Abstract:In this study，glucoraphanin （GRA）was extracted from broccoli by water extraction method，and then glucoraphanin extract（GRAE）was prepared by freeze-drying method.The main components of GRAE were analyzed and the results showed that it contained GRA（2.04±0.10）%，polysaccharide（27.48±1.84）%，polyphenol（31.2±1.6）%，uronic acid （0.78±0.05）% and protein （28.46±0.75）%.The antibacterial and immunomodulatory activities in vitro were further studied.The results showed that the bacteriostatic circle diameters of GRAE against three pathogenic bacteria （Escherichia coli，Salmonella and Staphylococcus aureus）at 1000 μg/mL were （19.21±0.29），（19.10±0.42）and （16.78±0.86）mm，respectively.And the minimal inhibitory concentration（MIC）values were 62.5，31.25，250 μg/mL，respectively.The above results indicated that GRAE had a certain inhibitory effect on three pathogenic bacteria.Moreover，the inhibitory effect of GRAE on E.coli and Salmonella was better than that on S.aureus.In addition，the immunoregulatory activity test showed that the cells activity of RAW264.7 cell line was（157.6±3.5）% and the phagocytoses of RAW264.7（A490：0.926±0.035）was 1.7 times higher than the control group （A490：0.543±0.014）at 100 μg/mL of GRAE in vitro.These results indicating that GRAE had certain promoting effects on the proliferation and phagocytic activity of RAW264.7 cell line.