Nonenzymatic α-Linolenic Acid Derivatives from the Sea: Macroalgae as Novel Sources of Phytoprostanes.

Phytoprostanes, autoxidation products of α-linolenic acid, have been studied in several plant species, but information regarding the natural occurrence of this large family of biologically active oxidized lipids in macroalgae is still scarce. In this work, the free phytoprostane composition of 24 macroalgae species belonging to Chlorophyta, Phaeophyta, and Rhodophyta was determined through a recently validated UHPLC-QqQ-MS/MS method. The phytoprostane profiles varied greatly among all samples, F1t-phytoprostanes and L1-phytoprostanes being the predominant and minor classes, respectively.

Alternative and efficient extraction methods for marine-derived compounds.

Marine ecosystems cover more than 70% of the globe's surface. These habitats are occupied by a great diversity of marine organisms that produce highly structural diverse metabolites as a defense mechanism. In the last decades, these metabolites have been extracted and isolated in order to test them in different bioassays and assess their potential to fight human diseases.

New UHPLC-QqQ-MS/MS method for quantitative and qualitative determination of free phytoprostanes in foodstuffs of commercial olive and sunflower oils.

In this work, we propose a new quick and accurate analytical method by UHPLC-QqQ-MS/MS which is able to identify free phytoprostanes in olive and refined sunflower oils. The recovery provided high extraction efficiencies ranging from 102.90% to 140.

Dihomo-isoprostanes-nonenzymatic metabolites of AdA-are higher in epileptic patients compared to healthy individuals by a new ultrahigh pressure liquid chromatography-triple quadrupole-tandem mass spectrometry method.

Oxidative stress is a biochemical state in which reactive oxygen species are generated and it has been associated with pathological states including epilepsy. Therein, neuroprostanes (NeuroPs) and dihomo-isoprostanes (Dihomo-IsoPs)-a series of compounds formed nonenzymatically through free radical-induced DHA, n-6 DPA, and AdA peroxidation-are implicated in the pathophysiological status of various human neurological diseases. A new, robust, and selective analytical method for the determination of 10 NeuroPs/Dihomo-IsoPs in human urine, using solid-phase extraction and UHPLC-QqQ-MS/MS in the multiple reaction monitoring mode (using a negative electrospray ionization interface), was developed.

Box-Behnken factorial design to obtain a phenolic-rich extract from the aerial parts of Chelidonium majus L.

A Box-Behnken design (BBD) was developed to study the influence of four parameters (X1: % methanol; X2: extraction time; X3: extraction temperature; X4: solid/solvent ratio) on two responses, namely extraction yield and phenolics content of the aerial parts of Chelidonium majus L. The model presented a good fit to the experimental results for the extraction yield, being significantly influenced by X1 and X4. On the other hand a parameter reduction was necessary to run the model for phenolics content, showing that only X1 and X2 had great influence on the response.

Piper betle leaves: profiling phenolic compounds by HPLC/DAD-ESI/MS(n) and anti-cholinesterase activity.

Introduction: Piper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener.

Objective: The purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti-cholinesterase properties.

HPLC-DAD-ESI/MS(n) analysis of phenolic compounds for quality control of Grindelia robusta Nutt. and bioactivities.

The phenolic composition of herbal tea (HT) and hydromethanolic extract (HME) obtained from Grindelia robusta Nutt. was studied by HPLC-DAD-ESI/MS(n). Thirty six flavonoids and hydroxycinnamic acids were detected, from which thirty are described for the first time in this species.

Neuroprotective effect of steroidal alkaloids on glutamate-induced toxicity by preserving mitochondrial membrane potential and reducing oxidative stress.

Several evidences suggest that enhanced oxidative stress is involved in the pathogenesis and/or progression of several neurodegenerative diseases. The aim of this study was to investigate for the first time whether both extracts from tomato plant (Lycopersicon esculentum Mill.) leaves and their isolated steroidal alkaloids (tomatine and tomatidine) afford neuroprotective effect against glutamate-induced toxicity in SH-SY5Y neuroblastoma cells and to elucidate the mechanisms underlying this protection.

Assessing Jasminum grandiflorum L. authenticity by HPLC-DAD-ESI/MS(n) and effects on physiological enzymes and oxidative species.

The dried flower buds of Jasminum grandiflorum L. are widely consumed as infusion and used in traditional medicine for psychiatric disorders. It is important to have a well-established method for the chemical characterization of J.

Phenolic compounds from Jacaranda caroba (Vell.) A. DC.: approaches to neurodegenerative disorders.

Diseases affecting the central nervous system are spread throughout the world. As so, more efficient and safe neuroprotective drugs are required. The present study describes, for the first time, the phenolic composition and bioactivity of Jacaranda caroba (Vell.

Phlorotannin extracts from fucales characterized by HPLC-DAD-ESI-MSn: approaches to hyaluronidase inhibitory capacity and antioxidant properties.

Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn.

In vitro studies of α-glucosidase inhibitors and antiradical constituents of Glandora diffusa (Lag.) D.C. Thomas infusion.

Glandora diffusa (Lag.) D.C.

Bauhinia forficata Link authenticity using flavonoids profile: relation with their biological properties.

HPLC-DAD-ESI/MS(n) was used to ascertain the authenticity of two certified and two commercial Bauhinia forficata Link samples. Different flavonoids profiles were obtained, involving 39 compounds. Just kaempferol-3-O-(2-rhamnosyl)rutinoside was found in all analysed samples.

In vitro studies to assess the antidiabetic, anti-cholinesterase and antioxidant potential of Spergularia rubra.

