In order to obtain the stable viewing angle characteristics of top emission organic light emitting diodes (TEOLEDs) having strong microcavity characteristics, we fabricated nano‐porous film on the glass substrate before depositing highly reflective anode. And then, we could obtain the concave patterned anode by depositing anode on the nano‐porous film and fabricated TEOLED composed of concave patterned layers. From this approach, we could successfully obtain not only the stable color shift and luminance distribution with viewing angle but also high efficiency caused by uneven morphology. In addition, we found that the driving voltage of TEOLED could be reduced due to increased surface area effect of the concave patterned anode, so that the power efficiency was enhanced by about 15% in comparison with reference device.
Light, an essential factor in plant development, exerts a significant impact on both primary and secondary metabolism in plants. Althaea officinalis, commonly known as marshmallow, offers versatile applications through its leaves and roots. With a plethora of identified bioactive compounds and their extensive use in food, health, and supplements, it is widely cultivated globally. This study aimed to demonstrate the definitive positive impact of dark and light irradiation on both primary and secondary metabolite production in A. officinalis hairy roots and to elucidate the light-responsive mechanism through integrated metabolome and transcriptome analysis. When exposed to light, significant changes with a greenish colour shift were observed in 60 metabolites. Multivariate statistical analysis revealed a distinct separation between light- and dark-treated hairy roots, likely attributed to metabolites such as glutamic acid, phenylalanine, catechin hydrate, and chlorophyll. Correspondingly, the pathways significantly impacted included galactose metabolism, alanine, aspartate, and glutamate metabolism, flavone and flavonol biosynthesis, and phenylalanine metabolism. Light-responsive differentially expressed genes associated with pigment and phenylpropanoid biosynthetic pathways were analysed and compared via RNA sequencing. Furthermore, among the light-related transcription factors, including CONSTANS-LIKE and double B-box zinc finger, which are responsible for photomorphogenic modulation, were upregulated. Moreover, light-responsive genes, such as ribulose bisphosphate carboxylase, photosystem II, and chlorophyll A-B binding family protein, were upregulated. These findings emphasise that exposure of A. officinalis hairy root culture to light conditions is a useful method for enhancing most of the primary and secondary metabolites.
Pimpinella brachycarpa (Kom.) Nakai, reported to have antioxidant activity, is one of the most favored edible greens grown in Asian regions. The present study explores the variation in phenolic compounds in P. brachycarpa collected from different locations in Korea. Six phenolic compounds, i.e., catechin hydrate, chlorogenic acid, ferulic acid, benzoic acid, rutin and quercetin, were detected in the leaves, whereas among these compounds ferulic acid and quercetin were absent in the stems and benzoic acid and quercetin were absent in the roots of P. brachycarpa. The variation in phenolic compounds in plants from different locations was not as much as that among the different parts. The level of catechin hydrate content was much higher in the leaves than in the stems and roots. The amount of catechin hydrate in the leaves was 8.03 and 6.63 times higher than that of the highest catechin hydrate content in the roots and stems, respectively. The amount of benzoic acid accumulated was slightly higher (1.39 times) in the stems than the highest level in the leaves. The amount of ferulic acid accumulated was 1.9 times higher in the roots than the maximum level in the leaves. The amount of rutin accumulated was 1.91 times higher and 1.32 times lower in the roots than the highest levels in the stems and leaves, respectively. Our results indicate that phenolic compounds in P. brachycarpa varied significantly among the organs from different locations and the highest amount of phenolic compounds is contained in the leaves.
Unfortunately, in the online published article, the second author's given name was wrongly published. The correct given name should be "Hyeon Ji". Similarly the fourth author's given name and family name was swapped. The given name should be "Ye Eun" and family name should be "Park".
Global climate change and the industrial revolution have increased the concentration of tropospheric ozone, a photochemical air pollutant that can negatively affect plant growth and crop production. In the present study, we investigated the effects of O3 on the metabolites and transcriptome of tartary buckwheat. A total of 37 metabolites were identified by gas chromatography coupled with time-of-flight mass spectrometry, and principal component analysis was performed to verify the metabolic differences between non-treated and O3-treated Tartary buckwheat. The levels of most metabolites (threonic acid, tryptophan, sucrose, and raffinose) decreased significantly after the O3 treatment. On the contrary, the levels of two anthocyanins, cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside, increased more than 11.36- and 11.43-fold, respectively after the O3 treatment. To assess the effect of O3 on the genomic level, we analyzed the expression of anthocyanin biosynthesis pathway genes in O3-treated and non-treated buckwheat using quantitative real-time reverse transcription PCR. We found that the expression of all anthocyanin pathway genes increased significantly in the O3-treated buckwheat compared to that in the non-treated buckwheat. Altogether, our results suggested that O3 affected the transcripts and metabolites of tartary buckwheat, which would eventually cause phenotypic changes in plants.
