Bioactive Compounds of Aristotelia chilensis Stuntz and their Pharmacological Effects

Maqui berry (Aristotelia chilensis) extract improves memory and decreases oxidative stress in male rat brain exposed to ozone

Introduction: Prolonged ozone exposure can produce a state of oxidative stress, which in turn causes alterations in the dynamics of the brain and affects memory and learning. Moreover, different investigations have shown that high flavonoid content berries show a great antioxidant activity. The relationship between the protective effect of the maqui berry extract and its antioxidant properties in the brain has not been studied in depth. Objectives: The present study evaluated whether the protection exerted by the aqueous extract of maqui berry in brain regions associated with cognitive performance is due to its antioxidant capacity. Methods: Sprague Dawley rats were exposed to 0.25 ppm ozone and administered with maqui berry extracts. At the end of the treatments, spatial learning and short- and long-term memory were evaluated, as well as oxidative stress markers. Results: The administration of 50 and 100 mg/kg of the aqueous extract of maqui berry was effective in preventing the cognitive deficit caused by chronic exposure to ozone. The antioxidant effect of the administration of maqui berry was analyzed in the prefrontal cortex, hippocampus, and amygdala. Oxidative stress markers levels decreased and the enzymatic activity of superoxide dismutase diminished in animals exposed to ozone treated with the 50 mg/kg dose of maqui berry. Discussion: These results show a relationship between protection at the cognitive level and a decrease in oxidative stress markers, which suggests that the prevention of cognitive damage is due to the antioxidant activity of the maqui berry.

Ethnopharmacology, Phytochemistry and Biological Activities of Native Chilean Plants

The native flora of Chile has unique characteristics due to the geographical situation of the country, with the vast desert in the North, Patagonia in the South, the Andean Mountains on the east and the Pacific Ocean on the west. This exclusivity is reflected in high concentrations of phytochemicals in the fruits and leaves of its native plants. Some examples are Aristotelia chilensis (Molina), Stuntz (maqui), Berberis microphylla G. Forst. (calafate), Peumus boldus Molina (boldo), Ribes magellanicum Poir. (Magellan currant), Ugni molinae Turcz. (murtilla), Rubus geoides Sm. (miñe miñe), Drimys winteri J.R.Forst. & G.Forst. (canelo), Luma apiculata (DC.) Burret (arrayán) distributed throughout the entire Chilean territory. Some of these Chilean plants have been used for centuries in the country's traditional medicine. The most recent studies of phytochemical characterization of parts of Chilean plants show a wide spectrum of antioxidant compounds, phenolic components, terpenoids and alkaloids, which have shown biological activity in both in vitro and in vivo studies. This manuscript covers the entire Chilean territory characterizing the phytochemical profile and reporting some of its biological properties, focusing mainly on antioxidant, anti-inflammatory, antimicrobial, chemopreventive and cytotoxic activity, and potential against diabetes, metabolic syndrome and gastrointestinal disorders.

The Reproductive Toxicity Associated with Dodonaea viscosa, a Folk Medicinal Plant in Saudi Arabia

Dodonaea viscosa is a medicinal plant which is being used to treat various diseases in humans. The available safety data suggest that the plant does not produce any side effects, or toxicity, in tested adult experimental animals. However, the influence of D. viscosa on fetus or embryonic development is largely not known. This study was conducted in order to find out the reproductive toxicity of D. viscosa in experimental animals. Zebrafish embryos were used as the in vivo developmental toxicity animal model. Methanolic crude extract, hexane, chloroform, and butanol fractions were prepared from the leaves of D. viscosa. Zebrafish embryos were exposed to serial dilution of crude extract and other fractions. The crude extract and hexane fraction induced higher level of toxicity in zebrafish embryos as compared to chloroform and butanol fractions. The phenol and flavonoid estimation revealed that crude leaves extract and hexane fractions had lower content of phenol and flavonoid. Two major compounds, phytol and methyl ester, of hexadecanoic acid were identified by gas chromatography and mass spectrophotometry (GC-MS) analysis. More detailed studies are needed to check the toxicity of D. viscosa in pregnant experimental animals; however, the results from this study have shown that D. viscosa possesses reproductive toxicity and its use and doses must be carefully monitored in pregnant patients.

Evaluation of Color, Texture, Sensory and Antioxidant Properties of Gels Composed of Freeze-Dried Maqui Berries and Agave Sugar

The study aimed to determine the textural, sensory, and antioxidant properties of gels composed of maqui (Aristotelia chilensis) berries. These freeze-dried berries were tested in a powdered form as an additive (0–5%) to agave sugar (20%) gels. Freeze-dried maqui powdered berries were dark purple to almost black in color and were characterized by an L* value of 16.3, an a* value of 8.3, and a b* value of −9.6. The b* values decreased from 11.8 to 2.3 with the increase in the amount of berry powder. There were no significant changes in the color of gels composed of berries at 4% and 5% concentration. Gels lost (almost twice) their hardness as the amount of maqui increased. The lowest values of hardness and the highest values of elasticity, springiness, gumminess, and chewiness were observed at 4% concentration of dried berries. The type of sugar did not affect the lightness of the gels (L* parameter) and the a* value. The assessors evaluated the gels composed of agave sugar (20%) and 4% maqui and 0.5% citric acid to be the best. Phenolic content and antioxidant activity were significantly higher in these gels compared to the control gels. After obtaining this low sugar gels, consumers could enrich their diets with healthier products.

