Almond, as a part of the nut family, is an important source of biological compounds, and specifically, almond skins have been considered an important source of polyphenols, including flavan-3-ols and ...flavonols. Polyphenol metabolism may produce several classes of metabolites that could often be more biologically active than their dietary precursor and could also become a robust new biomarker of almond polyphenol intake. In order to study urinary metabolome modifications during the 24 h after a single dose of almond skin extract, 24 volunteers (n = 24), who followed a polyphenol-free diet for 48 h before and during the study, ingested a dietary supplement of almond skin phenolic compounds (n = 12) or a placebo (n = 12). Urine samples were collected before ((−2)−0 h) and after (0−2 h, 2−6 h, 6−10 h, and 10−24 h) the intake and were analyzed by liquid chromatography−mass spectrometry (LC-q-TOF) and multivariate statistical analysis (principal component analysis (PCA) and orthogonal projection to latent structures (OPLS)). Putative identification of relevant biomarkers revealed a total of 34 metabolites associated with the single dose of almond extract, including host and, in particular, microbiota metabolites. As far as we know, this is the first time that conjugates of hydroxyphenylvaleric, hydroxyphenylpropionic, and hydroxyphenylacetic acids have been identified in human samples after the consumption of flavan-3-ols through a metabolomic approach. The results showed that this non-targeted approach could provide new intake biomarkers, contributing to the development of the food metabolome as an important part of the human urinary metabolome.
Phenolic compounds are partly responsible for the color, astringency, and bitterness of wine, as well as for numerous physiological properties associated with wine consumption. Mass spectrometry has ...allowed for great progress in the identification and characterization of wine polyphenols. The aim of the present article is to summarize the numerous advances recently achieved in this field. The main type of phenolic compounds found in wine, including hydroxybenzoic and hydroxycinnamic acids, stilbenes, flavones, flavonols, flavanonols, flavanols, and anthocyanins, are firstly described. Chemical reactions and mechanisms involving phenolic compounds during winemaking are also extensively discussed, including enzymatic and chemical oxidation reactions, direct and acetaldehyde-mediated anthocyanin-tannin condensation reactions, acetaldehyde-mediated and glyoxylic acid-mediated tannin-tannin condensation reactions and, C-4/C-5 anthocyanin cycloaddition reactions with 4-vinylphenols, vinylflavanols and pyruvic acid, among others, leading to the formation of pyranoanthocyanins. Useful mass spectral data of well-known and novel phenolic compounds recently identified in wine, and details related to their fragmentation pathway according to different ionization techniques, are given.
Socio-environmental policy issues are characterized by inherent scientific uncertainty, ignorance and frequently by social discrepancies. Lack of recognition of the complexity and uncertainty of ...environmental issues has given rise to problems that have cast doubt on the adequacy of the science for policy model and traditionally employed evidence-based policy, thus leading to a crisis in science. In this context, there is a need for quality assurance procedures to assess policies and measures resulting from decision-making in environmental governance issues.
Involving quality assurance in decision-making processes recognizes the different types of uncertainty related to an issue and the limits of problem-solving analysis. This approach requires participatory methodological frameworks in which stakeholders analyze the robustness of the assessment process used as well as the validity of assessment results. The approach considers governance as being a relative term depending on the historical, social, economic, political, environmental and cultural context in which it is developed.
A participatory methodology is applied to an assessment of forest track alternatives on the island of Tenerife (Canary Islands). In this study, a social sensitivity analysis explores the social validity of this assessment through the concept of quality understood as ‘fitness for use’. Such a methodology facilitates processes of dialogue and consensus needed in decision-making in conflictive situations. As a result this methodology should serve as a reference for other places with similar situations.
The aim of the present work was to develop a reproducible, sensitive, and rapid UPLC-ESI-TQ MS analytical method for determination of microbial phenolic acids and other related compounds in faeces. A ...total of 47 phenolic compounds including hydroxyphenylpropionic, hydroxyphenylacetic, hydroxycinnamic, hydroxybenzoic, and hydroxymandelic acids and simple phenols were considered. To prepare an optimum pool standard solution, analytes were classified in 5 different groups with different starting concentrations according to their MS response. The developed UPLC method allowed a high resolution of the pool standard solution within an 18 min injection run time. The LOD of phenolic compounds ranged from 0.001 to 0.107 μg/mL and LOQ from 0.003 to 0.233 μg/mL. The method precision met acceptance criteria (<15% RSD) for all analytes, and accuracy was >80%. The method was applied to faecal samples collected before and after the intake of a flavan-3-ol supplement by a healthy volunteer. Both external and internal calibration methods were considered for quantification purposes, using 4-hydroxybenzoic-2,3,4,5-d 4 acid as internal standard. For most analytes and samples, the level of microbial phenolic acids did not differ by using one or another calibration method. The results revealed an increase in protocatechuic, syringic, benzoic, p-coumaric, phenylpropionic, 3-hydroxyphenylacetic, and 3-hydroxyphenylpropionic acids, although differences due to the intake were only significant for the latter compound. In conclusion, the UPLC-DAD-ESI-TQ MS method developed is suitable for targeted analysis of microbial-derived phenolic metabolites in faecal samples from human intervention or in vitro fermentation studies, which requires high sensitivity and throughput.
