The Effect of Silicon and Nano-Silica on Shelf Life and Some Nutritional Characteristics of Beet Microgreens at the Post-Harvest Period

Microgreens are young plants that have gained popularity among consumers due to their high nutritional value. In the present study, the shelf life and nutritional properties of beet microgreens subjected to silicon and nano-silica in the post-harvest period have been investigated. Silicon and nano-silica treatments were carried out at two levels (Control and 100 mg/L as foliar spraying), after which the microgreens were harvested and kept at 4°C for 12 days. The results showed that the activity of polyphenol oxidase enzyme increased with the increase of storage time and as a result the browning of the tissue also increased. Also, with increasing storage time, the percentage of weight loss, hydrogen peroxide, malondialdehyde and carotenoid increased and chlorophyll a, b and total, total phenol, flavonoid, antioxidant capacity and vitamin C decreased. The use of silicon and nano-silica treatment decreased the activity of polyphenol oxidase enzyme and browning of the microgreen tissue compared to the control. Application of silicon increased total chlorophyll (33.75%), total phenol (2.49%) and total antioxidant capacity (39.7%) of microgreens in the post-harvest period. Also, the use of nano-silica increased the amount of total phenol (5.73%), antioxidant capacity (55%) and vitamin C (38.77%) compared to the control. In general, the results of this research showed that the pre-harvest application of silicon and nano-silica improves the nutritional characteristics of beet microgreens in the post-harvest period.