Effects of drying processes on composition, microstructure and health aspects from maqui berries

The aim of this study is to determine the effects of different drying methods, including freeze drying (FD), convective drying, sun drying, infrared drying and vacuum drying (VD), on the chemical composition and microstructure of maqui berries as well as their anti-inflammatory and antidiabetic activities. Results showed that all dried samples have high unsaturated fatty acids contents (up to 83%) and high total dietary fiber contents (above 50%). Also, one hundred grams of dried berries provide between 11 and 21% of the recommended daily intake of α-tocopherol. Moreover, all dried maqui extracts reduced topical inflammation in treated mice. The highest anti-inflammatory effect against phorbol 12-myristate 13-acetate was found for VD and FD samples. Also, all dried maqui extracts showed antidiabetic activity by inhibiting α-glucosidase activity. The highest α-glucosidase inhibition activity was found for FD samples. The different biological activities of the dried maqui berries were related to differences in the extractability of metabolites due to microstructural changes during drying. The results indicated the potential use of dried maqui as a food ingredient with high unsaturated fatty acids, dietary fiber and α-tocopherol or as a natural extract with therapeutic agents.

Potent Vasodilator and Cellular Antioxidant Activity of Endemic Patagonian Calafate Berries (Berberis microphylla) with Nutraceutical Potential

Hydroalcoholic extracts of Patagonian Calafate berry (Berberis microphylla) contain mono or disaccharide conjugated anthocyanins and flavonols. The Liquid Chromatography-Mass Spectrometry (LC-MS) chemical extract profile identified glycosylated anthocyanidins such as delphinidin-, petunidin- and malvidin-3-glucoside as the major constituents. The predominant flavonols were 3-O substituents quercetin-rutinoside or -rhamnoside. Anthocyanins doubled flavonols in mass (13.1 vs. 6 mg/g extract). Polyphenols vascular actions were examined in the rat arterial mesenteric bed bioassay; extract perfusion elicited concentration-dependent vasodilatation mimicked by conjugated anthocyanins standards. Vascular responses of main glycosylated anthocyanins were endothelium-dependent (p < 0.001) and mediated by NO production (p < 0.05). The anthocyanins antioxidant activity determined in isolated endothelial cells (CAA) showed a reduced redox potential as compared to the extract or quercetin. While in the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, the anthocyanins showed an equivalent quercetin potency, the extract was 15-fold less active, proposing that the anthocyanin-induced vasodilation is not due to an antioxidant mechanism. The extract shows promising commercial nutraceutical potential.

Usage, biological activity, and safety of selected botanical dietary supplements consumed in the United States

In view of the continuous growth of the botanical dietary supplement industry and the increased popularity of lesser known or exotic botanicals, recent findings are described on the phytochemical composition and biological activities of five selected fruits consumed in the United States, namely, açaí, noni, mangosteen, black chokeberry, and maqui berry. A review of the ethnomedicinal uses of these plants has revealed some similarities ranging from wound-healing to the treatment of fever and infectious diseases. Laboratory studies on açaí have shown both its antioxidant and anti-inflammatory activities in vitro, and more importantly, its neuroprotective properties in animals. Anthraquinones and iridoid glucosides isolated from noni fruit induce the phase II enzyme quinone reductase (QR), and noni fruit juice exhibited antitumor and antidiabetic activities in certain animal models. Antitumorigenic effects of mangosteen in animal xenograft models of human cancers have been attributed to its xanthone content, and pure α-mangostin was shown to display antineoplastic activity in mice despite a reported low oral bioavailability. Work on the less extensively investigated black chokeberry and maqui berry has focused on recent isolation studies and has resulted in the identification of bioactive secondary metabolites with QR-inducing and hydroxyl-radical scavenging properties. On the basis of the safety studies and toxicity case reports described herein, these fruits may be generally considered as safe. However, cases of adulteration found in a commercialized açaí product and some conflicting results from mangosteen safety studies warrant further investigation on the safety of these marketed botanical dietary supplements.

Bioassay-Guided Isolation of Antioxidant and Cytoprotective Constituents from a Maqui Berry (Aristotelia chilensis) Dietary Supplement Ingredient As Markers for Qualitative and Quantitative Analysis

Bioassay-guided phytochemical investigation of a commercially available maqui berry (Aristotelia chilensis) extract used in botanical dietary supplement products led to the isolation of 16 compounds, including one phenolic molecule, 1, discovered for the first time from a natural source, along with several known compounds, 2-16, including three substances not reported previously in A. chilensis, 2, 14, and 15. Each isolate was characterized by detailed analysis of NMR spectroscopic and HRESIMS data and tested for their in vitro hydroxyl radical scavenging and quinone-reductase inducing biological activities. A sensitive and accurate LC-DAD-MS method for the quantitative determination of the occurrence of six bioactive compounds, 6, 7, 10-12, and 14, was developed and validated using maqui berry isolates purified in the course of this study as authentic standards. The method presented can be utilized for dereplication efforts in future natural product research projects or to evaluate chemical markers for quality assurance and batch-to-batch standardization of this botanical dietary supplement component.

