Identification of Minor Acylglycerols Less Polar than Triricinolein in Castor Oil by Mass Spectrometry

Abstract

Acylglycerols in castor oil less polar than triricinolein were identified by electrospray ionization-mass spectrometry using the lithium adducts of the acylglycerols in the HPLC fractions of castor oil. Thirty four new molecular species of acylglycerols containing hydroxy fatty acids in castor oil were identified by MS. The chain lengths of fatty acid substituents were C16, C18, C20, C22 and C23. The numbers of double bonds of the fatty acids were from zero to three. The numbers of hydroxyl groups on the fatty acid chains were from zero to three as previously reported. The structure of fatty acid, OH18:2, was proposed as 12-hydroxy-9,13-octadecadienoic acid. An unusual odd-numbered long-chain fatty acid, 23:0 (tricosanoic acid), was identified. Some new estolides and tetraacylglycerols, were identified as (12-ricinoleoylricinoleoyl)-ricinoleoyl-linoleoyl-glycerol (RRRL), (12-ricinoleoylricinoleoyl)-ricinoleoyl-oleoyl-glycerol (RRRO), (12-ricinoleoylricinoleoyl)-ricinoleoyl-palmitoyl-glycerol (RRRP), (12-ricinoleoylricinoleoyl)-ricinoleoyl-stearoylglycerol (RRRS) and (12-ricinoleoylricinoleoyl)-ricinoleoyl-linolenoyl-glycerol (RRRLn). The normal fatty acid (non-hydroxylated) of these tetraacylglycerols were directly attached to the glycerol backbone. The biosynthetic pathway of castor oil is proposed.

Identification of TAG and DAG and their FA Constituents in Lesquerella (Physaria fendleri) Oil by HPLC and MS

“…4 of Ref. [6]) as well as the proposed fragmentation pathway of its fragment ion at m/z 219.0. The fragment ion was used to propose the location of the second double bond on OH18:2 in castor oil at C-13 as OH 12 18:2 9,13 .…”

“…We have identified ten molecular species of DAG and 74 molecular species of TAG in Physaria fendleri oil ( Table 1). Using the same method, we previously identified 13 DAG and 66 TAG in castor oil [6,12,16,19,20]. Byrdwell for the identification of TAG from Physaria fendleri oil [10].…”

“…We have recently reported the hydroxy FA biosynthesis and lipid gene expression during seed development in Physaria fendleri [5]. We have also recently proposed the biosynthetic pathway of castor oil [6].…”

High-resolution Kendrick Mass Defect Analysis of Poly(ethylene oxide)-based Non-ionic Surfactants and Their Degradation Products

“…4C . In addition to the x, y ion series with y 0-4, several point clouds are now properly highlighted and assigned to polyglycerol polyricinoleate side products 23 formally x, y 0-3 glycerol, noted a-d and stearate-containing byproducts formally x, y 0-2 stearate, noted g-i . As for PEO monostearate , using a fractional base unit with a divisor set close to the nominal mass of the repeat unit expands the KMD dimension in a controlled manner and ion series are satisfactorily separated y 1 vs. y 0 stearate: ΔKMD 0.0146 with EO and ΔKMD 0.3779 with EO/43, gain of resolution x26 .…”

Identification of molecular species of polyol oils produced from soybean oil by Pseudomonas aeruginosa E03-12 NRRL B-59991

“…There are 26 monohydroxy FA in Table 1. We have previously identified many polyhydroxy FA in castor and lesquerella oils and the FA structures have been elucidated (Lin et al, 2009;Lin and Chen, 2010, 2012, 2013b.…”