Fruits

Fruits come in a wide variety of colors, shapes, and flavors. This chapter will cover selected fruits that are known to be healthy and highly nutritious. These fruits were chosen due to their common usage and availability. Since it is not possible to cover all health benefits or essential nutrients and important phytochemicals of the fruit composition, this chapter will focus on the key valuable constituents and their potential health effects.

Comparison of DNA extraction methods for non-marine molluscs: is modified CTAB DNA extraction method more efficient than DNA extraction kits?

Isolation of high molecular weight DNA from gastropod molluscs and its subsequent PCR amplification is considered difficult due to excessive mucopolysaccharides secretion which co-precipitate with DNA and obstruct successful amplification. In an attempt to address this issue, we describe a modified CTAB DNA extraction method that proved to work significantly better with a number of freshwater and terrestrial gastropod taxa. We compared the performance of this method with Qiagen^® DNeasy Blood and Tissue Kit. Reproducibility of amplification was verified using a set of taxon-specific primers, wherein modified CTAB extracted DNA could be replicated at least four out of five times but kit extracted DNA could not be replicated. In addition, sequence quality was significantly better with CTAB extracted DNA. This could be attributed to the removal of polyphenolic compounds by polyvinyl pyrrolidone which is the only difference between conventional and modified CTAB DNA extraction methods for animals. The genomic DNA isolated using modified CTAB protocol was of high quality (A260/280 ≥ 1.80) and could be used for downstream reactions even after long-term storage (more than 2 years).

Bioactivity of food melanoidins is mediated by gut microbiota

Melanoidins are an important component of the human diet (average consumption 10 g/day), which escape gastrointestinal digestion and are fermented by the gut microbiota. In this study melanoidins from different food sources (coffee, bread, beer, balsamic vinegar, sweet wine, biscuit, chocolate, and breakfast cereals) were submitted to an in vitro digestion and fermentation process, and their bioactivity was assessed. Some melanoidins were extensively used by gut microbes, increasing production of short chain fatty acids (mainly acetate and lactate) and favoring growth of the beneficial genera Bifidobacterium (bread crust, pilsner and black beers, chocolate and sweet wine melanoidins) and Faecalibacterium (biscuit melanoidins). Quantification of individual phenolic compounds after in vitro fermentation allowed their identification as microbial metabolites or phenolics released from the melanoidins backbone (specially pyrogallol, 2-(3,4-dihydroxyphenyl)acetic and 3-(3,4-dihydroxyphenyl)propionic acids). Our results also showed that antioxidant capacity of melanoidins is affected by gut microbiota fermentation.

Plasma polyphenols associated with lower high-sensitivity C-reactive protein concentrations: a cross-sectional study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

Experimental studies have reported on the anti-inflammatory properties of polyphenols. However, results from epidemiological investigations have been inconsistent and especially studies using biomarkers for assessment of polyphenol intake have been scant. We aimed to characterise the association between plasma concentrations of thirty-five polyphenol compounds and low-grade systemic inflammation state as measured by high-sensitivity C-reactive protein (hsCRP). A cross-sectional data analysis was performed based on 315 participants in the European Prospective Investigation into Cancer and Nutrition cohort with available measurements of plasma polyphenols and hsCRP. In logistic regression analysis, the OR and 95 % CI of elevated serum hsCRP (>3 mg/l) were calculated within quartiles and per standard deviation higher level of plasma polyphenol concentrations. In a multivariable-adjusted model, the sum of plasma concentrations of all polyphenols measured (per standard deviation) was associated with 29 (95 % CI 50, 1) % lower odds of elevated hsCRP. In the class of flavonoids, daidzein was inversely associated with elevated hsCRP (OR 0·66, 95 % CI 0·46, 0·96). Among phenolic acids, statistically significant associations were observed for 3,5-dihydroxyphenylpropionic acid (OR 0·58, 95 % CI 0·39, 0·86), 3,4-dihydroxyphenylpropionic acid (OR 0·63, 95 % CI 0·46, 0·87), ferulic acid (OR 0·65, 95 % CI 0·44, 0·96) and caffeic acid (OR 0·69, 95 % CI 0·51, 0·93). The odds of elevated hsCRP were significantly reduced for hydroxytyrosol (OR 0·67, 95 % CI 0·48, 0·93). The present study showed that polyphenol biomarkers are associated with lower odds of elevated hsCRP. Whether diet rich in bioactive polyphenol compounds could be an effective strategy to prevent or modulate deleterious health effects of inflammation should be addressed by further well-powered longitudinal studies.

