Vol. 56 No. 1 (257) (2022)

The structure-forming properties of mineral conditioners caused by acidic treatment have been studied by means of turbidimetry as well as particles size distribution methods. Three types of mineral conditioner having СаО, SO₄^2– and РO₄^3– groups on the surface have been investigated. The first two types were treated with nitric acid, and the third with phosphoric acid. The treatment of mineral conditioners with phosphoric acid causes a decrease in the effluent turbidity, whereas when treating СаО group containing mineral conditioner with nitric acid a sharp increase in this parameter is observed. When treating sulfo group mineral conditioner this increase is not significant.

The computer modeling of complexes of pyridinium peroxodisulfates (С_nPyr)₂S₂O₈, where n=8; 12; 15; 16; 18; 20, have been done. The structural and energetic parameters of complexes (С_nPyr)₂S₂O₈ have been calculated by molecular-dynamic at 300 K and semi-empirical quantum-chemical methods. The values of geometric and energetic parameters of optimized complexes (С_nPyr)₂S₂O₈ in vacuum and in aqueous medium, and the results of total energy quantum-chemical calculations are given. It has been established that the length of alkyl chain significantly effects on electrostatic interactions and energetically more beneficial formation of a complex with alkyl chain length n=16.

The work is devoted to a comparative study of the physicochemical, organoleptic characteristics of oils obtained by extraction method using sunflower oil and pomace remaining after their processing in order to identify the prerequisites for further use. The study object was the seeds of wine grapes of Khindoghni and Areni (grown in the Republic of Armenia), harvest of 2019–2021. The purpose of this study was to determine the comparative indicators of the quality and content of fatty acids in grape oils by gas-liquid chromatography. The optimal conditions for obtaining high quality unrefined grape oil for the food and pharmaceutical industries from grape seeds of Khindoghni and Areni varieties by the extraction method were determined: temperature 45–50℃, at atmospheric pressure and carbon dioxide gasbag (CO₂), stirring time 16 h. Under these optimal conditions the oil yield was 9.5%. It has been shown that oils from the seeds of Khindoghni and Areni grape varieties contain 1.181 mg/100 g tocopherols, 3.2 mg/100 g carotenoids, vitamins C, P, E and the pomace of their processing contains valuable free organic acids: 0.093 mg/mL oxalic, 3.105 mg/mL tartaric, 0.48 mg/mL citric. It has been shown that the content of macro- (Fe, Cu, Zn, Ca, Mg, etc.) and microelements (Mn, Co, Cd, V, Se, Cr, As, Pb, etc.) in the seeds of the studied samples are within permissible limits. On the basis of the research carried out, a scheme for the complex processing of grape raw materials has been developed.

In this study an available reversed-phase HPLC method for the identification of sibutramine with UV detection and isocratic elution mode was developed, the evaluation of the method applicability and determination of validation indicators were carried out. It has been shown that the developed method meets the current international requirements. To search for sibutramine, the developed method has been used in some biologically active additives ("Lipocarnit", "Pineapple extract", "Turboslim night" and "Turboslim day").

The textural and catalytic characteristics of the surface of silica gel modified with zinc oxide by the sol-gel method and by means of a chemical transport reaction (CTR) have been studied. It was found that catalytic activity of the obtained contacts depends on both the nature and the structural and textural characteristics of the supported ZnO. Using the example of the reaction of low-temperature oxidation of propane, it was found that lower limit of the release of radicals from the surface into the volume with the CTR modification method is lower by 15–20 degrees than in the case of the sol-gel method. It was shown that the catalyst obtained by applying the active phase on the surface of the support by the CTR method is more efficient due to the energy homogeneity of its active centers and the texture characteristics of the surface.

Structural transitions of DNA and bovine serum albumin (BSA) and their complexes with methylene blue (MB) and Hoechst 33258 (H33258) by UV-denaturation method have been studied. The obtained results revel that MB stabilizes both protein dimensional structure and DNA double-stranded structure, while H33258 stabilizes double-stranded structure of DNA and destabilizes protein structure. It was also revealed that the stabilizing effect of MB on native structure of DNA is more pronounced at relatively low ligand concentrations, than on protein.

