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Research on natural sources of polyunsaturated fatty acids (PUFAs) for both food and nutraceutical prospects has significantly grown in recent years. Some plant oils and lipid extracts contain carotenoids, xanthophylls, sterols, and/or phenolic compounds that can provoke a lipid hydroperoxides (LOOHs) overestimation when quantifying them using nonselective colorimetric assays. Herein, we have optimized a mid‐infrared method using Fourier‐transform infrared spectroscopy coupled with attenuated total reflectance (ATR) to quantify LOOHs in oils or lipid extracts. This method is based on the conversion of triphenylphosphine (TPP) to triphenylphosphine oxide (TPPO) in the presence of hydroperoxides, with a direct assessment of TPPO levels following the formation of an oil film on the ATR crystal's surface, allowing for a low detection limit of 0.5 mmol of LOOH kg−1. The concentration of oil and TPP, as well as the reaction time, were optimized. It was demonstrated that the presence of pigments, unsaponifiable compounds, phenolics, and/or PUFAs on oils, do not disrupt the analysis. Furthermore, the stoichiometry of the TPP/LOOH reaction was examined, confirming the reliability of the method in detecting various forms of hydroperoxides. An accelerated oxidation study was carried out and the hydroperoxide contents measured using TPP/TPPO were found to be comparable to those obtained using the ferric thiocyanate method. Our method offers a fast, simple, robust, and sensitive approach to accurately quantify hydroperoxides, regardless of the chemical composition of oil or lipid extracts. Practical Application: The hydroperoxide assay method outlined in this study allows for the rapid and straightforward detection of hydroperoxides in pure oil matrices. The method's elevated sensitivity facilitates the early identification of oxidation indicators in oils, especially those with significant carotenoid or xanthophyll contents since these compounds may affect the results when using methods based on colorimetric quantification of hydroperoxides. This accurate, precise, and reproducible approach requires only small quantities of test samples and chemical products, making it well suited to routine application in laboratories and industrial environments. [ABSTRACT FROM AUTHOR]

Four Deep Eutectic Solvents (DES) based on choline chloride (ChCl) and different hydrogen bond donors (1,4‐butanediol, glycerol, isosorbide, and urea) were tested as reaction medium for the immobilized Candida antarctica B (iCALB) lipase‐catalyzed esterification of fatty acids with n‐butanol. Although the strong hydrogen bonds between DES components were expected to lower their reactivity, all except urea, competed in the esterification reaction. To study the effect of acyl group donor and water, different chain length of saturated fatty acids (ranging from 6:0 to 18:0) and water content (ranging from 0, 1, 2 or 3 molar ratio of water/ChCl) were tested in the lipase‐catalyzed esterification with n‐butanol in ChCl:urea (1:2, molar ratio). When the incubation was performed in the absence of water, the shorter the fatty acid chain length, the higher the conversion. Upon water addition, a drastic increase in the esterification rate of all the fatty acids was observed and, conversely to what occurred in the anhydrous media, the longer the fatty acid chain length, the higher the conversion. Results suggest that water concentration in the DES medium possesses a multifactorial effect, as it influences the enzyme activity, the solvent viscosity, the DES structure, and the interaction between DES components, substrates, and enzymes, thus determining the efficiency and yield of the esterification reaction. [ABSTRACT FROM AUTHOR]

Infant follow‐on formulas (IFF) mimic human milk. This study aimed to identify the key structural levers that influence oxidative stability of IFF. Representative model IFF of marketed products in term of lipid composition were formulated with varying droplet size, lipid droplet core composition, and interfacial composition using different emulsifiers (soy lecithin or dairy phospholipids [DPL]). The oxidative stability of model IFF was assessed in accelerated storage conditions. No significant stabilization effect based on the lipid droplet core composition was observed. However, the nature of the interface, influenced by the emulsifier type, had an impact. Model IFF with DPL showed no loss of tocopherols and peroxide value was up to twice lower than those with soy lecithin after 20 days. This effect was particularly pronounced for the 0.4µm droplets. These results suggest that model IFF with DPL had a greater oxidative stability, likely due to the presence of sphingomyelin and the formation of a rigidified domain at the droplet surface. Model IFF with 0.4 µm droplets stabilized with soy lecithin, especially when added to the water phase, showed a tocopherols loss twice as high as that of IFF with DPL. These results indicate that oxidative stability of IFF is more influenced by the chemical environment rather than droplet size. Practical Application: Infant follow‐on formulas (IFF) aim to ensure an adequate nutritional intake to support the proper development and infant growth. Therefore, IFF must be stable against degradation phenomena such as lipid oxidation and have a composition and structure that are as biomimetic as possible to mature breast milk. This study provides key information for the development of IFF with a lipid composition and structure that are suitable for the infant nutritional needs and have an acceptable resistance to lipid oxidation. More generally, these results can be applied to all dispersed systems in the form of oil‐in‐water emulsions with a similar composition. [ABSTRACT FROM AUTHOR]

