Enhancing Resveratrol Bioproduction and Anti-Melanogenic Activities through Elicitation in DJ526 Cell Suspension

Resveratrol, a secondary plant metabolite, and its derivatives, including piceid, show several potential health-related biological activities. However, resveratrol production is uncommon in plants; thus, resveratrol-enriched rice (DJ526) is produced for its nutritional and therapeutic value. Here, a DJ526 cell suspension was treated with various elicitors to determine its resveratrol-production potential and elicit its biological activity. Treatments with most elicitors produced more piceid than resveratrol; as elicitation periods increased, the average piceid levels were 75-fold higher than resveratrol levels. This increase is associated with glycosylation during growth and development. The duration of exposure and concentrations of elicitors were crucial factors affecting resveratrol synthase expression. Of all the elicitors tested, jasmonic acid and methyl jasmonate (MeJA) were strong elicitors; they increased resveratrol production to ≤115.1 μg g−1 (total resveratrol and piceid content). Moreover, 5 μM of MeJA increased total resveratrol production by >96.4% relative to the control production. In addition, the extract of cell suspension treated with 5 μM of MeJA significantly reduced melanin content and cellular tyrosinase activity (24.2% and 21.5% relative to the control, respectively) in melan-a cells without disturbing cell viability. Overall, elicitation can enhance resveratrol production and elicit the biological activity of the compound, in this case, its anti-melanogenic activities, in DJ526 cell suspension.

Global Transcriptome Profiling Identified Transcription Factors, Biological Process, and Associated Pathways for Pre-Harvest Aflatoxin Contamination in Groundnut

Pre-harvest aflatoxin contamination (PAC) in groundnut is a serious quality concern globally, and drought stress before harvest further exacerbate its intensity, leading to the deterioration of produce quality. Understanding the host–pathogen interaction and identifying the candidate genes responsible for resistance to PAC will provide insights into the defense mechanism of the groundnut. In this context, about 971.63 million reads have been generated from 16 RNA samples under controlled and Aspergillus flavus infected conditions, from one susceptible and seven resistant genotypes. The RNA-seq analysis identified 45,336 genome-wide transcripts under control and infected conditions. This study identified 57 transcription factor (TF) families with major contributions from 6570 genes coding for bHLH (719), MYB-related (479), NAC (437), FAR1 family protein (320), and a few other families. In the host (groundnut), defense-related genes such as senescence-associated proteins, resveratrol synthase, seed linoleate, pathogenesis-related proteins, peroxidases, glutathione-S-transferases, chalcone synthase, ABA-responsive gene, and chitinases were found to be differentially expressed among resistant genotypes as compared to susceptible genotypes. This study also indicated the vital role of ABA-responsive ABR17, which co-regulates the genes of ABA responsive elements during drought stress, while providing resistance against A. flavus infection. It belongs to the PR-10 class and is also present in several plant–pathogen interactions.

Arachis hypogaea resveratrol synthase 3 alters the expression pattern of UDP-glycosyltransferase genes in developing rice seeds

The resveratrol-producing rice (Oryza sativa L.) inbred lines, Iksan 515 (I.515) and Iksan 526 (I.526), developed by the expression of the groundnut (Arachis hypogaea) resveratrol synthase 3 (AhRS3) gene in the japonica rice cultivar Dongjin, accumulated both resveratrol and its glucoside, piceid, in seeds. Here, we investigated the effect of the AhRS3 transgene on the expression of endogenous piceid biosynthesis genes (UGTs) in the developing seeds of the resveratrol-producing rice inbred lines. Ultra-performance liquid chromatography (UPLC) analysis revealed that I.526 accumulates significantly higher resveratrol and piceid in seeds than those in I.515 seeds and, in I.526 seeds, the biosynthesis of resveratrol and piceid reached peak levels at 41 days after heading (DAH) and 20 DAH, respectively. Furthermore, RNA-seq analysis showed that the expression patterns of UGT genes differed significantly between the 20 DAH seeds of I.526 and those of Dongjin. Quantitative real-time PCR (RT-qPCR) analyses confirmed the data from RNA-seq analysis in seeds of Dongjin, I.515 and I.526, respectively, at 9 DAH, and in seeds of Dongjin and I.526, respectively, at 20 DAH. A total of 245 UGTs, classified into 31 UGT families, showed differential expression between Dongjin and I.526 seeds at 20 DAH. Of these, 43 UGTs showed more than 2-fold higher expression in I.526 seeds than in Dongjin seeds. In addition, the expression of resveratrol biosynthesis genes (PAL, C4H and 4CL) was also differentially expressed between Dongjin and I.526 developing seeds. Collectively, these data suggest that AhRS3 altered the expression pattern of UGT genes, and PAL, C4H and 4CL in developing rice seeds.

