Barley and its products are good sources of antioxidants. This experiment was conducted to examine the classification and concentration of phenolic compounds, proanthocyanidins, and anthocyanins in 127 lines of colored barley. Their relationship with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was also examined. Barley was placed into seven groups using the colorimeter: hulled (black 1, black 2, black 3, and purple) and unhulled (black, blue, and purple). The contents of phenolic compounds and anthocyanins were analyzed by using HPLC. The average content of phenolic compounds in unhulled barley groups (268.6 microg/g) was higher than that in hulled (207.0 microg/g) (P > 0.05). The proanthocyanidins content was determined by modified vanillin assay. The average content of proanthocyanidins was significantly higher in purple and blue barley groups compared with black (P < 0.05). The content of anthocyanins varied from 13.0 to 1037.8 microg/g. Purple and blue barley groups contained higher average contents of anthocyanins than black (P < 0.05). The most common anthocyanin in the purple barley groups was cyanidin 3-glucoside, whereas delphinidin 3-glucoside was the most abundant anthocyanin in the blue and black groups. In colored barley, DPPH radical scavenging activity had high positive correlation to the content of phenolic compounds and proanthocyanidins.

We report high frequencies of embryo production and plant regeneration through isolated microspore culture of hot pepper (Capsicum annuum L.). Microspores cultured in modified NLN medium (NLNS) divided and developed to embryos. Globular and heart-shaped embryos were observed from 3 weeks after the beginning of culture, and many embryos reached the cotyledonary stage after 4 weeks of culture. These cotyledonary embryos developed to plantlets after transfer to solid B5 basal medium. We also optimized conditions for embryo production by varying the pretreatment media, the carbon sources, and culture densities. Heat shock treatment in sucrose-starvation medium was more effective than in B5 medium. Direct comparisons of sucrose and maltose as carbon sources clearly demonstrated the superiority of sucrose compared to maltose, with the highest frequency of embryo production being obtained in 9% (w/v) sucrose. Microspore plating density was critical for efficient embryonic induction and development, with an optimal plating density of 8 x 10(4)-10 x 10(4)/ml. Under our optimized culture conditions, we obtained over 54 embryos, and an average of 5.5 cotyledonary embryos when 10 x 10(4) microspores were grown on an individual plate.

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Plants adapt to adverse environmental conditions through physiological responses, such as induction of the abscisic acid signaling pathway, stomatal regulation, and root elongation. Altered gene expression is a major molecular response to adverse environmental conditions in plants. Several transcription factors function as master switches to induce the expression of stress-tolerance genes. To find out a master regulator for the cold stress tolerance in rice, we focused on functionally identifying DREB subfamily which plays important roles in cold stress tolerance of plants. Here, we characterized OsDREB1G ( LOC_Os02g45450 ), a functionally unidentified member of the DREB1 subgroup. OsDREB1G is specifically induced under cold stress conditions among several abiotic stresses examined. This gene is dominantly expressed in leaf sheath, blade, node, and root. Transgenic rice overexpressing this gene exhibited strong cold tolerance and growth retardation, like transgenic rice overexpressing other OsDREB1 genes. However, unlike these rice lines, transgenic rice overexpressing OsDREB1G did not exhibit significant increases in drought or salt tolerance. Cold-responsive genes were highly induced in transgenic rice overexpressing DREB1G compared to wild type. In addition, OsDREB1G overexpression directly induced the expression of a reporter gene fused to the promoters of cold-induced genes in rice protoplasts. Therefore, OsDREB1G is a typical CBF/DREB1 transcription factor that specifically functions in the cold stress response. Therefore, OsDREB1G could be useful for developing transgenic rice with enhanced cold-stress tolerance.

This study was conducted to determine the fluctuating levels of isoflavone in soybean (Glycine max L.) seeds of six varieties at different development stages. The average concentration of total isoflavone in the fully matured seed was 669 µg g −1 , whereas those in the seeds of the R5 (beginning), R6 (green full-sized) and R7 (onset of physiological maturity) stages were 145, 296 and 611 µg g −1 , respectively. Sowonkong variety was highest in total isoflavone content of the fully matured and the R7 seed among all the varieties. In all six varieties, total isoflavone levels at the R7 stage were higher than those of R5 and R6 stages. Total isoflavone concentrations rapidly increased as growth stages transitioned from R5 to R7, as indicated by a positive correlation (r = 0.80 * * * ) between the total isoflavone and growth stages. Overall, total isoflavone levels were similar between R7 and the full maturity stages. Of the various isoflavone derivatives, acetylglucoside and aglycon were not significantly correlated with total isoflavone concentrations. However, glucoside (r = 0.97 * * * ), malonylglucoside (r = 0.99 * * * ), TGIN (genistein + genistin + malonylgenistin + acetylgenistin, r = 0.93 * * * ) and TDIN (daidzein + daidzin + malonyldaidzin + acetyldaidzin, r = 0.99 * * * ) were very highly correlated with total isoflavone concentrations. As a result, they constituted most of the total isoflavones in the soybean seeds at R5, R6, R7, and full maturity stages.