Analysis of royal jelly by spectrophotometric and capillary electrophoretic methods

Abstract

Royal jelly is one of the most attractive bee products, due to its broad composition and wide range of biological activity [1]. It has been used since ancient times for care and human health and it is still very important in traditional and folk-medicine, especially in Asia [2]. Royal jelly is produced by hypopharyngeal and mandibular glands of worker honeybees [1]. It is composed of bioactive substances such as free amino acids, proteins, sugars, fatty acids, minerals, vitamins and phenolic compounds. It also contains physiologically active substances such as 10-hydroxy-2-decenoic acid (10-HDA) [3]. Royal jelly has been demonstrated to possess a number of pharmacological and biological activities [1]. It is noteworthy that 10-HDA is considered as one of the most important components from which the royal jelly biological activity derives. Considering the antioxidant activity, very important ingredients of the royal jelly are flavonoids and phenolic compounds [4]. This study aims to evaluate the antioxidant activity of royal jelly by spectrophotometric methods and to determine 10-HDA by capillary electrophoresis. Five Lithuanian and one German sample of royal jelly were investigated in this study. Lithuanian royal jelly samples were collected in different time in June-August. Pure royal jelly was dissolved in distilled water; different dilutions were used in different analyzes. Total phenolic compounds content, total flavonoid content and antiradical (DPPH) activity of the samples was evaluated by spectrophotometric methods. 10-HDA was determined by capillary electrophoresis, using previously developed capillary electrophoresis system [5]. The separation of compounds was carried out using 300 mM, pH 9.0 TRIS borate buffer.[...]