The effects of led lighting on nitrates, nitrites and organic acids in tatsoi

Abstract

Progressive type of controlled environment horticulture, such as plant factories, enables the precise control of cultivation environment parameters. The experiments were performed at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in the year of 2017. The aim of this study was to evaluate the effects of different irradiance levels produced by solid state light-emitting diodes (LEDs) on nitrates, nitrites and organic acids contents in tatsoi (Brassica rapa var. rosularis), cultivated in the controlled environment chambers. Plants were cultivated under combinations of red (640, 660 nm), blue (445 nm) and far red (731nm) LEDs at photosynthetic photon flux density (PPFD) level of 200 µmol m-2 s-1. At the pre-harvest stage, PPFD was increased to 300 µmol m-2 s-1 by elevating the fluxes of different spectral components for 3 days. The contents of nitrates, nitrites and organic acids were evaluated. The results propose the metabolic interface between nitrates, nitrites and organic acids in green vegetables, sensitive for lighting conditions. The higher intensity of LED light at pre-harvest stage led to decreased contents of nitrates in tatsoi. The increased intensity of blue 455 nm light led to lower contents of nitrates and higher of organic acids in comparison to red 640 nm. In addition, the increased intensity of red 640 nm led to significantly higher (p≤0.05) contents of nitrites. The target management of LED light spectra and intensity at pre-harvest stage could be used to reduced nitrates and increased organic acids in tatsoi.

Microgreen nutrition, food safety, and shelf life: A review

“…Leaf area was maximal at different light intensities for different species (Jones‐Baumgardt et al., ). Increasing blue light intensity 3 days prior to harvest at 23 days decreased nitrate content in tatsoi, but reduced ascorbic acid content in plant leaves (Simanavičius & Viršilė, ).…”

Preharvest Nutrient Deprivation Reconfigures Nitrate, Mineral, and Phytochemical Content of Microgreens

“…Plant foods, including microgreen vegetables, are naturally biofortified with an array of bioactive compounds such as vitamins, minerals, and secondary metabolites [6,10]. Aside from desirable secondary metabolites however, vegetables can also accumulate antinutritive agents such as nitrate, especially under conducive protected cultivation conditions [10,11]. The metabolic products of nitrate have come under investigation for possible association with certain types of cancer and the methemoglobinemia syndrome [12].…”

The impact of color of artificial LED lighting on microgreen: a review

“…This nutrient rich condition was associated with the amplification of membrane transport activity and stomatal opening (Wu et al, 2007;Kopsell et al, 2014). To overcome nitrate residue issue in several case of leafy vegetable, the use of blue lighting treatment was strongly recommended to apply at 3 days prior harvesting schedule is reported to reduce nitrate content (Simanavicius and Virsile, 2018).…”