Improved embryonic cryosurvival observed after in vitro supplementation with conjugated linoleic acid is related to changes in the membrane lipid profile.

The aim of this study was to evaluate the effect of supplementing serum-containing media with a mixture of cis- and trans-9,11- and -10,12-conjugated isomers of linoleic acid (CLA) during different steps of the in vitro production (IVM, IVC, or IVM + IVC) of bovine embryos on their embryonic development, cryotolerance, and lipid profile. To evaluate the impact of the CLA on membrane lipids, such as phosphatidylcholine (PC) and sphingomyelin (SM), the embryos' lipid profiles were obtained using matrix-assisted laser desorption ionization mass spectrometry. The cleavage rates (78.6%-84.8%) and blastocyst development (44.8%-51.2%) remained unaltered. The postthawing reexpansion rates were higher (P < 0.05) when the CLA was added to the IVM medium (82.6%) or to the IVM + IVC medium (83.8%) than the control (69.3%) or IVC medium (63.0%). Changes in the blastocysts' lipid profile occurred when supplementation was restricted to the IVM or IVC medium. However, the most prominent effects of the CLA on the embryonic PC and SM profiles were observed when the supplement was added to IVM + IVC media, which was an increase in the level of highly unsaturated PCs containing 36 or 38 carbons, which are likely to contain CLA residues. These results showed that the molecular mechanism resulting in the improved cryosurvival, observed with CLA supplementation during bovine embryonic in vitro production, was related to the composition of structural lipids of cellular membranes and is dependent on the treatment length. Monitoring the lipid profile of embryonic membranes may improve the CLA supplementation strategy and facilitate the development of new IVC systems to improve the cryopreservation of bovine embryos and those of other domestic species.

Pterodon pubescens oil: characterisation, certification of origin and quality control via mass spectrometry fingerprinting analysis.

INTRODUCTION: The oil obtained from Pterodon pubescens (Leguminosae) seeds are known to display anti-cancer, anti-dermatogenic and anti-nociceptive activitiy. Phytochemical studies have demonstrated that its main constituents are diterpenoids with voucapan skeletons. Considering the potential biological activities of the oil, rapid and efficient methods for assessing its quality would facilitate certification and quality control. OBJECTIVE: To develop a direct mass spectrometric fingerprinting method for the P. pubescens seed oil that would focus on the major diterpenoids constituents, enabling quality control, origin certification and recognition of marker species in commercially available products. METHOD: Two techniques were used: (i) direct infusion electrospray ionisation (ESI) mass spectrometry after solvent extraction and dilution and (ii) ambient desorption/ionisation via easy ambient sonic-spray ionisation, EASI(+)-MS, performed directly on the seed surface or at a paper surface imprinted with the oil. RESULTS: From a combination of ESI-MS, HRESI-MS and ESI-MS/MS data, 12 diterpenes were characterised, and typical profiles were obtained for the oil extract or the crude oil via both ESI-MS and EASI-MS. These techniques require no or very simple sample preparation protocols and the whole analytical processes with spectra acquisition take just a few minutes. CONCLUSION: Both techniques, but particularly EASI-MS, provide simple, fast and efficient MS fingerprinting methodologies to characterise the P. pubescens oil with typical (di)terpene profiles being applicable to quality control and certification of authenticity and origin.