The complexation of biogenic molecules with metals is the widespread strategy in screening for new pharmaceuticals with improved therapeutic and physicochemical properties. This paper demonstrates the possibility of using simple QSAR modeling based on topological descriptors for chelates study. The presence of a relationship between the structure (J) and lipophilic properties (logP) of zinc complexes with amino acids, where two molecules coordinate the central atom through carboxyl oxygen and amino group nitrogen, and thus form a double ring structure, was predicted. Using a cellular biosensor model for Gly, Ala, Met, Val, Phe and their complexes Zn(AA)2, we experimentally confirmed the existence of a direct relationship between logP and biological activity (Ea). The results obtained using topological analysis, Spirotox method and microbiological testing allowed us to assume and prove that the chelate complex of zinc with methionine has the highest activity of inhibiting bacterial biofilms, while in aqueous solutions it does not reveal direct antibacterial effect.

This paper proposes some results concerning the interaction of living matter of different organization levels (prokaryotes and eukaryotes) with the flux of thermal neutrons. The phenomenon of the virtual neutron trap was tested during the passage of thermalized neutrons from the Pu-Be couple through a flat layer of E. coli suspension. We have studied the metabolic characteristics of A. salina cysts before and after artificial neutron flux exposure. It has been demonstrated that the concentrations of some metals in samples of alive and dead cysts irradiated with an artificial flow of thermal neutrons are not equal. The content of Mn in alive A. salina samples has increased more than ten-fold after their interaction with neutron flux, while the amount of As decreased by a factor of two after exposure. Levels of other elements (Al, Cr, Ni, Cu, Cd, and Pb) did not show any significant difference. Trace element composition of cysts was assessed using the method of atomic absorption spectroscopy with electrothermal atomization and the Zeeman background correction.

Objective: To investigate kinetic changes in the spectral characteristics by Fourier Transform Infrared spectroscopy (FTIR) of water-lactose complexes (SMC), derived during the manufacturing process of the drug, containing release-active forms of antibodies. Methods: lactose monohydrate substance, saturated with release-active forms of affinity-purified polyclonal rabbit antibodies to recombinant human interferon-gamma (RA forms of Abs); tablets produced from this substance by direct compression after the addition of excipients (microcrystalline cellulose, magnesium stearate). Powdered and tableted placebo samples saturated with technologically processed water or phosphate-buffered saline, as well as with intact ethanol were used as control. Kinetic changes in SMC were studied using an Agilent Cary 630 FTIR spectrophotometer with a diamond ATR accessory (Agilent Technologies, USA). We used the method of X-ray fluorescence spectroscopy (EDX-7000 Shimadzu energy dispersive X-ray fluorescence spectrometer) to track changes in the fluorescence signal at certain wavelengths. The range of measured elements–11Na-92U. Results: Control of some technological characteristics of the obtained active substance (moisture, flowability) and dosage form (mean mass, disintegration rate) was used as indirect indicators of quality, but they did not allow reliably distinguishing intact lactose from the saturated one. Long-period oscillations on FTIR spectra were characteristic for all types of samples; oscillations occur at approximately two-week intervals; S/N indices were more stable for samples of RA forms of Abs than for placebo samples. On some days, the substance saturated with RA forms of Abs significantly differed from the intact lactose powder. The kinetics of the X-ray fluorescence intensity at certain wavelengths indicates the possibility of a periodic cooperative trigger transition of the system. Reversible conformational transitions are observed for powders on the 30th and 130th days (Kα 3.313 keV). For tablets at Kα 3.313 keV and Kα 1.740 keV small changes were visualized on those days (100–110th day) when hysteresis phenomena were recorded in the IR spectra of these samples. Conclusion: As a result, the evidence for a long-period dramatic conformational mobility of the water-lactose complex was obtained. Based on the data on the semiannual kinetics of IR spectra, a universal criterion for the identity of lactose powder saturated with RA forms of Abs was obtained. Also, it was confirmed that the lactose conformation state was changed by saturation with RA forms of Abs.

Background and Aim: Resistance to antifungal agents is a serious public health concern that has not been investigated enough because most studies on antimicrobials are dedicated to antibacterial resistance. This study aimed to synthesize silver nanoparticles (AgNPs) using Aloe vera extract, and to assess its antifungal activity against Candida albicans. Materials and Methods: Silver nanoparticles were synthesized by reducing Ag nitrate with aqueous A. vera extracts. Physicochemical properties of synthesized AgNPs were determined by ultraviolet–visible spectrophotometry, photon cross-correlation spectroscopy, energy-dispersive X-ray fluorescence spectrometry, X-ray diffraction analysis, and Fourier-transform infrared spectroscopy. An antifungal investigation was performed against four clinical C. albicans (C1, C2, C3, and C4) and a reference strain, C. albicans ATCC 10321. Results: Cubic AgNPs with a mean X50 hydrodynamic diameter of 80.31 ± 10.03 nm were successfully synthesized. These AgNPs exhibited maximum absorbance at 429.83 nm, and X-ray fluorescence (XRF) confirmed the presence of Ag in AgNPs solution by a characteristic peak in the spectrum at the Ag Kα line of 22.105 keV. Infrared spectra for AgNPs and A. vera extract indicated that the compounds present in the extract play an essential role in the coating/capping of synthesized AgNPs. Different concentrations (200, 100, 50, 25, 10, and 5 μg/mL) of AgNPs were tested. The antifungal activity was shown to be dose-dependent with inhibition zones ranging from 10 mm to 22 mm against C. albicans ATCC 10231, 0 mm to 15 mm against C1, 0 mm to 16 mm against C2 and C3, and 0 mm to 14 mm for C4. Minimum inhibitory concentration ranged from 16 μg/mL to 32 μg/mL against clinical C. albicans (C1, C2, C3, and C4) and was 4 μg/mL against C. albicans ATCC 10231. Conclusion: This study showed the ability of A. vera to serve as an efficient reducing agent for the biogenic synthesis of AgNPs with excellent antifungal activity.

Experimental studies have shown that with an increased level of mineral nutrition (N120P180K240) all varieties increased the yield (by 1.7–4.1 tons/ha, or by 10–25%), while the most productive varieties being Bryansky Nadezhny, Bryanskaya Novinka, Slava Bryanshchiny (21.9–22.9 tons/ha). In terms of dry substances content almost all varieties met the requirements of processing, which called for for a dry substance level in tubers of at least 20–24%. With an increase in the dose of fertilizers the amount of starch and dry matter in tubers decreased. On an average background, the starch content compared to the control decreased by 0.7–1.1%, dry substances — by 0.7– 1.2%, on an increased background respectively — by 1.2–1.7%, dry substances — by 1.4–2.7%. The taste of potatoes on an increased background of fertilizers worsened regardless of variety. In terms of darkening of the flesh, raw cleaned tubers of all varieties are not suitable for long-term storage (for example, for 24 hours), while boiled tubers of all varieties did not reduce the quality. Growing potatoes on an increased background of mineral nutrition increased the darkening of raw tubers of the studied varieties compared to control. In the studied varieties the content of reducing sugars in many cases exceeded the amount allowed for the manufacture of crispy potatoes, and therefore its quality was reduced, mainly due to the color of the slices. Almost all varieties gave puree of good quality. An increase in the background of fertilizers slightly worsened the consistency of puree, which reduced the overall estimate.