Desy M.H. Mantiri, Rene C. Kepel, Antonius P. Rumengan and Alfred O. Kase
Abstract
The purpose of this study is to determine the ability of antioxidant bio activity and chlorophyll concentration in green algae Halimeda opuntia, H. taenicola, and Ulva prolifera. from Totok Bay. It is located in Southeast Minahasa Regency and is a mining waste disposal area. The waters is highly turbid with a visibility of only 26 cm, and the sediment contains metals exceeding the quality standard. As a control, green algae of the same species were taken from Tongkaina waters, Manado City. The antioxidant analysis was done using DPPH method with 96 micro plate wells. For chlorophyll analysis, UV-Vis Spectro photometer was employed.The spectro photometer analysis showed that the algae from Totok Bay had an antioxidant activity, IC50 of1433.85 ug/mL for H. opuntia, 16387771.05 ug/mL for H. taenicola and 484.02 ug/mL for U. prolifera. Sample extract from Tongkaina waters had an IC50 of 666.91 ug/mL for H. opuntia, 629.79 ug/mL for H. taenicola,and 3127.79 ug/mL for U. prolifera. Mean chlorophyll-a concentration in green algae from Totok Bay waters was 2.92 ug/mL for H. opuntia, 5.38 ug/mL for H. taenicola, and 6.91 ug/mL for U. prolifera, while thesample extracted from Tongkaina waters had men chlorophyll-a concentration of 4.84 ug/mL in H. opuntiaand 5.09 ug/mL in H. taenicola.