Evaluation of a colorant and oil extracted from avocado waste as functional components of a liquid soap formulation

Abstract

The present research evaluated the antioxidant, antimicrobial and in vitro coloring capacity of extracts with different polarity obtained from avocado seeds (Persea americana Mill cv. Lorena). Besides, avocado oil was extracted from the residual mesocarps of P. americana Mill Hass cultivar by Soxhlet methodology, and the physicochemical properties of the extracted oil, as well as its fatty acid composition, were evaluated. Both the colorant and the avocado oil were used as supplies for a liquid soap type formulation. The antioxidant activity of the colorant extracts was determined by DPPH whereby water extracts showed the highest activity among the treatments. None of the extracts showed antimicrobial activity against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. The iodine value (177.52 cg I2 g-1) indicated that the avocado oil obtained has a high degree of unsaturation, and the Saponification index had a value of 190.74 mg KOH g-1. The colorant extracted with NaOH (L*=0.15, a*=0.05, and b*=-0.44) from the seeds was completely stable in a liquid soap matrix at pH 6.2 during one month of storage. This analysis suggests that it has high opportunities in the soap and cosmetic industry.