A rapid validated UHPLC-PDA method for anthocyanins quantification from Euterpe oleracea fruits

In vitro assessment of the genotoxic and cytotoxic effects of clarified açai (Euterpe oleracea MART) extract in a gastric cancer cell line (AGP01 cells)

Açaí (Euterpe oleracea MART) is a fruit of great importance for the Amazon region in nutritional, cultural and socioeconomic terms. In recent years, açaí has been the subject of several studies due to its beneficial properties for health, including effects against tumor cells. Therefore, the present work aimed to evaluate in vitro the genotoxic and cytotoxic effects of the clarified extract of açaí juice in a human metastatic gastric cancer cell line (AGP01 cells). For comparison purposes, a non-transformed cell line of African green monkey renal epithelial cells (VERO cells) was used. The viability assay by resazurin reduction, the comet assay, the determination of cell death by differential fluorescent dyes and the wound healing migration assay were performed. A reduction in viability was observed only in the AGP01 line within 72 h. There was no genotoxic damage or cell death (through apoptosis or necrosis) in any of the cell lines. However, açaí extract induced motility reduction in both cell lines. The reduction in cell viability and the induction of the anti-migratory effect in the AGP01 cell line opens perspectives for exploring the potential of açaí as an adjuvant in the treatment of gastric cancer.

Açai (Euterpe oleracea Mart.) supplementation promotes histological and ultrastructural changes in rats' alveolar bone

The açai juice contains high concentrations of phenolic compounds, including cyanidin-3-glucoside and others flavonoids. The aim of this study was to evaluate the impact of açai supplementation on healthy mandibular alveolar bone in male albino rats of the Wistar strain. 24 rats were divided into 3 groups, in which one group received a daily dose of saline solution and the other two groups were treated with daily doses of clarified açai juice for 14 or 28 days. After the experiment, hemimandibles were collected and analyzed using Scanning Electron Microscopy (SEM), histological assessments, and micro-CT. Results showed changes in the integrity of the alveolar bone as seen in SEM, increased osteocyte density and higher collagen matrix area in the açai group compared to the control group as seen in histological analysis, and increased bone volume, trabecular thickness and number, and cortical bone as seen in micro-CT analysis. The space between bone trabeculae showed no difference among the groups. These results suggest that açai supplementation may have a structural change effect on alveolar bone, but further research is needed to confirm these findings in humans and to determine the exact mechanisms behind these effects.

Chemical constituents of açai berry pulp (Euterpe oleracea Mart.) by LC-UV-BPSU/NMR and LC-UV-SPE/NMR

The techniques LC-UV-BPSU and LC-UV-SPE/NMR were applied for the first time in the analysis of açai berry (Euterpe oleracea Mart.) pulp extracts. Those techniques allowed the identification of twenty-three metabolites: Valine (1), citric acid (2), tachioside (3), isotachioside (4), α-guaiacylglycerol (5), syringylglycerol (6), uridine (7), adenosine (8), dimethoxy-1,4-benzoquinone (9), koaburaside (10), protocatechuic acid (11), eurycorymboside B (12), 7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-β-D-glucopyranoside (13), orientin (14), homoorientin (15), dihydrokaempferol-3-glucoside (16), isolariciresinol-9'-O-β-D-glucopyranoside (17), 5'-methoxyisolariciresinol-9'-O-β-D-glucopyranoside (18), cyanidin-3-O-glucoside (19), cyandin-3-O-rutenoside (20), 9,12-octadecadienoic acid (Z,Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester (21), linolenic acid (22), and 1,2-di-O-α-linolenoyl-3-O-β-D-galactopyranosyl-sn-glycerol (23). In this plant, compounds 3, 4, 5, 6, 8, 10, 12, 17, 18, 21, and 23 are reported for the first time. All the structures were determined through extensive analyses of 1D and 2D NMR data, mass spectrometry, and comparison with published data. This methodology has proven to be an efficient alternative to the analysis of complex extracts containing a large variety of compounds.

