Oleanolic acid and ursolic acid in commercial dried fruits

Abstract

Oleanolic acid (OA) and ursolic acid (UA) are natural triterpenoids that have preventive properties such as anti-tumor and anti-hepatitis activities. These triterpenes are known to exist in several medicinal plants and fruit skins. Dried fruits are usually eaten without removing the skin; thus, they may be good resources for oral intake of OA and UA. HPLC analysis of OA and UA contents in a variety of dried fruits showed that raisins contained higher levels of OA than the other fruits investigated, with green raisins containing the highest levels (79.0 mg/100 g). While raisins were found to contain only OA, dried cranberries, blueberries and cherries were shown to contain both OA and UA. The highest level of UA (65.9 mg/100 g) was detected in cranberries, which also exhibited relatively high OA levels (17.8 mg/100 g). Thus, raisins and dried cranberries can be used as rich sources of OA and UA.