Effects Of Light-emitting Diodes Research Articles

Effects of light-emitting diodes on the morphology and accumulation of glucosinolates, carotenoids and phenolic acids in red kale sprouts

Kale (Brassica oleracea var. acephala) has gained popularity as a nutritious and phytochemical-rich vegetable. This study has investigated the effects of three LED treatments (white, blue, and red) on the accumulation of secondary metabolites in kale sprouts. Ten DAS, the kale sprouts were harvested, and growth measurements were measured. Furthermore, selected sprouts were stored at -80 °C for further biochemical analysis, namely, phenolic acids, glucosinolates, and carotenoids. Sprouts irradiated with red LED light showed the best SL, RT, and FW values. For total GSLs, we found that kale sprouts irradiated with white LED lights showed the best results (41.59±0.41 μmol/g DW). Among the aliphatic GSLs, we found that progoitrin presented the best results under blue LED light (17.93±0.49 µmol/g DW), and among the indolic GSLs, glucobrassicin showed the best results under white and red LED light. The highest concentration of total carotenoids was found in kale sprouts under white LED light exposure (3341.27±206.96 μg/g DW). Individually, β-carotene was observed in high concentration under white LED light (1935.13±87.21 μg/g DW). Among the PAs, chlorogenic acid was found in the highest concentration in the treatments under white LED light (45.78±0.73 µg/g DW). In general, kale sprouts irradiated with white LED light showed high contents of GSLs, carotenoids, and PAs. Regarding morphological characteristics, kale sprouts under red LED light showed the most promise. This research offers a valuable approach to enhancing the phytochemicals found in kale sprouting.

Smart Hydroponic Farming System Integrated with LED Grow Lights

Vertical farming, including hydroponics, is a growing trend in the agricultural sector due to the increasing demand for food and urbanisation. Thus, hydroponics can save space and achieve faster plant growth compared to traditional farming methods. The concept of smart farming has been applied in this study to improve the ease of control and monitoring of hydroponic systems. The effects of light-emitting diodes (LEDs), light distance, and colour (purple and white) on water spinach growth in a hydroponic system were investigated. Additionally, an Internet of Things (IoT) controller was developed and implemented to facilitate the use of the system in an indoor hydroponic-based environment system. Based on the results, the distance between the LED light of 15 cm and the plants and the colour of the LED light (white) can positively impact plant growth in a hydroponic system. Using an IoT controller also allows for continuous monitoring and control of factors that influence plant growth. Hence, this research would catalyse the local smart hydroponic farming system for improved deliverables.

Characteristics of LED light-induced geometrical isomerization and degradation of astaxanthin and improvement of the color value and crystallinity of astaxanthin utilizing the photoisomerization

The effects of light-emitting diode (LED) irradiation characterized by different emission wavelengths on the E/Z-isomerization and degradation of astaxanthin were investigated. LED irradiation slightly promoted Z-isomerization of astaxanthin, whereas the all-E-isomerization was highly efficiently promoted at specific wavelengths, especially at 365 nm. Astaxanthin isomers did not degrade significantly when dissolved in ethanol and subjected to LED irradiation conditions for 300 min. However, significant degradation was achieved when ethyl acetate was used for dissolution, and the samples were irradiated at the wavelength of 405 nm. The addition of α-tocopherol suppressed the photodegradation of astaxanthin. LED irradiation significantly affected the physical properties of astaxanthin Z-isomers. Irradiation with 365, 405, and 470 nm LEDs enhanced the color value (redness) and crystallinity of the Z-isomers via an all-E-isomerization reaction. These findings can contribute to the development of technologies that can arbitrarily control the E/Z-isomer ratio and physical properties of astaxanthin.

LED white light-activated transcription factor MdHY5 inhibits ethylene biosynthesis during apple fruit ripening