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•Quantitative analytical procedures for the direct analysis of intact glucosinolates in maca were developed for the first time.•The complete glucosinolate profiles (composition and ...contents) of three mace root powder products were established.•Sample analysis revealed a correlation of glucotropaeolin : glucolimnanthin (1 : 0.19) across all products with a correlation coefficient of 0.994.•The stability and degradation pathways of glucosinolates in maca root powder products under non-enzymatic conditions were revealed.•The developed procedures were validated and applied to a total of 42 samples from 11 manufacturers.
The demand and sales of dietary supplements derived from maca (Lepidium meyenii) have skyrocketed in the last decade and a variety of related nutritional and healthcare products have mushroomed into a business with market prominence. However, the lack of standard testing protocols for quality control could jeopardize the immediate benefits of these products for public health. We describe herein the development of analytical procedures for the determination of glucosinolates (GLs), the biologically active ingredients in maca. Because of the high polarity and instability caused by enzymatic hydrolysis, GLs in maca have been exclusively analyzed using desulfated GLs. This indirect analysis requires additional sample preparation steps, which is labor-intensive, and may lose the original GLs and introduce artificial compounds. Furthermore, the reported GL profiles of maca are inconsistent and incomplete, some GLs may be structurally misidentified. In this context, we focused on direct analysis of intact GLs in maca without the enzymatic desulfation. Four GLs (sinalbin, glucolepigramin, glucolimnanthin, and glucotropaeolin) were identified as the major GLs in maca root powder. An HPLC method based on ion pair chromatography was developed to determine individual and total GLs; chromatographic separations were achieved on a Luna column (C18, 4.6 × 100 mm,3 mm) using 0.1 % TFA in water and in methanol as mobile phase in a gradient elution mode. The developed procedures were validated within the calibration range of 10–500 μg/mL. Inter- and intra-day precision were shown to be lower than 3% at all concentrations levels with recovery between 100.2 % and 103.3 %. The procedures were applied to a total of 42 maca root powder products from 11 manufacturers. Sample analysis revealed a consistent correlation of glucotropaeolin: glucolimnanthin (1: 0.19) across all products with a correlation coefficient of 0.994. The correlation in combination with total GL contents for each product could be used for authentication and GL content determination. Incorporation of the developed procedures into USP monographs will strengthen the public standards for maca powder dietary supplements.
The phenolic composition of extracts from Uncaria tomentosa L. from different regions of Costa Rica was studied using advanced analytical techniques such as UPLC/TQ-ESI-MS and (13)C-NMR. Samples from ...leaves, stems, bark and wood (n = 22) were subjected to extraction to obtain phenolic and alkaloid extracts, separately. Comparatively, higher values of total phenolic content were observed for leaves, stems and bark (225-494 gallic acid equivalents/g) than for wood extracts (40-167 gallic acid equivalents/g). A total of 32 non-flavonoid and flavonoid compounds were identified in the phenolic extracts: hydroxybenzoic acids (benzoic, salicylic, 4-hydroxybenzoic, prochatechuic, gallic, syringic and vanillic acids), hydroxycinnamic acids (p-coumaric, caffeic, ferulic and isoferulic acids), flavan-3-ols monomers (+)-catechin and (-)-epicatechin), procyanidin dimers (B1, B2, B3, B4, B5, B7 and two other of unknown structure) and trimers (C1, T2 and one of unknown structure), flavalignans (four unknown structures pertaining to the cinchonain family) and propelargonidin dimers (four unknown structures, reported for the first time in U. tomentosa). Additionally, alkaloid extracts obtained from the plant residue after phenolic extraction exhibited a content of tetracyclic and pentacyclic alkaloids ranging between 95 and 275 mg/100 g of dry material for bark extracts, and between 30 and 704 mg/100 g for leaves extracts. In addition, a minor alkaloid was isolated and characterized, namely 18,19-dehydrocorynoxinoic acid. Our results confirmed the feasibility of U. tomentosa as a suitable raw material for obtaining phenolic- and alkaloid-rich extracts of potential interest.