Antioxidant and antibacterial activity of Trametes polyzona (Pers.) Justo

Polypores are cosmopolitan mushrooms, widely investigated for their beneficial properties in combatting multidrug resistant pathogens. The present study focuses on the need for new, naturally sourced antimicrobial and antioxidant compounds from mushrooms. The antioxidant and antibacterial activity of the phenolic extract of strains of Trametes polyzona (Pers.) Justo, were investigated. Strains of T. polyzona were analyzed for total phenolic content, Trolox antioxidant equivalent, DPPH radical scavenging and antibacterial activities. The amplification of the ribosomal DNA-ITS fragments from DNA of selected mushrooms was carried out using ITS1 and ITS4 primers. The antibacterial activity of phenolic extracts of T. polyzona was comparable to the antibiotics, ceftazidime and erythromycin. T. polyzona extracts inhibited the growth of the different strains of K. pneumoniae, E. coli, S. aureus, and S. enterica tested in this study. The results of the study demonstrate that, T. polyzona can be a potential source of antimicrobial and antioxidant compounds.

Phenolic Acid Subclasses, Individual Compounds, and Breast Cancer Risk in a Mediterranean Cohort: The SUN Project

BACKGROUND

Biological and epidemiological evidence supports an inverse association of phenolic acids with obesity-related chronic diseases. However, no previous study has prospectively evaluated the relationship between subclasses and individual compounds of phenolic acids and the risk of postmenopausal breast cancer, one of the most important and prevalent obesity-related cancer sites.

OBJECTIVE

This study examined associations between subclasses of phenolic acids, including hydroxycinnamic and hydroxybenzoic acids intake, and risk of breast cancer.

DESIGN

The Seguimiento Universidad de Navarra (SUN) Project is a dynamic, permanently open prospective cohort which started in 1999.

PARTICIPANTS/SETTING

Participants were 10,812 middle-aged women. All of them were university graduates.

MAIN OUTCOME MEASURES

Usual diet was assessed at baseline and after 10 years of follow-up with a 136-item food frequency questionnaire. Phenolic acid intake was calculated by matching food consumption with the Phenol-Explorer database on phenolic acids content of each reported food item.

STATISTICAL ANALYSIS PERFORMED

Participants were classified according to tertiles of subclasses or individual compounds of phenolic acids. Cox regression models were fitted to estimate multivariable-adjusted hazard ratios and 95% CIs for breast cancer incidence.

RESULTS

Over an average of 11.8 years of follow-up, 101 incident cases of breast cancer were confirmed. After multivariable adjustment, an inverse association between hydroxycinnamic acids intake and breast cancer was observed (hazard ratio third tertile vs first tertile 0.37, 95% CI 0.16 to 0.85; P for trend=0.029) among postmenopausal women. Specifically, chlorogenic acids (3-, 4-, and 5- caffeoylquinic acids) showed the strongest inverse association (hazard ratio third tertile vs first tertile 0.33, 95% CI 0.14 to 0.78; P for trend=0.012).

CONCLUSIONS

A higher intake of hydroxycinnamic acids, especially from chlorogenic acids-present in coffee, fruits, and vegetables-was associated with a lower incidence of breast cancer among postmenopausal women. Future observational studies are needed to corroborate these results.

Simultaneous quantification of thirty polyphenols in blackthorn flowers and dry extracts prepared thereof: HPLC-PDA method development and validation for quality control

The paper presents development and validation of a RP-HPLC-PDA method for quantification of 30 phenolic constituents of the blackthorn (Prunus spinosa L.) flower, a traditional European herbal medicine with a unique and complex composition. The target analytes were selected from over 50 active compounds present in the investigated plant material, and their separation was optimized on a C18 Ascentis Express fused-core column (2.7 μm, 150 mm × 4.6 mm), in a step-by-step process, in terms of elution solvents, gradient profile, temperature, and flow rate. The final procedure was carried out with an acetonitrile-tetrahydrofuran gradient at a flow rate of 1.09 mL/min and column temperature of 28°C. Under those conditions, the matrix peaks were satisfactorily separated within 35 min. The validation showed good precision (RSD < 5 %), accuracy (93.5-102.1 %), linearity (r > 0.9998), and sensitivity (LODs 0.51-2.05 ng) of the method. The real sample analysis demonstrated its applicability for quantification of the phenolics both in commercial samples of P. spinosa flowers (different manufacturers and years of collection), as well as in the extracts (of different polarity) prepared thereof. Thus, the developed procedure proved to be a useful tool in quality control, and the optimization approach might serve as a practical guideline for LC-method development in complex matrices.

