In recent years, Chinese herbal plants have become a main direction of development on cosmetic materials because the ethanol extracts should be the most common additives in new cosmetic formulas. The aim of this study is to assess the antibacterial activity from some Chinese herbal extracts. The experimental results would verify the antibacterial effect on Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli.
Antibacterial activity was determined with the disc-diffusion assay, the results showed that ethanol extracts of Rhus chinensis Mill exhibited the best inhibitory effect on S. aureus, and the diameter of inhibitory zone was 14.7?0.5mm. The aqueous extracts of Syzygium aromaticum showed better inhibitory zone with 13.3?1.5mm on E. coli. In the experiments of minimum inhibitory concentration and the minimum bactericidal concentration, the results showed the ethanol extracts of Rhus chinensis Mill for S. aureus had the best antibacterial effect, with a MIC value of 0.02% and MBC value of 0.09%, individually. Furthermore, Rhus chinensis Mill extract for E. coli also had the efficacy, the MIC and MBC value were 0.15% and 0.52%, respectively. However, the ethanol extracts from Syzygium aromaticum, Zingiber zerumbet and Rhus chinensis Mill were all displayed in good antibacterial effects against P.aeruginosa, with the MIC value of 0.25%, 0.25% and 0.5%; and with the MBC value of 0.26%, 0.35 and 0.54%, respectively. In conclusion, the experimental data demonstrated the ethanol extracts of Rhus chinensis Mill had better antibacterial effect on S. aureus and E. coli; the ethanol extracts of Syzygium aromaticum and Zingiber zerumbet showed the best antibacterial effect on P.aeruginosa. As well, the ethanol extracts of Syzygium aromaticum, Zingiber zerumbet and Rhus chinensis Mill were made into three antibacterial complexes adding to the essence product with special ratio and were evaluated the antibacterial efficacy by the D-value method. Finally, we acquired the D-value time all within 4 hours on S. aureus, P. aeruginosa and E. coli in the essence of the formula. The D-value time of three antibacterial complexes for S. aureus, P. aeruginosa and E. coli were from 1.4 to 2.4 hrs, from 1.5 to 2.3 hrs, and from 1.9 to 3.3 hrs, respectively.