Differential expression profiles of anthocyanidin biosynthesis gene during black rice seed development

The black rice (Oryza sativa cv. Heugjinju) is rich in anthocyanins which is beneficial to human health. To correlate the biosynthesis of the pigments with relevant genes, the mRNA level of genes involved in anthocyanin biosynthesis was monitored by quantitative real-time polymerase chain reaction (qRT-PCR) during seed development of black rice. The mRNA level of F3’H, DFR, and ANS, key enzymes in anthocyanidin biosynthesis, peaked at 10 days after flowering. In general, the absolute level of ANS was approximately one order higher than F3’H, F3’5’H, and DFR in 10 days after flowering. The transcript level of major seed protein gene GluA-3, taken as reference, was also at the highest on the 10 days after flowering. However, the level of CHS isogenes was highest at 15 or 20 days after flowering. The highest transcript level of the genes, except CHS, preceded the highest anthocyanidin content by 5 days. This pattern coincided with an increase of anthocyanin content between 10 and 15 days after flowering. From these findings, it is suggested that particular CHS isoforms might be responsible for the anthocyanin production in black rice

Phenolic compound production by different morphological phenotypes in hairy root cultures of Fagopyrum tataricum Gaertn.

Hairy roots were obtained after inoculating sterile young stems of Fagopyrum tataricum with Agrobacterium rhizogenes R1000. The established roots displayed two morphological phenotypes when cultured on hormone-free medium containing Murashige-Skoog salts and vitamins. The thin phenotype had a higher growth rate than the thick phenotype. Further, the phenolic compound content of the thin phenotype was higher than that of the thick phenotype. In terms of their total dry weight, the thin phenotype produced an almost double amount of (-)-epigallocatechin as well as more than 51.5% caffeic acid, 65% chlorogenic acid, and 40% rutin compared to the thick phenotype after 21 days of culture. Therefore, selection of the optimal morphological phenotype of hairy roots of tartary buckwheat is an important factor for improved phenolic compound production

Effect of cytokinins on growth and phenylpropanoid accumulation in Tartary buckwheat sprouts (Fagopyrum esculentum Moench)

This study analyzed the effect of plant hormones, zeatin, 6-benzyl amino purine (BAP), kinetin, and thidiazuron (TDZ) on the growth of Tartary buckwheat sprouts and analyzed the fresh weight, shoot and root length, and production of phenolic compounds. All the hormone-treated plants at the lowest concentration (0.1 mg/L) showed the highest levels of growth parameters (fresh weight, shoot, and root length) when compared to the control. Among the various hormones treatment, the plant treated with 1 mg/L of BAP, kinetin, and zeatin showed the highest total phenolic level, whereas the TDZ showed the highest accumulation of total phenolic at the lowest concentration (0.1 mg/L). A total of 6 compounds were identified (4-hydroxybenzoic acid, caffeic acid, chlorogenic acid, p-coumaric acid, rutin, and trans-cinnamic acid) were quantified by high liquid performance chromatography (HPLC) after treatment of plant with different concentrations of hormones. Among these individual phenolic compounds, at the higher hormonal concentration (1 mg/L) the rutin showed the highest accumulation in BAP, zeatin, and kinetin treated sprout, whereas in the TDZ treated sprout the rutin content was highest at the lowest concentration (0.1 mg/L). From these results, it is suggested that BAP, zeatin, and kinetin at the lowest concentrations might positively enhance the growth of buckwheat sprouts, whereas at the highest hormonal treatment the accumulation of the phenolic compounds was higher. However, in TDZ treatment the growth and phenolic compound accumulation were highest at the lowest concentration. From these results, it is showed that suitable concentrations might enhance the growth and phenolic compound accumulation in Tatary buckwheat sprout