Changes in secondary phenolic metabolites during storage as an aqueous suspension in comparison with the content in harvested Aloe arborescens leaves

Abstract

Aloe arborescens is a very important plant used in the cosmetics and pharmaceutical industries. The main problem using this plant for medicinal and cosmetic purposes is the rapid destruction of the active compounds in aquatic solutions. By frequently pruning the leaves, the content of three secondary phenolic metabolites (SPhMs), barbaloin, aloeresin and aloenin, in the leaves can be increased dramatically. The changes in these SPhMs were studied in an aqueous suspension of leaf exudate powder and in harvested leaves after storage for 1-45 days at 4°C in darkness. During storage in water there was rapid degradation of aloenin, but a gradual and slow degradation of barbaloin and aloeresin. In contrast, in stored leaves, the change in the relative amounts of the three SPhMs was similar, but the percentage of aloenin was higher even after 3.5 months. When these SPhMs are stored as dry powder they may last for some years. © 2006 Institute of Food Science and Technology Trust Fund.