Isolasi dan Karakterisasi Mikroalga Yang Berpotensi Sebagai Bahan Baku Biodiesel di Sungai Mencirim Kabupaten Deli Serdang Sumatera Utara

Abstrak

The problem of dwindling fossil energy sources has led to a decline in energy production in Indonesia, necessitating renewable energy that can be utilized for a long period. One renewable energy source that can be a solution to this problem is the production of biodiesel from the lipid content of microalgae in the mencirim river. The purpose of this study is to determine the presence of microalgae in the mencirim river that have potential to be used as biodiesel feedstock and characteristics of microalgae that have the potential to be used as biodiesel feedstock. The research activity began with the collection of river water samples from 2 sampling ponts which were than tested for pH, temperature, and dissolved oxygen in the laboratory of Medan Research Standardization and Industrial Center, the next activity involved the isolation process using the streak quadrant method, resulting in 4 microalgae: Chlorella sp., Cosmarium sp., Fragilaria sp., and Cymbella sp., originating from sample point 1. Meanwhile, sample point 2 yielded isolates: Chlorella sp. and Synedra sp. During the culturing process, the growth of the microalgae was measured using a turbidimeter. The next step is to measure the lipid biomass of microalgae using the spectrophotometric method. The results of the growth rate observation showed that the highest growth rate occurred on day 5, while the lowest growth rate was on day 15. The results of lipid biomass measurements revealed that the types of microalgae in the Mencirim River with potential as biodiesel raw materials are Chlorella sp., Cosmarium sp., Fragilaria sp., and Synedra sp. The exploration of the Mencirim River thru microalgae isolation and characterization has uncovered other potential benefits from utilizing the Mencirim River.