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BackgroundIncrease in vancomycin (Van)-resistant bacterial strains including vancomycin-resistant Staphylococcus aureus (VRSA) and lack of new effective antibiotics have become a formidable health problem.Materials and methodsWe designed a new conjugate composed of Van and a peptide Hecate (Hec; Van/Hec), and its potential antimicrobial activity was evaluated.ResultsResults from disk diffusion test, time-kill assay, determination of minimum inhibitory concentration (MIC), microscopy, and comet assay showed strong antimicrobial effects of Van/Hec against wild-type, methicillin-resistant Staphylococcus aureus (MRSA) and VRSA. Microscopy revealed that the exposure to Van/Hec results in disruption of bacterial cell integrity in all tested strains, which was not observed in case of Van or Hec alone.ConclusionOverall, we showed that the preparation of conjugates from antibiotics and biologically active peptides could help us to overcome the limitation of the use of antibiotic in the treatment of infections caused by multidrug-resistant bacteria.

Histamine is a heterocyclic amine formed by decarboxylation of the amino acid L-histidine. It is involved in the local regulation of physiological processes but also can occur exogenously in the food supply. Histamine is toxic at high intakes; therefore, determination of the histamine level in food is an important aspect of food safety. This article will review the current understanding of physiological functions of endogenous and ingested histamine with a particular focus placed on existing and emerging technologies for histamine quantification in food. Methods reported in this article are sequentially arranged and provide a brief overview of analytical methods reported, including those based on nanotechnologies.