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101.
Abstract

Methods used to estimate the CO2 emission from soil commonly measure the total CO2 flux. To be able to quantify the net CO2 emission from cultivated peat soils there is a need to distinguish between soil organic matter-derived CO2 respiration and plant-derived respiration. In this investigation we used the root exclusion method to separate the plant-derived respiration from total CO2 emission. The plant-derived contribution was estimated to be between 27 and 63% of total CO2 emission depending on soil type and season. We also found a relationship between soil temperature, biomass growth and CO2 efflux, which can be used to estimate plant-derived respiration. Due to the priming effect the root exclusion method is less reliable late in the season.  相似文献   
102.

Rhizoremediation is a complex type of green clean-up technology that involves both plants and the rhizosphere-associated microorganisms to decompose hazardous compounds. The success of the strategy strongly depends on plant tolerance towards the pollutant, as well as plant's interactions with the rhizospheric microbes. The microorganisms may be stimulated by the secreted root exudates, which results in an increased breakdown of contaminants in the rhizosphere. The main goal of this study was to establish a potential rhizoremediation combination for a diesel-polluted site. Inoculation of plant roots or seeds with indigenous rhizospheric populations is a common approach in the rhizoremediation. However, we introduced hydrocarbon-degrading consortia (M10, R3, and K52) that were previously isolated from crude oil-contaminated soil instead of indigenous microbes. Bioaugmentation with these petroleum degraders was applied to screen four high biomass crop species (Indian mustard, alfalfa, high erucic acid rapeseed, HEAR, and low erucic acid rapeseed, LEAR) for their tolerance towards diesel oil. At no pollution, a promoting effect of M10 bacteria could be observed on germination and root elongation of all plant species. Moreover, M10 consortiums increased the germination index at 6,000 mg diesel oil per kilogram dry soil in the case of Indian mustard, alfalfa, and HEAR. The latter species was found to increment its dry weight upon bioaugmentation with M10 bacteria and all diesel oil treatments (6,000 and 24,000 mg diesel oil per kilogram dry soil). The initial results indicate HEAR and the M10 bacterial consortium as a promising plant–microbe tandem for a long-term rhizoremediation process.

  相似文献   
103.
This, partly retrospective study, was designed to determine the seroprevalence of Schmallenberg virus (SBV), a new Orthobunyavirus first reported in Germany in late 2011, in domestic ruminants from the Middle Black Sea, West, and Southeast regions of Turkey. An indirect enzyme-linked immunosorbent assay was used to screen serum samples collected from slaughterhouse animals between 2006 and 2013. The overall seroprevalence was 335/1,362 (24.5 %) with 325/816 (39.8 %), 5/307 (1.6 %), 3/109 (2.8 %), and 2/130 (1.5 %) recorded in cattle, sheep, goats, and Anatolian water buffalo, respectively. This is the first study to demonstrate the presence of antibodies to SBV in Turkish ruminants; it indicates that cattle are more susceptible to infection than sheep, goats, or buffalo and that exposure of domestic ruminants to SBV in Turkey may have occurred up to 5 years prior to the first recorded outbreak of the disease in 2011.  相似文献   
104.
To help in the development of Sunn Pest-resistant transgenic plants employing protease or α-amylase inhibitors, midgut hydrolytic enzymes of Sunn Pest (Eurygaster integriceps, Put.) (Heteroptera: Scutelleridae) were identified and characterized biochemically. We observed levels of very low proteolytic activity of trypsin (3 nmoles/min/mg), elastase (0.66 nmoles/min/mg) and leucine aminopeptidase-like (14.4 nmoles/min/mg) proteases, but no chymotrypsin and papain-like activity. Proteolytic activities were insensitive to inhibition by soybean trypsin inhibitor (SBTI) and aprotinin, but were inhibited to varying degrees (40–100%) by the synthetic protease inhibitors PMSF, TPCK, CdCl2 and CuCl2. Compared to proteolytic activity, significantly higher amylolytic activity (4.45 mmoles/min/mg) was observed. Αlpha-amylase activity was found to be resistant to inhibition by bean and chickpea α-amylase inhibitors, and only slightly inhibited by wheat (36.9 ± 1.8%) and maize (40.2 ± 2.8) α-amylase inhibitors. Here, we report on the biochemical properties of digestive enzymes from Sunn Pest midgut, and their inhibition patterns by several synthetic and natural hydrolytic enzyme inhibitors.  相似文献   
105.
The objective of the present work was to evaluate the effects of three different rates of long chain n-3 polyunsaturated fatty acid (LC n-3 PUFA) on the sperm number of Astacus leptodactylus. The experiment was carried out with the four following treatments: control group (not supplemented LC n-3 PUFA), D1 (1 %), D2 (2 %) and D3 (3 %). The sperm number of A. leptodactylus was counted; the reproductive system was weighted; and the macroscopical analysis of the testes and vasa deferentia (DVD) were conducted. In addition, gonado-somatic index (GI) and testes index (TI) were also calculated. The results showed that there was a significant difference between the crayfish fed LC n-3 PUFA supplemented diets (D1, D2, D3) and control in mean sperm number (P < 0.05). The highest sperm number was found for the crayfish fed D3 (6.27 ± 0.14 × 108 sperm/distal vas deferens section). The results also showed that the reproductive system of the crayfish fed D3 and D2 was significantly heavier than that of the crayfish fed the control and D1 (P < 0.05). On the other hand, there was not a significant difference in the testes weight and vasa deferentia weight between the crayfish fed the control and D1, and between the crayfish fed D2 and D3 (P < 0.05). GI of the crayfish fed D3 and D2 was significantly higher than that of the crayfish fed control and D1 (P > 0.05), but there was not a significant difference in the TI of the crayfish fed control, D1, D2 and D3 (P > 0.05). In conclusion, diets containing different levels of LC n-3 PUFA significantly increase the sperm number of A. leptodactylus, and they are crucial for the production of higher number of sperm in this species.  相似文献   
106.
The fatty acid composition and oxidative stability of fish oil and syrups available in the Turkish retail market were examined in this study. The major saturated fatty acids in capsules and syrups were palmitic acid (16:0) and stearic acid (18:0). The monounsaturated fatty acid contents of fish oil products have very different results (10.71–50.46%). The results show that the label claims for total omega-3, eicosapentaenoic acid, and docosahexaenoic acid presented a reasonable accuracy for the examined products, but it was noted that some of the results showed a considerable difference with the labels.