The chilean superfruit black-berry Aristotelia chilensis (Elaeocarpaceae), Maqui as mediator in inflammation-associated disorders

The effects of phytochemicals occurred in fractions and extracts of fruits of "Maqui-berry" (Aristotelia chilensis), on the expression of cyclooxygenase-2 (COX-2), inducible-nitric oxide synthases (iNOS) and the production of proinflammatory mediators were investigated in lipopolysaccharide (LPS)-activated murine macrophage RAW-264 cells, as well as their antioxidant activities. The MeOH extract (A), acetone/methanol extract (B), fractions F3, F4, subfractions (SF4-SF6, SF7, SF8-SF10, SF11-SF15, SF16-SF20), quercetin, gallic acid, luteolin, myricetin, mixtures M1, M2 and M3 exhibited potent anti-inflammatory and antioxidant activities. The results indicated that anthocyanins, flavonoids and its mixtures suppressed the LPS induced production of nitric oxide (NO), through the down-regulation of iNOS and COX-2 protein expressions and showed a potent antioxidant activity against SOD, ABTS, TBARS, ORAC, FRAP and DCFH. The inhibition of enzymes and NO production by selected fractions and compounds was dose-dependent with significant effects seen at concentration as low as 1.0-50.0 (ppm) and 5.0-10.0 μM, for samples (extracts, fractions, subfractions and mixtures) and pure compounds, respectively. Thus, the phenolics (anthocyanins, flavonoids, and organic acids) as the fractions and mixtures may provide a potential therapeutic approach for inflammation associated disorders and therefore might be used as antagonizing agents to ameliorate the effects of oxidative stress.

Delphinidin-Rich Maqui Berry Extract (Delphinol®) Lowers Fasting and Postprandial Glycemia and Insulinemia in Prediabetic Individuals during Oral Glucose Tolerance Tests

Delphinidin anthocyanins have previously been associated with the inhibition of glucose absorption. Blood glucose lowering effects have been ascribed to maqui berry (Aristotelia chilensis) extracts in humans after boiled rice consumption. In this study, we aimed to explore whether a standardized delphinidin-rich extract from maqui berry (Delphinol) affects glucose metabolism in prediabetic humans based on glycemia and insulinemia curves obtained from an oral glucose tolerance test (OGTT) after a challenge with pure glucose. Volunteers underwent four consecutive OGTTs with at least one week washout period, in which different doses of Delphinol were administered one hour before glucose intake. Delphinol significantly and dose-dependently lowered basal glycemia and insulinemia. Lower doses delayed postprandial glycemic and insulinemic peaks, while higher doses reversed this tendency. Glycemia peaks were dose-dependently lowered, while insulinemia peaks were higher for the lowest dose and lower for other doses. The total glucose available in blood was unaffected by treatments, while the total insulin availability was increased by low doses and decreased by the highest dose. Taken together, these open exploratory results suggest that Delphinol could be acting through three possible mechanisms: by inhibition of intestinal glucose transporters, by an incretin-mediated effect, or by improving insulin sensitivity.

Effect of Flavonoids on Oxidative Stress and Inflammation in Adults at Risk of Cardiovascular Disease: A Systematic Review

Oxidative stress (OS) and inflammatory processes initiate the first stage of cardiovascular disease (CVD). Flavonoid consumption has been related to significantly improved flow-mediated dilation and blood pressure. Antioxidant and anti-inflammatory mechanisms are thought to be involved. The effect of flavonoids on markers of oxidative stress and inflammation, in at risk individuals is yet to be reviewed. Systematic literature searches were conducted in MEDLINE, Cochrane Library, CINAHL and SCOPUS databases. Randomised controlled trials in a Western country providing a food-based flavonoid intervention to participants with one or two modifiable risk factors for CVD measuring a marker of OS and/or inflammation, were included. Reference lists were hand-searched. The Cochrane Collaboration Risk of Bias Tool was used to assess study quality. The search strategy retrieved 1248 articles. Nineteen articles meeting the inclusion criteria were reviewed. Eight studies were considered at low risk of bias. Cocoa flavonoids provided to Type 2 diabetics and olive oil flavonoids to mildly-hypertensive women reduced OS and inflammation. Other food sources had weaker effects. No consistent effect on OS and inflammation across patients with varied CVD risk factors was observed. Study heterogeneity posed a challenge for inter-study comparisons. Rigorously designed studies will assist in determining the effectiveness of flavonoid interventions for reducing OS and inflammation in patients at risk of CVD.