Ternary and Quaternary Nanocrystalline Cu-Based Sulfides as Perspective Antibacterial Materials Mechanochemically Synthesized in a Scalable Fashion.

Twelve Cu-based ternary (Cu-Me1-S, Me1 = Fe, Sn, or Sb) and quaternary (Cu-Me2-Sn-S, Me2 = Fe, Zn, or V) nanocrystalline sulfides are shown as perspective antibacterial materials here. They were prepared from elemental precursors by a one-step solvent-free mechanochemical synthesis in a 100 g batch using scalable eccentric vibratory ball milling. Most of the products have shown strong antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. For instance, stannite Cu2FeSnS4 and mohite Cu2SnS3 were the most active against E. coli, whereas kesterite Cu2ZnSnS4 and rhodostannite Cu2FeSn3S8 exhibited the highest antibacterial activity against S. aureus. In general, stannite has shown the best antibacterial properties out of all the studied samples. Five out of twelve products have been prepared using mechanochemical synthesis for the first time in a scalable fashion here. The presented synthetic approach is a promising alternative to traditional syntheses of nanomaterials suitable for biological applications and shows ternary and quaternary sulfides as potential candidates for the next-generation antibacterial agents.

In vitro study of biological activities of anthocyanin-rich berry extracts on porcine intestinal epithelial cells.

BACKGROUND: Anthocyanins, compounds that represent the major group of flavonoids in berries, are one of the most powerful natural antioxidants. The aim of this study was to evaluate biological activities and comparison of anthocyanin-rich extracts prepared from chokeberry (Aronia melanocarpa), elderberry (Sambucus nigra), bilberry (Vaccinium myrtillus) and blueberry (V. corymbosum) on the porcine intestinal epithelial IPEC-1 cell line. RESULTS: The IC50 values calculated in the antioxidant cell-based dichlorofluorescein assay (DCF assay) were 1.129 mg L(-1) for chokeberry, 1.081 mg L(-1) for elderberry, 2.561 mg L(-1) for bilberry and 2.965 mg L(-1) for blueberry, respectively. We found a significant negative correlation (P < 0.001) between cyanidin glycosides content and IC50 values. Moreover, extracts rich in cyanidin glycosides stimulated proliferation of IPEC-1 cells and did not have cytotoxic effect on cells at an equivalent in vivo concentration. CONCLUSIONS: We found that the chokeberry and elderberry extracts rich in cyanidin glycosides possess better antioxidant and anticytotoxic activities in comparison to blueberry or bilberry extracts with complex anthocyanin profiles.

Phytotoxic and Antibacterial Activity of Essential Oil of New Peppermint Cultivar.

A new menthol cultivar of Mentha x piperita L. bred in East Slovakia was evaluated for the biological activity of its essential oils (EOs). The content and composition of the EO components changed during plant development and the different effects of samples collected each month (April - September) within the growing season were noted. EOs are considered to be an important source of potential allelochemicals. Changes in EO composition influenced phytotoxic activity. Stimulation and inhibition of seed germination and root elongation occurred with different EO concentrations. The four tested bacterial strains: presented different resistance to the samples collected in different growing periods.