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Said A. Hassan, Eman S. Elzanfaly, Salem Badr A. El-Zeany and Maissa Y. Salem

Abstract

Two methods were developed for separation and quantitation of amlodipine (AML) and atorvastatin (ATV) in the presence of their acidic degradation products. The first method was a simple isocratic RP-HPLC method while the second was capillary electrophoresis (CE). Degradation products were obtained by acidic hydrolysis of the two drugs and their structures were elucidated for the first time by IR and MS spectra. Degradation products did not interfere with the determination of either drug and the assays were therefore stability-indicating. The linearity of the proposed methods was established over the ranges 1-50 μg mL-1 for AML and ATV in the HPLC method and in the range of 3-50 and 4-50 μg mL-1 for AML and ATV, respectively, in the CE method. The proposed methods were validated according to ICH guidelines. The methods were successfully applied to estimation of AML and ATV in combined tablets.

Open access

Saïd A. El-Hassan, Simon R. Gowen and Barbara Pembroke

Abstract

Trichoderma hamatum (Bonord.) Bainier was evaluated for its antagonistic potential against Fusarium oxysporum Schlecht. emend. Snyder and Hansen sp. lentis, the causal agent of vascular wilt disease of lentil (Lens culinaris Medikus). Hyphal interactions on Petri plates resulted in an increase in the number of conidial spores and an increase in the vegetative growth of T. hamatum, and a decrease in the hyphal formation and sporulation of F. oxysporum f. sp. lentis. Electron and light microscopical observations suggested that hyphae of T. hamatum established aggressive contact and attachment with the hyphae of the pathogen. Growing in parallel, coiled densely and tightly, T. hamatum may penetrate those of the pathogen hyphae causing collapse due to the loss of turgor pressure. The cellulolytic enzymes produced by T. hamatum presented sufficient characteristics for its antifungal activity in the hyphae hydrolysis and competition process. In growth room and glasshouse experiments, the addition of the conidial suspension of T. hamatum or its culture filtrate to soil, significantly (p ≤ 0.05) reduced development and spore germination of F. oxysporum. In the rhizosphere, T. hamatum occupied the same ecological niches (rhizosphere, roots, and stems) parasitizing F. oxysporum f. sp. lentis. Treatments using T. hamatum delayed the time of infection by F. oxysporum, promoted the growth, and increased the dry weight of a susceptible variety of lentil (cv. Precoz). The percent of mortality was reduced to 33 and 40% when using T. hamatum and its filtrate, respectively, compared to 93% in the control treatment during the 65 days of growing in loam/sand (2:1 vol/vol) under glasshouse conditions. Plant colonization results indicate that T. hamatum and its filtrate significantly (p ≤ 0.05) reduced development of the pathogen in the vascular tissue of lentil to < 30 and < 40% stem colonization, respectively, compared to 100% in the plant pathogen control. Our results suggest that potential biocontrol mechanisms of T. hamatum towards F. oxysporum f. sp. lentis were antibiosis by production of antifungal enzymes, complex mechanisms of mycoparasitism, competition for key nutrients and/or ecological niches, growth promotion, and a combination of these effects. This study results hold important suggestions for further development of effective strategies of the biological control of Fusarium vascular wilt of lentil.

Open access

Esmat A. Hassan, Ahmed M.S. Hussein and Azza A.A. Hussein

Abstract

This study aimed to produce a baked dietary product (pate) enriched with broccoli florets that were sprayed in the field with methionine. Treated broccoli florets were separately stuffed in pate at three levels (5, 10 and 15%, w:w) in the form of minced, steam blanched and fried broccoli florets. A significant increase in reduced glutathione content was observed in the methionine-treated broccoli florets compared to methionine-untreated broccoli florets during processing to minced, steam blanched or as fried with butter. The pate stuffed with methionine-treated broccoli florets at different levels had higher fiber and protein contents if compared to control sample (not stuffed pate). Stuffing the processed pate had no effect on the estimated rheological properties, color attributes, baking tests and organoleptic properties. Increasing the ratio of stuffed methionine-treated broccoli florets increased loaf weight and decreased crumb moisture. The results revealed that stuffing pate with methionine-treated broccoli florets had enriched the nutritive value and baking quality. Generally, pate stuffed with methionine-treated broccoli florets (5:15%) did not significantly affect technological, rheological, sensory quality of pate and improved its nutritional values.

Open access

Said El Kurdi, Dina Abu Muaileq, Hassan A. Alhazmi, Mohammed Al Bratty and Sami El Deeb

Abstract

HPLC stationary phases of monolithic and fused core type can be used to achieve fast chromatographic separation as an alternative to UPLC. In this study, monolithic and fused core stationary phases are compared for fast separation of four fat-soluble vitamins. Three new methods on the first and second generation monolithic silica RP-18e columns and a fused core pentafluoro-phenyl propyl column were developed. Application of three fused core columns offered comparable separations of retinyl palmitate, DL-α-tocopheryl acetate, cholecalciferol and menadione in terms of elution speed and separation efficiency. Separation was achieved in approx. 5 min with good resolution (Rs > 5) and precision (RSD ≤ 0.6 %). Monolithic columns showed, however, a higher number of theoretical plates, better precision and lower column backpressure than the fused core column. The three developed methods were successfully applied to separate and quantitate fat-soluble vitamins in commercial products.

Open access

M.F. Mahmoud, M.A.M. Osman, M.A.M. El-Hussiny, A.A. Elsebae, S.A. Hassan and M. Said

Abstract

The study was carried out at two experimental farms in Ismailia Governorate, Egypt, during season of 2015 and 2016. GF-120 (Conserve® 0.024% CB) was selected in this study to evaluate its efficacy for controlling the peach fruit fly, Bactrocera zonata (Saunders) and the Mediterranean fruit fly, Ceratitis capitata (Wied.), on mango fruits by using partial bait spray and spots method. GF-120 was used as low environmental impact method and new way to control B. zonata and C. capitata, compared with malathion 57%, as traditional insecticide. During both seasons, data revealed that the number of C. capitata captured weekly from different treatments and untreated plots was higher than the number of B. zonata captured in both seasons of experiment. Data revealed that the number males of B. zonata and C. capitata captured weekly from sticky traps were lower in trees treated with GF-120 than malathion and untreated plots. In the farm of Faculty of Agriculture, Suez Canal University, the lowest percentages of infestation of both dropping and setting fruits per tree were recorded in plots treated with GF120 (spots), with an average of 25.14 and 17.022% for dropping fruits and 2.2 and 2.0% for setting fruits for 2015 and 2016 season, respectively. Data indicated that the all tested formulation under field condition caused significant reduction in the rate of infestation from 54.92 to 81.79 for both dropping and setting fruits. The lowest percentages of infestations in the private farm of both dropping and setting fruits per tree were recorded in GF-120 (spray treatment), with an average of 20.0, 12.12 for dropping fruits and 3.4 and 4.0 for setting fruits for 2015 and 2016 seasons, respectively.