用卤虫(Artemia salina L.)评价杀虫活性

[目的]以卤虫(Artemia salina L.)为模式生物对化合物的药理活性进行初步评价.对10种不同作用机制的14种杀虫剂进行了生物筛选试验.[结果]14种供试杀虫剂中有13种对卤虫有显著的毒杀效果,作用于以γ-氨基丁酸为神经递质传导系统的化合物及蜕皮激素类似物效果最为显著.[结论]用卤虫筛选杀虫剂活性的方法简便,对多种作用机制的杀虫剂灵敏.     

阿根廷中部发现2,4-滴抗性杂草芸苔(L.)

<正>阿根廷布宜诺斯艾利斯省中部检测到对2,4-滴除草剂产生抗性的杂草——芸苔(L.),该杂草俗称"Nabo",属于十字花科,原产地为欧洲和亚洲,多生于围场、沿岸和边缘地区。前两年,在布宜诺斯艾利斯省的中部和东南部,已经进行了2,4-滴防控杂草的研究。有人怀疑在阿根廷布宜诺斯艾利斯省的Azul存在抗性生物。     

Long-term effect of pulse crops inclusion on soil–plant nutrient dynamics in puddled rice (Oryza sativa L.)-wheat (Triticum aestivum L.) cropping system on an Inceptisol of Indo-Gangetic plain zone of India

Given inherent qualities like N-fixation, P-solublization and nutrient recycling pulses remain the most preferred option for diversification of cereal-based rotations. A long-term experiment was used to assess the effect of including pulses in rice–wheat rotation on soil–plant nutrient dynamics under inorganic and organic nutrient management. Results revealed that pulses were equally responsive to organic and inorganic nutrient management while, growth of cereals especially wheat was restricted severely under organic production system due to low nutrient input. The annual input (kg ha^?1) of N (103.6–160.8) and P (25.9–34.7) under organic treatment was almost ½ of the recommended inorganic rate, while organics supplied higher K and S. Under organic management, the apparent balance of all the nutrients was negative whereas, inorganic fertilization resulted in positive balance of N, P and Zn. Long-term inclusion of pulses in rice–wheat rotation significantly increased soil organic C and available nutrients thus, increased the nutrient uptake by cereals. Mungbean inclusion in rice–wheat rotation significantly (P ≤ 0.05) increased uptake of N (23.0 %), P (32.9 %) and K (21.1 %) by rice crop. Continuous inorganic fertilization enriched soil available N, P, Zn and B. While organic management maintained higher SOC, available K and S over inorganic treatment. Thus, the study suggested that under organic management N and P nutrition is limiting factor for cereals and needs inorganic supplementation. The study also indicates the need for including pulses in conventional rice–wheat system for optimum nutrient acquisition and long-term soil health management.     

从罗望子(Tamarindus indica L.)果实提取酒石酸的生产工艺研究

酒石酸用途很广,应用于化工原料、纺织工业印染的固定剂、电镀工业、食品工业、制药工业,以及其他轻工业如鞣革、制镜、照相等,我国每年的消耗量据有关商业部门资料在百吨以上。我国酒石酸的工业生产主要靠合成和从葡萄酒酒脚中提取,但远远不能满足国内需要,不但数量上存在供求悬殊,而且合成品不适于食品工业,每年要     

Effects of Onion (Allium cepa L.) Extract Administration on Intestinal α-Glucosidases Activities and Spikes in Postprandial Blood Glucose Levels in SD Rats Model

