Isoprostanoids quantitative profiling of marine red and brown macroalgae

Abstract

With the increasing demand for direct human and animal consumption seaweed farming is rapidly expanding worldwide. Macroalgae have colonized aquatic environments in which they are submitted to frequent changes in biotic and abiotic factors that can trigger oxidative stress (OS). Considering that isoprostanoid derivatives may constitute the most relevant OS biomarkers, we were interested to establish their profile in two red and four brown macroalgae. Seven phytoprostanes, three phytofuranes, and four isoprostanes were quantified through a new micro-LC-MS/MS method. The isoprostanoid contents vary greatly among all the samples, the ent-16(RS)-9-epi-ST-Δ-10-PhytoF and the sum of 5-F-IsoP and 5-epi-5F-IsoP being the major compounds for most of the macroalgae studied. We further quantified these isoprostanoids in macroalgae submitted to heavy metal (copper) exposure. In most of the cases, their concentrations increased after 24 h of copper stress corroborating the original hypothesis. One exception is the decrease of ent-9-L1-PhytoP content in L. digitata.

Identification and quantification of phytoprostanes and phytofurans of coffee and cocoa by- and co-products

“…The retrieved concentrations of PhytoPs in CP, CH and CPH suggest that they are valuable sources of these compounds. Our results are consistent with those found in cocoa beans (221.46-1589.83 ng g −1 ), 22 brown macroalgae (Ectocarpus siliculosus) (310 ng g −1 ), 39 and leaves, flowers and roots of different plants (43-1380 ng g −1 ), 16 and they are similar to or higher than those found in almonds (40.25-238.09 ng g −1 ), 33 musts (21.4-447.1 ng g −1 ), 34 rice bran (22.20-118.00 ng g −1 ) and white and brown rice flours (2.55-32.89 ng g −1 ), 33 Passiflora edulis Sims shell (1.3-67.6 ng g −1 ), 35 and raw green table olive fruits (5.81-9.99 ng g −1 ). 36 Dry leaves of melon plants subjected or not subjected to thermal stress (2620-3210 and 4620-6280 ng g −1 , respectively), 24 fertigated French beans (Phaseolus vulgaris) (22 641 ng g −1 ), pea (132 755 ng g −1 ), and "mangetout" (Pisum sativum spp.…”

“…These values are higher than the ones found in, e.g. dryfermentedcocoabeans (1.18to 13.13 ng g −1 ) 22 and white and brown rice flours and rice bran (0.69, 4.2, and 10.3 ng per g dw, on an average, respectively), 30 and similar to those reported in brown macroalgae (Ectocarpus siliculosus) (486 ng g −1 ), 39 but lower than those found in pea (Pisum sativum var. BGE-033620) (4258 ng g −1 ) 37 and dry leaves of melon plants subjected or not subjected to thermal stress (1960-2750 and 3250-4810 ng g −1 , respectively).…”

Non-Enzymatic Synthesis of Bioactive Isoprostanoids in the Diatom Phaeodactylum following Oxidative Stress

“…The strong impact on chloroplasts suggests increased ROS production as a combined result of the external addition of H 2 O 2 and the production of O 2 •-, H 2 O 2 , and OH • following organellar dysfunction. We evaluated the presence of isoprostanoids in the same samples by using a sensitive mass spectrometry method developed recently to analyze 24 macroalgal species (Barbosa et al, 2015;Vigor et al, 2018). We sought to determine the presence of fragmentation ion products from deprotonated molecules of PhytoP, IsoP, and NeuroP in multiple reaction monitoring mode, and their detection relied on the search for previously known structures (targeted lipidomic approach).…”

“…Samples were concentrated under nitrogen at 40°C for 30 min and reconstituted in 100 µL of mobile phase (solvent A, water with 0.1% formic acid; solvent B, acetonitrile:MeOH, 8:2 [v/v] with 0.1% formic acid; A/B ratio, 83:17) for injection. Isoprostanoids were separated as described earlier (Vigor et al, 2018). Mass spectrometry analyses were performed using an AB SCIEX QTRAP 5500 (Sciex Applied Biosystems).…”

“…Area values were normalized to the cell concentration. The concentration of the analytes was obtained by calibration curves calculated by the area ratio of the analytes and the isoprostanoid internal standard (Vigor et al, 2018).…”