., Dang Vu, K., Salmieri, S., Fraschini, C., Jamshidian, M., Lacroix, M. 2019. Antifungal activity of combined treatments of active methylcellulosic based films containing encapsulated nanoemulsion of essential oils and µ-irradiation: in vitro and in situ evaluations. Cellulose. 26(2):1335-1354. https://doi.org/10.1007/s10570-018-2135-2.
DOI: https://doi.org/10.1007/s10570-018-2135-2

Interpretive Summary: A plant essential oil (EO) blend of oregano and thyme was embedded in a methylcellulose film for slow release of volatiles against fungal contaminants in rice. This antifungal dispenser can be used as a patch, or package coating, or insert to prevent . The chemical and physical properties of the film were optimized and the film showed significant antifungal activity in vitro against Aspergillus niger, A.flavus, A.parasiticus and Penicillium chrysogenum. Methyl cellulose nanocomposite films containing EOs nanoemulsion showed a slow release (35%) of volatile components over 12 weeks of storage. Results show the potential for EOloaded methyl cellulose-based films to prolong shelf life of food products.

Technical Abstract: Microfluidization was used to develop methyl cellulose (MC)/ cellulose nanocrystal CNC based nanocomposite films containing a plant essential oil (EO) blend (oregano: thyme) emulsion. A three factorial experimental design was used to systematically optimize the microfluidization pressure based on size and antifungal activity of the prepared emulsion. Results showed that microfluidization of the film forming dispersions (FFD) provide a novel approach for the development of high strength bionanocomposite films. Incorporation of 7.5 % CNC into MC containing 0.50 -0.75 % EO and application of a pressure of 15000 psi created a nanoemulsion with particle size = 100 nm which exhibited significant antifungal activity in vitro against Aspergillus niger, A.flavus, A.parasiticus and P.chrysogenum. In situ tests with MC/CNC based bioactive films containing EO emulsion produced a 2 log reduction in fungal growth in infected rice during 8 weeks of storage at 28°C. In addition, combined treatment of bioactive films with an irradiation treatment at 750 Gy showed more pronounced antifungal properties than treatment with the bioactive film or irradiation alone. The addition of CNC as reinforcing filler improved the tensile strength of the nanocomposite based films by 30% and decreased water barrier properties by 4%. Methyl cellulose nanocomposite films containing EOs nanoemulsion showed a slow release (35%) of volatile component over 12 weeks of storage period. In addition the release of volatile component from film was 25% with the addition of CNC. These results show the potential for EO-loaded methyl cellulose-based films to prolong shelf life of food products.