Oligomeric procyanidins in apple polyphenol are main active components for inhibition of pancreatic lipase and triglyceride absorption

Inhibitory effects of apple polyphenol extract (AP) and procyanidin contained in AP on in vitro pancreatic lipase activity and in vivo triglyceride absorption in mice and humans were examined. AP and procyanidin considerably inhibited in vitro pancreatic lipase activity. However, polyphenols, except for procyanidin, in AP (i.e., catechins, chalcones, and phenol carboxylic acids) showed weak inhibitory activities on pancreatic lipase. Procyanidins separated by normal-phase chromatography according to the degree of polymerization were also examined. Inhibitory effects of procyanidins increased according to the degree of polymerization from dimer to pentamer. On the other hand, pentamer or greater procyanidins showed maximal inhibitory effects on pancreatic lipase. These results suggested that with respect to in vitro pancreatic lipase inhibition, the degree of polymerization was an important factor and oligomeric procyanidin mainly contributed. Next, we performed a triglyceride tolerance test in mice and humans. Simultaneous ingestion of AP and triglyceride significantly inhibited an increase of plasma triglyceride levels in both models. These results suggested that the oligomeric procyanidins contained in AP inhibited triglyceride absorption by inhibiting pancreatic lipase activity in mice and humans.     

Aroma chemicals isolated and identified from leaves of Aloe arborescens Mill. Var. Natalensis Berger.

Extracts from leaves of aloe (Aloe arborescens Mill. var. natalensis Berger) were obtained using two methods: steam distillation under reduced pressure followed by dichloromethane extraction (DRP) and simultaneous purging and extraction (SPE). A total of 123 aroma chemicals were identified in the extracts obtained by both methods using gas chromatography and gas chromatography/mass spectrometry. There were 42 alcohols, 23 terpenoids, 21 aldehydes, 9 esters, 8 ketones, 6 acids, 5 phenols, and 9 miscellaneous compounds. The major aroma constituents of this extract by DRP were (Z)-3-hexenol (29.89%), (Z)-3-hexenal (18.86%), (E)-hexenal (7.31%), 4-methyl-3-pentenol (5.66%), and butanol (4.29%). The major aroma constituents of this extract by SPE were (E)-2-hexenal (45.46%), (Z)-3-hexenal (32.12%), hexanal (9.14%), (Z)-3-hexenol (1.60%), and 3-pentanone (1.41%). Terpenoids were also found as one of the major constituents. The fresh green note of aloe leaves is due to the presence of these C(6) alcohols and aldehydes as well as terpenoids.     

Characterization of acephate resistance in the diamondback moth Plutella xylostella

Decreased acetylcholinesterase (AChE) sensitivity and metabolic detoxification mediated by glutathione S-transferases (GSTs) were examined for their involvement in resistance to acephate in the diamondback moth, Plutella xylostella. The resistant strain showed 47.5-fold higher acephate resistance than the susceptible strain had. However, the resistant strain was only 2.3-fold more resistant to prothiofos than the susceptible strain. The resistant strain included insects having the A298S and G324A mutations in AChE1, which are reportedly involved in prothiofos resistance in P. xylostella, showing reduced AChE sensitivity to inhibition by methamidophos, suggesting that decreased AChE1 sensitivity is one factor conferring acephate resistance. However, allele frequencies at both mutation sites in the resistant strain were low (only 26%). These results suggest that other factors such as GSTs are involved in acephate resistance. Expression of GST genes available in P. xylostella to date was examined using the resistant and susceptible strains, revealing no significant correlation between the expression and resistance levels.     

Molecular analysis of pyrethroid resistance conferred by target insensitivity and increased metabolic detoxification in Plutella xylostella

BACKGROUND: The pyrethroid resistance of the diamondback moth Plutella xylostella (L.) is conferred by increased gene expression of cytochrome P450 to detoxify the insecticide and/or through gene mutation of the sodium channel, which makes the individual insensitive to pyrethroids. However, no information is available about the correlation between the increased metabolic detoxification and the target insensitivity in pyrethroid resistance. RESULTS: Frequencies of pyrethroid‐resistant alleles (L1014F, T929I and M918I) and two resistance‐related mutations (A1101T and P1879S) at the sodium channel and expression levels of the cytochrome P450 gene CYP6BG1 were examined individually using laboratory and field strains of P. xylostella. Real‐time quantitative PCR analysis using the laboratory strains revealed that levels of larval expression of the resistant strain, homozygous for the pyrethroid‐resistant alleles other than the M918I, are significantly higher than those of the susceptible strain. In the field strains, the expression levels in insects having the same resistant alleles as those of the resistant strains varied greatly among individuals. The expression levels were not significantly higher than those in the heterozygotes. CONCLUSION: Significant correlation between the target insensitivity and the increased metabolic detoxification in pyrethroid resistance of P. xylostella was observed in the laboratory but not in the field. Copyright © 2010 Society of Chemical Industry     

