Correlation coefficient of TPC, TFC and TGsC as well as DPPH assay is given in Fig. 2. Results showed that TPC and TFC are correlated with DPPH scavenging activity assay (R2 = 0.710 and R2 = 0.6078). This means that TPC and TFC (Fig. 2a and b) are contributed to the antioxidant capacities of broccoli methanolic extracts more than the correlation coefficient with total glucosinolates (R2 = 0.4878), which might partially be due to their lower antioxidant activity (Fig. 2c).