Phoenix dactylifera L. seeds: a by-product as a source of bioactive compounds with antioxidant and enzyme inhibitory properties

Date (Phoenix dactylifera L.) seeds are a valuable and abundant by-product with various potential food applications and a source of functional and bioactive ingredients. In this study, date seeds from eight cultivars (Ourous “OUR”, Tazizaout “TAZ”, Tazarzeit “TAR”, Tazoughart “TAG”, Ouaouchet “OUC”, Oukasaba “OUK”, Delat “DEL” and Tamezwertn'telet “TWT”) cultivated in the M'zab oasis (south of Algeria) were analyzed for their chemical and phytochemical compositions, antioxidant capacities and in vitro inhibition of some enzymes. Variations in chemical compositions were observed in the studied date seeds. The greatest contents of total phenolic compounds (476 mg GAE per g dw), total flavonoids (6.52 mg QE per g dw), anthocyanins (1.26 mg Q3GE per g dw), flavonols (3.36 mg Q3GE per g dw), proanthocyanidins (85.13 mg CE per g dw), and ascorbic acid were detected in the seeds of the TAG cultivar. All extracts manifested good antioxidant activities tested by ORAC and FRAP assays. The OUC and OUR extracts displayed the most potent antioxidant capacity against DPPH˙ free radicals (IC50 = 37.30 μg ml−1) and ABTS˙+ cation radicals (IC50 = 13.89 μg ml−1), respectively. The antioxidant activity evaluated through a xanthine/xanthine oxidase system demonstrated that the TAZ extract was more efficient as a superoxide radical scavenger (IC50 = 9.08 μg ml−1). Date seed extracts (DSE) exhibited inhibitory activities on enzymes, showing substantial potential as skin-whitening, neuroprotective, anti-hyperglycemic or anti-hyperlipidemic agents; the inhibitory potential was tested using tyrosinase (TYR), acetylcholinesterase (AChE), α-glucosidase (α-GLU) and lipase. All date seed cultivars were able to inhibit tyrosinase and α-glucosidase in a dose-dependent manner reaching the maximum inhibition

Effect of Grape Pomace Polyphenols With or Without Pectin on TMAO Serum Levels Assessed by LC/MS-Based Assay: A Preliminary Clinical Study on Overweight/Obese Subjects

Growing evidence suggests that trimethylamine N-oxide (TMAO) is recognized as a biomarker of increased cardiovascular risk. So far, the evaluation of TMAO serum levels in the clinical practice is limited due to the lack of developing new facile methods with reduced limitations. However, few approaches were achieved to determine TMAO in serum by using mass spectrometry-based technique, some limitations were reported including the use of internal standards. Therefore, in this work, a liquid chromatography-mass spectrometry (LC/MS) based-assay was developed to evaluate the effect of grape pomace extract (Taurisolo®, group A) or Taurisolo®+pectin (group B) on TMAO serum levels in a cohort of overweight/obese subjects. The serum levels of TMAO have been assessed before and after treatment, through LC/MS analysis. After 8-week treatment, in both intervention groups TMAO serum levels significantly decreased (-78.58% p = 0.006 and -76.76% p = 0.001, group A and group B, respectively). Moreover, we performed several analyses aimed to validate the LC/MS method we used. The method has high precision (% C.V = from 12.12 to 3.92% and from 8.25 to 1.07% for intraday and interday, respectively) and accuracy (% bias = from -5.52 to 0.5% and from -1.42 to 3.08% for intraday and interday, respectively). TMAO recoveries from serum ranged from 99 to 97%; LOD: 2 ng/ml and LOQ: 6 ng/ml. In conclusion, we demonstrated the efficacy of a novel nutraceutical formulation in reducing TMAO serum levels in high cardiovascular risk-subjects, and proposed a useful, versatile and rapid LC/MS method for identification and quantization of TMAO, without the use of marked/isotopic internal standards. It, thus, may represent a novel and practical method with applications in clinical practice and nutraceutical research.Clinical Trial Registration: This study is listed on the ISRCTN registry with ID ISRCTN10794277 (doi: 10.1186/ISRCTN10794277)

Research and development of nutraceuticals useful for metabolic syndrome and inflammatory diseases.

