Effects of NaCl Stress on Lutein Accumulation and Antioxidant Capacity of Broccoli Sprouts

To explore the effect of NaCl stress on the lutein enrichment and antioxidant capacity of broccoli sprouts, the "Qingfeng" broccoli seeds were used as the experimental raw material. The sprouts length, fresh weight, dry weight, moisture content, soluble protein, reducing sugar, malondialdehyde, proline, lutein content and antioxidant enzymes including superoxide dismutase, peroxidase and peroxidase catalase activity were studied in this experiment. Results showed that different NaCl concentrations had a greater impact on the growth of broccoli sprouts. As NaCl concentration increased from 0 to 300 mmol/L, the content of lutein in the sprouts first increased and then decreased. Under 100 mmol/L NaCl stress, the lutein content in 4-day old sprouts was 546.25 g/g, which was 37.54% higher than that in the control group. The sprouts length, fresh weight, dry weight, moisture content, soluble protein and reducing sugar content also increased by 20.88%, 161.16%, 68.65%, 2.86%, 54.90% and 40.0%, respectively. At the same time, the antioxidant enzyme activities of SOD, POD and CAT increased by 36.26%, 14.62%, and 32.34% respectively. The results of this study provided a new way to improve lutein content through NaCl stress on the germination of broccoli seeds, thus providing a reference for the development of functional food of broccoli sprouts.