Search Results (3)

Our attempts to obtain a new mushroom-derived immunostimulatory preparation containing organically bound selenium and zinc have focused on the interactions between selenites and zinc(II) in liquid culture media and their effects on transport into the mushroom cell. Previously, we found that, even if Zn²⁺ and SeO₃²⁻ concentrations in the liquid medium are not high enough to precipitate ZnSeO₃, the accumulation of selenium in the presence of zinc, and zinc in the presence of selenites, significantly dropped. This effect was more dependent on the molar ratio of ions in the medium than on the concentration values. We hypothesized that the formation of zinc–selenite soluble complexes with charges depending on the ion concentration ratio in the aquatic environment affects the first stage of ion transport into the fungal cell—biosorption. To verify this, we found the zinc–selenite molar ratio at which the complexes of the highest stability are formed, examined the influence of the molar ratio of ions in the medium on the concentration of Zn and Se in the mushroom cell wall, and investigated the correlation between the concentration of selenites not bound in complex compounds and the Se concentration in the cell wall. The results indicate that the molar fraction of Zn(II) in a liquid medium in the range of 0.5–0.6 promotes the formation of the most stable complexes. At the same time, it significantly reduces the percentage of free selenites in the medium and most strongly inhibits the biosorption process of both zinc and selenium. Full article

Mycelial cultures of Lentinula edodes, an edible and medicinal mushroom, have been used in our previous research to obtain selenium-containing immunomodulatory preparations. Our current attempts to obtain a new preparation containing both selenium and zinc, two micronutrients necessary for the functioning of the immune system, extended our interest in the simultaneous accumulation of these elements by mycelia growing in media enriched with selenite and zinc(II) ions. Subsequently, we have studied the effects of new L. edodes mycelium water extracts with different concentrations of selenium and zinc on the activation of T cell fraction in human peripheral blood mononuclear cells (PBMCs). Flow cytometry analysis was used to measure the expression of activation markers on human CD4+ and CD8+ T cells stimulated by anti-CD3 and anti-CD3/CD28 antibodies (Abs). It was demonstrated that statistically significant changes were observed for PD-1 and CD25 antigens on CD8+ T cells. The selenium and zinc content in the examined preparations modified the immunomodulatory activity of mycelial polysaccharides; however, the mechanisms of action of various active ingredients in the mycelial extracts seem to be different. Full article

The Se–Cl interactions in five selenite chlorides (α,β-Zn₂(SeO₃)Cl₂ (sofiite and its polymorph), α,β-Cu₅O₂(SeO₃)₂Cl₂ (georgbokiite and parageorgbokiite), and KCdCu₇O₂(SeO₃)₂Cl₉ (burnsite)) have been investigated by means of the analysis of their theoretical electron density distributions. The analysis reveals the existence in the structures of two basic types of interactions: intermediate interactions with essential covalent contribution and closed-shell interactions. In Zn₂(SeO₃)Cl₂ polymorphs and burnsite, all metal-oxide and metal-chloride interactions are of the first type, whereas in georgbokiite and parageorgbokiite, the Jahn–Teller distortion results in the elongation of some of the Cu–X bonds and their transition to the closed-shell type. All anion–anion interactions are of the closed-shell type. The energy of the closed-shell Se–Cl interactions can be estimated as 1.4–2.6 kcal^.mol⁻¹, which is comparable to weak hydrogen bonds. Despite their weakness, these interactions provide additional stabilization of structural architectures. The Se⁴⁺–Cl⁻ configurations are localized inside framework channels or cavities, which can be therefore be viewed as regions of weak and soft interactions in the structure. Full article