Effect of Maturation on Phenolics and Flavonoids Content of Greenhouse-Grown Beet Leaf

Objective: This study aims to determine how maturation stages of greenhouse-grown beet leaf influence the total phenolic content (TPC) and total flavonoid content (TFC). Methods: Beet leaf was grown under two different passive solar greenhouses in trans-Himalayan Ladakh. Leaves harvested at three maturity stages were evaluated for TPC and TFC. Results: Significant difference in TPC and TFC was observed between the three maturity stages. Midmature leaves had the highest TPC and TFC followed by mature and immature leaves. When TPC and TFC for all maturity stages were averaged, a marked difference in TPC and TFC was observed in beet leaf grown under the two passive solar greenhouses. Higher TPC and TFC were observed in the greenhouse with higher photosynthetically active radiation (PAR) and UV-transmittance. Conclusion: Beet leaf should be harvested at the midmaturity stage for consumer to benefit from elevated levels of phenolics and flavonoids.