Method development and validation for analysis of microencapsulated cyanidin-3-O-rutinoside in dairy samples containing juçara palm fruit by high-performance liquid chromatography

Euterpe edulis is a plant native of Brazil and popularly known as juçara. The aim of this study was to develop and validate an analytical method using high-performance liquid chromatography (HPLC) of juçara crude extracts (JCEs) and to evaluate dairy products containing free and microencapsulated extracts. The validated analytical method for JCE was performed using cyanidin-3-O-rutinoside (C3R - isolated and identified as major component from JCE) as a reference: linearity was obtained using ten concentrations between 25 and 250 μg mL-1 (R2  = 0.994); limits of detection and quantification were 19.04 μg mL-1 and 57.7 μg mL-1 respectively; accuracy (relative standard deviation) was <5%; recovery was 104.85 μg mL-1 ; and the method is robust. Physicochemical analyses of the dairy products were evaluated using colour, pH, and concentration of anthocyanins using HPLC calculated as C3R over 21 days of storage. The pH remained stable until the end of the test. The colour and the concentration of anthocyanins remained stable for 9 days. C3R was isolated, the HPLC method was developed and validated, and the colour stability was not altered until 9 days. © 2023 Society of Chemical Industry.

Oral Treatment with the Extract of Euterpe oleracea Mart. Improves Motor Dysfunction and Reduces Brain Injury in Rats Subjected to Ischemic Stroke

Ischemic stroke is one of the principal causes of morbidity and mortality around the world. The pathophysiological mechanisms that lead to the formation of the stroke lesions range from the bioenergetic failure of the cells and the intense production of reactive oxygen species to neuroinflammation. The fruit of the açaí palm, Euterpe oleracea Mart. (EO), is consumed by traditional populations in the Brazilian Amazon region, and it is known to have antioxidant and anti-inflammatory properties. We evaluated whether the clarified extract of EO was capable of reducing the area of lesion and promoting neuronal survival following ischemic stroke in rats. Animals submitted to ischemic stroke and treated with EO extract presented a significant improvement in their neurological deficit from the ninth day onward. We also observed a reduction in the extent of the cerebral injury and the preservation of the neurons of the cortical layers. Taken together, our findings indicate that treatment with EO extract in the acute phase following a stroke can trigger signaling pathways that culminate in neuronal survival and promote the partial recovery of neurological scores. However, further detailed studies of the intracellular signaling pathways are needed to better understand the mechanisms involved.

Advances in the Chemistry, Analysis and Adulteration of Anthocyanin Rich-Berries and Fruits: 2000-2022

Anthocyanins are reported to exhibit a wide variety of remedial qualities against many human disorders, including antioxidative stress, anti-inflammatory activity, amelioration of cardiovascular diseases, improvement of cognitive decline, and are touted to protect against neurodegenerative disorders. Anthocyanins are water soluble naturally occurring polyphenols containing sugar moiety and are found abundantly in colored fruits/berries. Various chromatographic (HPLC/HPTLC) and spectroscopic (IR, NMR) techniques as standalone or in hyphenated forms such as LC-MS/LC-NMR are routinely used to gauge the chemical composition and ensure the overall quality of anthocyanins in berries, fruits, and finished products. The major emphasis of the current review is to compile and disseminate various analytical methodologies on characterization, quantification, and chemical profiling of the whole array of anthocyanins in berries, and fruits within the last two decades. In addition, the factors affecting the stability of anthocyanins, including pH, light exposure, solvents, metal ions, and the presence of other substances, such as enzymes and proteins, were addressed. Several sources of anthocyanins, including berries and fruit with their botanical identity and respective yields of anthocyanins, were covered. In addition to chemical characterization, economically motivated adulteration of anthocyanin-rich fruits and berries due to increasing consumer demand will also be the subject of discussion. Finally, the health benefits and the medicinal utilities of anthocyanins were briefly discussed. A literature search was performed using electronic databases from PubMed, Science Direct, SciFinder, and Google Scholar, and the search was conducted covering the period from January 2000 to November 2022.