Diets high in calories and sweetened foods with disaccharides frequently lead to exaggerated postprandial spikes in blood glucose. This state induces immediate oxidant stress and free radicals which trigger oxidative stress-linked diabetic complications. One of the therapeutic approaches for decreasing postprandial hyperglycemia is to retard absorption of glucose by the inhibition of carbohydrate hydrolyzing enzymes, α-amylase and α-glucosidases, in the digestive organs. Therefore, the inhibitory activity of Korean onion (Allium cepa L.) extract against rat intestinal α-glucosidases, such as sucrase, maltase, and porcine pancreatic α-amylase were investigated in vitro and in vivo. The content of quercetin in ethyl alcohol extract of onion skin (EOS) was 6.04 g/100 g dried weight of onion skin. The in vitro half-maximal inhibitory concentrations (IC(50)) of EOS and quercetin, a major phenolic in onion, on rat intestinal sucrase were 0.40 and 0.11 mg/mL, respectively. The postprandial blood glucose lowering effects of EOS and quercetin were compared to a known type 2 diabetes drug (Acarbose), a strong α-glucosidase inhibitor in the Sprague-Dawley (SD) rat model. In rats fed on sucrose, EOS significantly reduced the blood glucose spike after sucrose loading. The area under the blood glucose-time curve (AUC(last)) in EOS-treated SD rats (0.5 g-EOS/kg) was significantly lower than in untreated SD rats (259.6 ± 5.1 vs. 283.1 ± 19.2 h·mg/dL). The AUC(last) in quercetin-treated SD rats (0.5 g-quercetin/kg) was similar to in EOS-treated group (256.1 ± 3.2 vs. 259.6 ± 5.1 h·mg/dL). Results from this study indicates that although quercetin does have blood glucose lowering potential via α-glucosidase inhibition, there are other bioactive compounds present in onion skin. Furthermore, the effects of two weeks administration of EOS in a high carbohydrate-dietary mixture (Pico 5053) on sucrase and maltase activities in intestine were evaluated in SD rat model. Compared to the upper and middle parts of intestine, the activities of sucrase in the lower parts of intestine remained significantly higher after two weeks of EOS treatment. These results indicate that EOS may improve exaggerated postprandial spikes in blood glucose and glucose homeostasis since it inhibits intestinal sucrase and thus delays carbohydrate absorption, although clinical trials are needed.     

黄花蒿(Artemisia annua L.)提取物对两种病原真菌的生物活性

以石油醚Ⅰ(30℃～60℃)、石油醚Ⅱ(60℃～90℃)、乙醇和丙酮等4种溶剂对黄花蒿的根、茎、叶进行初步提取,采用生长速率法测定不同提取物对玉米小斑病菌、棉花枯萎病菌的抑菌活性。结果表明,黄花蒿提取物对玉米小斑病菌的生物活性好于棉花枯萎病菌;黄花蒿叶的提取物抑菌效果最好,根的抑菌效果最差;叶的石油醚(60℃～90℃)提取物对玉米小斑病菌EC50为156.32mg/L;而叶的丙酮提取物对玉米小斑病菌的EC50为82.37mg/L。     

Tocopherols in sea buckthorn (<Emphasis Type="Italic">Hippophaë rhamnoides</Emphasis> L.) berry oil

The free tocopherol content in whole berries of six sea buckthorn cultivars grown in northeastern Poland and Belorussia was determined with HPLC. The total free tocopherol content in oil from whole berries was 101.4–128.3 mg/100 g of oil. α-Tocopherol was the predominant tocopherol of sea buckthorn berries, and only traces of γ-tocopherol were detected in the oil. α- and δ-Tocopherols constituted 62.5–67.9% and 32.1–37.5% of total tocopherol, respectively. The total free tocopherol content in oil of sea buckthorn cv. Nadbaltycka increased during maturation from 40.4 to 109.8 mg/100 g of oil. Green berries contained a marked amount of γ-tocopherol, but its content rapidly declined to traces when the color of berries turned from green to olive-yellow.     

2,2′-oxo-1,1′-azobenzene: microbial transformation of rye (Secale cereale L.) allelochemical in field soils byAcinetobacter calcoaceticus: III

Acinetobacter calcoaceticus, a gram-negative bacterium isolated from field soil, was found to be responsible for the biotransformation of 2(3H)-benzoxazolinone (BOA) to 2,2-oxo-1,1-azobenzene (AZOB). Experiments were conducted to evaluate the transformation of BOA to AZOB by this microbe in sterile and nonsterile soil. Transformation studies with soils inoculated withA. calcoaceticus indicated that the production of AZOB increased linearly with the concentration of BOA in sterile soil and showed a quadratic trend in nonsterile soils. This also indicated that all soil types studied for the transformation experiments might containA. calcoaceticus capable of the conversion of benzoxazolinones.     

