Free fatty acid profiling in marine algae extract by LC‐MS/MS and isolation as well as quantification of the ω‐3 fatty acid hexadeca‐4,7,10,13‐tetraenoic acid

Abstract

Undaria pinnatifida (Wakame) alga contains high amounts of hexadeca‐4Z,7Z,10Z,13Z‐tetraenoic acid which was reported to decrease the efficiency of cisplatin chemotherapeutics. To obtain a fatty acid enriched extract of this ω‐3 poly‐unsaturated fatty acid as an analytical standard, Wakame was used as source material for its extraction. A two‐step extraction protocol consisting of a liquid‐liquid extraction followed by solid‐phase extraction with 3‐aminopropyl silica in accordance to a normal‐phase elution mode was developed. An ultra high performance liquid chromatography with electrospray ionization tandem mass spectrometry method based on sequential windowed acquisition of all theoretical fragment ion mass spectra allowed a simultaneous comprehensive group selective fatty acids profiling in untargeted manner and quantitative analysis of the targeted fatty acid. Hexadeca‐4Z,7Z,10Z,13Z‐tetraenoic acid was identified using high‐resolution product ion spectra. The quantitative method was based on d5‐deuterated hexadeca‐4Z,7Z,10Z,13Z‐tetraenoic acid which was employed as surrogate calibrant. Preliminary method validation was performed by evaluating detection and quantification limits, linear range, intra‐assay and inter‐day precision. Finally, a concentration of 421.2 ± 14.9 ng/mL (4% CV) of hexadeca‐4Z,7Z,10Z,13Z‐tetraenoic acid was determined in the extract which was further used as analytical standard.

Recent advances in the bioanalytical methods of polyethylene glycols and PEGylated pharmaceuticals

“…Multiple reaction monitoring (MRM) based on LC–MS/MS (LC–MRM) is a “gold standard” for the bioanalysis of small molecules [168–181]. MRM assay is a target MS technique based on ESI–MS [182–191]. The operating principle composes following stages: in the first quadrupole (Q1), an analyte ion with certain mass will be selected; the selected ions will be consequently fragmentized by collision‐induced dissociation (CID); a single or multiple specific fragment ions are selected again by the second quadrupole (Q2) and transmitted into the third quadrupole (Q3) for detection (Figure 5I) [192–197].…”

Ensuring the future of functional foods

“…Microalgal fats contain polyunsaturated fatty acids (PUFAs) with high market value (Gateau et al ., ; Udayan et al ., ; Chen et al ., ), such as eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), gamma linolenic acid (GLA) and arachidonic acid (AA). These PUFAs encompass both ω‐3 and ω‐6 fatty acids that are commonly associated with fish oil (Scrimgeour & Traynor, ; Steinrücken et al ., ; Schlotterbeck et al ., ; Schmid et al ., ). However, fish do not produce these fatty acids, they accumulate these oils through their diet of plankton and microalgae and should therefore be acceptable to vegan diets (Koller et al ., ), furthermore, a commonly used microalgal species, Chlorella sp.…”

Assessing diatom-mediated fatty acids in intertidal biofilm: a new conservation concern

“…There are numerous publications listing LC parameter choices including the LC column, mobile phases, and eluent gradients that have achieved separation of fatty acids. Chu et al (2009), Samburova et al (2013), andSchlotterbeck et al (2018) are examples of literature that describe the use of ultra and ultra-high performance liquid chromatography to study fatty acids, with Schlotterbeck et al (2018) describing methods for both targeted and untargeted analysis. The LC parameters used in these papers are summarized in Table 4 for the benefit of future researchers.…”

“…However, as biofilm is highly labile and logistically challenging to collect, experiments based on biofilm sampling from mudflats need to consider a complex array of spatial-temporal factors, as well as issues including fatty acid sample degradation, and dewatering. For analysis of the samples, an array of techniques exists, including gas chromatography-flame ionization detection (GC/FID) with derivatization (Alfaro et al 2006;Quinn et al 2017;Schnurr et al 2019Schnurr et al , 2020, gas chromatography-mass spectrometry (GC/MS) with derivatization (Dahl et al 2000(Dahl et al , 2003Bergamino et al 2014), liquid chromatography-mass spectrometry (LC/MS) (Schlotterbeck et al 2018;Pérez-Navarro et al 2019), liquid chromatography-quadrupole time of flight (LC/QTOF) (Nguyen et al 2015;Molina-Calle et al 2017), and Fourier transform infrared spectroscopy (FT/IR) (Karunathilaka et al 2017;Aryee et al 2009;Gieroba et al 2020). Each technique has a different practicality and suitability for analysing complex mixtures of fatty acids.…”