Ethylene is one of the most important plant hormones involved in the climacteric fruit ripening process. Apple is a climacteric fruit, and its ripening process is regulated by ethylene. The effect of light-emitting diode (LED) light on plant growth and development has been extensively investigated; however, it remains unclear how LED light affects apple fruit ripening. Herein, we observed that the ripening of apple fruit treated with eight kinds of LED light was significantly inhibited compared with that of the dark control, with inhibition by white light being the most significant. Furthermore, the optimal light intensity for the inhibition of ethylene production was 20 μmol·m−2s−1, with an optimal light duration of 12 h per day. LED white light treatment enhanced the expression of two ELONGATED HYPOCOTYL 5 (HY5) genes, MdHY5L and MdHY5S, which encode transcription factors involved in the light signaling pathway. These two HY5s inhibited the transcription of MdACS1, a crucial rate-limiting enzyme in the ethylene synthesis pathway, by directly binding to its promoter. Collectively, these findings imply that LED white light induces the expression of MdHY5L and MdHY5S and delays the expression of the ethylene synthesis-related gene MdACS1 to prevent fruit ripening. This study preliminarily elucidates the molecular mechanism underlying LED white light-induced inhibition of ethylene synthesis in apple fruit, providing an important theoretical basis for studying how to improve the storage ability and prolong the shelf life of apple fruit.

Effects of Light-Emitting Diodes (LEDs) on Growth, Nitrates and Osmoprotectant Content in Microgreens of Aromatic and Medicinal Plants

Microgreens are receiving increasing attention due to their high content of bioactive components and their importance to human health. These emerging food products can be obtained from the seeds of different plant species, including aromatic herbs. Aromatic microgreens are gaining popularity as new functional food products. In this study, we investigated the effects of different light-emitting diode (LED) lamp spectra on the growth, pigments, nitrates, and osmoprotectant content of microgreens of Ocimum basilicum L., Trigonella foenum-graecum, Anethum graveolens, and Anthriscus cerefolium plants. Three types of artificial LED lamps were used: T0 as artificial white light, T1 as a continuous light-emitting diode with a longer blue wavelength, and T2 as a continuous light-emitting diode with a longer red wavelength. The results obtained showed that the three types of LED light had significant effects on the different parameters studied. In relation to growth parameters, such as fresh weight (FW) and microgreen height (H), the T2 treatment was most effective for fenugreek, dill, and chervil. However, in basil plants, FW and H values were higher under T1 treatment. Regarding nitrate accumulation, both T1 and T2 treatments reduced the content of this nutrient in the different species studied here. Finally, levels of chlorophyll, carotenoid, glucose, proline, and proteins were all higher in plants cultivated under T1 and T2 treatments than in control plants.

Effects of light-emitting diodes on cell biology

Currently, light-emitting diodes (LEDs) are considered a substitute for low-power lasers in phototherapy protocols. LEDs enable photobiomodulation on biological tissues and are considered safe and economical. However, the molecular and metabolic mechanisms involved in LED-induced photobiomodulation are not yet fully understood. This review summarizes the metabolic mechanisms involved in LED-induced photobiomodulation in biological tissues under different irradiation parameters and conditions. Studies on LED-induced metabolism photobiomodulation were accessed using scientific article databases, whose findings were summarized in terms of molecular and cellular mechanisms. Data from the accessed studies suggested that the molecular mechanism of LED-induced photobiomodulation involves photoacceptors, such as cytochrome C oxidase, membrane ion channels, mitochondrial modulation, and the production of ROS.

Light-Emitting-Diode-Assisted, Fungal-Pigment-Mediated Biosynthesis of Silver Nanoparticles and Their Antibacterial Activity

Nanoparticle synthesis, such as green synthesis of silver nanoparticles (AgNPs) using biogenic extracts, is affected by light, which changes the characteristics of particles. However, the effect of light-emitting diodes (LEDs) on AgNP biosynthesis using fungal pigment has not been examined. In this study, LEDs of different wavelengths were used in conjunction with Talaromyces purpurogenus extracellular pigment for AgNP biosynthesis. AgNPs were synthesized by mixing 10 mL of fungal pigment with AgNO3, followed by 24 h exposure to LEDs of different wavelengths, such as blue, green, orange, red, and infrared. All treatments increased the yield of AgNPs. The solutions exposed to blue, green, and infrared LEDs exhibited a significant increase in AgNP synthesis. All AgNPs were then synthesized to determine the optimum precursor (AgNO3) concentration and reaction rate. The results indicated 5 mM AgNO3 as the optimum precursor concentration; furthermore, AgNPs-blue LED had the highest reaction rate. Dynamic light scattering analysis, zeta potential measurement, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to characterize the AgNPs. All LED-synthesized AgNPs exhibited an antimicrobial potential against Escherichia coli and Staphylococcus aureus. The combination of LED-synthesized AgNPs and the antibiotic streptomycin demonstrated a synergistic antimicrobial activity against both bacterial species.

