Utilization of Indonesian local NPK fertilizer for biomass production of Mastigocladus HS-46 (cyanobacteria) isolated from Indonesia as potential biofuel feedstock

Cost of biofuel production from a large amount of microalgae biomass cultivation will depend on the type of growth medium used during the cultivation process. In the previous research, it has been discovered that imported commercial NPK fertilizer can be used to grow Mastigocladus HS-46. In this study, the local NPK fertilizers from Indonesia was used to grow Mastigocladus HS-46 biomass with ratio of elements N, P, and K of 12:12:17, which is close to the ratio in Bold's Basal Medium (BBM) of 1:1:2 as the basic medium for microalgae culture. Four treatment media used to grow Mastigocladus HS-46 were BBM medium as the first control, untreated sterilized water medium from Lab. Alam water at FMIPA UI as the second control and Indonesian NPK fertilizer medium for palm oil commodity with concentrations of 350 ppm and 1050 ppm in sterilized water (Lab Alam). Treatment culture was incubated in incubation cabinet at 35 °C and light intensity of 3,300 lux for 21 days of observation and eight times sampling for each medium. Observation for 21 days showed that 350 ppm NPK medium produced the highest biomass weight and growth rate value of Mastigocladus HS-46. Based on this study, Indonesian local NPK fertilizer can be utilized as alternative media for Mastigocladus HS – 46.