Author
Wang, Ming | |
Morris, John - Brad | |
Tonnis, Brandon | |
Pinnow, David | |
DAVIS, JERRY - University Of Georgia | |
RAYMER, PAUL - University Of Georgia | |
Pederson, Gary |
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/12/2011 Publication Date: 8/12/2011 Citation: Wang, M.L., Morris, J.B., Tonnis, B.D., Pinnow, D.L., Davis, J., Raymer, P., Pederson, G.A. 2011. Screening the entire USDA castor germplasm collection for oil content and fatty acid composition for optimum biodiesel production. Journal of Agricultural and Food Chemistry. 59(17):9250-9256. Interpretive Summary: Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors to determine the price for production and affect the key fuel properties of biodiesel. There were 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with a significant variability ranging from 37.2 – 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was comprised primarily of eight fatty acids: palmitic, stearic, oleic, linoleic, linolenic, gadoleic, ricinoleic, and dihydroxystearic acids. Significant variability on fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production. Technical Abstract: Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors to determine the price for production and affect the key fuel properties of biodiesel. There were 1033 available castor accessions collected or donated from 48 countries worldwide in the USDA germplasm collection. The entire castor collection was screened for oil content and fatty acid composition by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Castor seeds on the average contain 48.2% oil with a significant variability ranging from 37.2 – 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was comprised primarily of eight fatty acids: 1.48% palmitic (C16:0), 1.58% stearic (C18:0), 4.41% oleic (C18:1), 6.42% linoleic (C18:2), 0.68% linolenic (C18:3), 0.45% gadoleic (C20:1), 84.51% ricinoleic (C18:1-1OH), and 0.47% dihydroxystearic (C18:0-2OH) acids. Significant variability on fatty acid composition was detected among castor accessions. Ricinoleic acid (RA) was positively correlated with dihydroxystearic acid (DHSA) but highly negatively correlated with the five other fatty acids except linolenic acid. The results for oil content and fatty acid composition obtained from this study will be useful for end-users to explore castor germplasm for biodiesel production. |