Relative Abundance of Cyanobacteria in Soil of Khasi Hills, Meghalaya and Determination of Antioxidant Potential of some Dominant Species

The relative abundance and antioxidant potential of some dominant cyanobacteria in the selected landuse type of Khasi Hills, Meghalaya were evaluated. A total of 105 species were isolated. Species of the genus belonging to Oscillatoria were with relative abundance of 41 to 75%. However, species occurring throughout the year with high relative abundance were Synechococcus aeruginosus (77-82%), followed Oscillatoria limosa (75%) and Anabaena spiroides (72%). The genus of Oscillatoria (O. curviceps and O. limosa ) were with high phenolic (77.05 and 73.15μgGAE/ml respectively) and flavonoid contents (65.10 and 47.33μgGE/ml respectively). These can also scavenge DPPH radical and superoxide anion more efficiently than the other species. Oscillatoria species which was observed with high relative abundance in this part of the region could be used as a good source of antioxidant.