Contribution of anthocyanin fraction to the antioxidant properties of wine

The wine is a beverage with an important antioxidant efficiency which is attributed to their bioactives compounds, especially polyphenols. The anthocyanins are the main phenolic compounds of red wine and its consumption has been partially related with the "French Paradox". The aim of the present work was to evaluate the contribution of the anthocyanins to the antioxidant properties of red wines. So, total antioxidant capacity (TAC), hydroxyl and superoxide scavenger activity and lipid peroxidation of 80 Spanish red wines and their anthocyanins fractions have been assessed for ABTS, DPPH, DMPD, and FRAP methods, hydroxyl radical (HRSA), superoxide radical scavenger activity (SRSA) and ABAP-lipid peroxidation (ABAP-LP). The results showed that free anthocyanins fraction are main responsible of the total antioxidant capacity of red wines correlated with electron transference processes. In similar way, free anthocyanins are the maximum responsible of HRSA scavenger activity of red wines, contributing less extensively to their SRSA capacity or to their protective action on lipid peroxidation. Furthermore, simple anthocyanins exert a low action in TAC process involved with proton transference. Glycosilated and methoxylic anthocyanins as malvidin-3-glucoside, seem to be the type of anthocyanins with higher participation on the antioxidant effect of red wine.     

An anthocyanin-enriched extract from strawberries delays disease onset and extends survival in the hSOD1G93A mouse model of amyotrophic lateral sclerosis

Objective: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting from the death of motor neurons in the brain, brain stem, and spinal cord. Several processes such as oxidative stress, neuroinflammation, and neuronal apoptosis, contribute to disease progression. Anthocyanins are flavonoid compounds derived from fruits and vegetables that possess antioxidant, anti-inflammatory, and anti-apoptotic abilities. Thus, these unique compounds may provide therapeutic benefit for the treatment of ALS.

Methods: We used the G93A mutant human SOD1 (hSOD1^G93A) mouse model of ALS to assess the effects of an anthocyanin-enriched extract from strawberries (SAE) on disease onset and progression. Mice were administered SAE orally beginning at 60 days of age until end-stage such that mice received 2?mg/kg/day of the extract's primary anthocyanin constituent. Clinical indices of disease were assessed until mice were sacrificed at end-stage. Histopathological indices of disease progression were also evaluated at 105 days of age.

Results: hSOD1^G93A mice supplemented with SAE experienced a marked (～17 day) delay in disease onset and a statistically significant (～11 day) extension in survival in comparison to their untreated mutant counterparts. Additionally, SAE-treated hSOD1^G93A mice displayed significantly preserved grip strength throughout disease progression. Histopathological analysis demonstrated that SAE supplementation significantly reduced astrogliosis in spinal cord, and preserved neuromuscular junctions (NMJs) in gastrocnemius muscle.

Discussion: These data are the first to demonstrate that anthocyanins have significant potential as therapeutic agents in a preclinical model of ALS due to their ability to reduce astrogliosis in spinal cord and preserve NMJ integrity and muscle function. Therefore, further study of these compounds is warranted in additional preclinical models of ALS and other neurodegenerative diseases.     

Determination of anthocyanins from black carrots by UHPLC-PDA after ultrasound-assisted extraction

Anthocyanins from black carrots (Daucus carota ssp. sativus var. atrorubens Alef.) are widely applied to impart bright red hues to foods such as beverages, fruit preparations, and confectionary. Highly efficient methods for their analyses may be instrumental for manufacturers of coloring foodstuff and for plant breeders to select highly pigmented black carrot varieties. For this purpose, a rapid and exhaustive ultrasound-assisted extraction procedure for anthocyanins was developed and validated. Thereby, deteriorative enzymes like polyphenol oxidase and peroxidase were inactivated. Extraction required only 60 s, yielding coefficients of variation (CVs) for intra-day and inter-day repeatability of ≤4.4 and 4.7%, respectively. For post-extractive quantitation of black carrot anthocyanins, a rapid UHPLC-PDA method was developed and validated. Compared to HPLC separation on a core-shell-column, UHPLC separation time (4.5 min) was 8.2 times faster and solvent consumption 92% less. Limits of detection and quantitation were fully satisfactory. Moreover, stability of non-acylated pigments used as reference compounds was acceptable for 24 h at room temperature, and within 4.5 months of storage time at −20 °C and −80 °C, pigment concentration remained unchanged. Two black carrot varieties were analyzed applying the proposed method, and the results were compared to previously published data.     