Total polyphenol content and metals determination in Spanish virgin olive oils by means of a dispersive liquid-liquid aerosol phase extraction method and ICP-MS

This report presents a study on the determination of total polyphenols together with metals in several samples of olive oil produced in Spain. The results provided by applying a conventional extraction method were compared against those encountered by means of the so-called Dispersive Liquid-Liquid Aerosol Phase Extraction method. The novel method is based on the dispersion of the extracting solution in the sample. To accomplish this, an aerosol is pneumatically generated and directed against the surface of the oil sample. The aerosol was generated in order to increase as much as possible the surface area of the interface between the two involved non-miscible phases. As a result, the partition equilibrium was quickly achieved. The critical variables dictating the characteristics of the obtained aerosols as well as those influencing the partition equilibrium state were studied. With the aerosol phase extraction method, the values corresponding to the total polyphenols and metals in real samples were not statistically different as compared to those obtained by the conventional liquid - liquid extraction method. The new method provided shorter extraction times and lower mass of consumed reagents than the conventional one, thus giving rise to a more environmentally friendly method. For polyphenols, calculated limits of detection and quantification were 0.48 and 1.5 mg of gallic acid kg^-1, respectively. The absorbance linearity, in turn, was kept from 0 to 50 mg kg^-1 (R² = 0.998). In the case of metal and metalloid quantification, the limits of detection found with a sample digestion method ranged from 1.3 (Cu) to 291 (Na) ng mL^-1. Meanwhile, because of the lower dilution factor, this parameter was one order of magnitude lower when these elements were extracted according to the new method. The new extraction method was applied to the analysis of 42 extra virgin olive oils both bottled and directly collected from the oil press, containing single cultivars or blends and produced from different areas. Fresh oils were analyzed and a preliminary study on the oil thermal degradation was also done. Dispersing the extracting solution as an aerosol into the sample can be considered a versatile method able to provide extensive oil chemical information in a rapid way what is especially important in the case of polyphenols.

Holly polyphenols alleviate intestinal inflammation and alter microbiota composition in lipopolysaccharide-challenged pigs

The effect of holly polyphenols (HP) on intestinal inflammation and microbiota composition was evaluated in a piglet model of lipopolysaccharide (LPS)-induced intestinal injury. A total of twenty-four piglets were used in a 2 × 2 factorial design including diet type and LPS challenge. After 16 d of feeding with a basal diet supplemented with or without 250 mg/kg HP, pigs were challenged with LPS (100 μg/kg body weight) or an equal volume of saline for 4 h, followed by analysis of disaccharidase activities, gene expression levels of several representative tight junction proteins and inflammatory mediators, the SCFA concentrations and microbiota composition in intestinal contents as well as proinflammatory cytokine levels in plasma. Our results indicated that HP enhanced intestinal disaccharidase activities and reduced plasma proinflammatory cytokines including TNF-α and IL-6 in LPS-challenged piglets. Moreover, HP up-regulated mRNA expression of intestinal tight junction proteins such as claudin-1 and occludin. In addition, bacterial 16S rRNA gene sequencing showed that HP altered hindgut microbiota composition by enriching Prevotella and enhancing SCFA production following LPS challenge. These results collectively suggest that HP is capable of alleviating LPS-triggered intestinal injury by improving intestinal disaccharidase activities, barrier function and SCFA production, while reducing intestinal inflammation.

Synthesis and SARs of dopamine derivatives as potential inhibitors of influenza virus PAN endonuclease

Currently, influenza PA_N endonuclease has become an attractive target for development of new drugs to treat influenza infections. Herein we report the discovery of new PA_N endonuclease inhibitors derived from a chelating agent dopamine moiety. A series of dopamine amide derivatives and their conformationally constrained 1,2,3,4-tetrahydroisoquinoline-6,7-diol-based analogs were elaborated and assayed against influenza virus A/WSN/33 (H1N1). Most compounds exhibited moderate to excellent antiviral activities, generating a preliminary SARs. Among them, compounds 14 and 19 showed stronger anti-IAV activity compared with the reference Peramivir. Moreover, 14 and 19 demonstrated a concentration-dependent inhibition of PA_N endonuclease based on both FRET assay and SPR assay. Docking studies were also performed to elucidate the binding mode of 14 and 19 with the PA_N protein and to identify amino acids involved in their mechanism of action, which were well consistent with the biological data. This finding was beneficial to laying the foundation for the rational development of more effective PA_N endonuclease inhibitors.

