Антибактериальная активность полифенолов, полученных механохимическим путем из природного сырья

This study focuses on bactericidal activity of a number of biomass-derived polyphenols (humic substances and melanins) obtained by mechanochemical activation of the brown coal and husk of buckwheat mixed with a solid oxidizing or reducing agents against opportunistic pathogens relevant to the poultry industry: Salmonella typhimurium, Shigella sonnei, Escherichia coli, Pasteurella multocida, Yersinia pseudotuberculosis, Streptococcus pyogenes, Staphylococcus aureus, and Staphylococcus epidermidis. The studied polyphenols are active against bacteria belonging to the family Enterobacteriaceae (Salmonella typhimurium, Shigella sonnei, Escherichia coli, and Yersinia pseudotuberculosis) after being subjected to mechanochemical activation in the presence of sodium percarbonate. Almost all the studied samples, except for those exposed to treatment with zinc, were active against bacteria Pasteurella multocida (the family Pasteurellacеae) and Staphylococcus epidermidis (the family Staphylococcаcеae). The samples active against bacteria Streptococcus pyogenes (the family Streptococcacеae) and Staphylococcus aureus (the family Staphylococcacеae) can be obtained by mechanochemical interaction with sodium percarbonate under certain conditionsПроведено исследование бактерицидного действия ряда полифенолов (гуминовых веществ и меланинов) из природного сырья, полученных в результате механохимической обработки смесей сырья с твердым окислителем – перкарбонатом натрия и восстановителем – цинком в отношении условно-патогенных бактерий, важных для птицеводства: Salmonella typhimurium, Shigella sonnei, Esherichia coli, Pasteurella multocida, Yersinia pseudotuberculosis, Streptococcus pyogenes, Staphylococcus aureus, Staphylococcus epidermidis. Исследованные гуминовые полифенолы проявляют активность в отношении бактерий семейства Enterobacteriaceae (Salmonella typhimurium, Shigella sonnei, Esherichia coli, Yersinia pseudotuberculosis) после механохимического взаимодействия с перкарбонатом натрия. Образцы после взаимодействия с цинком активности не проявляют. В отношении бактерий Pasteurella multocida (семейство Pasteurellacеae) Staphylococcus epidermidis (семейство Staphylococcаcеae) активны практически все исследованные гуминовые и меланиновые препараты за исключением препаратов после взаимодействия с цинком. Активные в отношении бактерий Streptococcus pyogenes (семейство Streptococcacеae), Staphylococcus aureus (семейство Staphylococcacеae) могут быть получены механохимическим взаимодействием с перкарбонатом натрия в определенных условия

Mechanochemical solid acid/base reactions for obtaining biologically active preparations and extracting plant materials

Mechanochemically assisted extraction involves the mechanical treatment of powder mixtures of plant materials and convenient reagents in special mill-activators to solubilize the biologically active substances. The reactions of the solid hydroxides, carbonates, and hydrocarbonates of alkali metals are the subject of this paper. During mechanochemical treatment, insoluble biologically active substances are transformed into water-soluble or highly reactive mechanocomposites. The types of reagents used depend on the chemical nature of the biologically active substance and the possible chemical reactions between the substance and reagents. Solid-state mechanochemical reactions between active acids and solid bases and between biogenic amines and acids and the formation of soluble complexes of biologically active substances with water-soluble and insoluble polymers were explored in this study. The advantages of using these reactions in mechanochemically assisted extraction are presented in this review

Tailoring the properties of a zero-valent iron-based composite by mechanochemistry for nitrophenols degradation in wastewaters

<p>Zero-valent iron (ZVI) is a valuable material for environmental remediation, because of its safeness, large availability, and inexpensiveness. Moreover, its reactivity can be improved by addition of (nano-) particles of other elements such as noble metals. However, common preparation methods for this kind of iron-based composites involve wet precipitation of noble metal salt precursors, so they are often expensive and not green. Mechanochemical procedures can provide a solvent-free alternative, even at a large scale. The present study demonstrates that it is possible to tailor functional properties of ZVI-based materials, utilizing high-energy ball milling. All main preparation parameters are investigated and discussed. Specifically, a copper-carbon-iron ternary composite was prepared for fast degradation of 4-nitrophenol (utilized as model pollutant) to 4-aminophenol and other phenolic compounds. Copper and carbon are purposely chosen to insert specific properties to the composite: Copper acts as efficient nano-cathode that enhances electron transfer from iron to 4-nitrophenol, while carbon protects the iron surface from fast oxidation in open air. In this way, the reactive material can rapidly reduce high concentration of nitrophenols in water, it does not require acid washing to be activated, and can be stored in open air for one week without any significant activity loss.</p