Almonds (Prunus Dulcis Mill. D. A. Webb): A Source of Nutrients and Health-Promoting Compounds.

Almonds (Prunus dulcis Miller D. A. Webb (the almond or sweet almond)), from the Rosaceae family, have long been known as a source of essential nutrients; nowadays, they are in demand as a healthy food with increasing popularity for the general population and producers. Studies on the composition and characterization of almond macro- and micronutrients have shown that the nut has many nutritious ingredients such as fatty acids, lipids, amino acids, proteins, carbohydrates, vitamins and minerals, as well as secondary metabolites. However, several factors affect the nutritional quality of almonds, including genetic and environmental factors. Therefore, investigations evaluating the effects of different factors on the quality of almonds were also included. In epidemiological studies, the consumption of almonds has been associated with several therapeutically and protective health benefits. Clinical studies have verified the modulatory effects on serum glucose, lipid and uric acid levels, the regulatory role on body weight, and protective effects against diabetes, obesity, metabolic syndrome and cardiovascular diseases. Moreover, recent researchers have also confirmed the prebiotic potential of almonds. The present review was carried out to emphasize the importance of almonds as a healthy food and source of beneficial constituents for human health, and to assess the factors affecting the quality of the almond kernel. Electronic databases including PubMed, Scopus, Web of Science and SciFinder were used to investigate previously published articles on almonds in terms of components and bioactivity potentials with a particular focus on clinical trials.

Understanding the Effect of Particle Size and Processing on Almond Lipid Bioaccessibility through Microstructural Analysis: From Mastication to Faecal Collection.

We have previously reported on the low lipid bioaccessibility from almond seeds during digestion in the upper gastrointestinal tract (GIT). In the present study, we quantified the lipid released during artificial mastication from four almond meals: natural raw almonds (NA), roasted almonds (RA), roasted diced almonds (DA) and almond butter from roasted almonds (AB). Lipid release after mastication (8.9% from NA, 11.8% from RA, 12.4% from DA and 6.2% from AB) was used to validate our theoretical mathematical model of lipid bioaccessibility. The total lipid potentially available for digestion in AB was 94.0%, which included the freely available lipid resulting from the initial sample processing and the further small amount of lipid released from the intact almond particles during mastication. Particle size distributions measured after mastication in NA, RA and DA showed most of the particles had a size of 1000 µm and above, whereas AB bolus mainly contained small particles (<850 µm). Microstructural analysis of faecal samples from volunteers consuming NA, RA, DA and AB confirmed that some lipid in NA, RA and DA remained encapsulated within the plant tissue throughout digestion, whereas almost complete digestion was observed in the AB sample. We conclude that the structure and particle size of the almond meals are the main factors in regulating lipid bioaccessibility in the gut.

Contribution of the Glucosinolate Fraction to the Overall Antioxidant Potential, Cytoprotection against Oxidative Insult and Antimicrobial Activity of Eruca sativa Mill. Leaves Extract.

BACKGROUND: Eruca sativa Mill. (Brassicaceae) is commonly utilized as an ingredient in salads and also as a folk remedy to treat various diseases. OBJECTIVE: The objective of this study was to establish the contribution of the glucosinolate (GLS) fraction to the overall antioxidant, cytoprotection against oxidative insult and antimicrobial properties of the hydro-alcoholic extract of E. sativa leaves from Sicily (Italy), characterized phytochemically. MATERIALS AND METHODS: The antioxidant activity was evaluated by different in vitro systems. The cytoprotective effect against hydrogen peroxide (H2O2)-induced oxidative stress was tested in human peripheral blood mononuclear cells (PBMCs). The antimicrobial potential against bacteria and fungi was assayed by standard methods. RESULTS: E. sativa extract exhibited both radical scavenging (50% inhibitory concentration [IC50] 1.04 ± 0.04 mg/mL) and ferrous ions-chelating activity (IC50 0.327 ± 0.0032 mg/mL) and mild reducing power; the GLS fraction showed chelating ability only (IC50 0.225 ± 0.009 mg/mL). In the experimental model of H2O2-induced oxidative stress in human PBMCs, a significant cytoprotective effect and a suppression of reactive oxygen species production by both extract and GLS fraction were observed (P < 0.001). E. sativa extract displayed moderate antimicrobial activity against Gram-positive bacteria, and Staphylococcus aureus was the most sensitive strain (minimum inhibitory concentration 0.125 mg/mL), whereas the GLS fraction was not active. CONCLUSION: GLSs are not involved in the primary antioxidant activity of E. sativa leaf extract but they are, almost in part, responsible for its ferrous ion-chelating properties. Iron-chelating compounds in E. sativa extract may protect cells under conditions of oxidative stress, and GLSs might play a chief role in this effect. SUMMARY: Eruca sativa Mill. leaf extract exhibited antioxidant activity in different in vitro systems, whereas the glucosinolate (GLS) fraction showed Fe2+-chelating ability onlyA significant cytoprotective effect and a suppression of intracellular reactive oxygen species production by both extract and GLS fraction were observed in human peripheral blood mononuclear cellsE. sativa extract displayed moderate antimicrobial activity against Gram-positive bacteria, whereas the GLS fraction was not active. Abbreviations used: GLS: Glucosinolate; H2O2: Hydrogen peroxide; PBMCs: Peripheral blood mononuclear cells; IC50: 50% inhibitory concentration; MIC: Minimum inhibitory concentration.

