American Journal of Chemistry

Toxicity of Two Extracted Destruxin Against Palpita unionalis (Lepidoptera: Crambidae) under Laboratory and Field Conditions

2021-08-16T05:39:52-05:00

Olive trees are subjected to attack by many insect pest species that affect yield quality and quantity. Among the most common olive pest species surveyed in Egypt is Palpita unionalis. The fungus, Metarhizium anisopliae (Metschnikoff) Sorokin produces some cyclic peptide toxins, destruxins, Destruxin which may play a role in its pathogenicity in insect pests and decreases the infestations of many harmful pests. The present study aimed to evaluate the efficacy of this two solated Destruxin (Destruxin A-760 and Destruxin A- 724) against P. unionalis under laboratory and field conditions. The results obtained showed that the LC50 of Destruxin A-760 on the third larval instars was 151 ppm. However, when Destruxin A- 724 was applied on the target pest, the LC50 reached to 185 ppm. Under field conditions, both isolated Destruxin declined the rate of infestation by P. unionalis with the least infestation in case of treatment with Destruxin A- 724 compared to untreated olive trees. The yield of harvested olive fruits increased due to treatment with isolated Destruxin the highest yield in case of trees treated with Destruxin A-760.

Control of Pegomyia hyoscami (Vill) (Diptera: Anthomyidae) using Chitosan and Nano Chitosan

2021-08-16T05:43:19-05:00

Sugar beet is considered one of the most important crops in Egypt because it was used in the production of sugar as it contains 15-20% sugar Pegomyia hyoscami (Vill) ((Diptera: Anthomyidae); harmful insect pest causing a lot of damage of the sugar crop. Chitosan (CS)-g-poly (acrylic acid) (PAA) nanoparticles, which are well dispersed and stable in aqueous solution have been prepared by template polymerization of acrylic acid in chitosan solution which have an insecticidal effect on insect pests. The usage of chitosan and nano chitosan test against Pegomyia hyoscami Results showed that, the LC50 obtained 111 and 56 ppm after P. hyoscami treated with different concentrations of chitosan and nano chitosan. Also, under field conditions when P. hyoscami treated with the chitosan and nano chitosan, the number of eggs significantly 53±1.7and 9±8.3eggs/ female as compared to 272±8.7 eggs /female in the control. The percentage of egg hatching, larval mortality, malformed pupae and malformed adults significantly decreased in case of chitosan treatments and almost reduced after nano chitosan treatments. The weight of sugar beet significantly increased to 2490±66.11and 1220±45.09 kg/ feddan as compared to 1780±55.43and 1220±45.09 kg/ feddan in the control during season 2016 and 2017 respectively.

Kinetics of Phase Interaction During Secondary Cast Iron Melting

2021-08-16T05:46:39-05:00

The article deals with the kinetics of phase interaction during secondary cast iron melting in cupolas and electric furnaces. The calculation of mass transfer according to the equations of electrochemical kinetics is possible only for individual cases. As the task of secondary melting of cast iron is to achieve a certain composition of cast iron, it is advisable to program complex mass transfer processes in the form of a generalized function, including the transport coefficients and the driving force of mass transfer. It is proposed to introduce the notion of the visible mass transfer coefficient (k^v), which is the density of the mass flow of an element related to one percent of the element's concentration in cast iron. The interaction of phases in devices for secondary cast iron melting is analyzed according to the laws and periods of melting. A mathematical model of mass transfer during secondary cast iron melting has been developed. Studies were conducted using a laboratory gas cupola and a 700 kg/h gas cupola, and quantitative characteristics of mass transfer have been established.

Design and Schematic Evaluation of Dextran Conjugated Dexibuprofen, a Gastrosparing NSAID

2021-08-16T05:50:07-05:00

A novel prodrug approach was undertaken to develop the safe and therapeutically efficacious dexibuprofen to avoid oral NSAIDs induced ulceration. Dexibuprofen was esterified with dextran, using N,N-carbonyldiimidazole in one pot reaction. Synthesized dexibuprofen prodrug was characterized and evaluated by FT-IR and NMR spectroscopy, molecular weight, lipophilicity, partition coefficient, protein binding, degree of substitution, hydrolysis in simulated GI fluids, in-silico ADME properties and pharmacological potentials. Structural profile of dexibuprofen prodrug was elucidated by an ester linkage, glucosidic ring anomeric proton, dextran monomer protons and ester carbonyl carbon signals. Prodrug possessed physicochemical features as molecular weight of 83,368.11 g/mol, log P of 5.4 with optimal protein binding of 66% and degree of substitution of 25.3%. It was significantly hydrolyzed in SIF (99.53%) by following first-order kinetics with 85.9 min half-life. In-silico ADME properties of prodrug satisfied the Lipinski' rule of five and Jorgensen's rule of three without any CNS activity and cardiac toxicity, thus prodrug was suitable for oral administration. Prodrug has exhibited superior analgesic, anti-inflammatory, antipyretic activities devoid of antigenecity and ulceration in experimental animals. Data of the study were thus evinced that dexibuprofen prodrug is a safer therapeutic moiety in effective management of acute inflammation, pain and fever.