Effect of Light-emitting Diodes, Ultraviolet-B, and Fluorescent Supplemental Greenhouse Lights on Strawberry Plant Growth and Response to Infection by the Anthracnose Pathogen Colletotrichum gloeosporioides

Supplemental lighting is frequently used to extend daylength for strawberries (Fragaria ×ananassa) grown in greenhouses and high tunnels; however, information is limited on the effect of these lights on disease development. We evaluated the effect of ambient light and six supplemental light treatments [red, blue, and white light-emitting diodes (LEDs), separately; a combination of red, blue, and white LEDs; wide-spectrum fluorescent (WSF); and WFS + ultraviolet B (UV-B)] on plant growth and disease response of strawberries grown in a greenhouse. Plants were exposed to supplemental light treatments for 17 h each day. In the WSF+UV-B treatment, plants were exposed to WSF light during the day and to UV-B light for 3 hours during the night. Two trials were conducted; each trial contained five or six cultivars and was replicated three times. Twice during each trial, detached leaves from each cultivar in each light treatment were inoculated with a conidial suspension of the anthracnose crown rot pathogen, Colletotrichum gloeosporioides and rated for disease severity 10 days later. There was a significant difference due to light treatment and to cultivar in relative chlorophyll content and plant growth parameters. Plant injury ratings were lowest in the white LED, WSF, and WSF+UV-B treatments. Plants in the combination LED and red LED light treatments received higher injury, lower vigor scores, and lower relative chlorophyll content values than plants in all other light treatments. After inoculation of detached strawberry leaves with C. gloeosporioides in Trial 1, there was a significant effect due to light treatments on disease severity ratings (DSRs) after 18 weeks’ exposure to light treatments with the DSRs in the WSF+UV-B treatment being lower than those in all other treatments except those in the red LED treatment. There was not a significant effect in DSRs due to light treatments after 24 weeks in Trial 1 or after 4 or 22 weeks in Trial 2. There were significant effects due to cultivar on DSRs in both trials: ‘Strawberry Festival’, ‘Pelican’, and ‘Seascape’ received the lowest DSRs. This study showed an effect of supplemental light on several strawberry plant growth parameters, including a harmful effect of high-intensity red LED irradiation.

Effect of light-emitting diodes with different color rendering indexes on the ocular tissues of rat

To compare the damage of light-emitting diodes (LEDs) with different color rendering indexes (CRIs) to the ocular surface and retina of rats. Totally 20 Sprague-Dawley (SD) rats were randomly divided into four groups: the first group was normal control group without any intervention, other three groups were exposed by LEDs with low (LED-L), medium (LED-M), and high (LED-H) CRI respectively for 12h a day, continuously for 4wk. The changes in tear secretion (Schirmer I test, SIt), tear film break-up time (BUT), and corneal fluorescein sodium staining (CFS) scores were compared at different times (1d before experiment, 2 and 4wk after the experiment). The histopathological changes of rat lacrimal gland and retina were observed at 4wk, and the expressions of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in lacrimal gland were detected by immunofluorescence method. With the increase of light exposed time, the CFS value of each light exposed group continued to increase, and the BUT and SIt scores continued to decrease, which were different from the control group, and the differences between the light exposed groups were statistically significant. Hematoxylin-eosin (HE) results showed that the lacrimal glands of each exposed group were seen varying degrees of acinar atrophy, vacuole distribution, increasing of eosinophil granules, etc.; the retina showed obvious reduction of photoreceptor cell layer and changes in retinal thickness; LED-L group has the most significant change in all tests. Immunofluorescence suggested that the positive expressions of TNF-α and IL-6 in the lacrimal glands of each exposed group were higher than those of the control group. LED exposure for 4wk can cause the pathological changes of lacrimal gland and retina of rats, and increase the expression of TNF-α and IL-6 in lacrimal gland, the degree of damage is negatively correlated with the CRI.

