Lemongrass (Cymbopogon citratus)-incorporated chitosan bioactive films for potential skincare applications.

Circular economy, and concerns about environmental waste, is fostering the development of sustainable alternative products in a range of industries. In the dermo-cosmetic field, the market for sustainable anti-aging skincare products has increasingly grown over the last years. The innovation of this work was to develop chitosan films incorporating lemongrass essential oil (LEO) that could potentially be applied as a green cosmetic skin treatment due to their anti-oxidant and antimicrobial properties, using renewable and biodegradable materials. Different concentrations of LEO (i.e., 0.5, 1.0, and 1.5 % w/w) were formulated into chitosan filmogenic matrices, forming skincare bioactive films. Their antioxidant properties and water vapor permeability were strongly governed by the LEO concentration. Chitosan bioactive films containing 0.5 % LEO showed cellular viability over 70 %, while those with 1.5 % LEO had similar antioxidant capacity as NAC (N-acetyl-L-cysteine), used as the positive control to inactivate intracellular reactive oxygen species (ROS) in HaCat cells not treated with H2O2. The developed bioactive films showed activity against Escherichia coli and Staphylococcus aureus. Our LEO-loaded chitosan biofilms may be used as sheet masks with antioxidant and antimicrobial properties for skincare, with high flexibility and selected permeability, and without cytotoxic risks.

Diversity of settlement-stage reef fishes captured by light-trap in a tropical south-west Atlantic Ocean coastal reef system.

This study reports the results of 5 years of monitoring reef fish post-larvae using light traps in the Bay of Tamandaré, north-east Brazil. An annotated checklist of pre-settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post-larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species-rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement-stage reef fishes in the tropical south-west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre-settlement reef fishes.