Improved malonaldehyde assay using headspace solid-phase microextraction and its application to the measurement of the antioxidant activity of phytochemicals

A modified malonaldehyde (MA) assay for antioxidant activity, which involves derivatization and headspace solid-phase microextraction (HS-SPME) was developed and validated. The recovery of MA as 1-methylpyrazole (product of MA and N-methylhydrazine) from a headspace of an aqueous solution containing MA, buffer, surfactant, and cod liver oil using HS-SPME with a PDMS/DVB fiber was 91.3 +/- 3.38%. MA was analyzed by a gas chromatograph with a nitrogen-phosphorus detector, and its detection limit was 0.0103 nmol/mL. The antioxidant activities of natural compounds were determined as the percentage inhibition of MA formed from cod liver oil oxidized by Fenton's reagents in the above aqueous solution. Sesamol inhibited MA formation most (86.1%), followed by eugenol (84.4%), capsaicin (80.7%), ethylvanillin (45.3%), and vanillin (31.6%) at a level of 50 microg/mL. This method did not require any organic solvents and is a simple, fast, and a highly sensitive method for MA determination.     

Two β-amylase genes,OsBAM2 and OsBAM3, are involved in starch remobilization in rice leaf sheaths

To identify mechanisms of starch degradation in rice leaf sheaths at the post-heading stage, we investigated the function of OsBAM2 and OsBAM3, which encode plastid-targeted active β-amylase isoforms, in starch remobilization in leaf sheaths. The starch content in the second leaf sheaths below the flag leaf (the third leaf sheaths) peaked at the flag leaf emergence stage and gradually decreased until 15 days after heading. The mRNA levels of OsBAM2 and OsBAM3 in the third leaf sheaths increased from the flag leaf emergence stage to the heading stage when the starch content began to decrease. However, these mRNA levels did not always remain high during post-heading. Overexpression of OsBAM2 or OsBAM3 markedly repressed starch accumulation in the third leaf sheaths, showing that OsBAM2 and OsBAM3 function in starch degradation in rice leaf sheaths. In contrast, no significant differences in starch content in the third leaf sheaths were detected between knockdown plants of OsBAM2 or OsBAM3 and non-transgenic wild-type plants. Our results suggest that reduced expression of the individual genes, OsBAM2 or OsBAM3, does not result in excess accumulation of starch in the leaf sheaths, probably because of the complementary function of another gene or the action of other genes encoding starch-degrading .     

Genetic relationship of body measurement traits at early age with carcass traits in Japanese black cattle

Estimates of genetic parameters were obtained for body measurement traits of 648 animals at 4 months of age, of 545 at 8 months and carcass traits of 14 972 animals with the use of an animal model by the restricted maximum likelihood procedure. The estimated heritabilities for carcass traits were high (0.41 to 0.54). At 4 months the estimated direct heritabilities for body measurement traits were moderate to high (0.28 to 0.64), except for chest width (0.19); at 8 months they were also moderate to high (0.23 to 0.49), except for chest depth and chest width (0.18 and 0.06, respectively). Maternal heritabilities for all body measurement traits were low at both ages. The results indicate that because of their moderate direct genetic correlations with body measurement traits, carcass weight, rib thickness and subcutaneous fat thickness can be improved; however, rib eye area and beef marbling standard show little such possibility considering their correlation with body measurement traits.     

Hypoglycemic activity of Gymnema sylvestre extracts on oxidative stress and antioxidant status in diabetic rats

Diabetes mellitus, which is associated with oxidative damage, has a significant impact on health, quality of life, and life expectancy. An ethanol extract of Gymnema sylvestre leaf was examined in vitro and in vivo to investigate the role of antioxidants in diabetic rats. The extract exhibited strong antioxidant activity in the assays, including TBA (56%), SOD-like (92%), and ABTS (54%). Blood glucose levels in the diabetic rats fed G. sylvestre extract decreased to normal levels. The presence of the antihyperglycemic compounds gymnemagenin and gymnemic acids in G. sylvestre extract was detected by LC/MS analysis. Lipid peroxidation levels were decreased by 31.7% in serum, 9.9% in liver, and 9.1% in kidney in the diabetic rats fed the extract. Feeding G. sylvestre extract to the diabetic rats decreased the activity of glutathione peroxidase in cytosolic liver and glutamate pyruvate transaminase in serum to normal levels.     

Evaluation of sugarcane smut resistance in wild sugarcane (Saccharum spontaneum L.) accessions collected in Japan

ABSTRACT

Sugarcane smut, caused by Sporisorium scitamineum, is one of the most important sugarcane diseases in Japan. Wild sugarcane, Saccharum spontaneum, is known to be a key breeding material to obtain high-yielding clones. In this study, we sought to identify Japanese wild sugarcane accessions with high resistance to smut. Thirty wild sugarcanes and three sugarcane cultivars were tested by the pinprick method. The results of the inoculation tests aided in identifying wild sugarcanes with high resistance to smut disease, namely JW90, Iriomote8, and Iriomote15. After screening the germplasm, progeny distribution of smut resistance from the inoculation test and dry matter productivity in the smut disease-free field were compared. The highly resistant wild sugarcane accession had a much better impact on progeny distribution of smut resistance compared with the susceptible accession. No relationship was found between smut resistance and dry matter productivity in both populations.     

Cloning of swine desmoglein 1 and its direct proteolysis by Staphylococcus hyicus exfoliative toxins isolated from pigs with exudative epidermitis

Exudative epidermitis (EE) is an acute, often fatal skin disease of piglets caused by Staphylococcus hyicus. Clinical and histopathological manifestations of EE are similar to those of staphylococcal scalded skin syndrome (SSSS), a human blistering skin disease, in which exfoliative toxins produced by Staphylococcus aureus digest the extracellular domains of desmoglein (Dsg) 1 and cause loss of epidermal cell-cell adhesion. The aims of this study were to isolate and characterize cDNA for full length of swine Dsg1, and to determine whether the extracellular domains of swine Dsg1 produced by baculovirus (sDsg1-His) could be digested by four isoforms of exfoliative toxin produced by S. hyicus (ExhA, ExhB, ExhC and ExhD). Nucleotide sequencing revealed that swine Dsg1 cDNA consisted of an open reading frame of 3138 bp, encoding a precursor protein of 1045 amino acids. Deduced amino acid sequence of the swine Dsg1 precursor were highly homologous to corresponding bovine, canine, human and murine sequences. Immunoadsorption assay with a secreted form of sDsg1-His revealed that sDsg1-His specifically absorbs the immunoreactivity of 10 human pemphigus foliaceus sera against swine keratinocyte cell surfaces, suggesting its proper conformation. When sDsg1-His was incubated in vitro with Exhs, all four isoforms of Exh directly digested sDsg1-His into smaller peptides, whereas removal of calcium from sDsg1-His completely inhibited its proteolysis by these four Exhs. Recognition and digestion of calcium-stabilized structure on the extracellular domains of swine Dsg1 by Exhs indicated that EE shares similar molecular pathophysiological mechanisms of intra-epidermal splitting with SSSS in humans.     

Calreticulin expression in neoplastic versus normal dog mammary glands: a cDNA subtraction-based study

This is the first report describing the expression of canine calreticulin (cCRT) in canine mammary gland tumour (MGT). Using cDNA subtraction method, it is found that mRNAs of CRT, cathepsin A, ovostatin, and lactotransferrin were differentially expressed in mammary adenocarcinoma as compared to hyperplasia, both of which were obtained from the dog. Furthermore, the mRNA expression levels of CRT and cathepsin A were significantly higher in canine MGT samples than in nontumour samples. In contrast, immunohistochemical studies have indicated that the expression of cCRT protein found to be detected in most of mammary gland tissues and was not correlated to the types of canine MGTs. Furthermore, cCRT was molecularly cloned, and the amino acid sequence of cCRT was found to be very similar to those of other species. Further studies are required to elucidate additional roles of cCRT in canine MGT.     

Determination of the genetic structure of remnant Morus boninensis Koidz. trees to establish a conservation program on the Bonin Islands, Japan

Background  

Morus boninensis, is an endemic plant of the Bonin (Ogasawara) Islands of Japan and is categorized as "critically endangered" in the Japanese red data book. However, little information is available about its ecological, evolutionary and genetic status, despite the urgent need for guidelines for the conservation of the species. Therefore, we adopted Moritz's MU concept, based on the species' current genetic structure, to define management units and to select mother tree candidates for seed orchards.     

Potential of near infrared spectroscopy to determine the lipid content of untreated garbage compost

The purpose of the present study was to evaluate the capability of near infrared spectroscopy (NIRS) as a simple method to monitor the lipid content of garbage compost, which is a potential inhibitor of plant growth. We conducted a cultivation experiment with vegetable mock pak choy ( Brassica rapa L. Parachinensis Group) using two application rates of four garbage composts that differed in lipid content. The input of lipid from the compost to the field showed a significant negative correlation with germination rate and plant height in the initial growth stage. Reflectance spectra of untreated and freeze-dried and milled compost samples were taken using a scanning monochromator. Second-derivative spectra and multiple regression analysis were used to develop calibration equations for lipid and moisture contents. The calibration was carried out with the short wavelength region ([SWR] 800–1100 nm) and the long wavelength region ([LWR] 1100–2500 nm) separately. The calibration equations with the LWR were more accurate than those with the SWR for lipid and moisture determinations. The accuracies of the calibration equations for untreated samples were comparable to those for freeze-dried and milled samples. In conclusion, we suggest that the application rate of garbage compost can be determined by measuring the lipid content of untreated samples by NIRS.