Lagerstroemia speciosa preservative

The invention discloses a lagerstroemia speciosa preservative which is prepared by mixing lagerstroemia specious polyphenol and nisin. A novel food preservative is prepared by mixing the lagerstroemia specious polyphenol and nisin, and the preservative is excellent in preservative effect, is a pure natural preparation and does not have any influence on the human health. Moreover, the preservative disclosed by the invention can achieve an effect of inhibiting most of bacteria, and the condition that multiple food additives are shared is greatly reduced.