Açaí (Euterpe oleracea Mart.) Attenuates Oxidative Stress and Alveolar Bone Damage in Experimental Periodontitis in Rats

Açaí (Euterpe oleracea Mart.) juice is rich in phenolic compounds with high antioxidant capacity. It has been observed that the use of antioxidants may be an additional strategy to nonsurgical periodontal therapy as well as to prevent alveolar bone loss. Thus, the objective of this study was to investigate the effects of açaí supplementation on experimental periodontitis in rats. Twenty male Rattus norvegicus (Wistar) rats were assigned into control, açaí, experimental periodontitis, and experimental periodontitis with açaí supplementation groups. Periodontitis was induced by placing ligatures around the lower first molars. Animals in the açaí groups received 0.01 mL/g of clarified açaí juice for 14 days by intragastric gavage. At the end of the experimental period, blood was collected to assess the reduced glutathione (GSH), Trolox equivalent antioxidant capacity (TEAC), and lipid peroxidation (TBARS) levels. Moreover, hemimandibles were analyzed by micro-computed tomography (micro-CT) for alveolar bone loss and bone quality. Açaí supplementation increased blood total antioxidant capacity and decreased lipid peroxidation. It also reduced alveolar bone loss when compared to the experimental periodontitis group. Moreover, clarified açaí per se modulated the oxidative biochemistry and bone microstructure. Thus, açaí may be considered a viable alternative for managing periodontal oxidative stress and preventing alveolar bone loss.

Antiangiogenic and Antioxidant In Vitro Properties of Hydroethanolic Extract from açaí (Euterpe oleracea) Dietary Powder Supplement

The Euterpe oleracea fruit (açaí) is a promising source of polyphenols with health-promoting properties. To our knowledge, few studies have focused on the influence of açaí phytochemicals on angiogenesis, with a significant impact on cancer. This study aimed at investigating the phytochemical profile of a purple açaí hydroethanolic extract (AHE) obtained from a commercial dietary powder supplement by high-performance liquid chromatography coupled to diode array detection and electrospray ionization mass spectrometry, and evaluate its in vitro effects on distinct angiogenic steps during vessel growth and on oxidative markers in human microvascular endothelial cells (HMEC-1). The phenolic profile of AHE revealed the presence of significant levels of anthocyanins, mainly cyanidin-3-O-rutinoside, and other flavonoids with promising health effects. The in vitro studies demonstrated that AHE exerts antiangiogenic activity with no cytotoxic effect. The AHE was able to decrease HMEC-1 migration and invasion potential, as well as to inhibit the formation of capillary-like structures. Additionally, AHE increased antioxidant defenses by upregulating superoxide dismutase and catalase enzymatic activities, accompanied by a reduction in the production of reactive oxygen species. These data bring new insights into the potential application of angiogenic inhibitors present in AHE on the development of novel therapeutic approaches for angiogenesis-dependent diseases.

Effective determination of the principal non-psychoactive cannabinoids in fiber-type Cannabis sativa L. by UPLC-PDA following a comprehensive design and optimization of extraction methodology

Cannabidiol (CBD) and cannabidiolic acid (CBDA) represent the most abundant non-psychoactive cannabinoids in fiber-type Cannabis sativa L. (hemp) and both have demonstrated high therapeutic potential. Hence, efficient extraction coupled with reliable determination of these compounds is crucial for informed utilization of hemp and is increasingly needed in the present state of harmonization efforts. In this context, a systematic approach for extraction optimization was followed, which initially involved comparison of three widely available extraction techniques, i.e. ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and dynamic maceration (DM). These were applied on samples of different hemp varieties (n = 3) using ethanol as a safe and efficient solvent. UAE showed the most promising results and was further optimized by means of response surface methodology (RSM), based on a circumscribed central composite design. The conditions maximizing CBD, CBDA, and total CBD content as well as extraction yield were determined with high desirability (0.97) and were experimentally confirmed. The optimized UAE method was also compared with a previously reported extraction procedure, demonstrating superior performance. For the quantitation of CBD and CBDA in hemp extracts, a reversed-phase UPLC-PDA method was developed and validated. Chromatographic separation was achieved in less than 10 min, while satisfactory results for linearity (R² > 0.996), precision (RSD < 2.0%), and accuracy (recovery rates of 93.1-101.0%) were obtained for both analytes. Limits of detection were determined as 0.07 and 0.04 μg mL^-1 for CBD and CBDA, respectively, indicating sufficient sensitivity. The good performance of the method was verified by the evaluation of additional parameters (e.g. matrix effect, extraction recovery), which was largely enabled by the use of isolated standards. The whole analytical workflow, involving both optimized UAE extraction and UPLC-PDA determination, entails simplified manipulation and may offer a reliable and cost-effective approach for routine quality control of hemp regarding the principal cannabinoids.

