Vol. 59 No. 1-2 (266) (2025)

The effect of peat on the processes of neutralization of acid mine drainage (AMD) waters was studied using ICP-OES and Jar test methods. Untreated peat (from the Vardenis deposit, Armenia) and acid-activated peat were used. Peat activation means the elution of metals sorbed on the peat surface with mineral acid. In this case, active sorption groups (in particular, carboxyl) are released from metals, and acidic groups begin to act by the cation-exchange mechanism. The introduction of peat (untreated and acid-activated) into AMD leads to a decrease in the amount of alkali used in neutralizing AMD. With an increase in pH, schwertmannite and basaluminite are formed, which sorb copper, nickel, cobalt, zinc, etc. The sorption study was carried out in the range up to pH 6.15, since at higher pH values, against the background of more intensive precipitation of metal hydroxides, the sorption effect in terms of removing metals from water becomes less noticeable.

The World Health Organization, taking into account available scientific studies, recognized Stevia (Sweet Clover) in 2006 as a harmless, beneficial crop and allowed its widespread use in food and pharmaceutical production. This decision has served as a basis for various scientific groups to continue large-scale studies on the composition and bioactivity of stevia. Considering the nearly complete absence of studies on the stevia cultivated in Armenia, this work investigates the quantitative content of certain biologically active substances in stevia grown in Armenia. The following data were obtained: diterpene glycosides 19.69%, fructose, glucose, and sucrose. The study of the antimicrobial properties of the water extract from the raw material showed that it possesses pronounced antimicrobial activity.

The relationship between radii at nodes of a network of tubular pipelines transporting liquid under non-stationary flow conditions is considered. It is shown that Murray's law is applicable in this scenario as well. However, Murray's law does not hold for the average optimal flow rate, but for the root-mean-square flow rate.

Two modified versions of the cetyltrimethylammonium bromide (CTAB)-based method were compared with a commercial kit to develop a cost-effective and efficient protocol for high-purity DNA extraction from acidic soil in the habitat of wild bilberry Vaccinium myrtillus L. The CTAB-NB (no bead treatment) approach resulted in poor outcomes in both yield and quality (1.56 and 0.37 at absorbance ratios of 260/280 and 260/230). The addition of bead treatment in 0.1 mm PowerBead Tubes (Qiagen), coupled with extended mixing (CTAB-B), increased DNA yield by more than eight times and substantially improved DNA purity, yielding 545.76 ng DNA per g of soil with 260/280 and 260/230 absorbance ratios of 1.87 and 1.62, respectively. The commercial kit provided high-yielded (856.08 ng DNA per g of soil) and pure DNA with a 260/280 ratio of 1.95 and a 260/230 ratio of 2.10. The CTAB-B protocol is cost-efficient and provides high-purity DNA suitable for metagenomic PCR amplification.

It has been shown that under vibration conditions there is significant amidation of rat brain proteins, which is characteristic of inhibition processes. When studying the effect of Trifolium pratense L. (Red Clover) plants on the amidation of proteins under vibration conditions, it was shown that adding dry flowers of the plant to the animals' diet leads to noticeable decrease in the amidation of brain proteins. The study showed that the T. pratense plant has a stress-protector effect under vibration conditions. Based on the conducted research, it is proposed to use the plant T. pratense in the development of broad-spectrum anti-stress drugs.

The antitumor activity of cisplatin is achieved through covalent binding to DNA. To eliminate systemic toxicity and side effects, studies of cisplatin–DNA complexes are often conducted in combination with other drugs that selectively accumulate in tumor tissues without forming covalent bonds with DNA and are easily excreted from the body. In the present study, the interactions of the cationic porphyrins H2TOEtPyP4 and ZnTOEtPyP4 with platinated DNA were investigated in comparison with native DNA. Thermal melting curves show that the porphyrin ZnTOEtPyP4 stabilizes the platinized DNA double helix much better than H2TOEtPyP4. UV-CD spectra show that ZnTOEtPyP4 induces structural changes in the DNA double helix similar to the B-Z transition. This twisting of the DNA molecule occurs due to an increase in the binding ability of porphyrins to DNA. The binding constants of the studied porphyrins with platinated DNA are approximately twice as large as with native DNA. However, the small value of the exclusion parameter (n<2) shows that the ZnTOEtPyP4 porphyrin molecules at high concentrations are located in greater quantities on the surface of the platinated DNA molecule and stabilize it.