Antimicrobial properties and application of fig seed oil as an additive for chitosan-based films

Abstract

Introduction. In this study, we aimed to test whether the antimicrobial capacity of chitosan polymer could be increased synergistically when fig seed oil, plum kernel oil, apricot kernel oil were applied in different conditions. Materials and methods. Antimicrobial effects of these oils against to certain bacterial species were evaluated with/without chitosan by agar disk/well diffusion and spectrophotometric measurement. Thin chitosan films enriched by seed oils were produced to test both antifungal and antibacterial effects in vivo and also in application. Results and discussion. Although we could not obtain significant effect in culture conditions, fig seed oil singly or in combination with apricot and plum kernel oil was able to improve anti-spoilage properties of chitosan film. While fresh lemon and banana slices wrapped only ordinary cling film showed a complete deterioration, chitosan-film could substantially prohibit microbial spoilage. Moreover, almost a complete protection against microbial spoilage has been determined for these food particularly packed by chitosanfilm enriched with fig seed oil. Besides, MD simulation was performed in order to evaluate putative interactions between oil compounds and chitosan. We have proposed that the most potential compound which is common in all theree oil extracts, is benzaldehyde. Herein, interaction through H-bonding was determined between between functional groups of the chitosan and benzaldehyde molecule by computational analysis, suggesting this might be one of possible factors for the observed contribution of fig seed oil and also other oil extracts to anti-spoilage effects of chitosan-based packaging film. Conclusions. Addition of fig seed oil alone or in combination with various extracts into food packages has an application potential in order to extend the shelf life of food by alleviating deterioration for several days.