A Green Bioactive By-Product Almond Skin Functional Extract for Developing Nutraceutical Formulations with Potential Antimetabolic Activity

Molecules. 2023 Dec 3;28(23):7913. doi: 10.3390/molecules28237913.

Abstract

(1) Background: almond peels are rich in polyphenols such as catechin and epicatechin, which are important anti-free-radical agents, anti-inflammatory compounds, and capable of breaking down cholesterol plaques. This work aims to evaluate the biological and technological activity of a "green" dry aqueous extract from Sicilian almond peels, a waste product of the food industry, and to develop healthy nutraceuticals with natural ingredients. Eudraguard® Natural is a natural coating polymer chosen to develop atomized formulations that improve the technological properties of the extract. (2) Methods: the antioxidant and free radical scavenger activity of the extract was rated using different methods (DPPH assay, ABTS, ORAC, NO). The metalloproteinases of the extracts (MMP-2 and MMP-9), the enhanced inhibition of the final glycation products, and the effects of the compounds on cell viability were also tested. All pure materials and formulations were characterized using UV, HPLC, FTIR, DSC, and SEM methods. (3) Results: almond peel extract showed appreciable antioxidant and free radical activity with a stronger NO inhibition effect, strong activity on MMP-2, and good antiglycative effects. In light of this, a food supplement with added health value was formulated. Eudraguard® Natural acted as a swelling substrate by improving extract solubility and dissolution/release (4) Conclusions: almond peel extract has significant antioxidant activity and MMP/AGE inhibition effects, resulting in an optimal candidate to formulate safe microsystems with potential antimetabolic activity. Eudraguard® Natural is capable of obtaining spray-dried microsystems with an improvement in the extract's biological and technological characteristics. It also protects the dry extract from degradation and oxidation, prolonging the shelf life of the final product.

Keywords: ABTS; AGEs; DPPH; Eudraguard® Natural; MMP-2; MMP-9; MMT assay; ORAC test; almond skins; spray-drying technologies.

MeSH terms

  • Antioxidants* / chemistry
  • Antioxidants* / pharmacology
  • Dietary Supplements
  • Free Radicals / chemistry
  • Matrix Metalloproteinase 2
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Prunus dulcis*

Substances

  • Antioxidants
  • Matrix Metalloproteinase 2
  • Plant Extracts
  • Free Radicals

Grants and funding

This research received no external funding.