Antimicrobial resistance is a major public health concern worldwide. Albeit to a lesser extent than bacteria, fungi are also becoming increasingly resistant to antifungal drugs. Moreover, due to the small number of antifungal classes, therapy options are limited, complicating the clinical management of mycoses. In this view, antimicrobial peptides (AMPs) are a potential alternative to conventional drugs. Among these, Proline-rich antimicrobial peptides (PrAMPs), almost exclusively of animal origins, are of particular interest due to their peculiar mode of action. In this study, a search for new arginine- and proline-rich peptides from plants has been carried out with a bioinformatic approach by sequence alignment and antimicrobial prediction tools. Two peptide candidates were tested against planktonic cells and biofilms of Candida albicans and Candida glabrata strains, including resistant isolates. These peptides showed similar potent activity, with half-maximal effective concentration values in the micromolar range. In addition, some structural and functional features, revealing peculiar mechanistic behaviors, were investigated.

Essential oils have been widely used for their antimicrobial and antifungal properties, but their instability to light and high volatility limit their clinical use. Useful strategies to improve their biopharmaceutical properties are vesicular drug delivery systems, particularly liposomes. The aim of the present study was to extract, characterize, and formulate the essential oil of Artemisia annua L. in liposomes. The optimized vesicles were evaluated for their performance against different drug-resistant Candida strains. Main constituents of AEO were camphor (22.6%), artemisia ketone (17.3%) and 1,8-cineole (15.8%). Optimized nanoliposomes were loaded with 10 mg/ml of AEO. Size was 250 nm, ?-potential was -10mV, and polydispersity index was 0.21. Encapsulation efficiency was about 75%, recovery % was more than 90%. The drug release study showed that after 14 h almost 100% of AEO was released from the vesicles. Minimum fungicidal concentration (MFC) values ranged from 10 to 42 mg/ml for pure AEO. MFC of AEO-loaded in nanoliposomes ranged from 5 to 10 mg/ml. The most susceptible species to AEO loaded in nanoliposome was C. norvegensis (5.00 mg/ml), followed by C. krusei. These findings suggest that AEO could be an interesting by-product of A. annua, and the proper entrapment of AEO into nanoliposomes could optimize the biological properties and defeat fungal infections.