The present study aims to develop new antioxidant candidates prepared by hemisynthesis from piperine isolated from Piper nigrum fruits. The first derivative synthesized was piperic acid, with a yield of 2,55%, and from the latter were obtained: methyl piperate, ethyl piperate and isopropyl piperate with yields of 76,75 %, 88,93 % and 95,3 %, respectively. The isolated and synthesized molecules were characterized by infrared and mass spectrometry. Analysis of antioxidant activity by DPPH yielded IC50 values of 8,77; 2,75; 8,35; 0,30 and 0,12 mg/ml for piperine, piperic acid, methyl piperate, ethyl piperate and isopropyl piperate, respectively. These results indicate a significant improvement in antioxidant activity over the starting product, piperine.

Grapevines face the dual challenge of sustaining yield and fruit quality under arid and increasingly variable environmental conditions. This study characterized the phenotypic variability and multi-year stability of 49 grapevine (Vitis spp.) accessions conserved in the Chincha germplasm bank over three consecutive growing seasons, with the aim of identifying promising material for table grape, pisco (a traditional grape-based distille spirit from Peru), and wine production. Morphological traits (cluster weight, berry weight and dimensions), colorimetric parameters (CIELAB), and physicochemical attributes (moisture, dry matter, soluble solids, pH, titratable acidity, maturity index, and reducing sugars) were evaluated. Multivariate analyses (PCA, hierarchical clustering), genotype × environment interaction models (AMMI and GGE), stability indices (ASV and WAASBY), and assessments of inte...