Hypoglycemic activity of aqueous extract of Oscillatoria limnetica, Blennothrix ganeshii, Hydrodictyon reticulatum and Microcoleous lacustris in normal and alloxan induced diabetic mice

Cyanobacteria or blue-green algae are an ancient group of photosynthetic prokaryotes that are found in aquatic environments throughout the world. There is an increasing body of evidence that cyanobacteria produce a wide array of low molecular weight secondary metabolites with biological activity and, as such there are recognized as an excellent source of novel pharmaceuticals. The antidiabetic effect of water extracts of freshwater algae Oscillatoria limnetica, Blennothrix ganeshii and Microcoleous lacustris were studied in normal alloxan induced diabetic mice at doses of 100, 250, and 500 mg/kg. Sugar levels were measured by using the GOD-POD method. Extracts from algae produced a dose-dependent reduction in blood glucose levels. It also compared well with the effect of tolbutamide. This study shows that algae extracts have significant activity on glucose levels in rats.