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The developmental time, survival, fecundity and life table parameters of the predacious mite, Lasioseius lindquisti Nasr and Abou-Awad were determined on seven different food types at 28±1° C and 70±5% RH. The food tested are, the eriophyid mite, Aceria dioscoridis (Soliman and Abou-Awad), the acarid mite, Rhizoglyphus robini Claparede, the two spotted spider mite Tetranychus urticae Koch, pollen grains of Ricinus communis L and Phoenix dactylifera L. as well as fungi of Fusarium oxysporum Snyder and Fusarium solani Snyder. Total developmental time of L. lindquisti female was shortest (7.0, 7.7, 7.2 and 8.0 days) on A. dioscoridis, pollen grains of P. dactylifera and both fungi F. solani and F. oxysporum, respectively. The total egg production rates were the highest on A. dioscoridis and pollen grains of P. dactylifera (62.7 and 46.6 eggs / ♀, respectively). A diet of A. dioscoridis showed a higher values of the net reproductive rate (Ro = 42.3375), intrinsic rate of increase (rm = 0.2902) and finite rate of increase (λ = 1.3367) per day than pollen grains of P. dactylifera and the fungus F. oxysporum. A diet of F. oxysporum fungus resulted the lowest total fecundity which resulted in the lowest the net reproductive rate (Ro = 17.9290), intrinsic rate of increase (rm = 0.1941) and finite rate of increase (λ = 1.2142)) per day for L. lindquisti. Rhizoglyphus robini, pollen grains of R. communis and F. solani fungus were considered as supplementary food for the predator L. lindquisti, since the predator able to feed and develop on above diets but failed to sustain oviposition. The sex ratio of the progeny was female biased (female / total = 0.68 and 0.62) when A. dioscoridis and pollen grains of P. dactylifera were provided to the predator. Lasioseius lindquisti failed to feed and develop on nymphs of T. urticae.

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The induction of resistance to charcoal rot disease caused by Macrophomina phaseolina (Tassi) Goidanich in sunflower (Helianthus annuus L.) was studied after seed treatments with coumarin (COU) and salicylic acid (SA) at three different levels (0.3, 1.0 and 3.0 mM). The priming of sunflower seeds with 0.3 mM COU or 1.0 mM SA resulted in decreased disease severity and offered about 50% protection and more than 80% reduction in the length of stem lesions under greenhouse conditions. Both COU and SA treatments induced the accumulation of soluble sugars and phytoalexins, as well as stimulating the activity of β-1,3-glucanase and chitinase.

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Abstract

Residues of the fungicides difenoconazole, propiconazole, cyflufenamid, and mandipropamid were determined in tomato fruit using acetonitrile for extraction and LC-MS/MS for quantification. Validation criteria include linearity range, the limit of detection (LOD) and limit of quantitation (LOQ), accuracy in terms of precision and trueness, and matrix effect were studied. The recovery rates of the method ranged from 91.8 to 106.3%. The precision of the method in terms of repeatability at one day (RSDr) and between three days (RSDR) ranged from 2.8 to 6.4% and from 4.3 to 7.6%, respectively, with good trueness from 92.2 to 96.4%. Matrix effects (suppression effects) ranged from 3.8% to 11.1%. The validated method was used to evaluate the dissipation kinetics of three different premix formulations: 30% EC (15% difenoconazole + 15% propiconazole), 14% DC (12.5% difenoconazole + 1.5% cyflufenamid), and 50% SC (25% difenoconazole + 25% mandipropamid) used on field tomatoes in Egypt. A first-order kinetic equation best describes residue dissipation. The calculated half-lives of difenoconazole, propiconazole, cyflufenamid, and mandipropamid were 2.01–2.27, 1.89, 1.97, and 1.71 days, respectively. The dissipation rate of difenoconazole did not differ significantly in the three premix formulations. Mandipropamid also dissipated faster compared to the other fungicides tested. The chronic dietary risk assessment results showed a minimal risk to adult Egyptian consumers. Waiting periods were advised for the safe consumption of tomatoes treated with the tested premix formulations.