A series of hydrophobic natural deep eutectic solvents (HNADESs) have been employed to extract lupeol from lupin seed coat at 30 and 70°C. The extraction yields have been compared with those obtained with conventional organic solvents. In general, lupeol extraction yields (LEYs) obtained when using HNADES are somewhat smaller than those obtained if organic solvents are used. However, the nature of the HNADES mixtures as green solvents represents a superior performance in terms of sustainability of the extraction process. Additionally, an investigation has been carried out in order to compare the LEYs obtained when using the HNADES mixtures with those obtained if the isolated precursor compounds are employed at a temperature (70°C) where both HNADES and the corresponding precursor compounds are liquids. Surprisingly, LEYs for lupeol at 70°C were found to be, in some cases, slightly higher if the precursor compounds are used in comparison with the proper HNADES mixtures. It seems that the unique properties of the HNADES mixtures are not enough to perform better as extractants in comparison with the isolated precursor compounds at moderate temperatures, at least for the case of lupeol from lupin seed coat. Some hints are presented to explain these results. Practical Applications: The demand to use by‐products, such as raw materials, to obtain potential bioactive compounds is gaining strong attention in the last years. The use of green solvents to extract these compounds is also envisaged to obtain substances in an environment‐friendly way and with high sustainability for the economy and end‐consumers. The main aim of this work is the extraction of lupeol from lupin seed coat by using on one side different hydrophobic natural deep eutectic solvent (HNADES) mixtures, and on the other side by using the precursor compounds of the mixtures, in order to evaluate the efficiency of these green extraction solvents in the recovery of bioactive compounds with health benefits from waste material. Our results show that lupeol can be extracted both with the HNADES mixtures and with their precursor components at moderate temperatures with similar efficiency. This work questions the need of using HNADES as clean extraction solvents as the precursor compounds have themselves interesting extracting capacities. [ABSTRACT FROM AUTHOR]

Lipid oxidation is a major concern in the food, cosmetic, and pharmaceutical sectors. The degradation of unsaturated lipids affects the nutritional, physicochemical, and organoleptic properties of products and can lead to off‐flavors and to the formation of potentially harmful oxidation compounds. To prevent or slow down lipid oxidation, different antioxidant additives are used alone or in combination to achieve the best possible efficiency with the minimum possible quantities. In manufactured products, that is, heterogeneous systems containing lipids as emulsions or bulk phase, the efficiency of an antioxidant is determined not only by its chemical reactivity, but also by its physical properties and its interaction with other compounds present in the products. The antioxidants most widely used on the industrial scale are probably tocopherols, either as natural extracts or pure synthetic molecules. Considerable research has been conducted on their antioxidant activity, but results regarding their efficiency are contradictory. Here, we review the known mechanisms behind the antioxidant activity of tocopherols and discuss the chemical and physical features that determine their efficacy. We first describe their chemical reactivity linked with the main factors that modulate it between efficient antioxidant capacity and potential prooxidant effects. We then describe their chemical interactions with other molecules (phenolic compounds, metals, vitamin C, carotenes, proteins, and phospholipids) that have potential additive, synergistic, or antagonist effects. Finally, we discuss other physical parameters that influence their activity in complex systems including their specific interactions with surfactants in emulsions and their behavior in the presence of association colloids in bulk oils. [ABSTRACT FROM AUTHOR]