Antioxidant and Anti-inflammatory Properties of Algerian Thymelaea microphylla Coss. and Dur. Extracts.

BACKGROUND: Thymelaea microphylla Coss. et Dur. (Thymelaeaceae) (TM) is a rare medicinal plant endemic to Algeria. Leaves decoction is used in folk medicine for anticancer, anti-inflammatory, and antidiabetic properties. OBJECTIVE: Herein, the antioxidant and anti-inflammatory properties of different extracts from leaves and flowers of Algerian TM were evaluated. MATERIALS AND METHODS: The study was carried out by in vitro cell-free assays (antioxidant/radical properties), ex vivo experiments (inhibition of prostaglandin E2 and thromboxane B2 release in human whole blood) and in vitro experiments on cell systems (cytotoxicity on peripheral blood mononuclear cells, and protective effects on human vein endothelial cells exposed to TNF-α). RESULTS: The acetone TM extract showed significant antioxidant properties and excellent anti-inflammatory and cyclooxygenase-inhibitory activity, together with lack of toxicity on normal human blood cells; furthermore, it was able to protect endothelial cells against dysfunction induced by TNF-α, as shown by decrease in cell death, e-selectin expression and leukocyte adhesion. CONCLUSION: On these bases, TM leaves and flowers appear to be a good source of bioactive compounds with significant antioxidant and antiinflammatory capability, and potentially effective in prevention and treatment of pathological conditions related to oxidative stress and inflammation, such as endothelial dysfunction. SUMMARY: Thymelaea microphylla leaves and flowers are a good source of bioactive compounds with significant antioxidant/free radical scavenger and antiinflammatory activity.The acetone extract from leaves and flowers of Algerian Thymelaea microphylla possesses excellent cyclooxygenase-inhibitory activity.This extract is able to protect against endothelial dysfunction, an early event in development of atherosclerosis and vascular diseases. Abbreviations used: TM: Thymelaea microphylla; BCB: Beta-carotene bleaching; AcE: Acetone extract; PGE2: Prostaglandin E2; TxB2: Thromboxane B2; FL: Fluorescein; Cat: Catechin; DPPH: 2,2-diphenyl-1-picrylhydrazyl; ABTS: 2,2'-azinobis-(3-ethyl-benzothiazolin-6-sulfonic acid)+; Que: Quercetin; ORAC: Oxygen radical absorbance capacity; AAPH: 2,2'-azobis (2-methylpropionamidine)dihydrochloride; PMS/NADH: Phenazine methosulfate/nicotinamide adenine dinucleotide; HUVECs: Human umbilical vein endothelial cells.

Selective COX-2 inhibitory properties of dihydrostilbenes from liquorice leaves--in vitro assays and structure/activity relationship study.

Three dihydrostilbenes belonging to the polyphenol pool characterized in the leaves of Sicilian liquorice (Glycyrrhiza glabra L.) have been tested for their antioxidant and anti-inflammatory activity. The three dihydrostilbenes (PA-82, GA-23, DO-07) were in vitro tested to evaluate their capability to scavenge the stable radical 1,1-diphenyl-2-picrylhydrazyl (DPPH), and to decrease thromboxane B2 (TxB2) and prostaglandin E2 (PGE2) release in human whole blood samples. On the basis of the observed capability of these compounds to affect the cell COX-1/COX-2 pathway, a molecular docking study was carried out in order to understand in detail the ability of these compounds to bind to COX-1 and COX-2. The results show that the liquorice dihydrostilbenes are preferred ligands for COX-2 rather than for COX-1, providing a good rational for the observed selectivity in ex vivo experiments. Therefore, they appear to be good candidates for employment in human therapy against inflammation-related pathological conditions.

Cytotoxic effects induced in vitro by organic extracts from urban air particulate matter in human leukocytes.

Urban areas represent major pollution sources as a result of anthropogenic activities located in these districts. Among the legislated air pollutants, polycyclic aromatic hydrocarbons (PAHs), which are mostly adsorbed on the surface of dust particles, are known for their adverse health effects. The present study has been carried out to examine the cytotoxic effects induced in vitro on human peripheral monocytes (PBMCs) by extractable organic matter (EOM) from PM10 (characterized for its PAH content) collected at four sites in the urban center of Messina, Italy. Chromatographic analyses showed the presence of PAHs in all EOM. Only EOM from one site induced a marked cell death probably resulting from the highest PAH content in this sample. Conversely, apoptosis activation was evident after PBMC exposure to all the EOM tested. These apoptotic effects do not appear related only to the total PAH content, but are probably influenced by chemical composition. In conclusion, our findings confirm that the cytotoxic potential of organic matter associated to ambient respirable air particles depends predominantly on the quantity and quality of the chemicals contained in it. In particular, the present data strongly evidence that the only evaluation of air concentration of particulate matter and benzo[a]pyrene, as well as the generally used risk models based on additivity, are not sufficient to evaluate air quality and PAH effect on human health because they do not take into account the possible inhibitory or synergic or antagonistic effect of combined exposure and the interference of other organic compounds present in respirable matter.