Polyphenols and inhibitory effects of crude and purified extracts from tomato varieties on the formation of advanced glycation end products and the activity of angiotensin-converting and acetylcholinesterase enzymes

The study analyzed the inhibitory effects (IC50) of crude and purified extracts from Maliniak, Cerise, Black Prince and Lima tomatoes on the formation of advanced glycation end products (AGEs), the activity of angiotensin-converting (ACE) and acetylcholinesterase (AChE) enzymes. Polyphenol composition (LC-MS) and antioxidant capacity (PCL, FRAP) were measured. The purified extracts of Black Prince tomatoes were the most potent inhibitors of AGEs in BSA-GLU (7.20mg/mL) and BSA-MGO (9.53mg/mL) models. The purified extracts of Cerise and Black Prince tomatoes had the highest ACE (0.50-0.44mg/mL) and AChE (7.93-5.83mg/mL) inhibitory activity. Cerise variety showed the highest polyphenol concentrations in crude (488.93μg/g DM) and purified (8394.99μg/g DM) extracts. The highest PCLACW and FRAP values were found for Cerise purified extracts (71.83 and 87.78μmol Trolox/g DM). Caffeic acid, caffeoyl-glucose, linocaffein, glucosyl-coumarate, vanillic acid, rutin and TPI values were significantly correlated with BSA-MGO, anti-ACE, anti-AChE and PCLACW parameters.

Melissa officinalis ssp. altissima extracts: A therapeutic approach targeting psoriasis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Melissa officinalis L., commonly known as lemon balm, is one of the most well known edible and medicinal plants of the Lamiaceae family. It is quoted in almost all known medical treatises, from Antiquity up to modern era, such as Corpus Hippocraticum, Dioscorides' De Materia Medica and later on in medieval medical manuscripts and Pharmacopoeias. Actually, it is widely used as herbal medicine for the relief of mild symptoms of mental stress, to aid sleep and for symptomatic treatment of mild gastrointestinal complaints including bloating and flatulence. In Greece, the empirical physicians "vikoyiatroi" recommended the decoction of dry flowers and leaves to treat tracheobronchitis, hysteria, epilepsy, heart arrhythmias, as hypnotic and against skin disorders.

AIM OF THE STUDY

The present study was conducted to investigate the potential beneficial effects in psoriasis in mice of M. officinalis ssp. altissima and to carry out the chemical analysis in order to reveal its main bioactive secondary metabolites.

MATERIALS AND METHODS

Non polar and polar extracts of M. officinalis ssp. altissima aerial parts were prepared by using dichloromethane and methanol, successively; in addition a decoction was made upon oral information by local users in Crete, where the plant was collected. All three preparations were chemically analyzed in order to isolate their main constituents. Chemical structures of all isolated compounds were determined by 1D, 2D-NMR and UV-Vis spectroscopy. Furthermore, the antioxidant potential of extracts and decoction was evaluated through DPPH radical scavenging capability. The in vivo in mice anti-psoriatic efficacy of all preparations was estimated through clinical and histopathological assessment and measurements of TEWL and hydration.

RESULTS

The dichloromethane extract yielded ursolic acid, 2α-hydroxy-ursolic acid, pomolic acid, 3β-stearyloxy-urs-12-ene, oleanolic acid, noropacursane and campesterol; the methanol extract afforded rosmarinic acid and methyl rosmarinate, while from the decoction caffeic acid, 3-(3,4-dihydroxyphenyl)lactic acid and rosmarinic acid were isolated. The psoriasis evaluation, based on PASI score, photodocumentation and histopathological estimation showed that the decoction primarily and the dichloromethane extract secondly could significantly contribute to psoriasis treatment. The decoction seems able to reestablish skin physiology by decreasing dryness and enhancing skin barrier function. Moreover, the decoction showed the best antioxidant activity, while the dichloromethane extract the weakest.

CONCLUSIONS

The triterpene derivatives of the dichloromethane extract are likely to be responsible for its anti-psoriatic activity. The abundant polyphenolic load of the decoction contributes to its high antioxidant activity and the most effective results against psoriasis. The anti-psoriatic activity of the decoction confirmed the traditional use of this plant as antioxidant, wound healing and skin barrier repair agent.