Rapeseed meal proteins (RP) are enzymatically hydrolyzed using three individual proteases (Alcalase, Flavourzyme, and Prolyve) and the enzymatic mechanism is studied. Rapeseed hydrolysates are produced under controlled conditions and the Prolyve hydrolysate is separated by membrane filtration. Their capacity to reduce free radicals (by transfer of hydrogen or electron) or transition metals (by electron transfer) in the absence of an oxidizable substrate, their metal chelating capacity as well as the antioxidant performances in model (conjugated autoxidizable triene assay) are investigated. All hydrolysates show a reduction capacity (by transfer of hydrogen or electron) and antioxidant activities, in a dose‐dependent manner, which are however not significantly increased in comparison to the native proteins. A noteworthy metal chelating activity of the peptides produced with Prolyve is highlighted. These results indicate the potential of valorization of RP as a source of high metal chelating peptides to counteract lipid oxidation in foods. Practical applications: Over the last decade, the antioxidative potential of peptides from plant biomass has been evidenced by much research. Considering the myriad of possible sources and the diversity of technology and means to obtain peptides from protein materials, it is reasonable to expect more applications. Concomitantly, preventing lipid oxidation, especially with the polyunsaturated fat‐based products, is a major concern in sectors such as agri‐food and cosmetic. Although the efficacy of synthetic antioxidants is recognized, both consumers and manufacturers are looking for more innovative, healthy, environmental‐friendly processes and quality products. In this context, a controlled proteolysis of proteins from plant by‐products can be used as a sustainable strategy to produce antioxidant peptides. Among them, new peptides released from rapeseed proteins with Prolyve can provide interesting metal chelators to counteract lipid oxidation in foods. [ABSTRACT FROM AUTHOR]

BACKGROUND Applications of chemical and enzymatic methods of esterification have been limited by low selectivity of chemical catalysts and low productivity and high cost of enzymes. The objective of this study was to produce eugenol esters with high productivity and selectivity using a microwave technique without adding any catalyst or solvent. Specific focus was given to reaction temperature and molar ratio to establish the kinetics and mechanism of eugenol auto‐catalytic acylation using microwave radiation. RESULTS: Reaction conversion was observed to increase in response to higher temperatures. The optimum molar ratio of eugenyl/acetic anhydride was 1:6, while the optimum molar ratio of eugenyl/butyric anhydride was 1:4.5. A high degree of selectivity (of over 97%) occurred under all conditions of the reaction. Based on modelling studies, it can be concluded that the intended reaction follows second‐order kinetics for both eugenyl acetate and eugenyl butyrate. Microwave heating at 70 °C led to an increase of rate constant by 3.71‐ and 3.83‐fold for eugenyl acetate and eugenyl butyrate, respectively, as compared to the conventional method. This was associated with a decrease in the activation energy (4.38% for eugenyl acetate and 3.11% for eugenyl butyrate) and an increase in the frequency factor (42.31% for eugenyl acetate and 49.84% for eugenyl butyrate) and entropy (4.71% for eugenyl acetate and 5.22% for eugenyl butyrate) as a result of using microwave radiation. CONCLUSIONS: The microwave technique can be considered as a green, low‐cost and quick process for auto‐catalytic production of eugenol esters. © 2020 Society of Chemical Industry (SCI) [ABSTRACT FROM AUTHOR]

Numerous different in vitro assays, labeled as "antioxidant assays," are used intensively to predict the antioxidant capacity of phenolic compounds. Most of these methods give valuable information in terms of chemical reactivities but also present some weaknesses. It may be difficult to use them to predict antioxidant capacity in real conditions. Indeed, lipid oxidation is a complex reaction, with numerous paths and components, and antioxidant action can occur via a multitude of mechanisms, especially when different phases coexist in the lipid‐based formulation. Yet, correctly combining selected in vitro methods to extract complementary information with respect to antioxidant behaviors would be much better and will help reducing the gap between prediction and efficacy in the finished product. Thus, we hereby propose a methodology to evaluate the antioxidant properties of 12 selected natural polyphenolic extracts based on the appropriate combination of in vitro assays. The scores obtained with the DPPH test, the measure of the chelation capacity, the evaluation of antioxidants efficiency in emulsions (CAT and VESICAT assays), or in bulk oils were submitted to a statistical treatment. This analysis allowed a ranking on their global antioxidant capacities and the creation of clusters depending on their mechanisms of action and the type of media where the tests were performed. [ABSTRACT FROM AUTHOR]

