Study on extraction technology and antibacterial of flavonoids from space breeding alfalfa

Flavonoid was extracted from space breeding alfalfa with Soxhlet extraction with orthogonal design and content was determined with spectrophotometer at 510 nm.Two bacteria were selected for in vitro antibacterial activity test.The results show that each factor with various influence with the following order: Ultrasonic extraction timeLiquid to solid ratioEthanol concentration.The highest content was 10.04 mg·g-1.The MIC of Escherichia coli and Staphylococcus aureus were 0.40 and 0.70 mg·mL-1,respectively.