Enhancement of Biomass Production from Spirulina sp Cultivated in POME Medium

Abstract

Indonesia is the largest producer coconut palm oil in the world. As increasing in production, the palm oil mill efluent are also produced in about 66% by FFB (Fresh Fruit Bunch). Palm oil mill effluent is usually processed by a traditional aerobic open lagoon or by anaerobic digestion. POMED (palm oil mill effluent digested) has a high nutrient content and it can be used as medium for microalgae cultivation. Spirulina sp is a kind of cyanobacteria contains high protein and a potential product for animal feed. This research purpose is to find optimum saving synthetic nutrient of Spirulina sp cultivated in POMED and to find optimum POMED concentration used for algae cultivation. Research was done in two steps. First step, Spirulina sp was cultivated in 20% POMED concentration with different saving nutrient (0%, 20%, 50%, 70%, and 90%). At second step, Spirulina sp was cultivated in different POMED concentration (10%, 20%, 30%, 40%, 50%, 60% v/v) for 16 days. At first 8 days, nutrient was added to medium. At second 8 days, the nutrient was not added to medium.. Optical density was monitored every day using spectrophotometer with wave length 680nm. At the end of cultivation, medium was filtered to obtain wet biomass (10% Total suspended solid). Spirulina sp can grow well in 20% POMED, save 50% from synthetic nutrient, and produced 5.93gr/l wet biomass for 9 days. Research was continued without adding nutrient and produced optimum biomass 9.8gr/l in 40% POMED for 13 days. Keywords: optimum biomassa, POMED, saving synthetic nutrient, Spirulina sp