Production of Spirulina platensis using Cheap Local Resources in Palestine
Imad Walid Abed Alrahman Aljabali
عماد وليد عبد الرحمن الجبالي
In this study five main experiments were used with different treatments to evaluate the possibility of the cheap aquaculture water such as Tilapia effluents to be used for Spirulinaproduction, and to test if solutions made by plant ash be used for Spirulinaproduction, also if brackish water and mining water have a good impact on Spirulina production, and to create a medium composed of cheap chemicals and fertilizers to be used for Spirulina cultivation, and to test if a mix made from local components be useful to produce Spirulina or not. All experiments were monitored through growth and dry weight measurements including chemical and physical characteristics for the samples with a comparison with Zarrouk medium as a reference used for each experiment alone while all experiments were done for a period of 21 days to find the best media type that stay longer for commercial purposes. In all experiments, pH values were between 8 and 11, and EC was between 9.8-30 mS/cm, while temperature was at 30 ᵒC and 35 ᵒC, and light was at 1500 and 5000 Lux for 16h light and 8h dark. The first experiment was done to evaluate the possibility of using wastewater from Tilapia-fish ponds in ADS to cultivate Spirulina. In this experiment, both treatments began with low concentrations, and the initial absorbance around 0.5 at 880nm. ZM tripled after 8 days while FW doubled in the same period and both treatments stayed at the same level till the end of the experiment. This experiment showed that Spirulina can grow in FW in a similar way like ZM with a price of 0.0015 ILS/L for FW compared to 8.9625 ILS/L for ZM. The second experiment was done through running treatments of fish wastewater, diluted brackish water, plant ash solution, and a mix of them. In this experiment, all treatments began with low concentrations as in experiment one with absorbance around 0.6 at 880nm and most of it tripled after 14 days, and ZM was the lowest one among all; so, from this experiment FW, diluted BW, PAS 3% or a mix of it could be used to cultivate Spirulina with a very cheap price compared to ZM. The third experiment was conducted to evaluate the same components as in experiment two with some modification and addition of new treatments such as mining water and creating new chemical mediums as IMJ and IMJ-1. In this experiment, all treatments began with high concentration with absorbance range between 1.6-1.9 at 880nm for all types. ZM and IMJ were the best types among all other treatments. FW stayed at the same level for the first week and began to grow with fluctuation curve till the end of the experiment. IMJ with a price of 3.66 ILS/L is lower than ZM and could be a good alternative source. The fourth experiment was run at the same time of experiment five. It was a comparison between ZM and IMJ-2. In this experiment, both treatments began with a moderate concentration with absorbance reading of 1.25 at 880nm. ZM doubled nearly after 14 days while IMJ-2 raised by 1.76 times at the same period. IMJ-2 was better than ZM till day 10 and a clear difference shown after that. IMJ-2 with a price of 1.38 ILS/L is lower than ZM and could be a very good cheap alternative source. The fifth experiment was a comparison between ZM, FW, and the following types FW:BW (9:1), FW:MW (9:1), FW:PAS-3% (9:1), FW:IMJ-1 (9:1), and a mix composed of FW:(BW+MW+PAS-3%+IMJ-1) (9:1). In this experiment, all treatments began with moderate concentrations with absorbance around 1.25 at 880nm. ZM and Mix were the best types, while ZM, Mix, and FW:IMJ-1 took a similar behavior until day 10. According to the results of the dry weight we found that it was not representative for the growth of Spirulina, and the reason is still unclear. All treatments that used in this study had lower cost than Zarrouk medium and with some optimization its’ quality could be better. The main result that was obtained from all the experiments in this study is the ability of Spirulina to grow within a wide range of chemical parameters with a cheaper price. Therefore, this study recommends the use of water from fish farming in the production of spirulina after its examination.