Winery by-products are a rich source of polyphenols, which have proven to have several beneficial biological properties, such as, antioxidant and antimicrobial activities. Therefore, this study aimed the extraction of polyphenols from winery by-products of two Portuguese red grape varieties, Touriga Nacional and Preto Martinho, and evaluate their phenolic profile, antioxidant properties and antimicrobial activity against antibiotic resistant bacteria. The polyphenols were extracted from the grapes' skins, seeds and stems. Extracts were analysed for total phenolic, anthocyanin and tannin contents, and the polyphenol profile was determined by High Performance Liquid Chromatography. The antioxidant activity of the extracts was determined by ABTS + and DPPH methods. Antimicrobial susceptibility assay was performed using Kirby-Bauer disc diffusion method. Preto Martinho variety presented a higher polyphenolic content than Touriga Nacional. Malvidin 3-O-glucoside was the most abundant compound found in the skins extracts in both varieties. The main phenolic compound found in the seeds and stems extracts was catechin. From the several flavonols quantified, rutin was the most abundant. For both varieties, the seeds extracts showed the highest antioxidant and antimicrobial properties, followed by the stems extracts. The extracts showed antibacterial activity against all tested strains except on gram-negative bacteria Salmonella enteritidis, Escherichia coli and Pseudomonas aeruginosa. These results show that, natural products, such as polyphenols, may represent a source for the development of novel antimicrobials to combat gram-positive resistant bacteria and possibly be used as natural food preservatives. However, they were not effective against gram-negative resistant bacteria which shows that polyphenols, alone, might not substitute antibiotics.

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Peripheral nerve injury and regeneration is a challenging scientific field with relevant clinical implications. Most peripheral nerve regeneration studies have been mainly carried out on rodents. However, it is important to note that the validity of the rodent as a model to study nerve injury and regeneration and translate these results into clinical practice has been questioned by several researchers. To overcome this problem, some investigators have used companion animals and large animal species as models for experimental peripheral nerve regeneration studies. Live sheep are often used in biomedical research because of availability, simplicity of care and housing, cost and body weight similar to humans and acceptance by society as a research animal. Despite these advantages, studies on nerve regeneration and repair in sheep have only been undertaken a few decades ago and compared to rat and mice experimental studies, there are much fewer investigations. The authors have compiled and sorted the available literature on experimental ovine nerve studies in order to guide the peripheral nerve investigator in choosing clinically relevant and interpretable models for studies on neural regeneration that are much needed in order to make progress towards new surgical and medical treatment of peripheral nerves.