Fractionation of mucilage and protein from lesquerella (Physaria fendleri) seeds

Authors: Evangelista, Roque; Hojilla-Evangelista, Milagros - Mila; Isbell, Terry; Cermak, Steven - Steve

Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only
Publication Acceptance Date: 7/27/2018
Publication Date: 9/23/2018
Citation: Evangelista, R.L., Hojillaevangelist, M.P., Isbell, T.A., Cermak, S.C. 2018. Fractionation of mucilage and protein from lesquerella (Physaria fendleri) seeds [abstract]. Association for the Advancement of Industrial Crops Annual Conference, September 23-26, 2018, London, Ontario, Canada.

Interpretive Summary:

Technical Abstract: Lesquerella (Physaria fendleri (A. Gray, O’Kane and Al-Shehbaz) is an oilseed crop belonging to the Brassicaceae (mustard) family that is native to the southwestern United States. The seed oil contains 54-60% lesquerolic (14-hydroxy-cis-11-eicosenoic) and 3-5% auricolic (14-hydroxy-11, 17-eicosadienoic) acids. Hydroxy fatty acid is used in a variety of industrial applications such as lubricants, corrosion inhibitors, engineering plastics, plasticizers, emulsifiers, and coatings. The seed also contains 30% (dry, fat-free basis) crude protein and a significant amount of seed coat mucilage. In this study, the mucilage and protein were produced as separate products, in addition to the oil. The starting lesquerella seeds had 27.8% oil, 21.5% crude protein (% N x 6.25), and 46.6% total carbohydrates. The mucilage recovered from intact whole seeds after three extractions accounted for 21.5% of the starting material and contained 1.4% oil, 9.2% crude protein, 4.1% ash, and 83.1% total carbohydrates. The removal of mucilage followed by defatting of the seed increased the protein fraction in the meal to 44%. Protein extraction yield was 10% of the mucilage-extracted, defatted meal. On the other hand, mucilage fraction recovered from pre-pressed and hexane-defatted meal was around 60.1% of starting material and contained < 0.1% oil, 24.1% crude protein, 7.5% ash, and 68.3% total carbohydrates. The mucilage fraction required reprocessing to reduce the meal solids content. The alkali extract from defatted meal did not yield any acid-precipitated protein. The sequence of mucilage and oil extraction will affect the composition and purity of the mucilage and protein produced. If lesquerella seeds are defatted first, the mucilage and protein recovery can be combined by employing alkali extraction. The soluble fraction, which contains the protein, may be separated from the extract if desired.