BACKGROUND: Coffee pulp (CP), cocoa husk (CH), and pod husk (CPH) are the main agro‐residues from coffee and cocoa industries. They are sources of useful biomolecules, such as phenolic compounds, fibers, and alkaloids, among others. In this study, different compositions of deep eutectic solvents (DES) were investigated as a green and sustainable extraction media, with respect to their extraction capacity. The extraction yields were evaluated using heat stirring‐assisted extraction (HSE) or ultrasound‐probe assisted extraction (UPAE). RESULTS: The results showed an important effect of the DES composition. Choline chloride (ChCl) based‐DES were the most effective, specifically lactic acid:ChCl (2:1 mol ratio), and the extraction capacity of DES was higher with UPAE (3 min/constant duty cycle (200 W)), in comparison with HSE (1 h/30 min). Chlorogenic acid, caffeine, and theobromine were identified as the main bioactive compounds. Interestingly, under specific conditions, DES allowed the formation of a molecule, identified as furfural by ultrahigh‐performance liquid chromatography mass spectrometry (UPLC‐MS), which could not be obtained using conventional extraction solvent (ethanol 70% v/v). CONCLUSION: DES showed a sustainability and high extraction capacity of biomolecules. In addition, their use as extraction solvents could lead to the formation and production of valuable building block molecules from plant biomass. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Hydroperoxides (LOOH) measurement is a common technique to determine the degree of oxidation of oils and fats. Although it appears to have some limitations (time consuming, and uses of toxic solvents as chloroform), the iodometric titration is one of the most common methods. Herein, an alternative method by measuring the oxidation level using Fourier transform infrared (FTIR) with an attenuated total reflectance mode (ATR), based on the stoichiometric conversion of triphenylphosphine (TPP) into triphenylphosphine oxide (TPPO) by hydroperoxides, is proposed. The FTIR‐ATR spectroscopy allows for a simple and accurate detection of the TPPO formed by selective reaction with LOOH, with measurement of its specific adsorption band at 542 cm−1. Calibration is made with TPPO solubilized in butan‐2‐one and covers a range of peroxide values (PV) from ≈2 to ≈800 mEq kg−1. The comparison of the iodometric titration and TPP/TPPO assay is performed with standard hydroperoxides (tert‐butyl hydroperoxide and cumene hydroperoxide). The iodometric titration shows higher PV overestimations in comparison with the TPP/TPPO assay, for both hydroperoxides. An accelerated oxidation of different oils is assessed with the two methods, and the results confirm this observation since higher PV values are measured with the titration method. The TPP/TPPO assay coupled with the ATR‐FTIR spectroscopy appears as a simpler and faster assay, which may limit overestimation and use of toxic solvents, especially suitable for routine analysis of oil and fats. Practical Applications: One of the first indicator of oxidation in oils and fats is the presence of hydroperoxides, therefore, it is important to find a reliable method to assess these oxidation products. One of the most common methods to determine lipid hydroperoxide (LOOH) concentrations is iodometric titration. Although this method is simple to set up, it is labor‐intensive, time consuming, and uses a lot of solvent. TPP/TPPO assay coupled with FTIR‐ATR spectroscopy is a good alternative to the iodometric method since it allows a fast and robust hydroperoxide measurement, with minimal use of organic solvents. This rapid peroxide value determination can be adapted for routine quality control analyses, especially for oxidation in real‐time and accelerated aging assays to evaluate oxidative stability during shelf‐life, for industrial purpose or lab scale experiments. The TPP/TPPO coupled with FTIR‐ATR allows for a fast, simple, reasonably sensitive (adequate for most purposes) and reproducible alternative assay to conventional iodometric titration for peroxide value assessment. [ABSTRACT FROM AUTHOR]

