Rapid quantitative analysis of individual anthocyanin content based on high-performance liquid chromatography with diode array detection with the pH differential method

Recovering high value-added anthocyanins from blueberry pomace with ultrasound-assisted extraction

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Food waste blueberry pomace offers a high potential to recover anthocyanins.

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Ultrasonic-assisted extraction of anthocyanins was optimized by Box-Behnken design.

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The optimal parameters of ultrasonic treatment were 40 °C and 400 W for 40 min.

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Highly purified blueberry anthocyanins were obtained after SCX cation exchange.

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Malvidin was the main anthocyanins in the purified fractions from blueberry pomace.

Food waste is a potential source to replace fresh materials for obtaining functional ingredients. Blueberry pomace contains considerable amounts of anthocyanins. In this study, we investigated ultrasonic-assisted extraction (UAE) of anthocyanins from blueberry pomace. We used a Box-Behnken design (BBD) to screen and optimize the important factors influencing yield. The optimum extraction conditions were a temperature of 40 °C, an ultrasonic power of 400 W and an extraction time of 40 min. The optimum yield was 108.23 mg/100 g DW. In addition, we used a cation column to separate anthocyanins, and optimized the chromatographic conditions of HPLC to analyze and identify the main anthocyanins. Thirteen anthocyanins were found in blueberry pomace, of which Malvidin-3-Galactoside (22.65 %) was the highest. These findings provide a theoretical basis and optimized process parameters for the recovery of high value-added anthocyanins from blueberry pomace with ultrasound-assisted extraction, thus facilitating the comprehensive utilization of blueberry pomace.

Probiotics in anthocyanin-rich fruit beverages: research and development for novel synbiotic products

Anthocyanin-rich fruit beverages are of special interest as functional products due to their antioxidant activity, antimicrobial properties against pathogens, and, more recently, evidence of prebiotic potential. The stability and bioactivity of anthocyanins, probiotics, prebiotics, and synbiotics have been extensively documented in beverage models and reviewed separately. This review summarizes the most recent works and methodologies used for the development of probiotic and synbiotic beverages based on anthocyanin-rich fruits with a synergistic perspective. Emphasis is made on key optimization factors and strategies that have allowed probiotic cultures to reach the minimum recommended doses to obtain health benefits at the end of the shelf life. The development of these beverages is limited by the high acidity and high content of phenolic compounds in anthocyanin-rich fruits. However, a proper selection of probiotic strains and strategies for their media adaptation may improve their viability in the beverages. Fermentation increases the viability of the probiotic cultures, improves the safety and stability of the product, and may increase its antioxidant capacity. Moreover, fermentation metabolites may synergistically enhance probiotic health benefits. On the other hand, the inoculation of probiotics without fermentation allows for synbiotic beverages with milder changes in terms of physicochemical and sensory attributes.

Polyphenolic composition and antioxidant potential of underutilized Himalayan wild edible berries by high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry

The Himalayan wild berries Myrica esculenta, Duchesnea indica, Prunus cerasoides, and Berberis lycium were studied for the first time for polyphenolic compositions using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry. The chemical analysis of extracts resulted in the identification of 69 polyphenols, including 11 anthocyanins, 28 phenolic acids, 19 flavanoids, 10 ellagitannins, and 1 dihydrochalcone. The caffeoylquinic acids, quercetin, kaempferol, and cyanidin are the common moieties in studied wild berries. In addition, seven phenolic compounds, that is, gallic acid, vanillic acid, caffeic acid, rutin, ferulic acid, quercetin, and myricetin were quantified. Among anthocyanins, cyanidin-3-O-glucoside was the majorly quantified anthocyanin that ranged from 2.52 to 6.18% followed by delphinidin-3-O-glucoside (0.6%-5.53%). The samples were assessed for total phenolics, total anthocyanin content, and antioxidant potential. The results showed that M. esculenta and B. lycium had the highest total phenolic and anthocyanin content and exhibited promising antioxidant activity with IC₅₀ of 32.100 ± 0.42 and 48.44 ± 0.46 μg/mL, respectively. Principal component analysis was able to clearly differentiate between four underutilized Himalayan wild edible berries. The wide variability of polyphenolic constituents supports the consumption of these berries not only to achieve the nutrient requirements among local people but also as promising sources of antioxidants for the food industry.

