Structural identification of new curcumin dimers and their contribution to the antioxidant mechanism of curcumin

As a part of the research project on the elucidation of the chain-breaking antioxidant mechanism of natural phenolics against the oxidation of food components, curcumin, a main turmeric pigment, was investigated. A relatively high concentration of curcumin gave three dimers as radical termination products in addition to the coupling products with curcumin and the lipid hydroperoxide. The structural analysis of these dimers and quantitative analysis of their production rates revealed that radical-radical termination mainly occurred at the 2-position of curcumin. The contribution of the pathway for production of these dimers to the antioxidant mechanism of curcumin was estimated from the concentration-dependent data of the antioxidant activity and formation rates of these termination products. The A-A termination (dimer formation) was estimated to contribute at least about 40% of the entire antioxidant process against ethyl linoleate oxidation.     

Successful measures to prevent the spread of bovine papular stomatitis in a dairy farm

Nasal papules and oral ulcers were observed in calves that were group-housed at a dairy farm. The calves were diagnosed with bovine papular stomatitis (BPS) due to parapoxvirus (PPV) infection based on virologic examinations using polymerase chain reaction to detect PPV. To prevent the spread of BPS, we isolated the affected calves, made procedural changes so that the affected herd was managed after the healthy herd, disinfected the bedding with slaked lime, disinfected the stalls and fences with invert soap, and changed the animals’ feed to soft grass which does not damage the oral cavity. As a result, we succeeded in control the infection quickly.     

Ability of alphas-Casein to suppress the heat aggregation of ovotransferrin

The effects of alphas-casein on heat aggregation of ovotransferrin (OT) were studied by heating at 80 degrees C for 20 min in 10 mM phosphate buffer, pH 7.0. The heat interactions between alphas-casein and OT were followed by turbidity development and polyacrylamide gel electrophoresis. We found that alphas-casein can effectively suppress the heat-induced aggregation of heat-labile OT. The suppressive ability of alphas-casein was reduced by the presence of NaCl on heating. Dephosphorylated alphas-casein had less ability to suppress the aggregation of OT than native alphas-casein. Our results indicate that alphas-casein interacts with the heat-denatured OT through its exposed hydrophobic surface and phosphoserine residue. Such interactions seem to be important in helping to suppress the aggregation of heated OT. The suppressive effects of alphas-casein on heat aggregation of OT would be partially ascribed to the formation of transparent gel from egg white by the addition of alphas-casein.     

Collection,preservation and distribution of Oryza genetic resources by the National Bioresource Project RICE (NBRP-RICE)

Biological resources are the basic infrastructure of bioscience research. Rice (Oryza sativa L.) is a good experimental model for research in cereal crops and monocots and includes important genetic materials used in breeding. The availability of genetic materials, including mutants, is important for rice research. In addition, Oryza species are attractive to researchers for both finding useful genes for breeding and for understanding the mechanism of genome evolution that enables wild plants to adapt to their own habitats. NBRP-RICE contributes to rice research by promoting the usage of genetic materials, especially wild Oryza accessions and mutant lines. Our activity includes collection, preservation and distribution of those materials and the provision of basic information on them, such as morphological and physiological traits and genomic information. In this review paper, we introduce the activities of NBRP-RICE and our database, Oryzabase, which facilitates the access to NBRP-RICE resources and their genomic sequences as well as the current situation of wild Oryza genome sequencing efforts by NBRP-RICE and other institutes.     

Can research on the early marine life stage of juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> forecast returns of adult salmon? A case study from eastern Hokkaido,Japan

To examine the efficacy of juvenile salmon research as a tool for forecasting adult returns, the results from a study on the early marine life stage of juvenile chum salmon, conducted in the Nemuro Strait during 1999–2002 (i.e., 1998–2001 brood years), were compared with the return rates of adult salmon. Among the four brood years, the 2000 brood year (i.e., salmon migrating to the sea in 2001) was previously reported as showing higher abundance, higher growth rate and better somatic condition during the coastal residency period. Consequently, we expected it to have the highest return rate, under a hypothesis that juvenile survival in coastal residency regulates brood-year strength. Contrary to this expectation, the 2000 brood year had almost the lowest return rate. Alternatively, a statistical model in which sea surface temperature during the first year of marine life and size at release were utilized as explanatory variables reconstructed the actual variability in return rates more accurately than that based on the early marine life stage. Possible reasons for the discrepancy between the results of the juvenile salmon research and adult returns are discussed, and we suggest improvements for future research on juvenile salmon.     

Prebiotic effect of glycerol galactoside isolated from color-faded nori in rats

Glycerol galactoside (GG; floridoside: 2-O-glycerol-α-d-galactopyranoside, and isofloridoside: 1-O-glycerol-α-d-galactopyranoside) is known to be a component of edible red seaweed nori. Recently, we have found that low-quality nori (color-faded nori), which has a low protein content, contains a large quantity of GG. From further studies, we have also found that GG has prebiotic characteristics in vitro. In this study, we evaluated the in vivo prebiotic activity of GG in rats. Dietary GG selectively increased the cecal Bifidobacterium count in rats. Other indices of prebiotics, such as pH of cecal content, organic acid concentrations, and fecal weight, also supported the existence of prebiotic activity of GG. The present data will also contribute to the development of a new method of utilizing color-faded nori as a health-promoting foodstuff.