Anthocyanins from purple sweet potato attenuate dimethylnitrosamine-induced liver injury in rats by inducing Nrf2-mediated antioxidant enzymes and reducing COX-2 and iNOS expression

Anthocyanins of the purple sweet potato exhibit antioxidant and hepatoprotective activities via a multitude of biochemical mechanisms. However, the signaling pathways involved in the actions of anthocyanin-induced antioxidant enzymes against chronic liver injury are not fully understood. We examined whether an anthocyanin fraction (AF) from purple sweet potato may prevent dimethylnitrosamine (DMN)-induced liver injury by inducing antioxidants via nuclear erythroid 2-related factor 2 (Nrf2) pathways and by reducing inflammation. Treatment with AF attenuated the DMN-induced increased serum alanine aminotransferase and aspartate aminotransferase activities. It also prevented the formation of hepatic malondialdehyde and the depletion of glutathione and maintained normal glutathione-S-transferase (GST) activity in the livers of DMN-intoxicated rats. Furthermore, AF increased the expression of Nrf2, NADPH:quinine oxidoreductase-1, heme oxygenase-1, and GSTα, which were reduced by DMN, and decreased the expression of cyclooxygenase-2 and inducible nitric oxide synthase. An increase in the nuclear translocation of nuclear factor kappa B (NF-κB) was observed in the DMN-induced liver injury group, but AF inhibited this translocation. Taken together, these results demonstrate that AF increases the expression of antioxidant enzymes and Nrf2 and at the same time decreases the expression of inflammatory mediators in DMN-induced liver injury. These data imply that AF induces antioxidant defense via the Nrf2 pathway and reduces inflammation via NF-κB inhibition.     

Color and chemical stability of spray-dried blueberry extract using mesquite gum as wall material

Blueberry is an important source of anthocyanins, which are highly colored substances recognized for their antioxidant activity. One of the drawbacks of using anthocyanins as food colorant is their low stability. The objective of this study was to evaluate the variations found in color and concentration of the compounds (which produce the color) on spray-dried powders, obtained from blueberry extracts with added mesquite gum. Ethanolic blueberry extracts were concentrated until reaching 35% of soluble solids. They were then spray-dried using mesquite gum as an encapsulating agent at 140 and 160 °C of air inlet temperature and 8.5, 9.1 and 9.6 mL/min of feeding rates. The lowest losses in the content of total phenolics, total anthocyanins, and color of the samples were found in samples dried at 140 °C and 9.1 mL/min. The microencapsulates that were stored for 4 weeks at 4 °C in the absence of light presented low degradation of phenolics (10%), anthocyanins (7%) and antioxidant activity (15%). Final color values were L = 39.87, C = 47.83 and H° = 28.59, with a total color difference ΔE = 5.     

Photoprotective Potential of Anthocyanins Isolated from Acanthopanax divaricatus Var. albeofructus Fruits against UV Irradiation in Human Dermal Fibroblast Cells

Ultraviolet (UV) A penetrates deeply into the skin and induces the generation of reactive oxygen species (ROS) causing damage to fibroblasts, which leads to aging of the skin. However, the body has developed an antioxidant defence system against the harmful effects of ROS. Enzymes such as superoxide dismutase (SOD) and catalase (CAT) play critical roles on the removal of excess ROS in living organisms. In this study, the antioxidant activities of anthocyanins (cyanidin 3-galactoside and cyanidin 3-lathyroside) from Acanthopanax divaricatus var. albeofructus (ADA) fruits were investigated by xylenol orange, thiobarbituric acid reactive substances (TBARS), and antioxidant enzyme assay. As a result, generation of H₂O₂ and lipid peroxide induced by UVA-irradiation in human dermal fibroblast (HDF-N) cells was reduced by treatment of anthocyanins. Also, augmented enzyme (SOD and CAT) activities were observed in UVA-irradiated cells when treated with anthocyanin. In conclusion, the results obtained show that anthocyanins from ADA fruits are potential candidates for the protection of fibroblast against the damaging effects of UVA irradiation. Furthermore, anthocyanin may be a good candidate for antioxidant agent development.     

Effect of Hibiscus sabdariffa on obesity in MSG mice

The aim of the present investigation was determine whether a standardized Hibiscus sabdariffa calyces aqueous extract has an effect on body weight in an obese animal model induced by the administration of monosodium glutamate. Hibiscus sabdariffa aqueous extract, containing 33.64 mg of total anthocyanins per each 120 mg of extract, was orally administered (120 mg/kg/day) for 60 days to healthy and obese mice, and body weight gain, food and liquid intake, aspartate aminotransferase (AST), alanine aminotransferase (ALT), cholesterol, and triglycerides levels were measured. Hibiscus sabdariffa administration significantly reduced body weight gain in obese mice and increased liquid intake in healthy and obese mice. ALT levels were significantly increased on the 15th and 45th days in obese mice, but AST levels did not show significant changes. Mortality was not observed in the Hibiscus sabdariffa treated groups. Triglycerides and cholesterol levels showed non-significant reductions in animals treated with Hibiscus sabdariffa. Our data confirm the anti-obesity effect of Hibiscus sabdariffa reported by the Mexican population.