β amyloid protein (Aβ) plays a critical role in the pathogenesis of Alzheimer's disease (AD) and possibly in Aβ -induced mitochondrial dysfunction and oxidative stress. Aβ can directly cause reactive oxygen species (ROS) production. Overproduction of ROS is considered to be involved in the pathogenesis of neurodegeneration of AD. Here, we investigated 9 kinds of ramie (Boehmeria nivea, (L.) Gaud., BN; hereafter denoted as BN) for their protective action against oxidative stress in a cellular system using C6 glial cells. We observed loss of cell viability and high levels of ROS generation after treatment with hydrogen peroxide (H2O2) and Aβ25-35. However, treatments with BN extracts led to an increase in cell viability and decrease in ROS production induced by H2O2 and Aβ25-35. In particular, the extracts of BN-01 (seobang variety from Seocheon) and BN-09 (local variety from Yeonggwang) showed excellent anti-oxidative properties. This indicates that BN extracts could prevent neurodegeneration by reducing oxidative stress in cells.

Ramie (Boehmeria nivea L.) is a hardy perennial herbaceous plant of the Urticaceae family and has been grown as a fiber crop in several countries including Korea for many centuries. Ramie leaves also have been traditionally used as a major ingredient of a type of rice cake called ‘Song-pyun’ in the Southwest area of Korea, especially Yeong-Gwang province. Despite its economic importance, the molecular genetics of ramie have not been studied in detail yet. Genetic resources of ramie were widely collected from domestic local sites by Bioenergy Crop Research Center (RDA) and Yeong-Gwang Agricultural Technology Center. For the systematic and efficient management of the genetic resources, we developed SSR (simple sequence repeat) markers of ramie. To do this, we generated microsatellite-enriched genomic DNA libraries using magnetic bead hybridization selection method. 247 non-redundant contigs containing SSR motif were generated using nucleotide sequences of 376 clones from the libraries. Primer sets were designed from the flanking sequences of the repeat motif. Finally, we selected 10 SSR markers, possibly showing polymorphism among the genetic resources. Results on the genotype analysis of the ramie genetic resources using the SSR markers will be presented.

Content analysis of loliolide in the leaves of Boehmeria nivea (Bn) collected from different region during four months (June, July, August, and September) was conducted by HPLC. The content of loliolide was detected in the leaves of B. nivea from Bns-2, -7, -10, -23, -38, -41, -67, -76, and -90 in June (5.02, 6.35, 6.93, 5.89, 4.31, 4.24, 4.91, 5.12, and 5.46 mg/g, respectively), July (4.32, 6.42, 7.72, 7.97, 4.05, 4.32, 5.65, 6.67, and 5.39 mg/g, respectively), August (3.52, 5.17, 3.90, 4.27, 3.26, 4.72, 3.82, 3.30, and 3.31 mg/g, respectively), and September (7.04, 7.25, 7.43, 7.86, 6.76, 6.38, 7.60, 6.79, and 4.77 mg/g, respectively). Among them, the highest content of loliolide was found in Bn-23 and in September. These results may be useful in determining the optimal harvest time at which phytochemical reaches a maximum level.

Ramie (Boehmeria nivea L. Gaudich.) is a hardy perennial herbaceous plant of the Urticaceae family and has been grown as a fiber crop in several countries including Korea for many centuries. Ramie leaves also have been traditionally used as a major ingredient of a type of rice cake called ‘Song-pyun’ in the Southwest area of Korea, especially Yeong-Gwang province. Despite its economic importance, the molecular genetics of ramie have not been studied in detail yet. Genetic resources of ramie were widely collected from domestic local sites by Bioenergy Crop Research Center (RDA) and Yeong-Gwang Agricultural Technology Center. For the systematic and efficient management of the genetic resources, we developed microsatellite molecular markers of ramie. To do this, we generated microsatellite-enriched genomic DNA libraries using magnetic bead hybridization selection method. 216 contigs containing microsatellite repeat motif were generated using nucleotide sequences of 376 clones from the libraries. Primer sets were designed from the flanking sequences of the repeat motif. Finally, we selected 26 microsatellite markers, possibly showing polymorphism among the genetic resources. Results on the genotype analysis of the ramie genetic resources using the microsatellite markers will be presented.

Brassica napus L. (Brassicaceae) plantation has increased as its seed is the primary source for bio-diesels. This study was conducted Male sterile (MS) line (cv. 'Sun-Mang') to pollen parent (cv. 'Mokpo 64') ratio of rape plants on fatty acid compositions of six sequential stages and yield performances. Ratio of MS line to pollen parent was followed, 4:2, 10:1, and 10:2, respectively. Seeds of six sequential stages (35, 40, 45, 50, 55, and 60 days after flowering) were collected and determined using SEED FAME ESTIMATION. The results showed that oleic acid content (C18:1) of the MS to pollen parent ratio (4:2) relatively increased up to 60 days after flowering compared to other ratios. Other fatty acid compositions such as palmitic acid (C16:0), stearic acid (C18:0), linoleic acid (C18:2) and linolenic acid (C18:3) contents decreased during seed maturation period. Seed weight (1000 seeds) of MS to pollen parent ratio (4:2) was higher than other treatments. These results suggest that fatty acid compositions and seed weight was affected by ratio of MS line to pollen parent. For rape seed production, a suitable ratio of MS line to pollen parent will be required to cultivate rape plantations.