Potensi Mikroorganisme Resisten dari Pantai Timur Surabaya Sebagai Biosorben Seng

Abstract

East coast of Surabaya is one of region in Indonesia which contaminated by heavy metals, such as zinc. Zinc is one of essential heavy metals for organisms but be dangerous for human if comsumed in high concentration. So, it is important to to solve the problem to reduce the concentration of zinc in east coast of Surabaya through bioremediation using microorganism. Zinc resistant microorganism could be isolated from zinc contaminated region and be used for bioremediation agent because some microorganism developed resistance mechanism to zinc by bioaccumulation or biosorption. The aims of this study are to isolate and characterize zinc resistant microorganism from east coast of Surabaya. The most resistant microorganism will be observed for the growth in medium supplemented with zinc and without zinc. The potency of the chosen isolate to biosorb of zinc was also analyzed. Water sample from east coast of Surabaya was serries dilluted and innoculated on Luria Bertani Agar medium using  spread plated method. Microbial resistance to zinc was analyzed by grown the cell on medium containing various concentration of zinc to determine Minimum Inhibitory Concentration  (MIC) value of each microbial isolate. Cell turbidity will be observed in the chosen isolate using spectrophotometer in wave length of 600 nm to get the growth curve. The potency of the chosen isolate to biosorb of zinc was analyzed using atomic absorption spectrophotometer. From this study, six bacteria and three yeast have been isolated from east coast of Surabaya, designated as  PmbZn1, PmbZn2, PmbZn3, PmbZn4, PmbZn5, PmbZn6, PmbZn7, PmbZn8, dan PmbZn9. All isolates could grow on medium containing 8 mM ZnSO4. The most resistant bacterial was isolate PmbZn5 with the MIC of 9 mM ZnSO4. The potency of the isolate to biosorb of zinc was  94,79 and 93,57% in medium containing 4 mM and 7 mM ZnSO4, respectively.Key words: Bacteria, biosorb, resistant, yeast, zinc.