Maize extract rich in ferulic acid and anthocyanins prevents high-fat-induced obesity in mice by modulating SIRT1, AMPK and IL-6 associated metabolic and inflammatory pathways

The aim was to compare the antiobesity efficacy of different concentrations of a phenolic-rich water extract from purple maize pericarp (PPE) in a murine model of obesity for 12 weeks. Forty C57BL/6 mice (n=10/group) were randomized: standard diet (SD), high-fat diet (HFD), HFD+200 mg PPE/kg (200 PPE) and HFD+500 mg PPE/kg (500 PPE). PPE contained mainly ferulic acid, anthocyanins and other phenolics (total phenolics: 448.5 μg/mg dry weight, DW). Body weight (-27.9%), blood glucose (-26.5%) and blood triglycerides (-22.1%) were most attenuated (P<.05) in 500 PPE group compared to HFD group. Also, 500 PPE group had reduced (P<.05) plasma levels of TNF-α, MCP-1, resistin and leptin compared to HFD group. Fatty liver disease scores were highest for HFD (8.4), followed by 200 PPE (6.1), 500 PPE (2.7) and SD (0.4) groups. Relative adipose tissue was lower (P<.05) in 200 PPE (7.6%), 500 PPE (8.0%) and SD (0.8%) compared to HFD (12.1%) group. In 500 PPE group, compared to HFD group, important genes were modulated related to adipogenesis (Mmp3, fold-change [FC]=7.4), inflammation (Nfkb1, FC=-1.8) and glucose metabolism (Slc2a4, FC=23.6) in adipose tissue. In liver, 500 PPE group showed modulation of genes related to gluconeogenesis (Pck1, FC=-2.9), lipogenesis (Fasn, FC=-2.4) and β-oxidation (Cpt1b, FC=3.1). Maize rich in ferulic acid and anthocyanins prevented obesity through the modulation of TLR and AMPK signaling pathways reducing adipogenesis and adipose inflammation, and promoting energy expenditure.

Partitioning of fatty acids into tissues and fluids from reproductive organs of ewes as affected by dietary phenolic extracts

Evaluation of dietary interventions with regard to fertility problems often observed in ruminant livestock is of global interest. Though the effects of polyphenol supplementation in ruminants on digestion and food quality are well described, the impact on reproductive tissues and fluids remains scarcely investigated. These compounds protect dietary unsaturated fatty acids (FA) from oxidation and biohydrogenation and thus saturation. In addition, modification of the expression of genes associated with FA metabolism may occur. Therefore, we characterized for the first time the FA profiles of reproductive tissues and fluids and investigated their potential modification by dietary polyphenols in 22 cyclic ewes. The animals were randomly divided into four groups and fed a basal diet of meadow hay and one of four concentrate types either non-supplemented (control) or supplemented with grape seed extract, Acacia mearnsii bark extract (13 g/kg dry matter (DM) each) or a combination of both (26 g/kg DM). After 10 weeks of feeding, the animals were slaughtered. Samples of reproductive (oviduct, uterus) and metabolically differently active tissues (liver, muscle, adipose) as well as of plasma and fluids from oviduct and uterus were analysed for their FA composition. In addition, the expression of lipid metabolic and antioxidant genes was analysed in all tissues except the adipose tissue. Fatty acid profiles in tissues and fluids as well as gene expression in tissues significantly differed between the different fluids and tissues. In contrast, only a few diet and matrix (fluid or tissue) × diet interactions were observed. Still, the FA profile of the uterus was the only one not at all affected by the diet. The mRNA expression was not affected by the diet for most of the genes investigated, which might in part be explained by the similar plasma polyphenol concentrations found at slaughter. Overall, our findings contribute to an improved understanding of the characteristic FA composition of reproductive tissues and fluids in sheep. In addition, the effect of polyphenols on different tissues, fluids and tissue gene expression has been confirmed as described in other animal species.

Novel insights into prebiotic properties on human health: A review

Dietary prebiotics can be metabolized by different colonic microorganisms and release several classes of metabolites, particularly SCFAs into the intestine lumen, influencing the host physiology. Thus, human microbiota has been the focus of one of the most dynamic research fields of our time and their efforts are directed to understand how prebiotics structures and the microbiota-derived metabolites acts on signaling cell pathways and epigenetic control. Therefore, the aim of this review is to provide an overview about the new concept of prebiotics and their mechanistic local and systemically insights related to the host health.

