Physical, Chemical and Biological Characteristics of Sri Lankan Bee Honey Varieties

Abstract

Objectives: Honey has abundant medicinal properties. It is formed by floral nectar, swaps of plants, and the secretions of bees. The current study determined the physical, chemical, and biological characteristics of Sri Lankan raw bee honey varieties. Methods: A honey stock/library was created using local honey produced by Apis cerana, and Apis dorsata. Colour, conductivity, cell constant and pH were determined under physical tests while free acidity, water content and hydroxymethylfurfural content were determined under chemical tests. Evaluation of biological activities includes checking for antimicrobial activity, antioxidant activity and enzymatic activity. Results: The pH values recorded for A. dorsata and A. cerana honey ranged from 4.14–5.55 and 4.54–6.33, respectively. The electrical conductivity of all the samples ranged from 0.39-2.59 mS cm-1. The free acidity of honey samples of A. dorsata was between 25-81.7 meq/kg and that for A. cerana was between 40- 82.7 meq/kg. The hydroxymethylfurfural content of honey samples of A. dorsata and A. cerana were 9.38-49.50 mg/kg and 7.49-53.94 mg/kg, respectively. The two honey varieties were similar in chemical and physical characteristics tested except for water content where the water content of honey from A. dorsata was significantly higher than that of A. cerana. All honey samples investigated had antibacterial activity against gram-negative bacteria E. coli and gram-positive bacteria S. aureus. A. cerana honey had higher antioxidant activity than A. dorsata honey while A. dorsata honey had higher enzymatic activity than A. cerana honey. Conclusions: The present study reveals that the physiochemical properties of two honey varieties were similar except for water content while biological properties were significantly different. This study indicates that honey from both A. dorsata and A. cerana of Sri Lanka has potential therapeutic activities that can be used to develop natural drug formulations.