CHEMICAL AND BIOLOGICAL STUDIES OF VALUE-ADDED CINNAMON PRODUCTS IN THE SRI LANKAN MARKET

Cinnamon commonly known as ‘Kurundu’ in Sri Lanka has been used as a spice since antiquity. It is obtained from the inner bark of several species of the genus Cinnamomum that belongs to the family Lauraceae. Among the cinnamon species, Cinnamomum verum (syn. Cinnamomum zeylanicum Nees) is native to Sri Lanka and is also known as “Ceylon” cinnamon or “true” cinnamon. Cinnamon produced in Sri Lanka has acquired a long-standing reputation in the international market. Today, there are many value-added products of cinnamon in the local and international market. Through a market survey four value-added cinnamon products in the Sri Lankan market containing 100% cinnamon inner bark were identified and have been subjected to chemical and biological studies along with the inner bark of true cinnamon. Phytochemical screening of 80% aqueous methanol extracts of cinnamon samples was carried out according to previously published methods. All the extracts revealed the presence of alkaloids, flavonoids, proanthocyanidins, tannins, triterpenoids and saponins and the absence of steroids and cyanogenic glycosides. The total phenolic content and anti-oxidant activity of freeze-dried 80% aqueous methanol extracts of cinnamon samples were determined by Folin-Ciocalteu and DPPH radical scavenging assays respectively according to previously published methods with modifications. Of the cinnamon samples used for the study, the highest total phenolic content and anti-oxidant activity was exhibited by the freeze-dried 80% aqueous methanol extract of cinnamon stick, which was higher than that of cinnamon bark. The coumarin content of 80% aqueous methanol extracts of cinnamon samples were determined by a modified HPLC method and was found to be below the LOD. LOD was below the maximum level for coumarin in food and beverages as specified by European Commission. α-Amylase inhibition assay and in-vitro hypoglycemic effect of cinnamon samples were carried out according to previously published methods. The highest α-amylase inhibitory activity among the cinnamon samples was exhibited by the 80% aqueous methanol extract of cinnamon stick. All the cinnamon samples used for the study enhanced the glucose uptake in yeast cells suggesting that they may have an effect on controlling blood glucose levels in humans. Findings of this research maybe of potential use to give a scientific backing to the value-added cinnamon products in the local and global market.