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Summary

Reversed phase high-performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC)-spectrodensitometric methods have been developed and validated for the separation and quantitation of two binary mixtures: Ofloxacin (OFX) and dexamethasone (DXM) in eye preparation; ciprofloxacin hydrochloride (CIP) and hydrocortisone (HYD) in ear preparation. The linearity ranges of RP-HPLC methods were found to be (2.5–45 μg mL−1) for OFX, (2.5–50 μg mL−1) for DXM and (1–8 μg mL−1) for both CIP and HYD. The percentage recoveries/relative standard deviation (RSD) were found to be 100.36/1.38, 100.13/1.49, 99.98/0.61 and 100.28/1.27, respectively. The linearity ranges of TLC-spectrodensitometric methods were found to be (0.5–2 μg band−1), (0.5–3.5 μg band−1), (0.2–1.6 μg band−1), and (0.6–2 μg band−1) for OFX, DXM, CIP, and HYD, respectively. The percentage recoveries/RSD were found to be 99.98/1.06, 99.93/1.18, 99.74/1.27, and 99.94/1.54, respectively. A comparative study was conducted to show the advantages of the proposed methods which showed that the TLC-spectrodensitometric methods were simpler, more sensitive, and economic, while RP-HPLC methods were more precise and robust. The methods were validated in compliance with the ICH guidelines and were successfully applied for determination of the selected drugs in their laboratory-prepared mixtures and commercial dosage forms.

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Abstract

In this study, the mineralogical content of Abu Rusheid mylonite sample was investigated and revealed that the sample is essentially composed of quartz and feldspar (72.14% mass), muscovite (16.6% mass), and contains heavy economic polymetallic minerals of about 2.65% by mass. By studying the differences in the physical properties of this mineral content, a proposed flow sheet was set up to explain the successive physical upgrading steps for concentrating and separating the valuable minerals content and getting rid of the associated gangue minerals. Industrial, economic and strategic polymetallic minerals were identified at Abu Rusheid mylonite sample, including cassiterite, titanite, brass, kasolite, monazite, and uranothorite. A group of sulfide minerals also existed as pyrite, arsenopyrite, galena, and molybdenite in addition to the presence of fluorite and iron oxides bearing rare earth elements (REEs) and base metals. Using dry high intensity magnetic separation followed by wet gravity separation and flotation, three concentrates were obtained; heavy paramagnetic concentrate (monazite, columbite, brass, and jarosite), heavy diamagnetic concentrate (zircon, kasolite, uranothorite, cassiterite, and sulphide minerals) and muscovite concentrate for industrial uses. Physical processing of Abu Rusheid mylonite sample was carried out to produce high grade mineral concentrate used as a raw material for chemical treatment to extract economic elements that necessary for several industries.

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This work presents a comparative study on the development and validation of two analytical techniques applied for the simultaneous determination of hydrocortisone acetate (HCA), fusidic acid (FSA), methyl paraben (MPB), and propyl paraben (PPB) formulated as a topical cream. The first technique was thin-layer chromatography (TLC)–densitometric method, which was developed by separating the four components on silica gel 60 F254 using methylene chloride–methanol–benzene in the ratio of 10:2:5, v/v, as the developing system, followed by densitometric measurement of the bands at 240 nm. The second technique was the chemometric method using two models: principle component regression model (PCR) and partial least squares (PLS). The suggested techniques were validated in compliance with the International Conference on Harmonization (ICH) guidelines and were successfully applied for the determination of the quaternary mixtures as prepared synthetically in laboratory and in the commercial topical pharmaceutical formulation.

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Tomato crop in the Mediterranean Basin has been recently affected by the exotic pest Tuta absoluta (Meyrick), which is difficult to control due to its high reproduction rate and potential to develop resistance to insecticides. In this paper, the suitability and effectiveness of three predatory phytoseiid mites Cydnoseius negevi (Swirski and Amitai), Neoseiulus barkeri (Hughes) and Amblyseius largoensis (Muma), an indigenous species, were evaluated on larvae of T. absoluta under laboratory conditions. First instar larvae of T. absoluta proved to be possible food source for tested phytoseiid mites under laboratory conditions.

Females of C. negevi, A. largoensis and N. barkeri were able to feed and sustain oviposition on unfed, first instar larvae of T. absoluta. A diet of insect larvae provided the shortest oviposition period and adult longevity of C. negevi and A. largoensis, while N. barkeri showed the longest corresponding periods. The total and daily number of insect larvae consumed was significantly higher in N. barkeri than in A. largoensis and C. negevi. Likewise, N. barkeri laid significantly higher number of eggs (23.6 eggs / female) than that deposited by C. negevi and A. largoensis (2.5 and 3.9 eggs / female). The sex ratio of the progeny was female biased and ranged: (females / total=0.62-0.68%) when insect larvae were provided for females of C. negevi, A. largoensis and N. barkeri.