Therapeutic potential of polyphenols in cardiovascular diseases: Regulation of mTOR signaling pathway

Cardiovascular diseases comprise of non-communicable disorders that involve the heart and/or blood vessels and have become the leading cause of death worldwide with increased prevalence by age. mTOR is a serine/threonine-specific protein kinase which plays a central role in many physiological processes including cardiovascular diseases, and also integrates various proliferative signals, nutrient and energy abundance and stressful situations. mTOR also acts as central regulator during chronic stress, mitochondrial dysfunction and deregulated autophagy which are associated with senescence. Under oxidative stress, mTOR has been reported to exert protective effects regulating apoptosis and autophagy processes and favoring tissue repair. On the other hand, inhibition of mTOR has been suggested to have beneficial effects against atherosclerosis, cardiac hypertrophy and heart failure, and also in extending the lifespan. In this aspect, the use of drugs or natural compounds, which can target mTOR is an interesting approach in order to reduce the number of deaths caused by cardiovascular disease. In the present review, we intend to shed light on the possible effects and molecular mechanism of natural agents like polyphenols via regulating mTOR.

Neuroprotective Polyphenols: A Modulatory Action on Neurotransmitter Pathways

BACKGROUND

Balance in neurotransmission is essential for the proper functioning of the nervous system and even a small, but prolonged disturbance, can induce the negative feedback mechanisms leading to various neuropathologies. Neurodegenerative and mood disorders such as Alzheimer's, Parkinson's or affective disorders are increasing medical and social problems. Among the wide spectrum of potentially destructive events, oxidative stress and disrupted metabolism of some neurotransmitters such as acetylcholine, GABA, glutamate, serotonin or dopamine appear to play a decisive role. Biologically active plant polyphenols have been shown to exert a positive impact on the function of the central nervous system by modulation of metabolism and the action of some neurotransmitters.

METHODS

Based on published research, the pharmacological activities of some naturally occurring polyphenols have been reviewed, with a focus on their potential therapeutic importance in the regulation of neurotransmitter systems.

RESULTS

Phytochemicals can be classified into several groups and most of them possess anticancer, antioxidative, anti-inflammatory and neuroprotective properties. They can also modulate the metabolism or action of some neurotransmitters and/or their receptors. Based on these properties, phytochemicals have been used in traditional medicine for ages, although it was focused mainly on treating symptoms. However, growing evidence indicates that polyphenols may also prevent or slow neurological diseases.

CONCLUSION

Phytochemicals seem to be less toxic than synthetic drugs and they can be a safer alternative for currently used preparations, which exert adverse side effects. The neuroprotective actions of some plant polyphenols in the regulation of neurotransmitters metabolism, functioning of neurotransmitters receptors and antioxidative defense have potential therapeutic applications in various neurodegenerative disorders.

The strange case of polyphenols inhibiting the Briggs-Rauscher reaction: pH-modulated reactivity of the superoxide radical

Superoxide radical is one of the main players when it comes to oxidative stress. Even if in itself is moderately reactive and can cause the degradation of very few biologically relevant macromolecules, it can dismutate to hydrogen peroxide followed by a possible conversion to hydroxyl radical. In order to protect the internal environment against reactive oxygen species, plants have evolved a line of defence made from secondary metabolites with versatile redox properties, such as flavonoids and phenolic acids. Their characteristics are highly modulated by pH, as they turn into prooxidant compounds as it increases. Reported here are the behaviour and clear patterns in reactivity towards superoxide anion radical of four classes of plant phenolics as a pH function. The reactivity towards superoxide radical in acidic conditions has been studied by use of oscillating Briggs-Rauscher reaction with a new spectroelectrochemical experimental setup, by recording the absorbance in high quality for the first time. Some mechanistic intricacies have also been explored with regard to this method. Reactivity modulation at neutral and slightly basic pH has been assayed by superoxide radical scavenging ability using nitroblue tetrazolium as a substrate. For stronger alkaline pHs studies, Electron Paramagnetic Resonance was exploited. Hydroxybenzoic acids tend to be the least reactive species at all tested pH values. Hydroxycinnamic acids have their activity towards superoxide radical decreased as the pH increases, whereas flavonoids act vice versa.

