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

Abstract

Castor oil has many industrial uses because of its high content (90 %) of the hydroxy fatty acid, ricinoleic acid (OH1218:19). Lesquerella oil containing lesquerolic acid (Ls, OH1420:111) is potentially useful in industry. Ten molecular species of diacylglycerols and 74 molecular species of triacylglycerols in lesquerella (Physaria fendleri) oil were identified by electrospray ionization mass spectrometry as lithium adducts of acylglycerols in the HPLC fractions of lesquerella oil. Among them were: LsLsO, LsLsLn, LsLsL, LsLn–OH20:2, LsO–OH20:2 and LsL–OH20:2. The structures of the four new hydroxy fatty acid constituents of acylglycerols were proposed by the MS of the lithium adducts of fatty acids as (comparing to those in castor oil): OH1218:29,14 (OH1218:29,13 in castor oil), OH1218:39,14,16 (OH18:3 not detected in castor oil), diOH12,1318:29,14 (diOH11,1218:29,13 in castor oil) and diOH13,1420:111 (diOH20:1 not detected in castor oil, diOH11,1218:19 in castor oil). Trihydroxy fatty acids were not detected in lesquerella oil. The differences in the structures of these C18 hydroxy fatty acids between lesquerella and castor oils indicated that the polyhydroxy fatty acids were biosynthesized and were not the result of autoxidation products.

Quantification of the Molecular Species of TAG and DAG in Lesquerella (Physaria fendleri) Oil by HPLC and MS

“…1 of Ref. [5]) can be matched exactly to Fig. 1, by comparing with the UV chromatogram (205 nm, not given here) obtained at the same run as Fig.…”

“…The seed oil of P. fendleri was obtained as in our recent report [5]. The materials, HPLC with absorbance detector, and MS used were the same as in our recent report [5]. HPLC with ELSD was as in our earlier report [7].…”

“…Triacylglycerols (TAG) in P. fendleri oil were identified by atmospheric pressure chemical ionization mass spectrometry [4]. We reported recently the identification of TAG (74 molecular species) and diacylglycerols (DAG, ten molecular species), as well as their FA constituents in the seed oil of P. fendleri using high-performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS, multiple stages) [5]. The structures of the four newly proposed hydroxy FA constituents of the AG were OH 12 18:2 9,14 , OH 12 18:3 9,14,16 , diOH 12,13 18:2 9,14 and diOH 13,14 20:1 11 [5].…”

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.…”

“…The following are the two examples of the identification of the molecular species of TAG. (Lin et al, 2009;Lin and Chen, 2010, 2013b. Table 2 is the list of the molecular species of TAG identified by MS in the HPLC fractions.…”