ARS | Publication request: Identification of acylglycerols containing dihydroxy fatty acids in castor oil by mass spectrometry

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: August 12, 2008
Publication Date: November 19, 2008
Citation: Lin, J.T. 2008. Identification of acylglycerols containing dihydroxy fatty acids in castor oil by mass spectrometry. Fourth International Symposium of Biocatalysis and Biotechnology, Taipei, Taiwan, November 19-21, 2008.

Interpretive Summary: Ricinoleate, a monohydroxy fatty acid in castor oil, has many industrial uses. Dihydroxy fatty acids have different physical and chemical properties from those of monohydroxy fatty acids and normal fatty acids, and can be used in industry for different purpose. We have identified twelve acylglycerols containing dihydroxy fatty acids in castor oil. The structures of the three dihydroxy fatty acids were proposed. Dihydroxy fatty acids have not been previously identified in higher plants and microbial culture. They can be isolated from castor oil or produced from plants for future industrial uses.

Technical Abstract: Ricinoleate, a monohydroxy fatty acid, in castor oil has many industrial uses. Dihydroxy fatty acids can also be used in industry. The C18 HPLC fractions of castor oil were used for mass spectrometry to identify the acylglycerols containing dihydroxy fatty acids. Four diacylglycerols identified were diOH18:1-diOH18:1, diOH18:2-OH18:1, diOH18:1-OH18:1 and diOH18:0-OH18:1. Eight triacylglycerols identified were diOH18:1-diOH18:1-diOH18:1, diOH18:1-diOH18:1-diOH18:0, diOH18:2-diOH18:1-OH18:1, diOH18:1-diOH18:1-OH18:1, diOH18:1-diOH18:0-OH18:1, diOH18:2-OH18:1-OH18:1, diOH18:1-OH18:1-OH18:1 and diOH18:0-OH18:1-OH18:1. The locations of fatty acids on the glycerol backbone were not determined. The structures of these three newly identified dihydroxy fatty acids were proposed as 11,12-dihydroxy-9-octadecenoic acid, 11,12-dihydroxy-9,13-octadecadienoic acid and 11,12-dihydroxyoctadecanoic acid by MS3 or MS4 of HPLC fractions of castor oil. These individual acylglycerols were at the levels of about 0.2% or less in castor oil and can be isolated from castor oil or overproduced in a oil seed plant for future industrial uses.