Anti-Diabetic Compounds in Syzygium cumini Ready to Serve Herbal Drink

Abstract

Herbal beverages with desirable sensory attributes are an ideal way to offer consumers with phytochemicals having specific health promoting functionalities. Syzygium cumini bark decoction is used in treating diabetes mellitus in Ayurvedha medicine'. Based on the findings of earlier research work of the authors in relation to antidiabetic properties of S. cumini decoction, such as antiglycation and antioxidant activities and high total phenolic content, a ready to serve (RTS) herbal drink was developed. This work describes the chemistry of the S. cumini decoction and the RTS herbal drink developed. The decoction was prepared according to the traditional method used to prepare decoctions in Ayurvedha medicine using commercial samples. Activity guided fractionation of the decoction of the S. cumini was carried out by sequential extraction of organic solvents with different polarities. Ethyl acetate and aqueous fractions were analyzed using different chromatographic methods to determine the active compounds. Phenolic compounds of the ethyl acetate extract of the decoction were determined using Thin Layer Chromatography (TLC) method and by comparing Rf values with authentic compounds. High Performance Liquid Chromatography (HPLC) analysis was performed for the identification and confirmation of the compounds in the decoction and the RTS herbal drink. Gallic acid (Rf = 1.7min.) and ellagic acid (Rf = 3.65.min) were separated by HPLC, on a C18 column using 1% acetic acid and acetonitrile (80:20 v/v). An UV-VIS library of pure compounds were created using Millennium chromatographic manager package by injecting the pure compounds to the HPLC under the above chromatographic conditions. The LC UV-VIS spectra of the two compounds were identical with the corresponding spectra of the library. Gallic acid and umbelliferone were determined as the active compounds in the decoction by TLC method and were confirmed by applying the co-chromatography with authentic compounds. Gallic acid and ellagic acid were determined through the HPLC analysis as the active ingredients in the decoction and in the RTS herbal drink and the presence of these compounds were confirmed.