Metabolic syndrome (MetS) represents a cluster of metabolic abnormalities that include hypertension, central obesity, insulin resistance, and atherogenic dyslipidaemia, and is strongly associated with an increased risk for developing diabetes and atherosclerotic and nonatherosclerotic cardiovascular disease (CVD). The pathogenesis of MetS involves both genetic and acquired factors that contribute to the final pathway of inflammation that leads to CVD. MetS has gained significant importance recently due to the exponential increase in obesity worldwide. Early diagnosis is important in order to employ lifestyle and risk factor modification, and the research of novel natural remedies for prevention and treatment of MetS is the basis of reduction of standard therapy side effects. In the present thesis, I focused the attention on omega-3 and omega-6 fatty acids, milk-derived peptides and abscisic acid, three compounds potentially involved in the regulation of plasma triglycerides, intestinal permeability and glycaemia. Three nutraceutical sources have been considered, Salvia hispanica L., Buffalo Mozzarella cheese and peschiole, as a novel complementary and/or alternative safe remedy with clinical relevance in the MetS prevention. The first aim was to test a chia seed-based nutraceutical formulation (CSN) for its potential effects on plasma triglyceride levels of healthy subjects with moderate dyslipidaemia. A cohort of 52 individuals were administered daily, for 8 weeks, with four gastro-resistant capsules of CSN, each one containing 500 mg of cryo-micronized chia seeds and 15 mg of vitamin E, according to a single centre, randomised, placebo controlled, 16 weeks trial. Data showed the following mean lipid changes: triglycerides, −27.5% (P = .0095); total cholesterol, −8.0% (P = .0019); High Density Lipoprotein cholesterol, +5.7% (P = .0042); Low Density Lipoprotein cholesterol, −10.2% (P = .0021). Secondly, the bioactive properties of milk and milk-products are largely attributed to the peptides released during gastrointestinal digestion. Nevertheless, no similar studies on “Mozzarella di Bufala Campana DOP” (MBC), the European name given to a unique protected origin designation buffalo milk product, are available so far. A novel antioxidant peptide (MBCP) after MBC gastrointestinal digestion was identified and its in vitro intestinal protection, bioavailability, and anti-haemolytic capacity were assayed. A 0.2 mg/ml MBCP incubation dose made H2O2-stressed CaCo2 cell line proliferation increase by about 100%. Less than 10% hydrolysis in the apical solution and about 10% concentration in the basolateral solution indicated for MBCP good stability and bioavailability, respectively. A 0.2 mg/ml MBCP incubation dose reduced H2O2-induced human erythrocyte haemolysis by 91.25%. The next step was to evaluate the therapeutic potential of MBCP in inflammatory bowel disease (IBD). I studied the effect of MBCP on (i) inflamed human intestinal Caco2 cells, (ii) dinitrobenzene sulfonic acid (DNBS) mice model of colitis and (iii) the administration in a clinical trial of a nutraceutical formulation corresponding quali-quantitative to MBCP composition. I have shown that MBCP, at non-cytotoxic concentrations, both in vitro and in vivo induced the adherens epithelial junctions organization, modulated the nuclear factor (NF)-κB pathway and reduced the intestinal permeability. Furthermore, the clinical trial showed, after 8 weeks of treatment, a reduction of lactulose/mannitol ratio, an index on intestinal permeability, of -75.2% (P < .01). The results obtained underline that MBCP possesses anti-inflammatory effects both in vitro and in vivo, and it is confirmed by a randomised, placebo controlled, study. Lastly, I tested the effect of a peschiole-based novel nutraceutical formulation, rich in abscisic acid, on the metabolic parameters that are dysregulated in prediabetes and MetS. A cohort of 20 patients were administered daily, for 12 weeks, with two sachets for meal (breakfast, lunch, and dinner) corresponding to 30 μg abscisic acid. Data showed the following metabolic parameters mean: glycaemia, -26,85% *; insulin, -33,63% *; HOMA-IR, -58,89% *; glycated haemoglobin (HbA1c), -20,18% * (*P < .01). Thus, CSN showed a clinical relevance in the primary cardiovascular disease prevention, MBCP helps to restore the intestinal epithelium integrity damaged by inflammation, and peschiole-based novel nutraceutical formulation may control plasma glycaemia, collaborating in the development of nutraceuticals useful for the treatment and prevention of MetS