Quantitative structure-activity studies of substituted benzyl chrysanthemates: 1. Correlations between symptomatic and neurophysiological activities against American cockroaches

A number of substituted benzyl (1R)-trans-chrysanthemates and related compounds were synthesized. Their symptomatic activities in terms of levels which induce convulsions as well as cause death in American cockroaches were determined by injection with and without application of synergists as inhibitors of metabolism. The neuroexcitatory and neuroblocking activities were also determined in terms of minimum effective concentrations to induce repetitive train of impulses and conduction blockage, respectively, to central nerve cords excised from the cockroaches and immersed in Ringer's solution. Correlations between symptomatic and neurophysiological activities were analyzed quantitatively with the aid of molecular hydrophobicity parameter and regression analysis. Each symptomatic activity from which the effect of metabolism is eliminated was found to be analyzable by means of a linear combination of indices for two types of neurophysiological activity when the transport factor is separated by using the hydrophobicity parameter. A closer correlation was found between neuroblocking activity and the “convulsive” effect than between neuroexcitatory activity and the “convulsive” effect, whereas both neurophysiological effects operate together on the cockroaches resulting in paralysis and death.     

拖拉机驾驶员作业强度对其生理负荷的影响

驾驶拖拉机作业时,驾驶员的作业强度与生理负荷随着拖拉机的转向机构的不同而有较大的差别.该研究基于拖拉机两种不同的转向机构,对被测试人员实际作业时的心率和氧气的消耗量等指标进行测试,获得了不同的转向机构下被测试人员的心理和生理的变化规律.结果表明,被测人员随着不同转向机构其作业的强度也发生了变化.试验结果为设计新型的拖拉机的各系统提供了驾驶人员自身的数据,同时为改进现有的拖拉机的各系统提供重要的理论参考.     

Effects of a meal rich in 1,3-diacylglycerol on postprandial cardiovascular risk factors and the glucose-dependent insulinotropic polypeptide in subjects with high fasting triacylglycerol concentrations

It was previously reported that compared to triacylglycerol (TAG) oil, diacylglycerol (DAG) oil improves postprandial lipid response. However, the effects of DAG oil on postprandial hyperglycemia and incretin response have not yet been determined. In this study, the effects of DAG oil on both postprandial hyperlipidemia and hyperglycemia and the response to the glucose-dependent insulinotropic polypeptide (GIP) were studied. This randomized, double-blind, crossover study analyzed data for 41 individuals with high fasting triacylglycerol concentrations. The subjects ingested test meals (30.3 g of protein, 18.6 g of fat, and 50.1 g of carbohydrate) containing 10 g of DAG oil (DAG meal) or TAG oil (TAG meal) after fasting for at least 12 h. Blood samples were collected prior to and 0.5, 2, 3, 4, and 6 h after ingestion of the test meal. Postprandial TAG concentrations were significantly lower after the DAG meal compared with the TAG meal. Postprandial TAG, insulin, and GIP concentrations were significantly lower after the DAG meal compared with the TAG meal in 26 subjects with fasting serum TAG levels between 1.36 and 2.83 mmol/L. DAG-oil-based meals, as a replacement for TAG oil, may provide cardiovascular benefits in high-risk individuals by limiting lipid and insulin excursions.     

拖拉机驾驶员作业强度对其生理负荷的影响（简报）

驾驶拖拉机作业时,驾驶员的作业强度与生理负荷随着拖拉机的转向机构的不同而有较大的差别。该研究基于拖拉机两种不同的转向机构,对被测试人员实际作业时的心率和氧气的消耗量等指标进行测试,获得了不同的转向机构下被测试人员的心理和生理的变化规律。结果表明,被测人员随着不同转向机构其作业的强度也发生了变化。试验结果为设计新型的拖拉机的各系统提供了驾驶人员自身的数据,同时为改进现有的拖拉机的各系统提供重要的理论参考。     

Distribution of copper and zinc in volcanic ashes

The distribution of copper and zinc in volcanic ashes was investigated. It was found that the total copper of volcanic ashes decreased with the increase of their total silica, showing a close relationship between the total copper and the rock types of volcanic ashes. On the other hand, the total zinc showed no such correlation with the rock types.

The contents of copper and zinc in the constituent minerals Indicated that zinc was more concentrated in the heavy minerals and was closely related to the iron contents of the constituent minerals. According to the concentrations of copper and zinc in the constituent minerals and the total contents of the minerals in the andesitic ash samples, the distribution of these elements was determined to be the following order.

Cu: volcanic glass>plagioclase>pyroxenes> titanomagnetite

Zn; pyroxenes > volcanic glass> titanomagnetite>plagioclase

Since volcanic ashes belonging to rhyolite and basalt were overwhelmingly composed of volcanic glass, it was obvious that the distribution of copper and zinc was much greater in the volcanic glass of these ashes.