Spergularia rubra is distributed all over the world, being its infusion used as diuretic. In spite of its large use, the antidiabetic, anti-cholinesterase and antioxidant activities of this species have not been assessed and its chemical composition is scarcely known. In the work herein a hydromethanolic extract was studied.

Structural characterization of phenolics and betacyanins in Gomphrena globosa by high-performance liquid chromatography-diode array detection/electrospray ionization multi-stage mass spectrometry.

The metabolite profiling of Gomphrena globosa inflorescences was performed by high-performance liquid chromatography-diode array detection/electrospray ionization multi-stage mass spectrometry (HPLC-DAD/ESI-MS(n)). Based on the fragmentation patterns, 24 phenolic compounds were characterized. The identified phenolics include p-coumaric and ferulic acids, quercetin, kaempferol, isorhamnetin, and hydroxylated 6,7-methylenedioxyflavone derivatives, as well as their aglycones, none of them reported before in the species.

STEROL PROFILES IN 18 MACROALGAE OF THE PORTUGUESE COAST(1).

The sterol profiles of dominant macroalgae occurring in the western Portuguese coast were evaluated. An analytical procedure, involving alkaline hydrolysis and extraction followed by separation by reversed-phase HPLC-diode array detection (HPLC-DAD), was optimized for the study of their sterols composition. The validated methodology is short in analysis time (as the compounds are determined in <20 min), sensitive, reproducible, and accurate.

High-performance liquid chromatography-diode array detection-electrospray ionization multi-stage mass spectrometric screening of an insect/plant system: the case of Spodoptera littoralis/Lycopersicon esculentum phenolics and alkaloids.

High-performance liquid chromatography-diode array detection-electrospray ionization multi-stage mass spectrometry (HPLC-DAD-ESI-MS(n)) is considered to be a very valuable tool for the characterization of compounds found in trace amounts in natural matrices, as their previous isolation and clean-up steps can be avoided. Micro-scale separation increases the potential of this analytical technique, allowing the determination of compounds in reduced samples. Spodoptera littoralis represents a major challenge to Solanaceae plants, as it is one of the most deleterious pests.

Identification of phenolic compounds in isolated vacuoles of the medicinal plant Catharanthus roseus and their interaction with vacuolar class III peroxidase: an H₂O₂ affair?

Class III peroxidases (Prxs) are plant enzymes capable of using H(2)O(2) to oxidize a range of plant secondary metabolites, notably phenolic compounds. These enzymes are localized in the cell wall or in the vacuole, which is a target for secondary metabolite accumulation, but very little is known about the function of vacuolar Prxs. Here, the physiological role of the main leaf vacuolar Prx of the medicinal plant Catharanthus roseus, CrPrx1, was further investigated namely by studying its capacity to oxidize co-localized phenolic substrates at the expense of H(2)O(2).

First report of non-coloured flavonoids in Echium plantagineum bee pollen: differentiation of isomers by liquid chromatography/ion trap mass spectrometry.

Apicultural products have been widely used in diet complements as well as in phytotherapy. Bee pollen from Echium plantagineum was analysed by high-performance liquid chromatography/photodiode-array detection coupled to ion trap mass spectrometry (HPLC-PAD-MS(n)) with an electrospray ionisation interface. The structures have been determined by the study of the ion mass fragmentation, which characterises the interglycosidic linkage in glycosylated flavonoids and differentiates positional isomers.

Tomato ( Lycopersicon esculentum ) seeds: new flavonols and cytotoxic effect.

In this study, seeds of Lycopersicon esculentum Mill. were analyzed by HPLC/UV-PAD/MS(n)-ESI. Fourteen flavonoids were identified, including quercetin, kaempferol, and isorhamnetin derivatives, with 13 of them being reported for the first time in tomato seeds.

Metabolic profiling and biological capacity of Pieris brassicae fed with kale (Brassica oleracea L. var. acephala).

Phenolic and organic acid profiles of aqueous extracts from Pieris brassicae material and the host kale (Brassica oleracea L. var. acephala) leaves were determined by HPLC/UV-DAD/MS(n)-ESI and HPLC-UV, respectively.

Inflorescences of Brassicacea species as source of bioactive compounds: A comparative study.

Two Brassica oleracea varieties (B. oleracea L. var.

New phenolic compounds and antioxidant potential of Catharanthus roseus.

Screening of the phenolic compounds from seeds, stems, leaves and petals of Catharanthus roseus (L.) G. Don (cv.

Further knowledge on barley (Hordeum vulgare L.) leaves O-glycosyl-C-glycosyl flavones by liquid chromatography-UV diode-array detection-electrospray ionisation mass spectrometry.

Thirty-seven flavonoids and a hydroxycynnamic acid have been characterized in barley leaves (Hordeum vulgare L.) by liquid chromatography-UV diode-array coupled to ion trap mass spectrometry with electrospray ionisation interface (negative mode). Their structures have been determined by the study of the ion mass fragmentation which characterizes C-glycosyl flavones and O-glycosyl-C-glycosyl flavones, and differentiates di-O-glycosyl flavones from O-diglycosyl-flavones.

HPLC-DAD-MS/MS-ESI screening of phenolic compounds in Pieris brassicae L. Reared on Brassica rapa var. rapa L.

The phenolic profiles of cabbage white butterfly ( Pieris brassicae L.; Lepidoptera: Pieridae) at different development stages (larvae, exuviae, and butterfly), its excrements, and its host plant Brassica rapa var. rapa L.