Antimicrobial effects of a compound solution of three medicine food homology plants

China has a unique treasure house of medicine food homology plant resources. These resources provide both nutrition and bacterial infection prevention. With the rapid development of modern science and technology, the pursuit of health and food safety continues to grow. Advocating green health and paying attention to new natural food preservatives has become a new consumer trend. Here, we prepared a compound solution by combining ethanol extracts from three medicine food homology plants: Siraitia grosvenorii, Hippophae rhamnoides, and Alpinia oxyphylla. The antimicrobial activities of the compound solution were investigated using five common food spoilage microorganisms as target strains: Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Rhizopus, and Aspergillums niger. We determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for each target strain, and further examined the effects of various environmental factors on antimicrobial activity. Our results indicate that the compound solution effectively inhibited the growth of S. aureus and Rhizopus at a minimum inhibitory concentration of 7.81 mg/mL. It also inhibited the growth of B. subtilis, E. coli, and A. niger at a minimum inhibitory concentration of 15.6 mg/mL. Furthermore, the compound solution was stable under heat, ultraviolet, and light treatments, and was effective in the pH range of 3–5. Adding salt or sucrose to the compound mixture increased the antimicrobial effect synergistically, and added Fe3+ and Fe2+ also enhanced the antimicrobial activity of the compound solution. Therefore, our compound solution could be considered as a natural and effective antibacterial and antiseptic agent for food.