β-Sitosteryl (6'-O-linoleoyl)-glucoside of soybean (Glycine max L.) crude extract inhibits Y-family DNA polymerases

In the screening of selective DNA polymerase (pol) inhibitors, we isolated an acylated steryl glycoside, β-sitosteryl (6'-O-linoleoyl)-glucoside (compound 1), from the waste extract of soybean (Glycine max L.) oil. This compound exhibited a marked ability to inhibit the activities of eukaryotic Y-family pols (pols η, ι and κ), which are repair-related pols. Among mammalian Y-family pols, the activity of mouse pol κ was most strongly inhibited by compound 1, with an IC(50) value of 10.2 μM. On the other hand, compound 1 had no effect on the activities of other eukaryotic pols such as A-family (pol γ), B-family (pols α, δ, and ε), or X-family (pols β, λ and terminal deoxynucleotidyl transferase) pols. In addition, compound 1 had no effect on prokaryotic pols or other DNA metabolic enzymes such as calf primase of pol α, T7 RNA polymerase, T4 polynucleotide kinase, or bovine deoxyribonuclease I. Compound 1 consists of 3 groups: β-sitosteryl (compound 2), linoleic acid (compound 3), and D-glucose (compound 4). Compound 3 inhibited the activities of all mammalian pols tested, but compounds 2 and 4 did not have any effect on the tested pols. Kinetic studies showed that the inhibition of pol κ activity by compound 1 was noncompetitive with both the DNA template-primer and nucleotide substrate, whereas compound 3-induced inhibition was competitive with the DNA template-primer and noncompetitive with the nucleotide substrate. The relationship between the structure of compound 1 and the selective inhibition of eukaryotic Y-family pols is discussed.     

Nutritive Evaluation of the Bambara Groundnut Ci12 Landrace [Vigna subterranea (L.) Verdc. (Fabaceae)] Produced in C?te d’Ivoire

The nutritional evaluation of the Bambara groundnut Ci12 landrace (Vigna subterranea (L.) Verdc.) seeds produced in Côte d’Ivoire shows a 19% content of protein, containing all the essential amino acids with tryptophan as the limiting amino acid, a total dietary fiber level of 10%, with a low soluble fraction content, and a fat content of 1.4%, with a high proportion of total unsaturated fatty acids (61%) of which 36% were n-6 fatty acids. This legume contains phosphorus, as the major mineral, followed by magnesium and calcium, and trace elements (iron, copper and zinc). It is characterized by the same amount of α-tocopherol and antioxidant capacity as common legumes. The high concentration of essential amino acids, n-6 fatty acids and minerals, mainly Fe, in the Ci12 landrace of Bambara groundnut indicates that this local legume has the potentiality to improve the nutritional status in Côte d’Ivoire and it could be regarded as a nutrient dense food.     

Camelina (Camelina sativa L.) oil as a biofuels feedstock: Golden opportunity or false hope?

Camelina (Camelina sativa L.) is a promising sustainable alternative energy crop belonging to the Brassicaceae (mustard) family. Camelina has several favorable agronomic characteristics which give it potential to significantly enhance domestic biofuels production. With high seed oil content as well as high yield of oil per hectare, camelina can be efficiently processed into high quality renewable fuels such as biodiesel (fatty acid methyl esters) as well as renewable diesel and jet fuels using existing technologies. This review summarizes the attributes of camelina along with conversion of the lipid fraction into advanced renewable biofuels.     

固相萃取-高效液相色谱法检测上海青(Brassica chinensis L.)中鱼藤酮的残留动态

[目的]建立固相萃取-高效液相色谱-紫外(SPE-HPLC-UV)检测上海青中鱼藤酮的分析方法,对上海青中鱼藤酮的含量进行动态分析.[方法]样品先经乙腈提取,随后在乙腈提取液中加入氯化钠,盐析后过Florisil固相萃取柱富集净化,再用正己烷-乙醚(体积比3∶7)洗脱,最后以乙腈-水(体积比6∶4)为流动相,在290 nm下用高效液相色谱检测分析上海青中鱼藤酮的含量.[结果]该方法稳定可靠,检测物在0.05～10 mg/L范围内线性关系良好.在0.5～5 mg/kg范围内,平均加标回收率为85.9％～86.3％,检出限为0.05 mg/kg.田间推荐剂量和2倍推荐剂量分别施药,鱼藤酮在上海青中的原始沉积量分别为6.26、18.34 mg/kg.[结论]该化合物在田间降解速率快,在上海青中的半衰期分别为11.2、11.1h.     

(1S,2R,4S,5S)-angelicoidenol-2-o-β-d-glucopyranoside—A moose deterrent compound in Scots pine (Pinus sylvestris L.)

