Antimicrobial Effects of Different Essential Oil against the Rice Penicillium and Aspergillus niger

This paper aimed to investigate the antimicrobial effects of several plants essential oils against rice mildewing. Nine essential oils derived from Eucalyptus globulus,peppermint,Litsea cubeba,cumin,cloves,cinnamon,pepper,citronella,and rosemary were taken as materials,and Penicillium and Aspergillus niger from rice were taken as targets. The antimicrobial effects of single,and every mixture of two or three essential oils and the optimal ratio of the optimum mixture were determined by testing of diameter of bacteriostatic circle,minimum inhibitory concentration(MIC),minimum growth decrease concentration(MGDC)and joint inhibitory effect. The results showed that essential oils derived from cinnamon and cloves possessed the best antimicrobial effect,followed by essential oils derived from Litsea cubeba and eucalyptus globulus,among nine essential oils. Among every mixture of two essential oils,the best one against the rice Penicillium and Aspergillus niger was mixture of essential oils derived from cloves and Litsea cubeba. The MIC reached 0.1 μL/mL,which was lower by 20~180 times than that of single counterpart,when the ratio of cinnamon essential oil to Litsea cubeba essential oil was 3:1 (v/v). This study showed that mixture of essential oils from cloves and Litsea cubeba in a proper proportion should be a promising anti-mildewing agent for rice.