Effect of Light-Emitting Diodes on Different Growth Stages of Rice

Effect of red and blue light on seed germination and seedling growth were studied in rice (Oryza sativa L.). Rice seeds were germinated in dark (control) and two types of light emitting-diodes (LED): red and green in the laboratory. The photoperiod of 6 h light and 18 h dark for LEDs treatment and 24h dark treatments with 24/18 ± 2 °C day/night temperature and 78± 2 % relative humidity were maintained in the growth room. Seed germination percentage under red light increased significantly when compared with the control; however, in blue light, germination percent decreased with little difference. First leaf length, first leaf blade length, root length, seedling fresh and dry weight increased under red and blue lights in most of the varieties. Highest germination (98%), longest root (8.18 cm) and high seedling fresh weight (0.527 g) and seedling dry weight (0.061g) in BRRIdhan71 and longest leaf in BRRIdhan75, were recorded under red light. Highest germination (96%), seedling fresh weight (0.414g) and seedling dry weight (0.047g) in BRRIdhan71, longest first leaf (6.50 cm) in BRRIdhan75 and longest root (9.37 cm) in BRRIdhan87 were recorded under blue light. First leaf blade showed only positive correlation with root length (r = 0.489), whereas seedling fresh weight showed complete correlation with seedling dry weight (r =1). Response index was positive in root length, seedling fresh and dry weight under red light. First leaf blade length, seedling fresh and dry weight had the positive response index under blue light. Within the visible spectrum, varying wave lengths of red and blue light alone altered the growth and morphology of rice seedlings, and variable reactions to illumination depended on the rice varieties, necessitating further research.
 Environ. Sci. & Natural Resources, 13(1&2): 56-62, 2020

The Effects of Light-Emitting Diode and Conventional Lighting on Sorghum Physiology and Sugarcane Aphid Interaction

Los diodos emisores de luz a menudo se utilizan para sustituir y mejorar la luz fluorescente o incandescente para las plantas que se cultivan en entornos con clima controlado. Estas luces a menudo se eligen en lugar de otras fuentes de luz debido a la durabilidad de los diodos emisores de luz, su larga vida útil, su longitud de onda mejorada para especies específicas de plantas, sus costos de energía más bajos, su riesgo de seguridad contra el calor superficial más bajo y su capacidad más fácil de incorporarse a sistemas avanzados de control climático. Sin embargo, estudios previos han demostrado que las características de Sorghum bicolor (L.) Moench (Poaceae) se alteran bajo luces de diodos emisores de luz. Por lo tanto, cultivamos 4 cultivares de sorgo en cámaras de crecimiento con luces convencionales o con diodos emisores de luz. Las plantas estaban infestadas con el pulgón de la caña de azúcar, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) o no estaban infestadas (control). El sorgo cultivado bajo luces de diodos emisores de luz era más corto y producía más hojas que eran más anchas que las de las plantas cultivadas bajo luces convencionales. Dos de los cultivares tenían tasas fotosintéticas más bajas y conductancia estomática reducida bajo luces de diodos emisores de luz. Cuando se expusieron a los áfidos de la caña de azúcar, los cultivares resistentes toleraron la alimentación de áfidos con daños reducidos bajo luces convencionales, pero fueron similares a los cultivares susceptibles cuando crecieron bajo iluminación con diodos emisores de luz. Nuestros resultados sugieren que las luces de diodos emisores de luz afectan la fisiología y morfología del sorgo y también comprometen la resistencia a los herbívoros. Nuestro estudio proporciona más evidencias de que los efectos fisiológicos de diferentes espectros de luz y su interacción con las defensas de las plantas y los herbívoros deben probarse en una amplia gama de grupos de plantas.

Guide Vane for Thermal Enhancement of a LED Heat Sink

A guide vane was installed on a heat sink to enhance the cooling effect of light-emitting diode (LED) lights. The validity of the numerical analysis was verified against the experimental results and the result of the previous studies. The effect of the guide vane on the heat dissipation performance of the heat sink was identified. The effect of the guide vane on the heat sink was qualitatively studied using the streamline and temperature contour. The cooling effect of the heat sink was enhanced by increased air supplement to the center-bottom part. A parametric study was conducted to determine the thermal resistance according to the guide vane angle, installation height, and vane length. Optimization was performed to minimize the thermal resistance using the Kriging model and micro-genetic algorithm (MGA). The cooling performance of the heat sink was enhanced by a maximum of 17.2% when the guide vane was installed.

