**5. Conclusions**

This study investigated systematically the antibacterial activity, antioxidant activity, and TPC of 67 spice extracts. The antibacterial activity of the spice extracts was partially ascribed to polyphenols, while detailed contributions of other antibacterial components should be elucidated in future work. Five selected spice extracts showed the strongest antibacterial activity against different strains of antibiotic-resistant *S. aureus*, and they have potential for use as antibiotic alternatives in animal feeding. Moreover, the clove, exhibiting both excellent antioxidant and antibacterial activities, has great potential as a natural food preservative in the food industry.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2076-2607/7/6/157/s1: Table S1: The calculated general score of 67 extracts of spices.

**Author Contributions:** Conceptualization, R.-Y.G.; Formal analysis, D.Z.; Funding acquisition, R.-Y.G. and H.C.; Investigation, D.Z., A.K.F., G.K. and Q.-Q.Y.; Methodology, D.Z., A.K.F., G.K. and Q.-Q.Y.; Project administration, R.-Y.G. and H.C.; Resources, X.-M.S., C.-L.S., Q.-X.L. and X.-B.X.; Supervision, R.-Y.G.; Writing—original draft, D.Z.; Writing—review and editing, R.-Y.G., X.-M.S., C.-L.S., Q.-X.L., X.-B.X., H.-B.L. and H.C.

**Funding:** This study was financially supported by the National Key R&D Program of China (2017YFC1600100), the Shanghai Basic and Key Program (18JC1410800), the Shanghai Pujiang Talent Plan (18PJ1404600), the Agri-X Interdisciplinary Fund of Shanghai Jiao Tong University (Agri-X2017004), and the Shanghai Agricultural Science and Technology Key Program (18391900600).

**Conflicts of Interest:** The authors declare no conflict of interest.