Validated liquid chromatography separation methods for identification and quantification of anthocyanins in fruit and vegetables: A systematic review

Food composition data are challenged by data availability and quality. Anthocyanins are the bright colored pigments found in fruits and vegetables with growing evidence for health benefits. For the estimation of anthocyanin content in the foods, it is imperative to find an ideal analytical method. To quantify anthocyanin components, liquid chromatography-based methods are commonly used. This review addresses the variability of liquid chromatography (LC) mass spectrometry (MS) methods for the identification and quantification of anthocyanins. Published studies for all years until February 2020 reporting LC methods for anthocyanins in fruits and vegetables were screened from 7660 studies. Only 29 studies met the eligibility criteria of method type and of these, only 13 studies reported a validated LC method. A wide range of validation parameters were identified including specificity, calibration, stability, and limits of detection. Differences in the sampling amounts for extraction were observed in all of the included studies. The quantification of multiple anthocyanin types without their corresponding analytical standards was observed in eight studies. The included 13 studies used reverse phase liquid chromatography separation with C₁₈ type or similar stationary phases and acidified aqueous or acidified aqueous: organic (usually methanol or acetonitrile) binary gradient mobile phases. Although all of the studies used mass spectrometry for identification, ultraviolet absorbance quantification was often used in conjunction with a photo-diode array (DAD/PDA) detector using reference standards where available. Extraction and preparation of samples remains the key concern for analysis as the oxidative stability of anthocyanins are a major impediment for accurate quantification of the components in foods. This review provides a summary of validated LC methods to assist analysts and nutritionists in the quantification of anthocyanin food components as the nutrient profiles of foods are challenged by the variability of the analytical methods.

Açaí berries (Euterpe oleracea Mart.) dried extract improves ethanol-induced ulcer in rats

OBJECTIVES

Açaí (Euterpe oleracea) is widely consumed in Brazil and known for its numerous health-beneficial properties. This study investigated the gastroprotective potential of the dried açaí berries extract (DAE).

METHODS

Dried açaí berries extract effect was evaluated against ethanol-induced gastric ulcer in rats. Its ability to regulate antioxidant defenses and reduce inflammatory parameters was evaluated in the ulcerated tissues. The scavenger capability of DAE was assessed by DPPH assay, and phytochemical composition was accessed by UHPLC.

KEY FINDINGS

The extract showed radical scavenger activity in vitro (IC₅₀  = 210 µg/ml) and gastroprotective effect in vivo, reducing the ulcerated area by 83%, 67% and 48% at doses of 30 and 100 mg/kg (p.o) and 3 mg/kg (i.p), respectively, compared with vehicle group. Besides, DAE (100 mg/kg, p.o) increased the GSH content and GST activity in ulcerated mucosa. Animals treated with DAE showed normalized levels of SOD activity, elevated CAT activity and decreased MPO activity, as well as reduced TNF-α levels, compared with vehicle group. Peonidin-3-glucoside, peonidin-3-rutinoside, cyanidin-3,5-hexoside-pentoside, cyaniding-3-glucoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside were identified in DAE.

CONCLUSIONS

Our findings suggest that DAE reduces the inflammation and maintains the oxidative balance of gastric mucosa, therefore being a promising natural resource or useful nutraceutical to protect gastric mucosa.

