Location: Crop Germplasm ResearchTitle: Succinic acid production across candidate lignocellulosic biorefinery feedstocks
|XU, YIFENG - Texas A&M University|
|FOSTER, JAMIE - Texas A&M Agrilife|
|MUIR, JAMES - Texas A&M Agrilife|
|JESSUP, RUSSELL - Texas A&M University|
Submitted to: American Journal of Plant Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/8/2018
Publication Date: 10/11/2018
Citation: Xu, Y., Foster, J.L., Muir, J.P., Burson, B.L., Jessup, R.W. 2018. Succinic acid production across candidate lignocellulosic biorefinery feedstocks. American Journal of Plant Sciences. 9:2141-2153. https://doi.org/10.4236/ajps.2018.911155.
Interpretive Summary: Succinic acid is one of the Department of Energy's top value-added chemicals produced by plants grown for biomass. It is a chemical that can be used as a key building block for a broad range of products including biodegradable plastics, cosmetics, food ingredients, and pharmaceuticals. Recent studies reported that succinic acid synthesis and accumulation increased in bermudagrass, a warm-season perennial grass, when the grass was grown under drought stress. This indicates more succinic acid can be produced and extracted directly from biomass feedstocks when the plant is grown under adverse environmental conditions. In order to investigate this, the objectives of this research were to: 1) evaluate succinic acid content and total yield for nine candidate lignocellulosic feedstocks (pearl millet, napiergrass, pearl millet x napiergrass hybrids [PMN], annual sorghum, perennial forage sorghum, switchgrass, giant miscanthus, energy cane, and sunn hemp) when grown in the field, and 2) characterize the impact of deficit irrigation on succinic acid accumulation across these nine species under greenhouse conditions. The highest succinic acid yields (up to 556 kg ha-1) were found in PMN, napiergrass, sunn hemp, and energy cane when grown in the field. Napiergrass and PMN entries also had the highest succinic acid yields under greenhouse conditions; however, irrigation treatments did not alter succinic acid accumulation in this study. Of these nine species evaluated, napiergrass, PMN, and energy cane appeared to be the most promising biorefinery feedstocks for succinic acid recovery.
Technical Abstract: Biofuels produced from non-food lignocellulosic feedstocks have potential to replace a significant percentage of fossil fuels via high biomass yields and suitability for cultivation on marginal lands. Commercialization of dedicated lignocellulosic crops into single biofuels is hampered by conversion technology costs and low petroleum prices. Integrated biorefinery approaches, where value-added chemicals are produced in conjunction with biofuels, in contrast offer potential towards overcoming this economic disadvantage. The objective of this research was to evaluate succinic acid accumulation across candidate lignocellulosic feedstocks. Feedstock entries included pearl millet x napiergrass hybrids ("PMN"; Pennisetum glaucum [L.] R.Br. x P. purpureum Schumach.), napiergrass (P. purpureum Schumach.), annual sorghum (Sorghum bicolor [L.] Moench), pearl millet (P. glaucum [L.] R. Br.), perennial sorghum (Sorghum spp.), switchgrass (Panicum virgatum L.), sunn hemp (Crotalaria juncea L.), giant miscanthus (Miscanthus x giganteus J.M.Greef & Deuter) and energy cane (Saccharum spp. L.). Replicated field plots, as well as an independent greenhouse trial, were characterized for succinic acid content. The PMN, napiergrass, sunn hemp, and energy cane entries had greater (P=0.05) succinic acid yields, up to 556 kg ha-1, in field trials. Napiergrass and PMN entries similarly had higher succinic acid yields under greenhouse conditions; however, irrigation treatments did not alter succinic acid accumulation in this study. Napiergrass, PMN, and energy cane thus are promising biorefinery feedstocks.