Along with camelina and jatropha, marine algae is a front runner in the search for a renewable feedstock for production of commercial quantities of biofuel.
While marine algae produce lipid oils, fat molecules that store energy needed for fuel production, the process occurs when they are nutritionally starved, which also stunts their growth. When well-nourished, the algae do grow well, but produce carbohydrates instead of the desired lipids for conversion to fuel.
But, in a breakthrough with potentially massive implications for production of commercial quantities of biofuel, researchers at the renowned Scripps Institution of Oceanography at the University of California, San Diego have developed a way to target a specific enzyme inside a group of microscopic algae known as diatoms, metabolically engineering a way to increase their production of lipids without hurting growth.
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The researchers targeted fat-reducing enzymes inside the diatoms and tweaked their metabolism to increase lipids without compromising growth, university officials said. Emily Trentacoste and her colleagues used a data set of genetic expression (transcriptomics) to target a specific enzyme inside the diatoms (Thalassiosira pseudonana). By metabolically engineering a lessening of the fat-reducing lipases enzymes, the researchers were able to increase lipids without compromising growth.
The potential biofuel implications are enormous, as the researchers maintain that the genetically altered strains they have developed could be produced broadly in other species.
Scripps graduate student Emily Trentacoste, who led the research efforts, commented, "These results demonstrate that targeted metabolic manipulations can be used to increase accumulation of fuel-relevant molecules… with no negative effects on growth. We have shown that engineering this pathway is a unique and practical approach for increasing lipid yields.''
The study, co-authored by Mark Hildebrand, Scripps marine biology professor, William Gerwick, Roshan Shrestha, Sarah Smith, Corine Gle, and Aaron Hartmann was reported in last week's online edition of the "Proceedings of the National Academy of Sciences.''
Hildebrand said that the accomplishment was significant, commenting, "Scientifically this is a huge achievement. Five years ago people said you would never be able to get more lipids without affecting growth negatively'. This paper shows that there isn't an intrinsic barrier and gives us hope of more new things that we can try - it opens the door to a lot more work to be done.' ' Paper coauthor William Gerwick, a distinguished professor of oceanography and pharmaceutical sciences at Scripps’s Center for Marine Biotechnology and Biomedicine and UC San Diego’s Skaggs School of Pharmacy and Pharmaceutical Sciences remarked, “It seems especially fitting that Scripps-UC San Diego is displaying so much leadership in the field of sustainable biofuels from algae, for instance with the California Center for Algae Biotechnology starting here, given the history of the institution playing such a pivotal role in climate change research. But these advances do not happen in isolation, and the current project is a great illustration of how different labs can collaborate to achieve greater advances than possible singly.”
The researchers are well aware of the economic implications of their study. By increasing the yields of algae biofuel, production costs for biofuels could be lowered, the researchers believe. The team also said the speed of algal biofuel crop production could be advanced, writing in their paper, “Maintaining high growth rates and high biomass accumulation is imperative for algal biofuel production on large economic scales.”
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The research when patented and commercially available has the potential to move algae to the forefront of the most promising feedstocks for future biofuel production. Algae’s advantages include their widespread availability, higher oil yields and that they reduce the pressure on cultivated land for production of biodiesel. Thus, algae will be the future of fuel. Algae as a fuel source are incredible. Some types of algae are made up of 50 percent oil, which can be made into biofuel more economically. Theoretically, algae can yield between 1,000-20,000 gallons of oil per acre, depending on the specific strain.
Accordingly, expect to see much more on the Scripps research in the future – given the research’s potential impact, the one thing the Scripps researchers will not lack in the future is investment cash.
By. John C.K. Daly of Oilprice.com