Screening of the Entire USDA Castor Germplasm Collection for Oil Content and Fatty Acid Composition for Optimum Biodiesel Production

Abstract

Castor has tremendous potential as a feedstock for biodiesel production. The oil content and fatty acid composition in castor seed are important factors determining the price for production and affecting the key fuel properties of biodiesel. There are 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 significant variability ranging from 37.2 to 60.6%. Methyl esters were prepared from castor seed by alkaline transmethylation. GC analysis of methyl esters confirmed that castor oil was composed 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 in 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.

Comparative studies on several castor (Ricinus communis L.) hybrids: Growth, yields, seed oil and biomass characterization

“…The sum of oleic and linoleic acids was 7.58%, averaged overall hybrids and trials, and ranged from 7.01% (C-854, in 2014) to 8.75% (C-1008, in 2014). These results are quite in accordance with those reported by Fernández-Martínez and Velasco (2012) and Wang et al (2011) showing that the sum of these two fatty acids in castor oil was around 10%.…”

Seed coat specific weight and endosperm composition define the oil content of castor seed

“…This range is representative of the variability in seed oil content in castor germplasm. It covers 94% of the range from 37.2 to 60.6% measured in 1033 germplasm accessions of the USDA (Wang et al, 2010(Wang et al, , 2011, and it is wider than the ranges found by Velasco et al (2015) among 121 wild accession collected in Spain (from 44.6 to 54.8%) and by Rojas-Barros et al (2004) among 191 accessions obtained from the USDA germplasm collection (from 44.8 to 56.5%).…”

“…There is large natural variability in the oil content of castor seed (Rojas-Barros et al, 2004;Velasco et al, 2015;Wang et al, 2010Wang et al, , 2011, and taking advantage of such variability is the best option before attempts are made for manipulating the complex enzymatic processes and specific genetic systems. This approach is valid for many oilseeds besides castor.…”

Milk Inhibits the Biological Activity of Ricin

“…The castor bean plant Ricinus communis, which is harvested worldwide, is a major source of castor oil that can be used industrially for many purposes, including as a source for an inexpensive biodiesel fuel (1). The poisonous plant seeds are a ubiquitous and inexpensive source of the ricin toxin that can be used as a biological bioterrorism agent (2).…”