Despite the promising anti-oxidant and anti-inflammatory effects of resveratrol (RES) on human health, pre-clinical and clinical studies are frequently disappointing, probably due to its low water-solubility and poor bioavailability. Even though a hormetic mode of action was clearly established for RES, the high doses commonly used to mitigate these issues, lead to adverse effects. Common hallmarks of multiple pathologies results from pathological-enhanced endothelial permeability due to both enhanced inflammation and matrix metalloprotease-9 (aMMP-9) activities. The main aim of this work was to optimize the RES capacity to inhibit aMMP-9 by using a new class of solvents, natural deep eutectic solvents (NADES) for a new RES formulation as compared with dimethyl-sulfoxide (DMSO). To obtain the appropriate NADES, 18 compounds combinations were prepared to select those exhibiting the optimized capacity to dissolve RES. The RES-NADES 1,2-propanediol:choline-chloride:water (PCW, 1:1:1 molar ratio) and compared with RES-DMSO for their aMMP-9-inhibitory capacities. Low concentrations of RES-NADES/PCW formulation exhibited both a biocompatible solubility and a strong increased aMMP-9-inhibitory activity, at least 10-fold, higher than RES-DMSO, reaching its hormetic mode of action. Following in vivo validations, some particular NADES could potentially be considered as the new generation of formulation for druggable compounds. Practical applications: Formulation of resveratrol in Natural Deep Eutectic solvents (NADES) optimizes its capacity to inhibit active matrix metalloprotease-9. The Resveratrol-NADES 1,2-propanediol:choline-was the most efficient and low concentrations exhibited both a biocompatible solubility and an increased aMMP-9-inhibitory activity, at least 10-fold, higher than RES-DMSO. Consequently, the NADES/PCW formulation allowed resveratrol to reach its hormetic mode of action. Following in vivo validations, some particular NADES could potentially be considered as the new generation of formulation for druggable compounds. The effect of resveratrol (RES) dissolved in either NADES/PCW or DMSO was assessed on the TNFa-activated human monocytes (THP-1). NADES/PCW was able to confer a significant increase of the MMP-9 inhibitory activity of RES, at low doses (at least 10-fold higher) than DMSO, Thus, these data on RES-NADES/PCW formulation support the hormetic effect of resveratrol in preserving the endothelial monolayer integrity by decreasing the exacerbated vascular permeability induced by the overproduction of active MMP-9, during inflammation resulting from infections, cancer, or other pathologies. [ABSTRACT FROM AUTHOR]

Despite the evidence supporting a relationship between phenolipid's alkyl chain length and their interaction/affinity with membranes, such a connection has not been directly evaluated. In this study, the membrane interactions of rosmarinic acid, and its corresponding alkyl esters having 4 carbon (RC4), 8 carbon (RC8), 10 carbon (RC10), and 16 carbon (RC16) have been investigated via small angle X-ray scattering (SAXS) approaches in model membrane liposomes. The results of this work show significant differences between the tested phenolipids with respect to their interaction and location within the lipid bilayer. Both membrane affinity and penetration depth follow a nonlinear behavior. They have been shown to increase as a function of increasing alkyl chain length until a threshold is reached for medium alkyl chain, beyond which any lengthening of the chain results in a collapse. RC8 show the highest affinity for the membrane, whereas RC10 constitute a critical chain length from which the penetration depth decreases. The X-ray scattering analyses seem to perfectly correlate with the phenolipids' activities (antioxidant and membranes crossing) previously observed both in biological system and in formulated lipid dispersions. Practical applications: Phenolic compounds are potent antioxidants that may play an important role as well in biological system as in formulated lipid dispersions. However, their activity is often limited by low solubility or bioavailability. Lipophilization of phenolic compounds may increase their solubility in lipophilic matrices, conferring better antioxidant protection for food or nonfood application. In biological system, lipophilization may contribute to easier penetration of antioxidants through lipid bilayer of cell membranes, which can significantly increase their bioavailability. Despite the evidence supporting a relationship between phenolipid's alkyl chain length and their interaction/affinity with membranes, such a relationship has not been directly evaluated. Investigation of membrane interactions between phenolic and its lipophilic derivative, via SAXS approaches in model membrane liposomes, provide new knowledge about this class of compound with the perspective to be used as substances with maintained or improved biological properties for food, cosmetic and pharmaceutical applications. An X-ray diffraction analysis highlighted different membrane affinity and nonlinear penetration depth of a series of phenolipids (rosmarinic acid, and its corresponding alkyl esters having 4 carbon (RC4), 8 carbon (RC8), 10 carbon (RC10), and 16 carbon (RC16)). The results seem to perfectly correlate with the phenolipids' activities (antioxidant and membranes crossing) previously observed both in biological system and in formulated lipid dispersions. [ABSTRACT FROM AUTHOR]