Towards Therapeutic Alternatives for Mercury Neurotoxicity in the Amazon: Unraveling the Pre-Clinical Effects of the Superfruit Açaí (Euterpe oleracea, Mart.) as Juice for Human Consumption

Methylmercury (MeHg) exposure is a serious problem of public health, especially in the Amazon. Exposure in riverine populations is responsible for neurobehavioral abnormalities. It was hypothesized that consumption of Amazonian fruits could protect by reducing mercury accumulation. This work analyzed the effects of commercial samples of Euterpe oleracea (EO) for human consumption (10 μL/g) against MeHg i.p. exposure (2.5 mg/Kg), using neurobehavioral (open field, rotarod and pole tests), biochemical (lipid peroxidation and nitrite levels), aging-related (telomerase reverse transcriptase (TERT) mRNA expression) and toxicokinetic (MeHg content) parameters in mice. Both the pole and rotarod tests were the most sensitive tests accompanied by increased lipid peroxidation and nitrite levels in brains. MeHg reduced TERT mRNA about 50% demonstrating a strong pro-aging effect. The EO intake, similar to that of human populations, prevented all alterations, without changing the mercury content, but avoiding neurotoxicity and premature aging of the Central Nervous System (CNS). Contrary to the hypothesis found in the literature on the possible chelating properties of Amazonian fruits consumption, the effect of EO would be essentially pharmacodynamics, and possible mechanisms are discussed. Our data already support the regular consumption of EO as an excellent option for exposed Amazonian populations to have additional protection against MeHg intoxication.

Clarified Açaí (Euterpe oleracea) Juice as an Anticonvulsant Agent: In Vitro Mechanistic Study of GABAergic Targets

Seizures affect about 50 million people around the world. Approximately 30% of seizures are refractory to the current pharmacological arsenal, so, the pursuit of new therapeutic alternatives is essential. Clarified Euterpe oleracea (EO) juice showed anticonvulsant properties similar to diazepam in an in vivo model with pentylenetetrazol, a GABA_A receptor blocker. This study investigated the effects of EO on the main GABAergic targets for anticonvulsant drugs, analyzing the effect on the GABA receptor's benzodiazepine and picrotoxinin binding sites and the GABA uptake. Primary cultures of cortical neurons and astrocytes were treated with EO (0–25%) for up to 90 min. [³H]Flunitrazepam and [³H]TBOB binding, [³H]GABA uptake, cell viability, and morphology were assayed. Nonlethal concentrations of EO increased agonist binding and decreased antagonist binding in cortical neurons. Low concentrations significantly inhibited GABA uptake, especially in astrocytes, suggesting an accumulation of endogenous GABA in the synaptic cleft. The results demonstrate, for the first time, that EO can improve GABAergic neurotransmission via interactions with GABA_A receptor and modulation of GABA uptake. Understanding these molecular mechanisms will help in the treatment of seizures and epilepsy, especially in developing countries where geographic isolation and low purchasing power are the main barriers to access to adequate treatment.

Extraction techniques and analysis of anthocyanins from food sources by mass spectrometry: An update

This article reviews recent developments in methods of sample preparation and analytical methodologies for the quantification of anthocyanins and their extraction from food sources. Various methods for sample extraction and purification are highlighted and evaluated. The use of UV-diode array, along with improved liquid chromatography (LC) and mass spectrometry (MS) and/or the combination of both methods have facilitated the identification of analytes. The use of one-dimensional and two-dimensional HPLC has significantly improved resolution with a shorter amount of time. Other LC × LC combinations to improve orthogonality are also discussed. The most efficient anthocyanin extraction method from food sources is pressurized liquid extraction. Moreover, electrospray ionization (ESI) and MS²/time-of-flight are currently the most popular instruments used for identification of anthocyanins; being positive mode of ESI the most widely used procedure for anthocyanin identification. Several databases for mass spectrometry polyphenol identification have been described for reference.