Hydrophilic extracts of Scots pine (Pinus sylvestris L.) twigs have been investigated for palatability to moose in feeding experiments. The predominant repellent effect was observed from the 2-O--d-glucopyranoside of the monoterpene (1S,2R,4S,5S)-angelicoidenol. Of other isolated and tested substances, only taxifolin-3-O--d-glucopyranoside had a deterring effect. One fraction-containing mainly aliphatic compounds-also had a strong effect, but the effect was lost after further fractionation. Tannin-containing fractions had no effect. Angelicoidenol glucoside has not previously been reported fromP. sylvestris. The results are discussed in view of phenols as defense compounds.     

Changes in Specific Gravity and Equilibrium Moisture Content in Heat-Treated Fir (Abies nordmanniana subsp. bornmülleriana Mattf.) Wood

The goal of this study was to determine the changes in specific gravity and equilibrium moisture content of fir (Abies nordmanniana subsp. bornmülleriana Mattf.) wood after heat treatment at different temperatures and durations. In this study, the effects of three different temperatures and three different durations were investigated. The temperatures were 170, 190, and 210°C, and the durations were 4, 8, and 12 h. The equilibrium moisture contents of the heat-treated specimens were determined at 20°C at relative humidities of 35, 50, 65, 80, and 90%, and the results were compared with control specimens. The results indicated that increasing temperatures increased the weight loss of the specimens. With respect to dimensional stabilization, the heat-treated specimens had lower equilibrium moisture contents than did the control specimens.     

Fatty acid composition of maturingVernonia anthelmintica (L.) Willd. seeds. dihydroxyoleic acid—A possible precursor of epoxyoleic acid

Quantitative measurements of epoxyoleic acid and co-occurring fatty acids in maturingVernonia anthelmintica (L.) Willd. seeds were made to elucidate partially the mode of epoxyoleic biosynthesis. Free (+)threo-12,13-dihydroxy-cis-9-octadecenoic acid was the major component at an intermediate maturation stage, and is believed to be dehydrated to free epoxyoleic acid before incorporation into glycerides. Presented before the Division of Biological Chemistry, Am. Chem. Soc. meeting in St. Louis, Mo., 1961. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Highly unsaturated fatty acid synthesis in marine fish: Cloning, functional characterization, and nutritional regulation of fatty acyl Δ6 desaturase of Atlantic cod (Gadus morhua L.)

This study reports the cloning, functional characterization, tissue expression, and nutritional regulation of a Δ6 fatty acyl desaturase of Atlantic cod (Gadus morhua). PCR primers were designed based on the sequences of conserved motifs in available fish desaturases and used to isolate a cDNA fragment from cod liver, with full-length cDNA obtained by rapid amplification of cDNA ends. The cDNA for the putative desaturase was shown to comprise 1980 bp, including a 261-bp 5′-UTR, a 375-bp 3′-UTR, and an ORF of 1344 bp that specified a protein of 447 amino acids. The protein sequence included three histidine boxes, two transmembrane regions, and an N-terminal cytochrome b₅ domain containing the heme-binding motif HPGG, all characteristic of microsomal fatty acyl desaturases. The cDNA displayed Δ6 desaturase activity in a yeast expression system. Quantitative real-time PCR assay of gene expression in cod showed that the Δ6 desaturase gene was expressed highly in brain, to a slightly lesser extent in liver, kidney, intestine, red muscle, and gill, and at much lower levels in white muscle, spleen, and heart. The expression of the Δ6 desaturase gene did not appear to be under significant nutritional regulation, with levels in liver and intestine being barely altered in fish fed a vegetable oil blend, in comparison with levels in fish fed fish oil. This was reflected in enzyme activity, as hepatocytes or enterocytes showed very little highly unsaturated FA biosynthesis activity irrespective of diet. Further studies are required to determine why the Δ6 desaturase appears to be barely functional in cod under the conditions tested.     