Study on the anticancer biological mechanism of Resveratrol

Trans 3, 4 ′, 5-3 hydroxy 2 styrene (resveratrol) is a kind of naturally occurring polyphenols phytoalexin. Resveratrol has significant anti-cancer activity, mainly exists in grapes, berries, and peanuts, has anti-aging, protect the heart, antioxidant, antiproliferation, promote apoptosis and immune regulation. Resveratrol has been widely concerned in the treatment of cancer and autoimmune diseases resveratrol. Resveratrol synthase (RS) is a key enzyme in the synthesis of resveratrol synthase. In this study, RS containing genes were placed under the control of fruit-specific promoter RJ39 to transform tomatoes by transgenic method. The extraction of fruits containing RS genes showed an obvious absorption peak on the HPLC chromatographic map, and it also had an obvious inhibitory effect on the growth of Hela cells.

Characterization of cDNA Encoding Resveratrol Synthase and Accumulation of Resveratrol in Tartary Buckwheat

Resveratrol synthase (RS) is the key enzyme for biosynthesis of resveratrol which come from coumaroyl-coenzyme A (CoA) and malonyl-CoA. Here, we report the cloning and characterization of a RS gene and accumulation of resveratrol in tartary buckwheat ( Fagopyrum tataricum). FtRS was composed of 1173 bp open reading frame and 390 amino acid residues and had a theoretical molecular weight and isoelectric point value of 43.70 kDa and 6.24, respectively. The FtRS expression levels were examined in sprouts and different organs of two tartary buckwheat cultivars, Hokkai T8 (T8) and Hokkai T10 (T10). FtRS transcript levels and resveratrol contents were higher under the dark condition compared with light condition. The expression levels of different organs of T10 was not observed significant variations compared to different organs of T8. Interestingly, resveratrol was detected in the sprouts developmental stages, but no resveratrol could not detect in any other organs of both T8 and T10. Therefore, we suggest that the resveratrol content in tartary buckwheat sprouts may be attributed mainly to the dark condition. The characterization of FtRS will be helpful for better understanding of the resveratrol biosynthesis in tartary buckwheat.

A survey of genes involved in Arachis stenosperma resistance to Meloidogyne arenaria race 1

Root-knot nematodes constitute a constraint for important crops, including peanut (Arachis hypogaea L.). Resistance to Meloidogyne arenaria has been identified in the peanut wild relative Arachis stenosperma Krapov. & W. C. Greg., in which the induction of feeding sites by the nematode was inhibited by an early hypersensitive response (HR). Here, the transcription expression profiles of 19 genes selected from Arachis species were analysed using quantitative reverse transcription–polymerase chain reaction (qRT-PCR), during the early phases of an A. stenosperma–M. arenaria interaction. Sixteen genes were significantly differentially expressed in infected and non-infected roots, in at least one of the time points analysed: 3, 6, and 9 days after inoculation. These genes are involved in the HR and production of secondary metabolites related to pathogen defence. Seven genes encoding a resistance protein MG13, a helix-loop helix protein, an ubiquitin protein ligase, a patatin-like protein, a catalase, a DUF538 protein, and a resveratrol synthase, were differentially expressed in all time points analysed. Transcripts of two genes had their spatial and temporal distributions analysed by in situ hybridisation that validated qRT-PCR data. The identification of candidate resistance genes involved in wild peanut resistance to Meloidogyne can provide additional resources for peanut breeding and transgenic approaches.