Phenolipids correspond to the covalent grafting of a lipophilic moiety to a phenolic compound in order to modify its hydrophilic/lipophilic balance and adjust its properties. These compounds have already proven to be excellent antioxidants against lipid oxidation in heterogeneous systems such as food emulsions or cosmetic formulations. Herein, we discuss the potential of phenolipids as biological agents in cells or as new antimicrobials. [ABSTRACT FROM AUTHOR]

A series of new model of lipophilized phenolic compound derived from the rosmarinic acid was synthesized: 1,2-diacylglycerol rosmarinate (RDAG) with different alkyl chain lengths from five to eighteen carbons. These RDAG were obtained through a chemo-enzymatic synthesis: A chemical esterification based on the Mitsunobu reaction, followed by a lipase-catalyzed transesterification to link the different lipophilic moieties. The antioxidant abilities of these molecules were assessed on reactive oxygen species (ROS) overexpressing fibroblasts. The RDAG12 displayed the best antioxidant activity of the series. Lengthening of the lipid chain beyond twelve carbon atoms leads to a decrease in the antioxidant activity, thus confirming the occurrence of a cut-off effect. Antioxidant RDAG12 activity was then compared with that of vitamins C and E, rosmarinic acid and decyl rosmarinate (R10). The order of activity was R10 > RDAG12 > RDAG5 > rosmarinic acid ∼ vitamin C ∼ vitamin E. At 5 μM, R10 exhibited an even better antioxidant activity than the combination of vitamins C and E at 5 μM each. These results confirm, firstly, that catechol structure is very effective in terms of antioxidant activity and secondly, that linking an appropriate hydrophobic domain is a powerful strategy to synthesize effective antioxidants. Practical applications: Phenolic compounds (especially phenolic acids and flavonoids) are potent antioxidants that may play an important role as well in biological system (to prevent some risk factors associated with cancers, cardiovascular, and neurodegenerative diseases) as in formulated-lipid dispersions. However, their activity is often limited by low solubility and stability in such systems. Lipophilization of phenolic compounds may increase their solubility in lipophilic matrices, conferring better antioxidant protection for food or non-food application. In biological system, lipophilization may contribute to easier penetration of antioxidants through lipid bilayer of cell membranes, which can significantly increase their bioavailability. Thus, lipophilic phenolic derivatives provide a perspective of substances with maintained or improved biological properties for food, cosmetic, and pharmaceutical applications, playing an important role in the development of new drugs or food additives. A series of new model of lipophilized phenolic compound (1,2-diacylglycerol rosmarinate, RDAG) were synthesized through a chemo-enzymatic synthesis. In terms of antioxidant activity assessed in fibroblasts, all synthesized RDAG exhibited higher ROS inhibition level than free rosmarinic acid. RDAG with two lauryl chains (RDAG12) displayed the best antioxidant ability of the series, with higher activity than vitamins E and C. These results confirm that linking an appropriate hydrophobic domain is a powerful strategy to synthesize effective antioxidants. [ABSTRACT FROM AUTHOR]

The new generation of designer solvents, such as deep eutectic solvents (DES), are generally claimed to be renewable and environmentally friendly. Nevertheless, this classification depends entirely on the nature of the selected components. The DES derived from choline chloride (ChCl) combined with a safe hydrogen-bond donor, such as urea, seemed ideal for the design of eco-friendly processes. In mixtures with water, it has been successfully used for lipase-catalyzed reactions of polar substrates. However, no studies have yet examined the role of the different components involved in these mixtures (ChCl, urea, and water) in the medium's functional properties, especially in the biocatalysis field where the enzymes are very sensitive to the environment. By analyzing the water activity ( aw) and water content of the solvent, this paper reveals two different thermodynamic areas controlled by the strong association between ChCl and water. In addition, by varying the urea concentration, we show that urea has a denaturing effect on the enzyme and a positive effect on the selectivity of the reaction. Overall, this study made it possible to optimize the lipase-catalyzed alcoholysis reactions, with the synthesis of high yields of a wide range of lipophilic derivative compounds of phenolic acids. [ABSTRACT FROM AUTHOR]