The free fatty acid level in fish oil products was generally low (0.13–1.95% of oleic acid). Peroxide value of all examined products was below the limit of 10 meq kg?1 oils for edible oil as indicated in Codex (1999). It was detected that the p-Anisidine value of fish oil capsules (5.36–8.90) was considerably lower than for fish oil syrups (21.86–26.74). According to our results, the totox value of fish oil capsules evaluated in this study (7.08–17.35) was within acceptable limits. However, fish oil syrups (34.72–38.06) highly exceeded the upper tolerable limit (26).  相似文献   
107.
In the present study,Cnaemidophorus rhododactyla (Denis & Schiffermüller) (Lepo Pterophoridae) was noted for the first time as a pest ofRosa spp. in Turkey. The larva ofC. rhododactyla makes a cavity by feeding in the flower-bud and destroys at least 60% of the mass of the flower-bud. There are approximately 12 species ofRosa in Erzurum and Kars provinces, butRosa dumalis Bechst. andR. subcanina L. suffered more damage than the otherRosa species. One species of Tachinidae (Diptera) —Pseudoperichaeta palesoidea (Robineau-Desvoidy), and two species of Ichneumonidae (Hymenoptera) —Sinophorus turionus (Ratz.) andScambus brevicornis Gravenhorst, were reared as larval parasitoids ofC. rhododactyla. C. rhododactyla is a new host record for these parasitoids. Additionally,S. turionus is a new record for the Turkish fauna.  相似文献   
108.
109.
Antioxidant activity of pressurized low polarity water (PLPW) extracts of cow cockle seed and extraction residues were determined using DPPH, ABTS, and FRAP assays. The effect of extraction conditions (temperature (125, 150 and 175 °C) and time) on the antioxidant activity and the relationship amongst the antioxidant activity and extract composition (total phenolics and saponin content) were determined. The antioxidant activity of PLPW extracts increased with extraction temperature. Increasing activity with time was also observed at 175 °C. PLPW extraction residues had the highest activity suggesting antioxidant compounds were not completely extracted by PLPW. Antioxidant activity correlated well with total phenolics content of samples (R 2 ≥ 0.94), however no correlation was observed with the saponin content. A strong correlation was observed between the antioxidant activity values obtained using different methods (R 2 ≥ 0.94). These results point to the potential of PLPW extraction as a method to modify the activity of biological materials for the production of customized extracts.  相似文献   
110.
Tydén, E., Löfgren, M., Pegolo, S., Capolongo, F., Tjälve, H., Larsson, P. Differential gene expression of CYP3A isoforms in equine liver and intestines. J. vet. Pharmacol. Therap.  35 , 588–595. Recently, seven CYP3A isoforms – CYP3A89, CYP3A93, CYP3A94, CYP3A95, CYP3A96, CYP3A97 and CYP129 – have been isolated from the horse genome. In this study, we have examined the hepatic and intestinal gene expression of these CYP3A isoforms using TaqMan probes. We have also studied the enzyme activity using luciferin‐isopropyl acetal (LIPA) as a substrate. The results show a differential gene expression of the CYP3A isoforms in the liver and intestines in horses. In the liver, CYP3A89, CYP3A94, CYP3A96 and CYP3A97 were highly expressed, while in the intestine there were only two dominating isoforms, CYP3A93 and CYP3A96. The isoform CYP3A129 was not detected in the liver or the intestine, although this gene consists of a complete set of exons and should therefore code for a functional protein. It is possible that this gene is expressed in tissues other than the liver and intestines. In the intestine, both CYP3A96 and CYP3A93 showed the highest gene expression in the duodenum and the proximal parts of the jejunum. This correlated with a high protein expression in these tissues. Studies of the enzyme activity showed the same Km for the LIPA substrate in the liver and the intestine, while the maximum velocity (Vmax) in the liver was higher than in the intestine. Our finding of a differential gene expression of the CYP3A isoforms in the liver and the intestines contributes to a better understanding of drug metabolism in horses.  相似文献   
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