Optimization of total anthocyanin content and antioxidant activity of a Hibiscus sabdariffa infusion using response surface methodology

Hibiscus sabdariffa L. calyces are underutilized sources of health-promoting anthocyanins. Infusions are the most common way to consume them, but because anthocyanins are thermosensitive, prolonged extraction times at high temperatures may reduce their bioactivities, suggesting the need to identify optimal preparation conditions. Response surface methodology was used to establish calyces-to-water ratio (X1: 1–20 g/100 mL), temperature (X2: 70–100 °C), and time (X3: 1–30 min) that would produce an infusion with optimized total anthocyanin content (TAC) and antioxidant activity. Under optimum conditions (X1=10 g/100 mL, X2=88.7 °C, and X3=15.5 min) TAC was 132.7±7.8 mg cyanidin-3-glucoside equivalents (C3G)/100 mL, and antioxidant activity was 800.6±69.9 (DPPH assay), and 1792.0±153.5 (ABTS assay) μmol Trolox equivalents (TE)/100 mL. Predicted and experimental results were statistically similar. Identifying ideal processing conditions can promote consumption of an H. sabdariffa-based functional beverage with high anthocyanin content and antioxidant activity that exert health-promoting bioactivities on the consumer

Pomegranate (Punica granatum L.) Peel Extracts as Antimicrobial and Antioxidant Additives Used in Alfalfa Sprouts

Aqueous and ethanolic pomegranate peel extracts (PPE) were studied as a source of phenolic compounds with antimicrobial, anti-quorum sensing, and antioxidant properties. The aqueous extract showed higher total phenolic and flavonoid content (153.43 mg GAE/g and 45.74, respectively) and antioxidant capacity (DPPH radical inhibition: 86.12%, ABTS radical scavenging capacity: 958.21 mg TE/dw) compared to the ethanolic extract. The main phenolic compounds identified by UPLC-DAD were chlorogenic and gallic acids. The aqueous PPE extract showed antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, Candida tropicalis (MICs 19–30 mg/mL), and anti-quorum sensing activity expressed as inhibition of Chromobacterium violaceum violacein production (%). The aqueous PPE extracts at 25 mg/mL applied on alfalfa sprouts reduced psychrophilic bacteria (1.12 Log CFU/100 g) and total coliforms (1.23 Log CFU/100 g) and increased the antioxidant capacity of the treated sprouts (55.13 mol TE/100 g (DPPH) and 126.56 mol TE/100 g (ABTS)) compared to untreated alfalfa. This study emphasizes PPE’s antioxidant and antimicrobial activities in alfalfa sprouts preservation

Antimicrobial and antioxidant properties of byproduct extracts of mango fruit

Byproducts of fruit processing could have higher content of phenolic compounds that can act as antimicrobial and antioxidant agents. In this context, the main objective of this study was to obtain extracts from peel, seed, and unused flesh of Haden, Ataulfo and Tommy Atkins mango varieties, in order to measure their antioxidant and antimicrobial properties. The extraction was performed using different methods, such as methanolic-polar, methanolic-non-polar, ethanolic-polar, ethanolic-non-polar and water infusion. The total phenolic content of the ethanolic-non-polar extract from seed of mango Haden showed 875.06 mg/g, DPPH EC50: 0.04 mg/mL, cau-sing a 100 % inhibition of bacteria pathogens applying 25 mg/mL and inhibition of 89.78 % against Alternaria applying 6.25 mg/mL. The flesh always showed the lowest content and bioactivity of the tested parameters. These results demonstrate the antimicrobial and antioxidant potential uses of fruit byproducts as sources of bioactive compounds

Content of bioactive compounds and their contribution to antioxidant capacity during ripening of pineapple (Ananas comosus L.) cv Esmeralda

Pineapple (Ananas comosus L.) cv Esmeralda is a commercially important fruit with many bioactive compounds like vitamin C, β-carotene, phenolic compounds and flavonoids, which have been reported only for fruits of commercial maturity. Our objective was to evaluate changes in concentration of main pineapple bioactives, their contribution to total antioxidant capacity and enzyme activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD) during pineapple ripening. Fruits were grouped into four ripening stages (RS) according to their weight, size and percentage of yellow skin color (RS1: 100% green, RS2: up to 30% yellow, RS3: 30% - 75% yellow, RS4: 75% - 100% yellow). Vitamin C content initially increased, and decreased at RS4; β-carotene, phenolics and antioxidant capacity increased gradually. Phenolics contributed over 40% of antioxidant capacity, followed by vitamin C and β-carotene. Major phenolic compounds identified were gallic acid, catechin and epicatechin. PAL and POD activity increased with ripening and correlated with concentration of phenolics. No PPO activity was quantified. We concluded that ripening of pineapple cv Esmeralda alters the concentration of bioactive compounds. Phenolic compounds, particularly gallic acid, exert the most antioxidant capacity during all RS, even if other compounds have higher concentrations

Antioxidant and Antimicrobial Capacity of Phenolic Compounds of Mango (Mangifera indica L.) Seed depending upon the Extraction Process

The extraction method is critical for the recovery of phenolic compounds. The main goal was to evaluate the effect of an extraction process from mango seed on their phenolic profile, antioxidant and antimicrobial capacities. Phenolic extraction was performed in different steps: maceration, alkaline hydrolysis, acid/alkaline hydrolysis, polar and non-polar fraction of an ethyl acetate separation.The macerated extract showed a higher variety of polyphenols from mango seed:gallic (138.36 µg/g dry weight), coumaric (65.36 µg/g), ferulic (1376.67 µg/g) , chlorogenic (57.75 µg/g) anddicaffeoylquinic (219.29 µg/g) acids, catechin (16.78 µg/g) and rutin (6678.62µg/g). In alkaline hydrolyzed extract most of these compounds were lost, ferulic acid decreased 1356.77 µg/g dw and gallic acid increased 1383.89 µg/g dw. Gallic and chlorogenic acids increased 165 and 969. 45 µg/g dw respectively in acid/alkaline hydrolyzed, 109.57 and 841.38 µg/g dw respectively in non-polar and 277.15 and 77.88 µg/g dw respectively in polar extracts related to the macerated extract. Rutin was found only in acid/hydrolyzed and non-polar extract in lesser amount (87.62 and 78.51 µg/g dw) compared to macerated extract. The content of phenolic compounds was higher for the macerated extract (phenols=484.42 mg GAE/g and flavonoids=86.59 mg QE/g) than for the other steps. Acid/alkaline hydrolysis increased the antioxidant activity (1787.67 μmol TE/g for DPPH and 3692.86 μmol TE/g for TEAC); while the alkaline hydrolysis increased the antimicrobial effectivity (MIC=2.5 mg/mL for bacteria and 0.5 mg/mL for yeast). Results indicate that the acid or alkaline hydrolysis yields a stronger antioxidant and antimicrobial extract

Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning