Preventive effect of Kaempferia parviflora ethyl acetate extract and its major components polymethoxyflavonoid on metabolic diseases

Previously, we reported that rhizome powder of Kaempferia parviflora Wall. Ex. Baker prevented obesity and a range of metabolic diseases. In this study, to clarify which molecular mechanisms and active ingredients of K. parviflora have an anti-obesity effect, we investigated the effect of ethyl acetate extract of K. parviflora (KPE) on TSOD mice, a spontaneously obese Type II diabetes model, and on pancreatic lipase. In the TSOD groups, KPE showed a suppressive effect on body weight increase and visceral fat accumulation and also showed preventive effects on symptoms related to insulin resistance, hypertension and fatty liver. In addition, KPE also suppressed body weight increase and food intake in TSNO mice groups, which served as reference animals, at an early stage of administration. Searching for the ingredients in KPE revealed that KPE contains at least 12 kinds of polymethoxyflavonoid (PMF). Furthermore, KPE and its component PMFs showed an inhibitory effect on pancreatic lipase. The above results suggest that KPE has a preventive effect on obesity and various metabolic diseases. The mechanisms of action probably involve inhibition of pancreatic lipase by the PMFs in KPE.     

Pathological findings of hemorrhagic bowel syndrome (HBS) in six dairy cattle cases

Six adult dairy cows clinically diagnosed as hemorrhagic bowel syndrome (HBS) were the subjects of this study. The involved intestinal lesions were fixed in formalin and examined macroscopically and histopathologically. Pathological examinations revealed large intramural hematomas with necrotic foci, resulting in luminal obstruction. The mucosal layer in the lesions was detached from the intestinal wall, and there were no hemorrhagic changes in the lumen. The intramural hematomas were sometimes covered with histologically intact mucosal layer. These pathological findings were not consistent with those of “intraluminal blood clots” reported previously. Gram-positive and anti-Clostridium antibody-positive short bacilli were found in hemorrhagic necrotic areas. However, the exact relationship between Clostridium spp. observed in the lesions and HBS remains unclear, because this bacterium is a normal inhabitant in cattle.     

Analysis of polynuclear aromatic and aliphatic components in soil humic acids using ruthenium tetroxide oxidation

Although condensed aromatic components are considered to be one of the major structural units of soil humic acids (HAs) and to be responsible for the dark colour of HAs, their amount and composition remain largely unknown. In ruthenium tetroxide oxidation (RTO), condensed aromatic components are detectable as their degradation products, mainly benzenepolycarboxylic acids (BPCAs). We applied this technique to soil HAs with various degrees of humification (darkening). The yields of water‐ and dichloromethane‐soluble products from HAs upon RTO after methylation ranged from 210 to 430 mg g⁻¹ and 10–40 mg g⁻¹, respectively. Eight kinds of BPCAs with two to six carboxyl groups, and seven kinds of BPCAs with additional side chains (tentative assignment) were obtained as methylated counterparts. The yield of each BPCA and the sum of the yields of BPCAs (12–85 mg g⁻¹ HAs) increased with increasing degree of humification and aromatic C content. The compositions of BPCAs indicated that the degree of condensation was greater in the HAs with greater degrees of humification. The sum of the yields of aliphatic compounds ranged from 0.1 to 6.5 mg g⁻¹, and decreased with increasing degree of humification. The C₁₂ to C₃₀ monocarboxylic acid methyl esters accounted for > 56% of the aliphatic compounds assigned, which may be present mainly as end alkyl groups in the HA molecules. We also obtained the methylated counterparts of C₁₄ to C₂₄ dicarboxylic acids; these were possibly derived from polymethylene bridges between adjacent aromatic rings.     

Benzpyrimoxan: Design,synthesis, and biological activity of a novel insecticide

Benzpyrimoxan (5-(1,3-dioxan-2-yl)-4-{[4-(trifluoromethyl)phenyl]methoxy}pyrimidine, NNI-1501) was discovered as a novel insecticide structurally characterized by a pyrimidine derivative substituted with 1,3-dioxanyl and 4-trifluoromethylbenzyloxy groups. The compound showed remarkable activity against nymphs of rice planthoppers, including strains resistant to existing insecticides. Furthermore, benzpyrimoxan had low adverse effects on pollinators and beneficial arthropods. Because of these features, benzpyrimoxan is expected to be a suitable part of an integrated pest management strategy. In this report, the history of the discovery to reach benzpyrimoxan and details of the structure–activity relationships are described.     

Evaluation of chiral alpha-cyanoesters as general fluorescent substrates for screening enantioselective esterases

Esterases play a crucial role in industrial chemical synthesis, maintaining normal physiological metabolism and detoxifying exogenous ester-containing toxicants. To meet the rapidly increasing industrial need for all kinds of esterases, especially enantioselective esterases used to generate highly pure chiral compounds, general substrates are necessary for rapid screening, monitoring, purification, and characterization. In this study, general fluorescent substrates including phenolic derivatives and alpha-cyanoesters were evaluated for sensitivity in detecting esterases in buffer systems. Results with two different esterases and different incubation times suggested that the alpha-cyanoesters examined were significantly more sensitive at detecting esterases than the corresponding tested phenolic derivatives. More importantly, alpha-cyanoesters, containing a secondary alcohol, possess at least one chiral center; thus, they are tools to screen for enantioselective hydrolysis. Results indicated that the enantioselectivity of esterases toward general alpha-cyanoesters strongly depended on the esterase and the substrate, but the majority of esterases examined preferred S-isomers to their corresponding R-enantiomers. Most appealing was the very high enantioselectivity displayed in cytosolic esterases of the house fly. The potential utility of such esterases is discussed. In addition, the use of alpha-cyanoesters as chiral fluorescent substrates was demonstrated for monitoring in enantioselective esterases.     

Molecular cloning and expression analysis of double-stranded RNA-dependent protein kinase (PKR) in rock bream (Oplegnathus fasciatus)

We have cloned and characterized rock bream double-stranded RNA-dependent protein kinase (PKR), which is a key component of type I IFN inducible innate immune system. Full-length rock bream PKR cDNA consists of 2115 bp ORF encoding 704 amino acids, 124 bp 5′ UTR, and 529 bp 3′ UTR. Conserved domain analysis revealed that rock bream PKR contained two tandem dsRBM and kinase domain consisted of 11 kinase sub-motifs, which are characteristics found in other PKRs. Rock bream PKR was constitutively expressed in the spleen of rock bream and, upon injection of poly I:C, up-regulated not later than 12 h post injection and returned to baseline level at 48 h post injection. Although the eIF2α kinase activity of rock bream PKR was not examined in the present study, dsRNA inducible nature of rock bream PKR implies the possible important role of this gene in innate immune system of rock bream as suggested in zebrafish and flounder.     

Effectiveness of tori-lines for further reduction of incidental catch of seabirds in pelagic longline fisheries

To improve the performance of tori-lines (bird-scaring lines) in reducing incidental catch of large seabirds (albatrosses and giant petrels) in the pelagic longline fishery, we analyzed factors affecting the performance of tori-lines based on data collected by Japanese scientific observers in the southern bluefin tuna Thunnus maccoyii fishery from 2002 to 2005. We classified the variety of tori-lines by the main tori-line length and the streamer type. Two types of streamers were identified: type A, several long streamers made of nylon cord attached to the main tori-line by metal swivels; type B, many short streamers made of polypropylene packing bands braided into the main tori-line. In a model analysis, we found that the main tori-line length was an important factor affecting tori-line performance, and the two types of streamers had similar effectiveness. Since the light type B streamer has the advantage of practical feasibility, this type can be another option for use in tori-lines if used with a main tori-line of sufficient length.     

Greenhouse gases emission from paddy soil during the fallow season with and without winter flooding in central Japan

Many papers on measurements of greenhouse gases (GHGs) emission in rice paddies during a rice cropping season have been published. During a non-cropping season between Nov. and Apr., we investigated direct and indirect GHGs emissions in rice paddies. The indirect GHGs emission was evaluated as the amount of dissolved gases leaching from the paddy fields. Water management practices for the experiment were (1) continuous flooding (CF) and (2) non-flooding (NF). Although the direct CO₂ emission in the CF treatment was remained nearly zero during the non-cropping period, direct CO₂ emission in the NF treatment was continuously observed throughout the non-cropping period. The concentration of dissolved N₂O in the NF treatment was below the detection limit of the instrument during the non-cropping period except immediately after the flooding and before the drainage. The concentration of dissolved N₂O kept approximately 2 µg L^?1 during the non-cropping period in the CF treatment. The direct CH₄ emission and dissolved CH₄ were not observed during the non-cropping period. Total gas emission in the NF treatment was 10 times as large as that in the CF treatment. Direct CO₂ emission accounted for more than 90 % of the total emission in both treatments.