Determination of anthocyanins and non-anthocyanin polyphenols by ultra performance liquid chromatography/electrospray ionization mass spectrometry (UPLC/ESI-MS) in jussara (Euterpe edulis) extracts

This work aimed to propose two analytical methods for the quantitative and qualitative analysis of major anthocyanins and non-anthocyanin phenolic compounds in jussara (Euterpe edulis) extracts, using ultra performance liquid chromatography-mass spectrometry. These methods were evaluated for selectivity, precision, linearity, detection and quantification limits. The complete separation of 5 anthocyanins and 22 non-anthocyanins polyphenols was achieved in 4.5 and 7 min, respectively. Limits of detection ranged from 0.55 to 9.24 µg/L, with relative standard deviation for concentration up to 7.0%. In jussara extract, 13 of the 27 analytes were characterized. The dominant compound was cyanidin-3-O-rutinoside, representing about 73% of the total phenolic compounds content (approximately 23 mg/g of extract in dry weight). Other phenolic compounds found in the extract were: cyanidin-3-O-glucoside, pelargonidin-3-O-glucoside, quercetin, rutin, myricetin, kaempferol, kaempferol-3-O-rutinoside, luteolin, apigenin, catechin, ellagic acid and 4,5-dicaffeoylquinic acid.

Polyphenolic composition and antioxidant activity of açai (Euterpe oleracea Mart.) from Colombia

Berries of Colombian Euterpe oleracea Mart. were analyzed for total phenolic content (TPC), anthocyanin (ACN) content, and antioxidant activity. Additionally, reversed-phase ultra-high performance liquid chromatography with photodiode array detection (RP-UHPLC-PDA) and heated electrospray ionization (HESI) multistage mass spectrometry (MS(n)) were used to determine the composition of phenolic compounds. Anthocyanin content was 0.57±0.39mg cyanidin-3-glucoside/g fresh weight (FW) and TPC was 6.07±2.17mg gallic acid equivalent (GAE)/g FW. The ABTS radical scavenging activity was 3.1±1.3μmol Trolox equivalents (TE)/100g FW, whereas the DPPH value was 2693.1±332.8μmol TE/100g FW. Overall, results show that Colombian açai has a more diverse polyphenolic profile and higher antioxidant activity than Brazilian açai. This information could be useful in authentification procedures to differentiate Brazilian açai from Colombian açai when used as an alternative for the supply of this fruit during the time of shortage in Brazil.

Rapid and sensitive method for analysis of nitrate in meat samples using ultra performance liquid chromatography-mass spectrometry

A sensitive and selective ultra performance liquid chromatography-mass spectrometric method has been developed for the quantitative analysis of nitrate in meat samples. Selected ion reaction (SIR) mode was adopted to identify and quantify the nitrate. Chromatographic analyses were performed on a BEH C-18 column with a mobile phase consisting of a surfactant (Cetylpyridinium chloride) and acetonitrile in equal ratio (50/50, v/v) at a flow rate of 0.4 mL min(-1). The limit of detection and limit of quantitation of the developed method was found to be 0.0599 and 0.1817 mg kg(-1), respectively. The linearity of the proposed method was checked in the concentration range of 0.5-10 mg kg(-1) with an excellent correlation coefficient (r) of 0.997. The recovery of the nitrate in the meat samples were in the range of 98.02-98.99%.

Development and validation of a liquid chromatography method for anthocyanins in strawberry (Fragaria spp.) and complementary studies on stability, kinetics and antioxidant power

A RPLC-DAD method for the analysis of eight anthocyanins was developed, validated and applied to strawberry extracts. The chromatographic method was conducted under gradient elution in acidulated water-methanol mobile phase and octadecyl-silica columns. An ultrasound extraction procedure was optimized by a 3(2) factorial design (%HCl in methanol, temperature, and time) and response surface methodology. Method validation was performed according to the following parameters: linearity (R(2)>0.99, p-value<10(-4), F>725), LOD (3-7 μmol L(-1)) and LOQ (9-22 μmol L(-1)), selectivity/specificity (baseline separation of all analytes and peak purity), instrumental precision (<6.4%CV), repeatability (<6.3%CV) and intermediate precision (<9.9%CV), recovery (83-99%), robustness (mobile phase pH, column temperature and flow rate) and stability (high temperatures and storage; 1st order kinetics). The antioxidant power of anthocyanins was measured on-line (ABTS(+) reaction; Trolox as reference). Ten strawberry extracts were quantified (average values: 24.2 μg/g for cyanidin-3-glucoside and 49.1 μg/g for pelargonidin-3-glucoside).