PENGARUH LAMA PENYINARAN LAMPU LED (Light Emitting Diode) TERHADAP PERTUMBUHAN TANAMAN MICROGREENS BUNGA MATAHARI (Helianthus annuus L.) PADA BERBAGAI MEDIA TANAM

[THE EFFECT OF LIGHT EMITTING DIODE (LED) IRRADIATION DURATION ON THE GROWTH OF SUNFLOWER (Helianthus annuus L.) MICROGREENS PLANT ON VARIOUS PLANTING MEDIA]. The conversion of agricultural land into residential and office buildings causes a decrease in agricultural land every year so the development of indoor plant cultivation with the concept of urban farming, such as microgreens. Microgreens are plants in the period after germination, usually between 7-14 days. Microgreens have a nutrient content of at least 40 times higher than when they are fully grown. Sunflower plants are one of the plants that have been developed as microgreens. Sunflower (Helianthus annuus L.) is an introduced plant from America. This flower is bright yellow with a large flower head with a diameter of up to 30 cm. LED light is used to help the plant growth process that is carried out indoors. This research was conducted indoors is located in Bratang Wetan 1 No. 19c, Wonokromo, Surabaya from March 2021 to May 2021. The method used in this research is a Completely Randomized Design (CRD) system consisting of 2 factors with 3 replications. The first factor is the length of irradiation which consists of 4 levels of treatment and the second factor is the type of planting media which consists of 3 levels of treatment. The results showed that the combination of 16 hours irradiation time with soil planting medium was able to increase the growth of Sunflower microgreens plants on the variables of cotyledon width, wet weight, dry weight, and chlorophyll test.

Embryo Development and Behavior in Sea Urchin (Tripneustes gratilla) Under Different Light Emitting Diodes Condition

This study aims to evaluate the effect of light-emitting diodes (LEDs) of different wavelengths on the embryonic development, covering behavior, righting behavior, and phototaxis of collector urchins (Tripneustes gratilla). The collector urchins were divided into three groups according to the type of LED illumination they received: full-spectrum (400–750 nm wavelength), red light (630 nm), or blue light (450 nm). The results of the embryonic development experiment indicated that the blue LED group had the highest proportion of embryos reaching the prism stage at the 24th hour and the highest proportion of embryos entering the 4-arm pluteus stage, but it also had the highest death rate at the 48th hour. The full-spectrum and red LED groups exhibited similar speeds of embryonic development. In the experiment on covering behavior performed on adult urchins, our findings indicated that the blue LED group gripped the most acrylic sheets for cover, exhibiting the most covering behavior, followed by the full-spectrum group and then the red LED group. Moreover, behavior varied with coloration, as collector urchins with a lower level of melanin exhibited more covering behavior than those with a higher melanin level. In addition, the righting behavior experiments demonstrated that the blue LED group spent the longest time righting themselves. It is possible that the relatively strong stimulation from the blue LED illumination led to a higher level of stress in the collector urchins and hence slowed their righting. The phototaxis experiment revealed the most significant negative phototactic response in collector urchins when they were under the blue LED light, followed by the full-spectrum light; the red LED light did not induce any positive or negative phototactic response in the collector urchins. This experimental result verified collector urchins’ high sensitivity to and dislike of the blue LED light. The study results confirmed that the blue LED light environment accelerated the embryonic development of collector urchins; however, the relatively strong stimulation from that light also caused them to engage in covering behavior or move away from the light. These results indicate that short-wavelength irradiation significantly affects the embryonic development and behavior pattern of this species.

Phosphor converters for laser driven light sources

Due to the “efficiency droop” effect of light-emitting diodes (LEDs) under high drive currents, laser diode (LD) driven light sources are considered to replace LED lighting for the next-generation solid-state-lighting technology. In this Perspective, the history of lighting technology and the intrinsic advantages of LDs lighting are outlined. We provide a comparative overview of several typical LD phosphors, such as single crystal, transparent ceramic, phosphor-in-glass, and film thereof, as well as surface texture modification of film-type phosphor plates. The relationship between the illumination characterizations (luminance saturation, conversion efficiency, extraction efficiency, illuminating directionality, and color spatial uniformity) with thermal conductivity, pores, defects, second phases, and surface roughing or patterning is discussed. Finally, the current challenges and prospects are highlighted to provide guidelines for future research on LD phosphors.

Effect of Temperature on Channel Compensation in Optical Camera Communication

General-purpose Complementary Metal Oxide Semiconductor (CMOS) sensors perform the image desegregation in three channels (red, green, and blue) as a result of a band-pass wavelength filtering carried out using Foveon or Bayer filters. This characteristic can be used in Optical Camera Communication (OCC) systems for increasing the links’ data rate by introducing Wavelength Division Multiplexing (WDM) or Color Shift Keying (CSK) modulation schemes. However, these techniques need a compensation stage to mitigate the cross-talk between channels introduced by the filters. This compensation is performed by a Channel State Information (CSI) estimation and a zero-forcing compensation scheme. The impact of the temperature effects of light-emitting diode (LED) emissions on the zero-forcing compensation scheme’s performance has not been analyzed in depth. This work presents a comprehensive methodology and experimental characterization of this impact for Foveon and Bayer-based image sensors, assuming that the CSI is estimated under temperature conditions different from the LED’s stationary temperature regime. Besides, Signal-to-Interference-plus-Noise Ratio (SINR) and Bit Error Rate (BER) performance metrics are presented in order to estimate the repercussion in an OCC link. The results reveal that the Foveon sensor obtains more unsatisfactory performance than the Bayer-based sensor. On the other hand, the blue band is the most penalized by the thermal effect.