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Development, survival and reproduction of the generalist predatory mites, Amblyseius largoensis (Muma), Neoseiulus barkeri (Hughes), Typhlodromips swirskii (Athias-Henriot), Proprioseiopsis kadii (El-Halawany and Abdel-Samad) and Cydnosus negevi (Swirski and Amitai) were assessed when fed on eggs of Bactrocera zonata (Saunders) (Diptera: Tephritidae) as a factitious food. For N. barkeri and P. kadii, the development was faster, while the reproduction was higher in N. barkeri and A. largoensis than for P. kadii. Survival of immatures of T. swirskii and C. negevi was low on eggs of B. zonata and all failed to develop beyond the protonymphal stage.

A total of 35.4, 31.2 and 19.6 eggs per female, respectively, were obtained when N. barkeri, A. largoensis and P. kadii were fed B. zonata eggs. A diet of the peach fruit fly eggs provided the longest female longevity and highest mean total fecundity, which resulted in the highest net reproductive rate (Ro=34.61 and 32.78) and doubling time (DT=1.53 and 1.60) for N. barkeri and A. largoensis, respectively.

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The predatory mite Cosmolaelaps keni is a native laelapid mite in Egypt. Development and adult longevity durations as well as fecundity of C. keni reared on five types of prey, Bactrocera zonata, Spodoptera littoralis and Corcyra cephalonica eggs (as insects prey), Aceria dioscoridis and Caloglyphus rodriguez (as mites prey) were determined under laboratory conditions. Cosmolaelaps keni was able to feed, develop and sustain oviposition on all examined insect and mite species. The mean developmental period of C. keni on B. zonata and S. littoralis eggs was significantly shorter than those fed C. cephalonica eggs and both mite species. Deutonymphs of C. keni were consumed similar number of insect eggs, while during the oviposition period, more B. zonata eggs were consumed. A diet of C. rodriguez provided the shortest oviposition period and longevity, while C. cephalonica eggs showed the longest period in this respect. During the oviposition period, preying on B. zonata and C. cephalonica eggs gave the highest fecundity rates for the predatory mite compared to S. littoralis and C. rodriguez. The sex ratio of C. keni progeny was in female-biased. Bactrocera zonata eggs as a prey gave the highest rate of oviposition as shown by the maximum fertility, net reproductive rate and gross reproductive rate as well as the shortest generation time compared to other tested prey; therefore B. zonata eggs were appropriate factitious prey for oviposition and mass rearing of the predatory mite C. keni.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Omer A. Basudan
,
Perwez Alam
,
Nasir A. Siddiqui
,
Mohamed F. Alajmi
,
Adnan J. Alrehaily
,
Saleh I. Alqasoumi
,
Maged S. Abdel-Kader
,
Prawez Alam
, and
Abd El Raheim M. Donia

A simple and sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the evaluation of biomarker β-amyrin in the leaves of fve different species of genus Ficus (Ficus carica, Ficus nitida, Ficus ingens, Ficus palmata, and Ficus vasta) grown in the Kingdom of Saudi Arabia. Chromatography was performed on glass-backed silica gel 60 F254 HPTLC plates with solvents toluene–methanol (9:1, v/v) as the mobile phase. After development, the HPTLC plate was derivatized with p-anisalde-hydereagent to give well-resolved and compact spot of β-amyrin. Scanning and quantifcation were done at 550 nm. The system was found to give compact spot for β-amyrin at R F = 0.58. The linear regression analysis data for the calibration plots showed good linear relationship with r 2 = 0.998 with respect to area in the concentration range of 100–900 ng. The regression equation for β-amyrin standard was found to be Y = 5.835X + 87. The precisions (n = 6) for β-amyrin were found to be 1.64–1.77% and 1.68–1.84%, respectively, for intra-day and inter-day batches, and the recovery values were found to be 97.6–98.3%. β-Amyrin was found to be present in three species, i.e., F. carica (0.29%, w/w), F. nitida (0. 5 4% w/w), and F. p almata (0.31%, w/w), while it was absent in F. vasta and F. ingens. The statistical analysis proves that the developed method for the quantifcation of β-amyrin is reproducible; hence, it can beemployed for the determination of β-amyrin in plasma and other biological fuids as well as in fnished products avai lable in the market.

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