The Effect of Different Harvest Times on Phenolic Content and Antioxidant Activity in Some Microgreens

Abstract

Microgreens, which have only become popular during the last decades, are rich in phytochemicals, including phenolic compounds, which act as antioxidants. The study aimed to examine the effects of two different harvest times (cotyledon [embryonic leaves] and 1.5-true leaf stage) of five microgreens on the bioactive compounds in terms of antioxidant capacity and total phenolics. The total phenolic components ranged from 60.9 to 2153.2 mg GAE g-1 in cotyledon leaves, whereas the value varied from 96.2 to 2113.9 mg GAE g-1 in the true leaves of microgreens. Increases in the phenolic content of the first true leaves in dill and chia were detected as 57.8% and 29.6% compared to the cotyledon leaf. Among the cotyledon microgreens, the maximum phenolic content was detected in the garden cress. The antioxidant capacity of the cotyledon and true leaf stages ranged between 485.4±2.3-1985.67±24.9 µg g-1 and 508.87±5.3-2393.56±12.6 µg g-1, respectively. The maximum antioxidant capacity was detected in radish, followed by garden cress. The biggest variation between the cotyledon and first true leaves in the study was observed for red beetroot. This study revealed the alteration in the phenolic content and antioxidant activity of five cultivars based on growth stages of cotyledonary and true leaves in microgreen form.