Epidemiological studies have demonstrated the beneficial effect of plant-derived food intake in reducing the risk of cardiovascular disease (CVD). The potential bioactivity of cocoa and its ...polyphenolic components in modulating cardiovascular health is now being studied worldwide and continues to grow at a rapid pace. In fact, the high polyphenol content of cocoa is of particular interest from the nutritional and pharmacological viewpoints. Cocoa polyphenols are shown to possess a range of cardiovascular-protective properties, and can play a meaningful role through modulating different inflammatory markers involved in atherosclerosis. Accumulated evidence on related anti-inflammatory effects of cocoa polyphenols is summarized in the present review.
Agriculture is the main driving force of rural economies so there is a need to promote sustainable rural development and hence improve the living conditions of local communities. This article ...analyses the role of agricultural policies in reducing poverty in rural communities. Two aspects will be analysed: firstly, whether there has been a reduction in poverty in the basins analysed for the period 2006–2013; and secondly, whether that poverty reduction, to the extent that it has occurred, has been due to the agricultural policies applied. The analysis shows that the agricultural policies implemented helped to diversify and enhance agricultural production, so that a reduction in effective poverty occurred. However, these policies need to work jointly and in harmony with other economic sectors.
The biological properties of cocoa (
Theobroma cacao L.) polyphenols are strictly dependent on their bioavailability. A long-term cocoa feeding trial was performed with subjects at high risk for ...cardiovascular disease. Subjects (
n
=
42) received two sachets of 20
g of cocoa powder/day with 250
mL of skimmed milk each, or only 500
mL/day of skimmed milk, both for two 4-week periods. The phenolic metabolic profile including phase II conjugated metabolites and phenolic acids derived from the intestinal microbiota was determined by LC-MS/MS in both 24-h urine and fasting plasma. The analysis of 24-h urine revealed significant increases of phase II metabolites, including glucuronides and sulfate conjugates of (−)-epicatechin,
O-methyl-epicatechin, 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone and 5-(3′-methoxy-4′-hydroxyphenyl)-γ-valerolactone, after regular cocoa intake. In the case of plasma, only glucuronide conjugates of dihydroxyphenylvalerolactones increased. Regular consumption of cocoa also resulted in a significant increase in the urinary excretion of colonic microbial-derived phenolic metabolites, including vanillic, 3,4-dihydroxyphenylacetic and 3-hydroxyphenylacetic acids, and particularly 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone, whereas only the two latter metabolites showed a significant increase in fasting plasma. The results found herein indicate that 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone and hydroxyphenylacetic acids could be good biomarkers of the regular consumption of cocoa and therefore, of flavanol-rich foods.
Food polyphenols are able to selectively modify the growth of susceptible micro-organisms. This study describes the effect of a flavan-3-ol enriched grape seed extract (GSE) on the growth of several ...lactic acid bacteria (LAB) and bifidobacteria and the ability of the resistant strains to metabolize these compounds. Streptococcus thermophilus, Lactobacillus fermentum, Lactobacillus acidophilus and Lactobacillus vaginalis strains showed a remarkable sensitivity to the phenolic extracts assayed, including a GSE fraction consisting mainly in (+)-catechin and (−)-epicatechin (GSE-M). On the other hand, Lactobacillus plantarum, Lactobacillus casei, and Lactobacillus bulgaricus strains reached maximal growth with the GSE fractions, including a rich-oligomeric (GSE-O) fraction. Within bifidobacteria, Bifidobacterium lactis BB12 showed the highest sensitivity to the phenolic extracts assayed, whereas Bifidobacterium breve 26M2 and Bifidobacterium bifidum HDD541 reached maximum growth in presence of GSE-O and GSE-M fractions. Metabolism of flavan-3-ols by LAB and bifidobacteria resistant strains was investigated in vitro. The results revealed that only L. plantarum IFPL935 was able to metabolize the polyphenols studied by means of galloyl-esterase, decarboxylase and benzyl alcohol dehydrogenase activities that led to the formation of gallic acid, pyrogallol and catechol, respectively. An unknown metabolite that does not exhibit a phenolic-acid-type structure was also detected, which suggests a new enzyme activity in L. plantarum IFPL935 able to degrade flavan-3-ol monomers.
► Flavan-3-ols are inhibitory of lactic acid bacteria and bifidobacteria growth depending on the concentration and composition. ► Resistance of L. plantarum to flavan-3-ols is related to bacteria metabolism. ► L. plantarum IFPL935 is able to metabolize galloylated procyanidins in a complex extract. ► L. plantarum IFPL935 possess a new enzyme activity which degrades flavan-3-ol monomers to non-phenolic-acid-type compounds.
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