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  • Author or Editor: M. A. El-Tayeb x
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A study on the germination of five Vicia faba cultivars exposed to polyethylene glycol-induced water stress indicated that cv Giza 40 showed the highest germination capacity and cv Giza 667 the lowest. The effect of low soil water content was studied on the plant growth, photosynthetic pigment content, organic solutes, relative water content (RWC), lipid peroxidation, membrane stability index (MSI), and the catalase (CAT) and peroxidase (POX) activity in the leaves of 21-day-old Vicia faba cv Giza 40 and cv Giza 667 plants. With respect to dry weight (DW), drought caused a greater decrease in cv Giza 667 than in cv Giza 40, indicating that cv Giza 40 was more tolerant of low soil water content. Drought decreased the Chl a, Chl b and carotenoid contents and the Chl a/b and carotenoid/Chl a+b ratios in the leaves of cv Giza 667, while in cv Giza 40 a significant increase in these pigment parameters was observed under drought stress. Drought caused a decrease in RWC and MSI and an increase in the lipid peroxidation level and in the catalase (CAT) and peroxidase (POX) activity in both the cultivars, but the decline in RWC and MSI and the increase in lipid peroxidation level in response to drought stress were greater in cv Giza 667 than in cv Giza 40. The CAT and POX activities were higher in Giza 40 than in Giza 667 under both control and drought conditions. Drought induced the accumulation of soluble sugars, soluble proteins, free amino acids and proline in both cultivars. However, this accumulation was lower in cv Giza 667 than in the more tolerant cv Giza 40. These results indicate that cv Giza 40 showed better protection against drought-induced oxidative stress through higher CAT and POX activities and osmolyte concentrations than cv Giza 667.

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The effect of water stress on the germination, seedling growth, organic solutes, peroxidase pattern and peroxidase activity of different Vicia faba lines was studied. Studies on germination in polyethylene glycol and in soil indicated that lines such as Line 2/4 which were able to germinate under water stress caused by high concentrations of polyethylene glycol, were also able to germinate and grow in soil with a low water content. While the fresh and dry masses of all the lines were markedly decreased as the water stress level increased, Line 2/4 exhibited higher dry matter than the other lines tested. Pigment contents were more or less unchanged in some lines (102, 159 and 2/4) but increased in others (67 and 103) as the stress level increased. In general, the soluble sugar, soluble protein, free amino acid and proline contents in the shoots and roots of all the tested lines progressively increased as the stress level increased. These values were higher in the plant shoots than in the roots except for Line 2/4, which was the only one that could be grown at 30 % field capacity, and which accumulated soluble sugars and free amino acids in the roots rather than in the shoots Differences in the peroxidase (POX) pattern were found among the roots and shoots of the tested lines. Under drought stress, the number and staining intensity of the POX bands as well as the POX activity were lower in the shoots than in the corresponding unstressed control plants, especially in the sensitive line (159). In the plant roots, while the number of peroxidase isoenzymes and peroxidase activity were reduced in the sensitive line, they were unaffected in the resistant line (2/4).

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Pharmaceutical industry concerned recently with eco-friendly analytical methods to reduce the environmental pollution. The using of toxic organic solvents for the analysis of drugs is critical. In the current work, several simple and less costly approaches such as micellar and/or cyclodextrin liquid chromatography were discussed. A new eco-friendly and simple chromatographic analysis of the ternary mixture of amiloride hydrochloride (AM), atenolol (AT), and hydrochlorothiazide (HZ) in urine by hydroxypropyl-beta-cyclodextrin (HP-β-CD) bonded stationary phase was investigated. The experimental conditions were optimized and validated based on International Conference on Harmonization (ICH) Q2R1 guidelines to detect analytes by isocratic mobile phase of phosphate buffer (5.0 mmol L−1, pH 7.0) in the presence of 0.5 mL min−1 flow rate, 25.0 °C, and 280 nm. Linearity, accuracy, and precision were found to be acceptable over the concentration range of 0.05–20.0 μg mL−1 for AM, 0.05–50.0 μg mL−1 for AT and 0.05–50.0 μg mL−1 for HZ. The proposed method was precise, selective, and sensitive enough for the routine analysis of ternary mixture at therapeutic urine levels. The inclusion complexation and the appendant hydroxyl groups of HP-β-CD were considered the main reasons for assisting in adequate separation of the drugs. On the other hand, the presence of kosmotropic phosphate ions could solubilize the protein and could strengthen the selective inclusion of drugs inside HP-β-CD cavity. Urinary excretion studies showed that the detection of drugs is possible up to 24 h after their ingestion.

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