Liposomes can be used as therapeutic vehicles and membrane models to mimic cells, therefore developing new efficient assays to assess membrane oxidation of liposomes is of great importance. Their bilayer structure serves as an interesting model to investigate the antioxidant potential of compounds, as well as drug–membrane interaction. In this context, a new and high‐throughput method called "Vesicle Conjugated Autoxidizable Triene (VesiCAT)" that is based on specific UV absorbance spectral properties of a phospholipid probe, is described. The membrane oxidation under constant free radical flux generated by azo initiators, either in membrane or in aqueous phase, offers the possibility of extracting different but complementary informations in addition to the antioxidants efficacy. Thus, the VesiCAT assay represents an excellent tool not only to evaluate antioxidant capacity of molecules or extracts, but also to gain knowledge on their membrane distribution and their interaction with hydrophilic or hydrophobic reactive oxygen species. Practical Applications: Several methods have been developed to measure antioxidant capacity of molecules or extracts. However, most of them neglect the complexity of real systems; especially how the coexisting phases may get involved in the antioxidant performance. Moreover, most of the assays use accelerated oxidation tests, and they do not consider the effect of free radicals location on the antioxidant response. The VesiCAT method is a fast and efficient testing assay, implemented with a microplate reader. In addition, the aforementioned testing defect are considered and evaluated, rendering a more reliable and accurate way to predict the antioxidant potential. Thus, the VesiCAT is worth to serve as new routine assay for large‐scale antioxidant analysis, for both academic and industrial purposes, in alternative to conventional ones. The VesiCAT assay may represent a routine test for antioxidant ranking, with additional information regarding the antioxidants distribution and the evaluation of their capacity to interact with oxidant species in different cell regions. [ABSTRACT FROM AUTHOR]

Many previous reports suggested that conventional antioxidant assays could not forecast antioxidant performance of plant extracts, especially when it came to a real food system such as oil‐in‐water emulsion. In this study, antioxidant activities of aqueous and ethanolic plant extracts are investigated using multiple conventional assays (TPC, ABTS, FRAP, ORAC) and the oil‐in‐water (O/W) emulsion‐based high throughput assays (the CAT and ApoCAT) in a comparison with an autoxidative O/W emulsion model monitored by formation of lipid hydroperoxide and TBARS values. Results suggest that only the ApoCAT assay is able to forecast the antioxidative performances of the extracts in O/W emulsions, regardless of the differences in extraction solvents, while the CAT assay can explain only the performance of ethanolic plant extracts in O/W emulsions. According to untargeted metabolite analysis, the antioxidants activities of plant extracts might be strongly influenced by extraction solvents. As a result, not only is the quantity of particular metabolites impacted, but also the whole metabolite (antioxidant) profiles of the extracts are modified. In addition, this study demonstrates that both the chemical reaction scheme and physical‐state of a model are important parameters for designing a better antioxidant assay in the future. Practical Applications: The ApoCAT assay would be a more practical method for screening antioxidant compounds and/or crude plant extracts than conventional antioxidant assays and the original CAT assay. The antioxidant capacity of plant extracts obtaining from the ApoCAT can be used to represent their antioxidant performances in food emulsions regardless of their extraction solvents. Several crude plant extracts using different solvents are used to validate the performance of the CAT and the ApoCAT assays in comparisons with multiple conventional antioxidant assays. These assays differ from each other in terms of scheme of reaction and physical state of the test. In addition, oil‐in‐water (O/W) emulsion model is used as a reference method representing the antioxidant activities in food matrices. Principal component analysis (PCA) is performed to better understand the relationship among all assays. The results suggest that only the ApoCAT assay exhibits a close relationship with O/W emulsion model in both crude ethanolic and aqueous plant extracts. Furthermore, putative metabolite profiles of crude plant extracts are identified using LC‐orbitrap MS/MS. Several crude plant extracts using different solvents are used to validate the performance of the CAT and the ApoCAT assays in comparisons with multiple conventional antioxidant assays. These assays differ from each other in terms of scheme of reaction and physical state of the test. In addition, oil‐in‐water (O/W) emulsion model is used as a reference method representing the antioxidant activities in food matrices. Principal component analysis (PCA) is performed to better understand the relationship among all assays. The results suggest that only the ApoCAT assay exhibits a close relationship with O/W emulsion model in both crude ethanolic and aqueous plant extracts. Furthermore, putative metabolite profiles of crude plant extracts are identified using LC‐orbitrap MS/MS. [ABSTRACT FROM AUTHOR]

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