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DEVELOPMENT OF A SPECTROPHOTOMETRIC METHOD FOR ASSESSMENT OF THE RELATIVE REACTIVITY OF MONOCARBONYL ANALOGS OF CURCUMIN WITH 2-(DIMETHYLAMINO)ETHANETHIOL
No full textIn order to improve the bioavailability of curcumin, studies have been undertaken to prepare the so-called monocarbonyl analogs of curcumin (MACs) and assess their biological activity. These analogs contain an electrophilic α,β-unsaturated carbonyl moiety (Michael acceptor). Several key biological pro-cesses are connected/controlled with thiol alkylation (glutathione, cysteine, cysteine peptide residues). The most likely reaction is the Michael addition between the α,β-unsaturated acceptor and a correspond-ing thiol. 2,6-Bisarylidenecyclohexanone and 3,5-bisarylidenepiperidin-4-one scaffolds offer convenient tunability of electrophilicity and redox properties of the Michael acceptor by the introduction of various substituents. In this study, several MACs were prepared by Claisen-Schmidt condensation reaction, and their reactivity with 2-(dimethylamino)ethanethiol was evaluated. For this purpose, based on the UV-Vis spectra of the analogs and thiol(s), a proper method for spectrophotometric evaluation of their reactivity with 2-(dimethylamino)ethanethiol was optimized. The relative reactivity of the analogs was 7>2>5>4>1≈6. The developed method is simple, and it can be extended to assess the reactivity of other MACs.Keywords:synthesis; monocarbonyl analogs of curcumin; thiols; 2-(dimethylamino)ethanethiol; Michael additio
Project Management Life Cycle Approaches For Software Development
Full text linkThe project from its beginning to its finalization goes through different phases that together form the so-called
project life cycle. The paper analyzes four basic project management life cycle approaches that are applied especially in the
management of software projects: predictive project management life cycle approach; Iterative project management model;
Incremental project management approach and Agile project management approach. The literature review shows that,
despite the fact that agile methodologies such as Scrum are the most preferred in software development, in certain cases,
especially for projects with stable, low risk environments, etc., other approaches can be used effectively and efficiently
Effects of different irradiation doses and storage period on microbiological characteristics of wheat (Triticum aestivum L.)
No full textMicrobiological analysis of wheat (Triticum aestivum L.) treated with different doses of ionizing radiation (0.2 kGy, 0.5 kGy, 1 kGy, 5 kGy and 10 kGy) is presented in this paper. The aim was to determine the influence of different irradiation doses on the microbial population profile of wheat. In all samples, the total bacterial count and the populations of Enterobacteriaceae, Escherichia coli, Salmonella spp, coagulase-positive Staphylococci, Pseudomonas aeruginosa, Bacillus cereus, Clostridium perfringens, yeasts and molds were examined. The analyses were carried out twice: immediately after irradiation and nine months after treatment. Obtained results revealed the presence of Bacillus cereus, Enterobacteriaceae, yeasts and molds in all examined samples. Salmonella spp, Pseudomonas aeruginosa, Escherichia coli and Clostridium perfringens, were not detected. It has been found that the number of microorganisms decreases with the increase in the irradiation dose, with no viable microorganisms detected at the dose of 10 kGy. In all examined samples, nine months after irradiation, there was a noticeable reduction in the number of microorganisms. Only yeasts and molds were detected at a dose of 5 kGy, while no microbial growth was observed at 10 kGy. There are no reference studies on Enterobacteriaceae inactivation in wheat by ionizing radiation and storage. Therefore this study is the first contribution to understanding this microbial community decrease by gamma radiation after room temperature storage. The results highlighted the prolonged effect of ionizing radiation treatment on the microbiological safety of wheat