Effect of harvesting year and elderberry cultivar on the chemical composition and potential bioactivity: A three-year study

Sambucus nigra is one of the richest sources of anthocyanins and other polyphenols being used industrially as a source of antioxidants, colorants, and bioactives. Although cultivars can influence elderberry composition, no study has addressed the effect of harvesting year on elderberries composition and bioactivity. The composition of the main Portuguese cultivars, "Sabugueiro", "Sabugueira" and "Bastardeira", were evaluated during three consecutive years. Harvesting year had a stronger influence on the chemical composition than cultivars, including total sugars, anthocyanins, and phenolic compounds, being related to the different climatic conditions, especially water status. "Bastardeira" was the best cultivar concerning total soluble solids, anthocyanins, polyphenols, and antioxidant activity, but containing a lower total free sugar content compared to "Sabugueiro". The results obtained in this study provide novel information from a nutritional perspective and for breeding programs aiming to select cultivars with enhanced levels of health-promoting compounds or for other industrial applications of elderberries.

Olive oil by-product as functional ingredient in bakery products. Influence of processing and evaluation of biological effects

Nowadays, the strong demand for adequate nutrition is accompanied by concern about environmental pollution and there is a considerable emphasis on the recovery and recycling of food by-products and wastes. In this study, we focused on the exploitation of olive pomace as functional ingredient in biscuits and bread. Standard and enriched bakery products were made using different flours and fermentation protocols. After characterization, they were in vitro digested and used for supplementation of intestinal cells (Caco-2), which underwent exogenous inflammation. The enrichment caused a significant increase in the phenolic content in all products, particularly in the sourdough fermented ones. Sourdough fermentation also increased tocol concentration. The increased concentration of bioactive molecules did not reflect the anti-inflammatory effect, which was modulated by the baking procedure. Conventionally fermented bread enriched with 4% pomace and sourdough fermented, not-enriched bread had the greatest anti-inflammatory effect, significantly reducing IL-8 secretion in Caco-2 cells. The cell metabolome was modified only after supplementation with sourdough fermented bread enriched with 4% pomace, probably due to the high concentration of tocopherol that acted synergistically with polyphenols. Our data highlight that changes in chemical composition cannot predict changes in functionality. It is conceivable that matrices (including enrichment) and processing differently modulated bioactive bioaccessibility, and consequently functionality.

Effect of different soluble dietary fibres on the phenolic profile of blackberry puree subjected to in vitro gastrointestinal digestion and large intestine fermentation

The aim of this study was to investigate the modulation of polyphenols profile of blackberry purees by soluble dietary fibres (inulin or pectin), during a simulated in vitro gastrointestinal digestion and large intestine fermentation process. Untargeted profiling evidenced that the free phenolic fraction of blackberry puree was characterized mainly by flavonoids, followed by phenolic acids, lignans and other low molecular weight polyphenols, showing clear differences from the bound phenolic fraction detected. This trend could be related to the interactions of dietary fibre and polyphenols, showing synergistic and/or antagonist effect on the bioactivity of polyphenols. On the other hand, in vitro large intestine fermentation of blackberry purees following in vitro gastrointestinal digestion revealed that the highest inclusion level (10% w/w) of soluble dietary fibres was effective in modulating the bioaccessibility of some phenolic classes (mainly phenolic acids, lignans and flavones) characterizing the blackberry puree. In addition, multivariate statistics following metabolomics-based profiling showed that the interaction between fibres and blackberry purees determined a marked modification of both anthocyanins and flavonols during in vitro large intestine fermentation, thus leading to the formation of low-molecular-weight compounds (such as tyrosol, followed by gallic and benzoic acids).

Immune Th17 lymphocytes play a critical role in the multiple beneficial properties of resveratrol

Modulation of the inflammatory response is one of the major issues of the 21st century due to its importance in the occurrence of various pathologies (cancer, autoimmune diseases, degenerative diseases) and their progression over time. Whether acute or chronic, the inflammatory response is directly related to the immune response through different subtypes of T lymphocytes. In addition, among the compounds capable of modulating the cells of the immune system, resveratrol, a polyphenol with pleiotropic biological properties, seems to be a good candidate. Indeed, resveratrol is able to alter the immune response by modulating the process of lymphocyte differentiation and subsequently diminishing the inflammatory-associated response. More specifically, thanks to its ability to act as a sirtuin-1 agonist, it can deacetylate the transcription factor STAT3 and alter nuclear factors essential to the process of lymphocyte differentiation. We present and discuss these different aspects in relation to various pathologies and how the alteration of the ratios between the different lymphocyte subtypes by resveratrol is an important element to take into account when studying its anti-inflammatory and immunomodulatory properties.