Systematic evaluation of bioactive components and antioxidant capacity of some new and common bayberry cultivars using an in vitro gastrointestinal digestion method

This study was aimed to investigate the impact of in vitro gastrointestinal digestion on some common and new bayberry cultivars. The contents of total phenolics (246-669mg gallic acid equivalents/kg FW (fresh weight)), flavonoids (116-689mg quercetin-3-O-rutinoside equivalents/kg FW), procyanidins (28-133mg catechin equivalents/kg FW) and anthocyanins (1-7mg cyaniding-3-O-glucoside equivalents/kg FW) were detected in digested cultivars. HPLC-TOF-MS analysis identified 17 phenolic compounds in digested sample. Among all digested cultivars, the new cultivars Anhaizaomei (ABTS, IC₅₀=2.95mg/mL; FRAP, 401.32mg vitamin C equivalents (VCE)/kg FW) and Yingsi (ABTS, IC₅₀=3.28mg/mL; FRAP, 400.81mg VCE/kg FW) showed better in vitro antioxidant capacity. Further cellular assay indicated that the common cultivar Dongkui (2mg/mL) possessed the strongest ROS scavenging activity. The comprehensive evaluation of bioactive components and antioxidant properties using principal component analysis suggests that common cultivar Dongkui, new cultivars Yingsi and Anhaizaomei could be considered as dietary supplements.

Cyanidin-3-O-glucoside: Physical-Chemistry, Foodomics and Health Effects

Anthocyanins (ACNs) are plant secondary metabolites from the flavonoid family. Red to blue fruits are major dietary sources of ACNs (up to 1 g/100 g FW), being cyanidin-3-O-glucoside (Cy3G) one of the most widely distributed. Cy3G confers a red hue to fruits, but its content in raspberries and strawberries is low. It has a good radical scavenging capacity (RSC) against superoxide but not hydroxyl radicals, and its oxidative potential is pH-dependent (58 mV/pH unit). After intake, Cy3G can be metabolized (phases I, II) by oral epithelial cells, absorbed by the gastric epithelium (1%-10%) and it is gut-transformed (phase II &amp; microbial metabolism), reaching the bloodstream (<1%) and urine (about 0.02%) in low amounts. In humans and Caco-2 cells, Cy3G's major metabolites are protocatechuic acid and phloroglucinaldehyde which are also subjected to entero-hepatic recycling, although caffeic acid and peonidin-3-glucoside seem to be strictly produced in the large bowel and renal tissues. Solid evidence supports Cy3G's bioactivity as DNA-RSC, gastro protective, anti-inflammatory, anti-thrombotic chemo-preventive and as an epigenetic factor, exerting protection against Helicobacter pylori infection, age-related diseases, type 2 diabetes, cardiovascular disease, metabolic syndrome and oral cancer. Most relevant mechanisms include RSC, epigenetic action, competitive protein-binding and enzyme inhibition. These and other novel aspects on Cy3G's physical-chemistry, foodomics, and health effects are discussed.

Optimization of the ultrasound-assisted extraction of anthocyanins and total phenolic compounds in mulberry (Morus nigra) pulp

New ultrasound-assisted extraction methods for the determination of anthocyanins and total phenolic compounds present in mulberries have been developed. Several extraction variables, including methanol composition (50-100%), temperature (10-70°C), ultrasound amplitude (30-70%), cycle (0.2-0.7s), solvent pH (3-7) and solvent-solid ratio (10:1.5-20:1.5) were optimized. A Box-Behnken design in conjunction with a response surface methodology was employed to optimize the conditions for the maximum response based on 54 different experiments. Two response variables were considered: total anthocyanins and total phenolic compounds. Extraction temperature and solvent composition were found to be the most influential parameters for anthocyanins (48°C and 76%) and phenolic compounds (64°C and 61%). The developed methods showed high reproducibility and repeatability (RSD<5%). Finally, the new methods were successfully applied to real samples in order to investigate the presence of anthocyanins and total phenolic compounds in several mulberry jams.

Development and validation of a liquid chromatography method for anthocyanins in strawberry (Fragaria spp.) and complementary studies on stability, kinetics and antioxidant power

A RPLC-DAD method for the analysis of eight anthocyanins was developed, validated and applied to strawberry extracts. The chromatographic method was conducted under gradient elution in acidulated water-methanol mobile phase and octadecyl-silica columns. An ultrasound extraction procedure was optimized by a 3(2) factorial design (%HCl in methanol, temperature, and time) and response surface methodology. Method validation was performed according to the following parameters: linearity (R(2)>0.99, p-value<10(-4), F>725), LOD (3-7 μmol L(-1)) and LOQ (9-22 μmol L(-1)), selectivity/specificity (baseline separation of all analytes and peak purity), instrumental precision (<6.4%CV), repeatability (<6.3%CV) and intermediate precision (<9.9%CV), recovery (83-99%), robustness (mobile phase pH, column temperature and flow rate) and stability (high temperatures and storage; 1st order kinetics). The antioxidant power of anthocyanins was measured on-line (ABTS(+) reaction; Trolox as reference). Ten strawberry extracts were quantified (average values: 24.2 μg/g for cyanidin-3-glucoside and 49.1 μg/g for pelargonidin-3-glucoside).