Optimization of oil-in-water nanoemulsion system of Ananas comosus peels extract by D-optimal mixture design and its physicochemical properties

Abstract

Ananas comosus (A. comosus) is one of the many commercial crops in Asian countries well-known for its medicinal characteristics, and widely popular in the food industry. Nonetheless, large quantities of the antioxidant rich pineapple peels (PP) are discarded or used as animal fodder, thus the full potential of the PP for nanocosmeceutical applications remain untapped. This study assessed the use of D-optimal mixture design for optimizing droplet size and polydispersity index (PDI) of PP extract nanoemulsion (AcPEN), for four different independent variables (olive oil, grapeseed oil, Tween 80, water). The identified best formulation indicated satisfactory agreement, with the percentage prediction error (PPE) for the actual and predicted values being less than 10%. The optimized AcPEN (OPT-AcPEN) was organoleptically characterized and the Transmission Electron Micrograph corroborated the minimum droplet size and PDI of OPT-AcPEN being <200 nm and < 0.25, respectively. The OPT-AcPEN was stable under different storage conditions for up to 90 days, and the corresponding repeated centrifugation and freeze-thaw tests retaining the recommended pH of between 4 − 6 for topical skin application. Pertinently, the shear thinning and pseudoplastic behavior seen from the rheology results implied the suitability of OPT-AcPEN as a topical cosmeceutical nanoemulsion and could meet user’s requirements.