Effect of light-emitting diode (LED)-based colors on production performance and welfare of commercial layers

Effect of light-emitting diode (LED)-based colors on production performance and welfare of commercial layers

Effect of light-emitting diodes (LEDs) on growth of sweet basil (Ocimum basilicum) in an aquaponics system

Effect of light-emitting diodes (LEDs) on growth of sweet basil (<i>Ocimum basilicum</i>) in an aquaponics system

Effect of different LED lights spectrum on the in vitro germination of gac seed (Momordica cochinchinensis)

Momordica cochinchinensis, also known as gac, is an indigenous fruit that can commonly found in Southeast Asia. Studies had shown that M. cochinchinensis contained a higher level of carotenoids, β-carotene, and lycopene compared to other vegetables and fruits. The present study was conducted to study the effect of light conditions on gac seeds germination and effect of light-emitting diode (LED) spectra (violet, blue, green, and red) on shoot, root, and leaf formation from germinated gac seeds. A total of 60 surface sterilised uncoated gac seeds were cultured in MS media where half of them exposed to sunlight while another half kept in the enclosed cupboard. Germinated seeds were then transferred to new MS media which contained 1 mg/L of BAP and cultured under different LED lights. Gac seeds germinated well in 12 hours light treatment at the rate of 75% after one week while dark treated seeds did not germinate at all. The green LED light spectrum was the most effective for the production of the highest mean number of shoots at 4.75 ± 0.63. On the other hand, the violet LED was the most effective spectrum in producing the highest number of roots, which was 7.50 ± 0.58. Meanwhile green LED produced the highest root length of 6.25 ± 0.25 cm. Besides, green LED treatment also able to induce the highest number of leaves, which was 10.21 ± 1.89. Lateral shoot and tendrils were developed on blue LED spectrum treated seed. In conclusion, light facilitates gac seed germination while the green LED light induced better characteristics of gac plant.

Effects of Light-Emitting Diodes on the Accumulation of Phenolic Compounds and Glucosinolates in Brassica juncea Sprouts

Recent improvements in light-emitting diode (LED) technology afford an excellent opportunity to investigate the relationship between different light sources and plant metabolites. Accordingly, the goal of the present study was to determine the effect of different LED (white, blue, and red) treatments on the contents of glucosinolates (glucoiberin, gluconapin, sinigrin, gluconasturtiin, 4-methoxyglucobrassicin, 4-hydroxyglucobrassicin, glucobrassicin, and neoglucobrassicin) and phenolic compounds (4-hydroxybenzonate, catechin, chlorogenic acid, caffeate, gallate, sinapate, and quercetin) in Brassica juncea sprouts. The sprouts were grown in a growth chamber at 25 °C under irradiation with white, blue, or red LED with a flux rate of 90 μmol·m−2·s−1 and a long-day photoperiod (16 h light/8 h dark cycle). Marked differences in desulfoglucosinolate contents were observed in response to treatment with different LEDs and different treatment durations. In addition, the highest total desulfoglucosinolate content was observed in response to white LED light treatment, followed by treatment with red LED light, and then blue LED light. Among the individual desulfoglucosinolates identified in the sprouts, sinigrin exhibited the highest content, which was observed after three weeks of white LED light treatment. The highest total phenolic contents were recorded after one week of white and blue LED light treatment, whereas blue LED irradiation increased the production of most of the phenolic compounds identified, including 4-hydroxybenzonate, gallate, sinapate, caffeate, quercetin, and chlorogenic acid. The production of phenolics decreased gradually with increasing duration of LED light treatment, whereas anthocyanin accumulation showed a progressive increase during the treatment. These findings indicate that white LED light is appropriate for glucosinolate accumulation, whereas blue LED light is effective in increasing the production of phenolic compounds in B. juncea sprouts.