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41.
The aim of this study was to evaluate the effects of the fungicide flusilazole on somatic cells of Allium cepa. For evaluation of cytogenetic effects, root meristem cells of A. cepa were treated with 10, 20, 30 and 45 ppm (EC50 concentration) for 24, 48 and 72 h. The mitotic index and different types of chromosomal abnormalities such as bridges, stickiness and laggards were determined in both control and test groups. Acridine orange/Ethidium bromide double staining and fluorescence microscope was used to determine the stability of chromosome structure. Data obtained from staining process indicated that ratio of necrotic cells significantly increased by the flusilazole presoaking. The RAPD-PCR method was used and the higher doses treated-group (45 ppm) was more distant to the control group compare with others.  相似文献   
42.
Genotyping of Turkish grapevine (Vitis vinifera L.) germplasm was characterized by use of six highly polymorphic microsatellite loci (VVS2, VVMD5, VVMD7, VVMD27, VrZAG62, VrZAG79). In this study we aimed to clarify the relationships between homonymous varieties coming from different regions. Our results showed a large degree of genetic variability among most of the homonymous cultivars. The number of alleles per locus ranged from 10 to 21, and gene diversity (expected heterozygosity) values ranged from 0.85 to 0.93. Cultivars presenting the same names of Sergi karas? (sampled from ?anl?urfa and Gaziantep), Yediveren (sampled from ?anl?urfa, Gaziantep, and National Germplasm Repository Vineyard in Tekirda?) and Serpenek?ran (sampled from ?anl?urfa and Gaziantep) were clustered together, or very close to each other, in a phenogram. Moreover, the alleles at the six microsatellite loci analyzed were found to be similar in terms of base pairs within each of these three closely positioned varieties. However, all the other cultivars failed to show a suitable clustering pattern when comparing their DNA profiles and names. Similarly named cultivars were not generally grouped together in the phenogram. On the other hand, we detected a tendency for differently named homonymous grape cultivars to cluster together.  相似文献   
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44.
Plant Foods for Human Nutrition - This study aimed to optimize the extraction conditions for Sorbus umbellata (Desf.) Fritsch var. umbellata leaves to maximize the phenolic content and their...  相似文献   
45.
This study was designed to investigate the effect of feeding on the plasma disposition of triclabendazole (TCBZ) in goats following oral administration. A total of eight goats, aged 14–16 months and weighing 20–30 kg were used in this study. The animals were allocated into two groups (fasted and fed groups) of four animals each. The goats in fed group were fed ad libitum but the animals in fasted group were not fed 24 h before and 6 h after drug administration. Commercial oral drench formulation of TCBZ (Endex-K, 5%) was administered orally to animals in two groups at dose of 10 mg/kg bodyweight. Heparinized blood samples were collected between 1 and 192 h after treatment and the plasma samples were analysed by high performance liquid chromatography (HPLC) for TCBZ, TCBZ sulphoxide (TCBZ–SO), and TCBZ sulphone (TCBZ–SO2). Relatively very low concentration of TCBZ parent drug was detected between 2 and 48 h, but TCBZ–SO and TCBZ–SO2 metabolites were present between 2 and 192 h in the plasma samples of fed and fasted animals. Fasting significantly enhanced the plasma concentration of TCBZ and its metabolites. The availability of TCBZ, TCBZ–SO and TCBZ–SO2 in the plasma samples of fasted goats were markedly greater compared to those of fed goats. It was concluded that fasting decreases the digesta flow rate and prolongs the retention of the drug into the gastrointestinal tract, resulting in enhanced quantitative gastrointestinal absorption or systemic availability of TCBZ and its metabolites in fasted goats.  相似文献   
46.
Boron (B) is one of the essential nutrients for the growth of plants, but its high concentrations are toxic for plants. Thus, B toxicity is a big challenge in crop cultivation. Nitric oxide (NO) is a small signaling molecule that has cytoprotective roles in plants. We investigated whether exogenous sodium nitroprusside (SNP), which is a NO donor, may succeed to alleviate B-induced toxicity in wheat cultivars. Seedlings were grown for 10 days in a growth chamber at 25°C with 16 hr light–8 hr dark photo cycle. After high B application, the effects of SNP on growth parameters; electrolyte leakage (EL); changes in reactive oxygen species [contents of hydrogen peroxide (H2O2), malondialdehyde (MDA), and proline]; the activities of antioxidant enzymes [glutathione peroxidase (GSHPx), glutathione reductase (GR), and glutathione S-transferase (GST)] and nitrate reductase (NR); and low molecular weight organic acid (LMWOAs) contents and also chlorophyll and total carotenoid contents were investigated in both shoots and roots of two different wheat cultivars. All experiments were carried out in triplicate. 0.2 mM SNP application ameliorated the chlorophyll and total carotenoid contents, and growth parameters such as shoot length, root length, and fresh weight in both wheat cultivars exposed to B stress. SNP reduced the B-induced lipid peroxidation, EL, and proline and H2O2 content in wheat cultivars. SNP application also increased the activities of NR and antioxidant enzymes, including GSHPx, GR, and GST in wheat cultivars exposed to B toxicity. All of the tested LMWOAs including succinic, propionic, butyric, oxalic, formic, malic, malonic, and benzoic acids were increased by SNP treatment in the shoots and roots of both wheat cultivars exposed to B toxicity. In conclusion, results obtained from this study have demonstrated that interactive effects of SNP with B considerably reduced the toxic effects of B in wheat cultivars.  相似文献   
47.