A Sustainable Extraction Approach of Phytochemicals from Date (<i>Phoenix dactylifera</i> L.) Fruit Cultivars Using Ultrasound-Assisted Deep Eutectic Solvent: A Comprehensive Study on Bioactivity and Phenolic Variability

The present study aimed to evaluate the efficacy of natural deep eutectic solvents (NADESs) on the extraction of phytochemicals from eight Algerian date fruit cultivars (Phoenix dactylifera L.). In this study, lactic acid/sucrose-based NADESs were used as an alternative to conventional chemical solvents using the ultrasound-assisted extraction (UAE) method. The obtained extracts were assessed for the determination of bioactive compound contents, phenolic composition, antioxidant activity, and enzyme inhibitory potential. The results showed a considerable variation in phytochemical compositions and related activities between cultivars, where the greatest contents of total phenolics (1288.7 mg GAE/100 g), total flavonoids (53.8 mg QE/100 g), proanthocyanidins (179.5 mg CE/g), and total triterpenoids (12.88 mg OAE/100 g) were detected in the fruits of the Ourous cultivar. The same cultivar displayed the highest antioxidant capacity against DPPH• free radical (595 mg AAE/100 g), ABTS•+ cation radical (839 mg TE/100 g), and ferric reducing antioxidant potential (704 mg AAE/100 g). All extracts manifested moderate antioxidant activities tested by phosphomolybdenum, NO•, and linoleic acid lipid peroxidation assays. These extracts also exhibited interesting levels of in vitro enzyme inhibition; the Ourous cultivar gave the best inhibitory activity against α-amylase and acetylcholinesterase with 45 and 37%, respectively. HPLC-DAD-MS detected a total of five compounds, with phenolic acids and flavonoids being the main phenolics identified in the extract. The phenolic composition exhibited significant variability among cultivars. Notably, the highest amounts were revealed in the Tazizaout cultivar, with the predominance of gallic acid. The results confirmed that the combination of UAE and NADESs provides a novel and important alternative to chemical solvents for sustainable and environmentally friendly extraction and can represent a good alternative in food and pharmaceutical industry applications

Effects of grape pomace polyphenolic extract (Taurisolo® ) in reducing tmao serum levels in humans: Preliminary results from a randomized, placebo-controlled, cross-over study

Trimethylamine N-oxide (TMAO) is considered a novel risk factor for cardiovascular diseases. Several studies demonstrated that polyphenols are able to inhibit the growth of TMA-producing bacterial strains, and resveratrol (RSV) reduced TMAO levels in mice. In the present study, we evaluated the TMAO-reducing effect of a novel nutraceutical formulation containing grape pomace extract in humans (Taurisolo&reg;). The Taurisolo&reg; polyphenol content was evaluated by a High Performance Liquid Chromatography-diode-array detector (HPLC-DAD) method, and RSV was monitored as an indicative marker. After in vitro GI digestion, intestinal bioaccessibility of RSV was 92.3%. A randomized, placebo-controlled, cross-over trial was carried out to evaluate the TMAO-reducing effect of Taurisolo&reg;. In acute, the maximum levels of RSV were detected both in serum and whole blood 60 min after the administration of Taurisolo&reg;; in chronic, a significant increase of RSV was detected in serum after the 4-week treatment. After 4 weeks, the levels of TMAO were significantly decreased in the treatment group compared to placebo (63.6% vs. 0.54%, respectively, P &lt; 0.0001). In conclusion, our data show that Taurisolo&reg; may represent a novel and useful natural remedy to reduce prognostic markers for incident cardiovascular events. Undoubtedly, further in vitro and in vivo studies need to be performed in order to elucidate possible mechanisms of action and corroborate our preliminary results