Characterization of Pterocarpus erinaceus kino extract and its gamma-secretase inhibitory properties

ETHNOPHARMACOLOGICAL RELEVANCE

The aqueous decoction of Pterocarpus erinaceus has been traditionally used in Benin against memory troubles.

AIM OF THE STUDY

New strategies are needed against Alzheimer׳s disease (AD), for, to date, AD treatment is symptomatic and consists in drugs treating the cognitive decline. An interesting target is the β-amyloid peptide (Aβ), whose accumulation and progressive deposition into amyloid plaques are key events in AD aetiology. Identifying new and more selective γ-secretase inhibitors or modulators (none of the existing has proven so far to be selective or fully efficient) appears in this respect of particular interest. We studied the activity and mechanisms of action of Pterocarpus erinaceus kino aqueous extract, after the removal of catechic tannins (KAST).

METHODS AND RESULTS

We tested KAST at non-toxic concentrations on cells expressing the human Amyloid Precursor Protein (APP695), as well as on primary neurons. Pterocarpus erinaceus extract was found to inhibit Aβ release in both models. We further showed that KAST inhibited γ-secretase activity in cell-free and in vitro assays, strongly suggesting that KAST is a natural γ-secretase inhibitor. Importantly, this extract did not inhibit the cleavage of Notch, another γ-secretase substrate responsible for major detrimental side effects observed with γ-secretase inhibitors. Epicatechin was further identified in KAST by HPLC-MS.

CONCLUSION

Pterocarpus erinaceus kino extract appears therefore as a new γ-secretase inhibitor selective towards APP processing.

Amazon acai: chemistry and biological activities: a review

Acai (acai or assai) is one of the Amazon's most popular functional foods and widely used in the world. There are many benefits to its alleged use in the growing market for nutraceuticals. The acai extracts have a range of polyphenolic components with antioxidant properties, some of those present in greater quantity are orientin, isoorientin and vanillic acid, as well as anthocyanins cyanidin-3-glucoside and cyanidin-3-rutinoside. The presence of these substances is linked mainly to the antioxidant, anti- inflammatory, anti-proliferative and cardioprotective activities. Importantly, there are two main species of the Euterpe genus which produce acai. There are several differences between them but they are still quite unknown, from literature to producers and consumers. In this review are highlighted the chemical composition, botanical aspects, pharmacological, marketing and nutrition of these species based on studies published in the last five years in order to unify the current knowledge and dissimilarities between them.

Development and validation of an UHPLC-LTQ-Orbitrap MS method for non-anthocyanin flavonoids quantification in Euterpe oleracea juice

Euterpe oleracea fruits have gained much attention because of their phenolic constituents that have shown potential health benefits. The aim of this work was to quantify the major non-anthocyanin flavonoids (NAF) in the fruit juice by an accurate method coupling ultra-high pressure liquid chromatography with a linear ion trap-high resolution Orbitrap mass spectrometry system (UHPLC-LTQ-Orbitrap MS). Fruits were processed to juice, and then the juice was lyophilized and defatted. The residue was then extracted in the presence of methanol by sonication. The extraction time was optimized and recovery rates of the extraction were >90%. The extracts were dried and solubilized again in 40% MeOH, which showed the best compromise for MS detection. For the UHPLC quantification, a HSS C18 column (1.8 μm) was used with a gradient elution of methanol and water both with 0.1% formic acid. Total error and accuracy profiles were used as validation criteria. Seven compounds and their isomers were successfully separated, including the major NAF. Calibration in the matrix was found to be more accurate than calibration without matrix. Trueness (<15% relative bias), repeatability, and intermediate precision (<13% RSD), selectivity, response function, linearity, LOD (ranged from 0.04 to 0.81 μg/mL) and LOQ (0.15-5.78 μg/mL) for 12 compounds were evaluated and the quantification method was validated. Its applicability was demonstrated on real samples from different suppliers. Their qualitative and quantitative profiles were similar and some compounds were for the first time quantified. In addition, eriodictyol was identified for the first time in this fruit along with five other flavonoids for which possible structures were proposed.