Tomato products and especially concentrated tomato paste are important sources of antioxidants in the Mediterranean diet. Tomato fruit contain well-known antioxidants such as vitamin C, carotenoids, flavonoids, and hydroxycinnamic acids. The industrial processing of this fruit into tomato paste involves several treatments that potentially affect the final profile of antioxidants and other metabolites in the commercial product. Here we have used both biochemical and metabolomic techniques to assess the effect of each separate step in the industrial production chain starting from fresh fruit to the final tomato paste. Material was collected from five independent tomato paste production events spread over two successive years. Samples comprised the intact ripe fruits and semifinished products after fruit-breaking, separation of the pulp from skin and seeds, evaporation, and finally after canning and pasteurization. The effect of each processing step was determined by different types of analysis. First, the total antioxidant capacity and total phenolic content were determined by commonly used spectrophotometric methods. Second, individual antioxidants in the extracts were identified and compared using an HPLC with online antioxidant detection. Third, in each sample the levels of the major individual antioxidants present, i.e., vitamin C, phenolic compounds (such as rutin and chlorogenic acid), tocopherols, and carotenoids, were quantified. Fourth, an untargeted metabolomic approach using LC-QTOF-MS was used to identify those production steps that have the largest impact on the overall metabolic profile in the final paste as compared to the original fruits. This multifaceted approach has revealed that each processing step induces specific alterations in the metabolic profile, as determined by the different analysis procedures, and that in particular the fruit-breaking step and the removal of seed and skin significantly affect the levels of antioxidants and many other metabolites present in commercial tomato paste.  相似文献   
48.
In this study, the electron paramagnetic resonance (EPR) spin probe technique is applied as a detection method in the differentiation of irradiated and unirradiated wheat seeds. Two wheat cultivars, Kunduru and Bezostaya, were used. Aqueous solutions of 4-hydroxy-TEMPO (TANOL) spin probe prepared with a line-broadening agent, potassium ferricyanide, were used in all experiments. The EPR spectra of the samples were recorded against time. A decrease in the signal intensity and a change in the shape of the intensity-time curve (rehydration curve) were observed, depending on the applied level of irradiation. The ratio of the lipid and aqueous regions at the high field (mI = -1) line changes, depending on the dose of irradiation.  相似文献   
49.
This study was designed to examine the in vitro antimicrobial and antioxidant activities and the amount of total phenolics of the methanol extracts of Ballota rotundifolia L. and Teucrium chamaedrys C. Koch. In the case of antimicrobial activity tests, polar sub-fractions of the methanol extracts of plant species exhibited weakest antimicrobial activity when compared with the non-polar ones. While, non-polar sub-fraction of B. rotundifolia showed moderate activity against A. lwoffii, C. perfringens and the yeasts, T. chamaedrys performed excellent activity pattern against all of the tested microorganisms. The sub-fractions were also screened for their possible antioxidant activities by two complementary tests, namely DPPH free radical-scavenging and β-carotene/linoleic acid assays. Non-polar extracts of the plant species remained inactive in both test systems. On the other hand polar extracts showed remarkable antioxidant activities. In DPPH system, free radical scavenging effect of T. chamaedrys was measured as 18.00 ± 1.42 μg.mg−1. It is extremely important to point out that, polar sub-fraction of T. chamaedrys is found as effective as the positive control BHT. Non-polar sub-fraction of T. chamaedrys found to have the highest total phenolic amount (97.12 ± 1.28 μg/mg). Results obtained from this experiment confirm the relationship between the amount of phenolics and biological activities.  相似文献   
50.
Specific plants can remove salts from the soil and contribute to saline remediation in orchard intercropping. Determining the level of highest salinity that a salt-removing crop can withstand without reducing its yield is important for management. It is also important to know the critical hazardous level of saline irrigation water for the fruit trees.The objective of this study was to investigate the salt-removing capacity of purslane by studying different stress criteria and by tracking its salt removal from germination to harvest. Therefore, a pot experiment was performed by enhanced salinity levels.The results showed that purslane could cumulatively remove considerable amounts of salt from the soil if practical to cultivate as an intercrop all year round. In this regard, 6.5 dS m−1 can be concluded as the reasonable salinity level for the purslane managed to be intercropped in fruit orchards.  相似文献   
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