Lipid metabolism and tissue composition in Atlantic salmon (Salmo salar L.)—Effects of capelin oil, palm oil, and oleic acid-enriched sunflower oil as dietary lipid sources

Triplicate groups of Atlantic salmon (Salmo salar L.) were fed four diets containing different oils as the sole lipid source, i.e., capelin oil, oleic acid-enriched sunflower oil, a 1∶1 (w/w) mixture of capelin oil and oleic acid-enriched sunflower oil, and palm oil (PO). The β-oxidation capacity, protein utilization, digestibility of dietary fatty acids and fatty acid composition of lipoproteins, plasma, liver, belly flap, red and white muscle were measured. Further, the lipid class and protein levels in the lipoproteins were analyzed. The different dietary fatty acid compositions did not significantly affect protein utilization or β-oxidation capacity in red muscle. The levels of total cholesterol, triacylglycerols, and protein in very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL), and plasma were not significantly affected by the dietary fatty acids. VLDL, LDL, and HDL fatty acid compositions were decreasingly affected by dietary fatty acid composition. Dietary fatty acid composition significantly affected both the relative fatty acid composition and the amount of fatty acids (mg fatty acid per g tissue, wet weight) in belly flap, liver, red and white muscle. Apparent digestibility of the fatty acids measured by adding yttrium oxide as inert marker, was significantly lower in fish fed the PO diet compared to the other three diets.     

Dietary n−3 long-chain polyunsaturated fatty acid deprivation, tissue lipid composition, ex vivo prostaglandin production, and stress tolerance in juvenile dover sole (Solea solea L.)

Larval Dover sole fed an Artemia diet supplemented with n−3 long-chain (C₂₀+C₂₂) polyunsaturated fatty acids (PUFA) are known to be more resistant to low-temperature injury. Here we explore the relationship between tissue fatty acid composition and tolerance of stressful environmental conditions over the larval and early juvenile periods. Artemia nauplii supplemented with n−3 long-chain PUFA-deficient and PUFA-enriched oil emulsions were fed to two groups of larvae. Whole body tissue samples from the resulting PUFA-deficient and-enriched juveniles possessed 12.1 and 21.9% n−3 long-chain PUFA, respectively. These differences were at the expense of C₁₈ PUFA, while proportions of saturated fatty acids, monousaturated fatty acids, and total PUFA were unaffected. Brain and eye tissues from the PUFA-deficient fish contained lower levels of 22∶6n−3, known to be important for optimal nervous system function, incorporation instead a range of fatty acids of lower unsaturation. PUFA-deprived juveniles showed substantially greater mortality when exposed to a combination of low temperature and low salinity, as well as to high temperature and to hypoxia. After adaptation to the different diets, both dietary groups were fed a common formulated feed high in n−3 long-chain PUFA. Tissue PUFA in both groups progressively increased to the same high value, with a consequent loss of the differences in cold-susceptibility. These correlated changes support a link between dietary manipulation of n−3 long-chain PUFA and development of a stress-sensitive phenotype. PUFA deprivation had no detectable effect upon static hydrocarbon order of purified brain membranes (as assessed by fluorescence polarization) but was associated with an increase in the whole-body content of prostaglandins. We conclude that susceptibility to environmental stress is responsive to dietary n−3 long-chain PUFA manipulation, possibly due to altered tissue development or the overproduction of eicosanoids.     

美国化学文摘(C.A.)的查阅

1、文摘杂志的作用随着科学技术事业的蓬勃发展,特别是由于化学化工事业在国民经济中的特点和地位,因而化学化工文献具有种类多、数量大、较分散的特点。为了及时地将大量分散的文献资料加以搜集、摘录并分类组织整理起来,以便查阅参考,于是就产生了我们常知的文摘杂志。它能及时地反映化学化工方面的新成就及情报。具有资料丰富,涉及面广,检索方便的特点。读者可以利用自己熟悉的文字来进行查阅,从而为我们了解各国在化学化工方面的科学实验和生产发展情况,促进我们的工作提供了较为方便的条件。     

美国化学文摘(C.A.)的查阅(三)

摘文的阅读及取舍标准根据各种索引的介绍及对其熟练的运用,我们往往可由一个课题、项目及所需查阅的内容从索引中查得几个、几十个甚至几百个文摘号,按照这些文摘号即可去查阅C.A.的摘文,进行初步阅读。但必须指出,摘文的功用仅在于介绍原文的梗概,因此在阅读C.A.摘文时,往往要根据课题的目的要求来决定资料的取舍及是否需要阅读原文。这是因为由摘文所得的仅为一概貌,还不能完全作为依据,再加上文摘摘录者的看法与查阅者的要求未必完全一致,查阅者可能认为是重要的关键内容,未必尽为摘录者摘入,加以索引也未必就十分完美,因而通