Resveratrol as a novel anti-herpes simplex virus nutraceutical agent: An overview

The herpes simplex virus (HSV) is a common human virus affecting many people worldwide. HSV infections manifest with lesions that occur in different parts of the body, including oral, ocular, nasal, and genital skin and mucosa. In rare cases, HSV infections can be serious and lethal. Several anti-HSV drugs have been developed, but the existence of mutant viruses resistant to these drugs led to the individuation of novel antiviral agents. Plant-derived bioactive compounds, and more specifically polyphenols, have been demonstrated to exert marked anti-HSV activity and, among these, resveratrol (RSV) would be considered a good candidate. The purpose of this manuscript is to review the available literature elucidating the efficacy of RSV against HSV and the main demonstrated mechanisms of action

Colon Bioaccessibility and Antioxidant Activity of White, Green and Black Tea Polyphenols Extract after In Vitro Simulated Gastrointestinal Digestion

The beneficial effects of the tea beverage are well-known and mainly attributed to polyphenols which, however, have poor bioaccessibility and bioavailability. The purpose of the present study was the evaluation of colon bioaccessibility and antioxidant activity of tea polyphenolic extract. An 80% methanolic extract (v/v) of tea polyphenols was obtained from green (GT), white (WT) and black tea (BT). Simulated gastrointestinal (GI) digestion was performed on acid-resistant capsules containing tea polyphenolic extract. The main tea polyphenols were monitored by HPLC-diode-array detector (DAD) method; in addition, Total Phenol Content (TPC) and antioxidant activity were evaluated. After GI digestion, the bioaccessibility in the colon stage was significantly increased compared to the duodenal stage for both tea polyphenols and TPC. Similarly, the antioxidant activity in the colon stage was significantly higher than that in the duodenal stage. Reasonably, these results could be attributable in vivo to the activity of gut microbiota, which is able to metabolize these compounds, generating metabolites with a greater antioxidant activity. Our results may guide the comprehension of the colon digestion of polyphenols, suggesting that, although poorly absorbed in the duodenum, they can exert their antioxidant and anti-inflammatory activities in the lower gut, resulting in a novel strategy for the management of gut-related inflammatory diseases

Lactofermented annurca apple puree as a functional food indicated for the control of plasma lipid and oxidative amine levels: Results from a randomised clinical trial

Atherosclerotic cardiovascular diseases are preferential targets of healthy diet and preventive medicine partially through strategies to improve lipid profile and counteract oxidative metabolites. Ninety individuals with cardiovascular disease (CVD) risk factors were randomized (1:1:1 ratio) to three arms, according to a four-week run-in, eight-week intervention, and four-week follow up study, testing the effects of a lactofermented Annurca apple puree (lfAAP), compared to unfermented apple puree (AAP) or probiotic alone (LAB) on plasma lipid profile and trimethylamine-N-oxide (TMAO) levels. By comparing the treatments, data indicated for the subjects tested with lfAAP a higher variation of the following serum parameters, in respect to the other treatment groups: high density lipoprotein cholesterol (HDL-C), +61.8% (p = 0.0095); and TMAO levels, &minus;63.1% (p = 0.0042). The present study would suggest lfAAP as an effective functional food for beneficial control of plasma HDL-C and TMAO levels