An Overview of LEDs’ Effects on the Production of Bioactive Compounds and Crop Quality

Abstract

Light-emitting diodes (LEDs) are characterized by their narrow-spectrum, non-thermal photon emission, greater longevity, and energy-saving characteristics, which are better than traditional light sources. LEDs thus hold the potential to revolutionize horticulture lighting technology for crop production, protection, and preservation. Exposure to different LED wavelengths can induce the synthesis of bioactive compounds and antioxidants, which in turn can improve the nutritional quality of horticultural crops. Similarly, LEDs increase the nutrient contents, reduce microbial contamination, and alter the ripening of postharvest fruits and vegetables. LED-treated agronomic products can be beneficial for human health due to their good nutrient value and high antioxidant properties. Besides that, the non-thermal properties of LEDs make them easy to use in closed-canopy or within-canopy lighting systems. Such configurations minimize electricity consumption by maintaining optimal incident photon fluxes. Interestingly, red, blue, and green LEDs can induce systemic acquired resistance in various plant species against fungal pathogens. Hence, when seasonal clouds restrict sunlight, LEDs can provide a controllable, alternative source of selected single or mixed wavelength photon source in greenhouse conditions.

Plant cell culture technology in the cosmetics and food industries: current state and future trends

“…Homogeneous and sufficient illumination and dissipation of the heat for photoauto- and photomixotroph plant cell cultures in the bioreactor are also required. However, demands in terms of the tolerable oxygen transfer rate as well as power input and the intensity (80.7–1345 μmol m −2 s −1 ) and duration (0, 8, 16, 24 h) of illumination may differ for cell growth and product formation (Chattopadhyay et al 2002 ; Eibl et al 2009a ; Hasan et al 2017 ). Werner et al ( 2017 ) propose selecting the bioreactor type depending on the most suitable volumetric oxygen transfer coefficient (k L a) to specific power input (P/V) ratio in a first step.…”

Physiological and biochemical responses of green and red perilla to LED‐based light

“…Conventional light sources (fluorescent, metal halide and high‐pressure sodium lamps) have been used in horticultural cultivation, but there are limits in their ability to control light quality and they generate excessive heat, which may cause undesirable effects on plant growth and development 2 . The development of light‐emitting diodes (LEDs) contributes to sufficient uniform lighting to plants and leads to more economic efficiency in controlled environments due to their specific wavelengths, small size, durability, long lifetime and cool emitting temperature 3,4 . Recently, many studies have shown a positive effect of LEDs on plant growth and bioactive compound accumulation in crops and medicinal plants such as lettuce, spinach, kale, basil, sweet pepper, ice plants, rapeseed rosette leaves and Crepidiastrum denticulatum 5–9 …”

Amber, red and blue LEDs modulate phenolic contents and antioxidant activities in eight Cruciferous microgreens

“…Plant secondary metabolites play significant roles in plants' survival from biotic or abiotic stresses. The antioxidant capability of such metabolites are also believed to benefit human health when consumed (Hasan et al, 2017). Recently, microgreens have become a unique sub-class of high-value fresh baby green vegetables that are readily harvested in 12-14 days.…”