Adherence to UK dietary guidelines is associated with higher dietary intake of total and specific polyphenols compared with a traditional UK diet: further analysis of data from the Cardiovascular risk REduction Study: Supported by an Integrated Dietary Approach (CRESSIDA) randomised controlled trial

Adherence to dietary guidelines (DG) may result in higher intake of polyphenols via increased consumption of fruits, vegetables and whole grains. We compared polyphenol dietary intake and urinary excretion between two intervention groups in the Cardiovascular risk REduction Study: Supported by an Integrated Dietary Approach study: a 12-week parallel-arm, randomised controlled trial (n 161; sixty-four males, ninety-seven females; aged 40-70 years). One group adhered to UK DG, whereas the other group consumed a representative UK diet (control). We estimated polyphenol dietary intake, using a 4-d food diary (4-DFD) and FFQ, and analysed 24-h polyphenol urinary excretion by liquid chromatography-tandem MS on a subset of participants (n 46 control; n 45 DG). A polyphenol food composition database for 4-DFD analysis was generated using Phenol-Explorer and USDA databases. Total polyphenol intake by 4-DFD at endpoint (geometric means with 95 % CI, adjusted for baseline and sex) was significantly higher in the DG group (1279 mg/d per 10 MJ; 1158, 1412) compared with the control group (1084 mg/d per 10 MJ; 980, 1197). The greater total polyphenol intake in the DG group was attributed to higher intake of anthocyanins, proanthocyanidins and hydroxycinnamic acids, with the primary food sources being fruits, cereal products, nuts and seeds. FFQ estimates of flavonoid intake also detected greater intake in DG compared with the control group. 24-h urinary excretion showed consistency with 4-DFD in their ability to discriminate between dietary intervention groups for six out of ten selected, individual polyphenols. In conclusion, following UK DG increased total polyphenol intake by approximately 20 %, but not all polyphenol subclasses corresponded with this finding.

Alpine and lowland grazing differentially alter the reproductive tract redox milieu and amino acid composition in cattle

An alpine environment is unique due to pasture biodiversity, with an abundant content of natural antioxidant polyphenols. The present study investigated the effects of lowland and alpine grazing on the oviduct and uterine tissue redox status and amino acid concentrations in plasma and reproductive fluids. In the first experiment, heifers grazed on lowland (H-LOW: n = 13) and on alpine (H-ALP: n = 15) pastures. In the second experiment, heifers grazed on the same lowland (HS-LOW: n = 6) and on a different alpine (HS-ALP: n = 6) pasture. The abundance of mRNA transcripts for antioxidant enzymes in the oviduct (glutathione S-transferase alpha 2, glutathione synthetase (GSS)) and the endometrium (catalase, glutathione-disulfide reductase, GSS) was less (P <  0.05), and for glutathione peroxidase 4 in the endometrium greater (P =  0.006) in the H-LOW than in the H-ALP group. The abundance of mRNA transcript for catalase was less in the endometrium in the H-LOW than in the H-ALP (P =  0.001) group. Catalase and NAD(P)H quinone dehydrogenase 1 concentrations in the oviduct were greater in the HS-LOW than in the HS-ALP group (P <  0.05). Of 32 amino acids analysed, there were differences in concentrations in the H-LOW and H-ALP group of 13, seven and 15 in plasma, oviduct and uterine fluids, respectively (P <  0.05). Comparing the HS-LOW to the HS-ALP groups, there were 13, one and three amino acids in the plasma, oviduct and uterine fluids, respectively, that were differentially abundant (P <  0.05). The grazing systems had some effect on the redox status and amino acid patterns in reproductive tissues.

Natural products targeting the PI3K-Akt-mTOR signaling pathway in cancer: A novel therapeutic strategy

The phosphatidylinositol 3-kinase (PI3K)-Akt and the mammalian target of rapamycin (mTOR) represent two vital intracellular signaling pathways, which are associated with various aspects of cellular functions. These functions play vital roles in quiescence, survival, and growth in normal physiological circumstances as well as in various pathological disorders, including cancer. These two pathways are so intimately connected to each other that in some instances these are considered as one unique pathway crucial for cell cycle regulation. The purpose of this review is to emphasize the role of PI3K-Akt-mTOR signaling pathway in different cancer conditions and the importance of natural products targeting the PI3K-Akt-mTOR signaling pathway. This review also aims to draw the attention of scientists and researchers to the assorted beneficial effects of the numerous classes of natural products for the development of new and safe drugs for possible cancer therapy. We also summarize and critically analyze various preclinical and clinical studies on bioactive compounds and constituents, which are derived from natural products, to target the PI3K-Akt-mTOR signaling pathway for cancer prevention and intervention.