Antibacterial Metabolites Produced by Limonium lopadusanum, an Endemic Plant of Lampedusa Island.

Lampedusa, the largest island of the Pelagie archipelago, Sicily, Italy, has proven to be a rich source of plants and shrubs used in folk medicine. These plants, often native to the island, have been very poorly investigated for their phytochemical composition and biological potential to be translated into pharmacological applications. To start achieving this purpose, a specimen of Limonium lopadusanum, a plant native to Lampedusa, was investigated for the first time. This manuscript reports the results of a preliminary biological assay, focused on antimicrobial activity, carried out using the plant organic extracts, and the isolation and chemical and biological characterization of the secondary metabolites obtained. Thus 3-hydroxy-4-methoxybenzoic acid methyl ester (syn: methyl isovanillate, (1), methyl syringate (2), pinoresinol (3), erythrinassinate C (4) and tyrosol palmitate (5) were isolated. Their antimicrobial activity was tested on several strains and compound 4 showed promising antibacterial activity against Enterococcus faecalis. Thus, this metabolite has antibiotic potential against the drug-resistant opportunistic pathogen E. faecalis.

Unveiling the mechanism of action of acylated temporin L analogues against multidrug-resistant Candida albicans.

The increasing resistance of fungi to conventional antifungal drugs has prompted worldwide the search for new compounds. In this work, we investigated the antifungal properties of acylated Temporin L derivatives, Pent-1B and Dec-1B, against Candida albicans, including the multidrug-resistant strains. Acylated peptides resulted to be active both on reference and clinical strains with MIC values ranging from 6.5 to 26 µM, and they did not show cytotoxicity on human keratinocytes. In addition, we also observed a synergistic or additive effect with voriconazole for peptides Dec-1B and Pent-1B through the checkerboard assay on voriconazole-resistant Candida strains. Moreover, fluorescence-based assays, NMR spectroscopy, and confocal microscopy elucidated a potential membrane-active mechanism, consisting of an initial electrostatic interaction of acylated peptides with fungal membrane, followed by aggregation and insertion into the lipid bilayer and causing membrane perturbation probably through a carpeting effect.

Extended-Spectrum Beta-Lactamase-Producing and Carbapenem-Resistant Enterobacterales in Companion and Animal-Assisted Interventions Dogs.

Animal-assisted interventions (AAIs) are being implemented in many countries for the beneficial effects they have on humans. Patients involved in AAI are often individuals at greater risk of acquiring infections, and these activities involve close contact between humans and animals, as is the case with humans living with a pet. The spread of multidrug-resistant Enterobacterales is a serious problem for human health; an integrated One Health strategy is imperative to combat this threat. Companion dogs can be a reservoir of multidrug-resistant pathogens, and animal-to-human transmission could occur during AAI sessions. The aim of this review was to collect the available data on the carriage of extended-spectrum beta-lactamase-producing and carbapenem-resistant Enterobacterales in companion dogs and in an AAI context. Several papers have generally addressed the issue of microbial transmission during AAIs. Studies on the intestinal carriage of extended-spectrum beta-lactamase and/or carbapenem-resistant Enterobacterales have mainly been conducted in companion animals while few data are available on the carriage in dogs participating in AAI sessions. This review aims to draw attention to the antibiotic resistance problem in a One Health context and to the importance of extending infection control measures to this human-animal interface, to keep the balance of benefits/risks for AAIs shifted towards the benefits of these activities.