Antioxidant activity and antimicrobial effect of tea polyphenols-cinnamon essential oil compound preservatives

To determine the antioxidant activity and antimicrobial effect against Staphylococcus aureus of tea polyphenols-cinnamon essential oil compound preservatives.The antioxidant capacity of compound preservatives was determined by in vitro oxidation resistance method.The bacteriostatic effect and the minimum inhibitory concentration ( MIC) were determined by the size of the inhibition zone. The effect of compound preservatives on Staphylococcus aureus was evaluated comprehensively by antibacterial activity, bacterial growth curve, cell wall integrity and cell membrane permeability. Results showed that IC50 of compound preservatives scavenged DPPH radical, hydroxyl radical and superoxide anion radical were 4.02 μg/m L, 9.15 μg/m L and 0.61 mg/m L respectively.Compound preservatives could effectively inhibit the growth of Staphylococcus aureus with the MIC of 0.5 mg/m L, and could damage the cell wall and cell membrane.In summary, compound preservatives had a strong antioxidant activity, and had a very good antibacterial effect with Staphylococcus aureus.The possible mechanism of inhibition was to destroy the cell wall and affect the permeability of the cell membrane.