Australian researchers find wild-type sorghum that can yield more than 10K liters ethanol per hectare
Scientists from the ARC Centre of Excellence in Plant Cell Walls at the University of Adelaide have discovered that a variety of sorghum growing wild in Australia—Arun—theoretically has the potential to yield some 10,344 liters of bioethanol per hectare (1,106 gallons US per acre) from stem tissues alone.
In an open-access study published in the journal PLOS ONE, the researchers assessed the stems of 12 varieties of sorghum for sugar content and ease of conversion to bioethanol. These included cultivated varieties and wild relatives, including Arun, which yielded significantly more bioethanol than other varieties.
Two key advantages of using stem (rather than leaves or grain) to make biofuel is that we can produce this material in low input systems; and as we do not eat this part of the plant we avoid the food versus fuel debate.—Dr. Caitlin Byrt
Despite Arun stem containing high levels of a component thought to inhibit bioethanol production, this appears to be negated by a high level of an easily fermentable sugar.
The researchers say that a large pool of untapped diversity exists in other species and subspecies of sorghum which opens new avenues of research to generate sorghum lines optimized for biofuel production.
Arcadia Biosciences—a Davis, California-based agricultural technology company—is a partner in the Centre’s research and is working with the Centre to commercialise these findings.
Caitlin S. Byrt, Natalie S. Betts, Hwei-Ting Tan, Wai Li Lim, Riksfardini A. Ermawar, Hai Yen Nguyen, Neil J. Shirley, Jelle Lahnstein, Kendall Corbin, Geoffrey B. Fincher, Vic Knauf, Rachel A. Burton (2016) “Prospecting for Energy-Rich Renewable Raw Materials: Sorghum Stem Case Study” PLOS ONE doi: 10.1371/journal.pone.0156638