In this work the effect of aspirin on stability of rat blood erythrocyte membranes was studied, using acidic hemolysis method. Hemolysis rate of erythrocytes was shown to depend on preservation time of rat erythrocyte suspension. With increasing of preservation time the original value of optic density of rat erythrocyte suspension decreases and hemolysis time reduces. It was also shown that in the presence of aspirin the membrane stability of low-stable erythrocytes increases, moreover, hemolysis duration enhances, while aspirin leads to decreasing of membrane stability of both high-stable and enhanced-stable erythrocytes of rats.

The article presents the first record of the genus Argiope, orb-weaver spiders from the Araneidae family in Armenia. The two female specimens of Argiope bruennichi (Scopoli, 1772) were found in the Lori Region (northern part), and two specimens of the female spider of Argiope lobata (Pallas, 1772) were recorded in the Tavush Region (north-eastern part) and Armavir Region (south-western part) of Armenia in 2020–2022.

Polyphenols constitute one of the most numerous and ubiquitous groups of fungal metabolites and are an integral part of the human diet. These molecules can be met as simple phenolic compounds or highly polymerized compounds. Recent interest in phenolic compounds has increased, owing to their antioxidant capacity. Besides, these compounds can have possible beneficial implications in human health, such as in the treatment and prevention of cancer, cardiovascular diseases, and other pathologies. Since there is little research done in Armenia, the data is scattered. This review aims to combine domestic and abroad papers on this matter.

Currently, the cosmetic industry is in a constant search for valuable bioingredients with anti-aging (antioxidant, anti-inflammatory, anti-collagenase, anti-elastase, anti-hyaluronidase and anti-tyrosinase) properties. Edible and medicinal Agaricomycetes mushrooms (macrofungi) as unlimited source of bioactive compounds and enzymes have mainly been studied for their nutritional value and medicinal properties. They have also been included in cosmetic formulations for topical and oral administration however there is slow progress in their usage as cosmeceuticals.

We described 19 medicinal, including 12 edible mushrooms belonging to 18 genera of Agaricomycetes fungi distributed in Armenia – as potential cosmeceuticals. Further evaluation of mushrooms resources in Armenia will revealed new species and promote their biotechnological exploitation not only as mushroom-derived nutraceuticals and pharmaceuticals, but also cosmeceuticals. Advances in biology and biotechnology of Agaricomycetes will further assist development of myco-cosmetology in Armenia.

Promotion and coverage of breastfeeding are considered to be the cost-effective public health measures in terms of Healthcare System. The aim of the research is to assess an influence of breastfeeding on infants’ health and quality of life (QL) parameters. This observational prospective study included 1790 newborns selected from Yerevan State Medical University’s Polyclinics (“Mouratsan”, sample=746, and “Heratsi”, sample=1044). Data collection took a period between January 2016 and December 2017. Evaluation of children’s quality of life was performed with the help of the validated and adapted QUALIN questionnaire. The data related to child’s health condition were collected from the “Child Development History” cards available at the polyclinics of the investigated area. Among 1770 one year old children 1681 were ever breastfed, 1224 (69.1%) were exclusively breastfed up to 3 months, the median duration of breastfeeding was 6–7 months, 45% were breastfed for more than 6 months, and 15% were breastfed for more than 1 year. There is a significant difference between the QL scores of the ever breastfed and the never breastfed subgroups. Duration of the breastfeeding also have an influence on QL scores. The given study’s results confirm that breastfeeding among the early aged Armenian children is of great importance in their health, influencing on quality of life and morbidity rates.

With the method of variational pulsometry by R.M.Baevsky, the influence of classical music on the integral and spectral characteristics of the activity of the regulatory mechanisms of the heart rhythm of students, observed during a one-day study load, was studied by the method of computer registration and analysis of the ECG. ECG registration and analysis were carried out on students of Yerevan State University in three experimental situations: before the first lesson (physiological norm); after the end of the 6th lesson; after listening to classical music for 20 min. Two types of response of the functional indicators of students to the study load were revealed: sympathetic and parasympathetic. It has been established that after a study load, a session of music therapy contributes to a return of the levels of all studied heart rate indicators towards the physiological norm (initial values before the class).