Juice squeezed from cereal grasses harvested at the jointing stage, i.e., wheatgrass (Triticum aestivum), exhibits high antioxidant activity. Rice (Oryza sativa) may also exhibit antioxidant activity. We therefore examined the antioxidant... more
Juice squeezed from cereal grasses harvested at the jointing stage, i.e., wheatgrass (Triticum aestivum), exhibits high antioxidant activity. Rice (Oryza sativa) may also exhibit antioxidant activity. We therefore examined the antioxidant activity of juices squeezed from grasses harvested at the jointing stage for seven coloured and seven white Thai rice cultivars. The antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, β-carotene bleaching, and thiobarbituric acid reactive substances assays. The total phenolic content (TPC) and total monomeric anthocyanin content (TMAC) were also determined. Coloured (purple) rice grass juices exhibited greater antioxidant potential than the grass juices from white rice and wheat. The coloured rice cultivar Kum Doisaket exhibited the highest antioxidant activity in all assays. Correlation analysis indicated that the TPC and TMAC could be responsible for the antioxidant activity. The DNA protective properties of the coloured rice cultivars Kum Doisaket and Kum Noi and wheat were also examined. Only the Kum Doisaket cultivar exhibited a dose-dependent DNA protective effect. The notable antioxidant efficacy for the Kum Doisaket cultivar may be influenced by the high level of anthocyanins present in its grass juice. This finding suggests the possibility of developing functional foods from coloured rice grass.
A polymerase chain reaction (PCR) based approach, namely random amplified polymorphic DNA (RAPD) analysis was applied to six genotypes (three cultivars and three somaclones) of onion (Allium cepa L.) in order to assess the degree of... more
A polymerase chain reaction (PCR) based approach, namely random amplified polymorphic DNA (RAPD) analysis was applied to six genotypes (three cultivars and three somaclones) of onion (Allium cepa L.) in order to assess the degree of polymorphism among them based on their molecular fingerprints as well as constructing dendrogram describing the relationships among them. Six arbitrary 10-base primers were successfully used to amplify DNA extracted from the plant of the six genotypes. All primers showed polymorphic bands except one primer. A total of 55 amplicons (amplified fragment) were generated by tested primers in which 7 of them were polymorphic (12.73 %). The mean number of amplicons per primer varied from 8 to 11. The amplicons was sized 547 bp to1374 bp. The polymorphisms in PCR amplification products were subjected to the unweighed pair group method for arithmetic averages (UPGMA) and plotted in a phenogram. The dendrogram constructed from the similarity data showed that two main clusters were resulted. One of them included the genotypes Giza 20 and Giza 20 somaclone while, rest of genotypes was included in the second one. The second cluster was divided into two sub clusters one included genotypes Bihir red and Giza 6 while, the other sub cluster involved the somaclones of both cultivars Bihir red and Giza 6. It could be concluded that RAPD can be successfully used to detect somaclonal variations among in vitro regenerated onion plants.