Pimpinella brachycarpa Nakai, known as cham-na-mul in Korea, is a popular edible herb and vegetable. Phenolic compounds are recognized as a vital group of plant secondary metabolites that provide innumerable, valuable therapeutic properties. Elicitors are biofactors or chemicals from diverse sources that can trigger morphological and physiological responses in the target organism. This study examined the effect of methyl jasmonate (MeJA), salicylic acid (SA), and chitosan treatment on the accretion of phenolic compounds in P. brachycarpa Nakai. This plant was harvested under different concentration of elicitor treatment for time course. Eight phenolic compounds including were detected in response to elicitor using HPLC. While the untreated controls showed the lowest phenolic content, treatment with 0.3% chitosan, 0.1 mM SA, and 0.1 mM MeJA resulted in 1.43-, 1.39-, and 1.35-fold increase in the phenolic content, respectively. The highest content of most of the individual phenolic compounds followed a similar trend according to treatment type, with chitosan treatment showing the highest content, followed by SA and then MeJA treatments. Thus, we demonstrate that the treatment with optimal concentrations of these elicitors for an optimal period of time increases the production of phenolic compounds in P. brachycarpa Nakai.
The chemical composition of the different plant parts of green ( Hibiscus cannabinus L. cv. Jangdae) and purple ( H. cannabinus L. cv. Jeokbong) kenaf cultivars were investigated using high-performance liquid chromatography. Ten carotenoid and phenolic compounds were quantified in the different parts of green and purple kenaf. The accumulation of carotenoids and phenolic compounds in the different parts of both cultivars was slightly different. The total carotenoid content in all parts of purple kenaf was higher than that in green kenaf. In particular, lutein, β-carotene, and 9Z-β-carotene were found in all the plant parts of both purple and green kenaf. Most levels of these 3 carotenoids were higher in all parts of the purple cultivar than those found in the green cultivar. According to the detected phenolic compound content, the leaves of the green cultivar contained a higher level of total phenolics, even though the most levels of the individual phenolic compounds were higher in the purple cultivar due to the level of kaempferitrin, a major compound found in kenaf, being much higher than the levels observed for the other phenolic compounds. However, the flowers and stems of the purple cultivar had a higher level of total phenolics. Among the 10 different phenolic compounds, 7 (4-hydroxybenzoic acid, chlorogenic acid, p-coumaric acid, ferulic acid, benzoic acid, rutin, and kaempferol) were present in all the plant parts of both kenaf cultivars. Purple kenaf leaves contain higher levels of 4-hydroxybenzoic acid, chlorogenic acid, and rutin, whereas the purple cultivar flowers have higher levels of p-coumaric acid, ferulic acid, and benzoic acid. This study provides valuable information on the chemical composition of different plant parts of green and purple kenaf cultivars.
Glucosinolates are secondary metabolites that play important roles in plant defense and human health, as their production in plants is enhanced by overexpressing transcription factors. Here, four cabbage transcription factors (IQD1-1, IQD1-2, MYB29-1, and MYB29-2) affecting genes in both aliphatic and indolic glucosinolates biosynthetic pathways and increasing glucosinolates accumulation were overexpressed in watercress. Five IQD1-1, six IQD1-2, five MYB29-1, six MYB29-2, and one GUS hairy root lines were created. The expression of all genes involved in glucosinolates biosynthesis was higher in transgenic lines than in the GUS hairy root line, in agreement with total glucosinolates contents, determined by high-performance liquid chromatography. In transgenic IQD1-1 (1), IQD1-2 (4), MYB29-1 (2), and MYB29-2 (1) hairy root lines, total glucosinolates were 3.39-, 3.04-, 2.58-, and 4.69-fold higher than those in the GUS hairy root lines, respectively. These results suggest a central regulatory function for IQD1-1, IQD1-2, MYB29-1, and MYB29-2 transcription factors in glucosinolates biosynthesis in watercress hairy roots.
Kohlrabi (Brassica oleracea var. gongylodes) is a dietary Brassica vegetable with noted health-beneficial properties associated with its numerous metabolites. The aim of this study was to elucidate phenotypic variation between the two cultivars through comprehensive analysis of the relationship of their primary and secondary metabolites. High-performance liquid chromatography (HPLC) and gas chromatography time-of-flight mass spectrometry (GC-TOFMS) are considered useful tools for profiling primary and secondary metabolites. A total of 45 metabolites, including organic acids, amino acids, sugars, and an amine, were identified in pale green and purple kohlrabies using GC-TOFMS-based metabolic profiling. The resulting data sets were analyzed by principal component analysis to determine the overall variation, and the purple and pale green vegetables were separated by the score plots generated. Additionally, HPLC analysis of anthocyanins in both cultivars revealed that green kohlrabies did not contain any anthocyanidins, while 11 anthocyanins were quantified in the purple ones. Cyanidin was the dominant anthocyanin found in the purple cultivar, with cyanidin-3-(feruloyl)-diglucoside-5-glucoside being the major one. This study suggests that GC-TOFMS and HPLC are suitable tools to determine metabolic connection among various metabolites and describe phenotypic variation between green and purple kohlrabies.