The transformation of penicillin G into nano/micro-sized spheres (nanopenicillin) using sonochemical technology was explored as a novel tool for the eradication of Gram-negative bacteria and their biofilms. Known by its effectiveness only against Gram-positive microorganisms, the penicillin G spherization boosted the inhibition of the Gram-negative Pseudomonas aeruginosa 10-fold (from 0.3 to 3.0 log-reduction) and additionally induced 1.2 log-reduction of Escherichia coli growth. The efficient penetration of the spheres within a Langmuir monolayer sustained the theory that nanopenicillin is able to cross the membrane and reach the periplasmic space in Gram-negative bacteria where they inhibit the β-lactam targets: the transferases that build the bacteria cell wall. Moreover, it considerably suppressed the growth of both bacterial biofilms on a medically relevant polystyrene surface, leaving majority of the adhered cells dead compared to the treatment with the non-processed penicillin G. Importantly, nanopenicillin was found innocuous towards human fibroblasts at the antibacterial-effective concentrations.

No abstract

Abstract:OBJECTIVE: Despite the great number of substances produced by the skin care industry, very few of them seem to truly have an effect on the skin. Therefore, given the social implications surrounding physical appearance, the search for new bioactive compounds to prevent or attenuate skin aging and enhance self-image is a priority of current research. In this context, being rich in valuable compounds such as proteins, phenolics, lipids and vitamins, this study is focused in the potential activity of rapeseed press cake hydrolyzates to be used as raw materials for skin care applications. METHODS:In this study, the protein-rich press residue from the rapeseed oil industry was converted enzymatically into short-chain biologically active peptides using four protease products with varying substrate specificity -Alcalase 2.4L FG, Protex 6L, Protamex and Corolase 7089. The antioxidant, anti-wrinkle and anti-inflammatory activity of the obtained hydrolyzates were evaluated in vitro while their biocompatibility with human skin firoblasts was tested. RESULTS:All hydrolyzates were biocompatible with skin fibroblasts after 24 h of exposure, while the non-hydrolyzed extract induced cell toxicity. Alcalase 2,4L FG and Protex 6L -obtained hydrolyzates were the most promising extracts showing improved bioactivities suitable for skin anti-ageing formulations, namely anti-oxidant activity, inhibiting approximately 80% cellular reactive oxidative species, anti-inflammatory and anti-wrinkle properties, inhibiting around 36% of myeloperoxidase activity and over 83% of elastase activity. CONCLUSION:The enzymatic technology applied to the rapeseed oil industry co-stream results in the release of bioactive compounds suitable for skin care applications.

No abstract