This study estimates the classification criteria which distinguishes the types of omega-3 health functional foods, fish oils and fish oil usages through 13C-NMR spectra and fatty acids contents analysis. The major fatty acids of omega-3, eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6) are being analyzed. 10 ethyl ester (EE) forms and 10 triglyceride (TG) forms are the most common types of fish oils for 20 omega-3 products. Gas chromatography (GC) analysis generally shows the matching EPA and DHA contents of the products listed on the notation. But EE form contents of EPA and DHA are higher and are more varied than the TG form. Most of the samples of EPA/DHA ratio show different content ratios of indicated on the products when comparing with standards. The 13C-NMR analysis of EPA and DHA on sn-1,3 and sn-2 carbonyl peak position with fish oil triglycerides display whether the reconstituted triglycerides (rTG) are being confirmed or not. As a result of the 9 TG form, the 10 TG products showed similar values: EPA sn-1, 3; 13.46~15.66, sn-2; 3.00~4.52, DHA sn-1, 3; 2.43~4.40, sn-2; 3.84~6.36. But one product showed lower contents (EPA: sn-1, 3; 5.88, sn-2; 2.86, DHA sn-1, 3; 2.29, sn-2; 5.95) of EPA, thus it can be considered a different type of oil and only matched six products according to the label. This study is intended to provide basic materials which identify the status for the types and quality of omega-3 fish oil products according to fatty acids profiles and the 13C-NMR spectrum confirmed the location specificity of EPA and DHA.

The whitebacked planthopper (WBPH) is one of the most serious insect pests of rice. The nymphs and adults suck the phloem sap which causes reduced plant vigor, stunting, yellowing of leaves. We employed a mapping population composed of 113 doubled haploid lines (DHLs), derived from a cross between resistant cultivar ‘Cheongcheong’ and susceptible cultivar ‘Nagdong’, to identify the quantitative trait loci (QTL) associated with WBPH resistance. The DH population was evaluated for resistance to WBPH using seed box screening test. The WBPH resistance of each lines or plants was estimated when susceptible check ‘Nagdong’ was killed using 1-9 scale according to Standard Evaluation System for Rice (IRRI, 1988). A linkage map was constructed with 119 polymorphic microsatellite markers using the Joinmap 4 software program to adjust for segregation distortion. Transgressive segregation was observed on WBPH resistance. Two significant QTLs conferring resistance to WBPH, qwbph6.1 and qwbph6.2, were detected in the regions of RM588-RM276 and RM527-RM528 on chromosome 6 with LOD scores of 3.7 and 2.4, respectively. They collectively explained 55% of phenotypic variation. These two QTLs have large effects on WBPH resistance and may be useful for establishment of marker assisted selection (MAS) in the rice breeding programs.

We compared the long-term metabolic effects of equal amounts of carbohydrate from potato, rice and buckwheat on glycemic indices and blood lipids in healthy subjects. Nine healthy volunteers-2 men and 7 women were studied. All subjects ate diets based on the same-7-day rotating menu differing only in that the major source of carbohydrate (about 50% of daily total calories) came either from buckwheat, rice or potato. The study was conducted with a triple crossover design over three 7 day periods. On the morning of the 8th day, fasting blood was drawn from each subject to determine serum glucose, insulin, triglycerides, total and HDL-cholesterol. Subjects were then asked to eat breakfast with their respective carbohydrate within a 20 min period. Blood samples were drawn at 30, 60, 120 and 180 min after the start of breakfast to determine glucose and insulin levels. At 30 min the glucose response to the rice meal(7.15mmol/L) and potato meal(6.71mmol/L) were greater than the response to the buckwheat meal(5.855mmol/L) (P < 0.05). The mean area under the glucose response to the curve following the rice meal was greater than that following the buckwheat meal(P < 0.05). The insulin responses to the potato and rice meals at 30 and 60 min were greater than those to the buckwheat meal (P < 0.05). The mean area under the serum insulin response curve after the rice meal was greater than of buckwheat. Blood lipids, uric acid and glycosylated hemoglobin were not affected by the three meals. The study shows that the buckwheat meal has more beneficial effects on glycemic indices than either the rice meal or potato meal in healthy subjects.