3.4.1 Biofuel from GM Macro algae
Hydrocarbon biofuels are produced by genetically modified seaweed which are obtained by inserting genes from high hydrocarbon producing micro algae into high growth seaweed species. Botryococcus braunii (BB) a green micro algae that produces large amounts of aliphatic hydrocarbon molecules is used as a source for genetic material. The genes that produce hydrocarbon in BB are identified, removed, cloned and subsequently inserted into high growth brown seaweeds like Kelp. The genetically modified kelp can be grown in coastal ocean waters. After the growth is complete it can be harvested and further processed .The hydrocarbons produced are then extracted and catalytically converted into useful …show more content…
Initially algae are cultivated in any type of industrial reactors. After the growth is complete algae is grinded. After this step oil is extracted from algae by press or expeller, solvent extraction with hexane or supercritical fluid extraction. The biomass produced after this step can be used as high protein feedstock for livestock, this causes value addition to the waste stream produced in the process. The further downstream processes involve separation and washing to obtain pure biodiesel.(Demirbas and Fatih Demirbas 2011)
Algae to oil process is simple alternative to produce biofuels. Naturally occurring algal species does not give economically feasible yield for microalgae oil. Thus scientists have developed genetically engineered species of microalgae to maximize the yield of oil produced. The advantages of algae oil are listed in the introduction part which clearly show that advances in algal biofuel production is the need of the …show more content…
The trial was 50 days long and attempted to grow GM algae along with the unmodified algae in outdoor tanks.
Freshwater algal strain Acutodesmus dimorphus was modified by inserting two genes by researchers. The first gene was to stain the algae with green fluorescent colour so that it is differentially visible. The second gene which was inserted was to increase the fatty acid biosynthesis in algae so that it can be further used to obtain biofuels. The main aim of the trial was to study the growth rate of genetically engineered algae when it is grown along with natural algae. It also aimed to observe the effect of GM algae species on the natural ecosystem. The algae was cultivated in tanks shown in Figure 8, water from five different water ponds was filled in the tanks.(Shawn et al. 2017) Figure 8: Testing of genetically engineered algal strains in open