Estimation of the kinetic parameters of anthocyanins degradation at different water activities during treatments at high temperature (100–140 °C) using an unsteady-state 3D model

Effect of Purple Sweet Potato Using Different Cooking Methods on Cytoprotection against Ethanol-Induced Oxidative Damage through Nrf2 Activation in HepG2 Cells

The aim of this study was to investigate the effects of different cooking methods on the hepatoprotective effects of purple sweet potatoes against alcohol-induced damage in HepG2 cells. Purple sweet potatoes (Ipomeoea batatas L. Danjami) were subjected to different cooking methods, including steaming, roasting, and microwaving. Steaming resulted in a higher cytoprotective effect against alcohol damage than the other cooking methods. Additionally, the highest inhibition of glutathione depletion and production of reactive oxygen species against alcohol-induced stress were observed in raw and/or steamed purple sweet potatoes. Compared to roasted and/or microwaved samples, steamed samples significantly increased the expression of NADPH quinone oxidoreductase 1, heme oxygenase 1, and gamma glutamate-cysteine ligase in alcohol-stimulated HepG2 cells via the activation of nuclear factor erythroid 2-related factor 2. Moreover, ten anthocyanins were detected in the raw samples, whereas five, two, and two anthocyanins were found in the steamed, roasted, and microwaved samples, respectively. Taken together, steaming purple sweet potatoes could be an effective cooking method to protect hepatocytes against alcohol consumption. These results provide useful information for improving the bioactive properties of purple sweet potatoes using different cooking methods.

A Novel Ultrasound-Assisted Extraction Method for the Analysis of Anthocyanins in Potatoes (Solanum tuberosum L.)

Purple potato is one of the least known and consumed potato varieties. It is as rich in nutrients, amino acids and starches as the rest of the potato varieties, but it also exhibits a high content of anthocyanins, which confer it with some attractive health-related properties, such as antioxidant, pain-relieving, anti-inflammatory and other promising properties regarding the treatment of certain diseases. A novel methodology based on ultrasound-assisted extraction has been optimized to achieve greater yields of anthocyanins. Optimal extraction values have been established at 70 °C using 20 mL of a 60% MeOH:H₂O solution, with a pH of 2.90 and a 0.5 s⁻¹ cycle length at 70% of the maximum amplitude for 15 min. The repeatability and intermediate precision of the extraction method have been proven by its relative standard deviation (RSD) below 5%. The method has been tested on Vitelotte, Double Fun, Highland and Violet Queen potatoes and has demonstrated its suitability for the extraction and quantification of the anthocyanins found in these potato varieties, which exhibit notable content differences. Finally, the antioxidant capacity of these potato varieties has been determined by means of 2,2-diphenyl-1-picrylhydrazyl (DDPH) radical scavenging and the values obtained were similar to those previously reported in the literature.

Comparison between airborne ultrasound and contact ultrasound to intensify air drying of blackberry: Heat and mass transfer simulation, energy consumption and quality evaluation

This study aimed at investigating the performances of air drying of blackberries assisted by airborne ultrasound and contact ultrasound. The drying experiments were conducted in a self-designed dryer coupled with a 20-kHz ultrasound probe. A numerical model for unsteady heat and mass transfer considering temperature dependent diffusivity, shrinkage pattern and input ultrasonic energies were applied to explore the drying mechanism, while the energy consumption and quality were analyzed experimentally. Generally, both airborne ultrasound and contact ultrasound accelerated the drying process, reduced the energy consumption and enhanced the retentions of blackberry anthocyanins and organic acids in comparison to air drying alone. At the same input ultrasound intensity level, blackberries received more ultrasound energies under contact sonication (0.299 W) than airborne sonication (0.245 W), thus avoiding the attenuation of ultrasonic energies by air. The modeling results revealed that contact ultrasound was more capable than airborne ultrasound to intensify the inner moisture diffusion and heat conduction, as well as surface exchange of heat and moisture with air. During air drying, contact ultrasound treatment eliminated the gradients of temperature and moisture inside blackberry easier than airborne ultrasound, leading to more homogenous distributions. Moreover, the total energy consumption under air drying with contact ultrasound assistance was 27.0% lower than that with airborne ultrasound assistance. Besides, blackberries dehydrated by contact ultrasound contained more anthocyanins and organic acids than those dried by airborne ultrasound, implying a higher quality. Overall, direct contact sonication can well benefit blackberry drying in both energy and quality aspects.

Ultrasound-assisted enzymatic extraction of anthocyanins from grape skins: optimization, identification, and antitumor activity

Grape skins produced during the grape juice production and processing contain abundant anthocyanins and other active compounds. Consequently, this study optimized the extraction conditions for ultrasound-assisted enzymatic extraction (UAEE) of anthocyanins from grape skins via response surface methodology coupled with genetic algorithm. The optimum extraction parameters to achieve the highest anthocyanins yield (3.01 ± 0.04) mg/g from grape skins by UAEE were obtained under an extraction temperature of 50 °C, ultrasonic power of 400 W, pectinase dosage of 0.16%, and extraction time of 28 min. The AB-8 macroporous resin combined Sephadex LH-20 techniques were further employed to purify the anthocyanins extracts obtained under optimum extraction conditions (AEOEC), and the main anthocyanins were identified using high-performance liquid chromatography tandem mass spectrometry. The purified anthocyanins contained two anthocyanins in terms of delphinidin-3,5-O-diglucoside and cyanidin-3-O-rutinoside with purity of 91.35% and 92.64%, respectively. Ultimately, we further evaluated the antitumor activity of AEOEC and two purified anthocyanins on breast cancer. The results indicated that the antitumor effect of AEOEC on breast cancer MCF-7 cells was better than that of two purified anthocyanins. In addition, AEOEC could memorably increase intracellular reactive oxygen species levels and apoptosis of MCF-7 cells, and arrest MCF-7 cells in the G2/M phases. The findings provide an effective and feasible method for anthocyanins extraction and reduce the environmental burden of this waste.

Optimization Ultrasound-Assisted Deep Eutectic Solvent Extraction of Anthocyanins from Raspberry Using Response Surface Methodology Coupled with Genetic Algorithm

Raspberries have been reported to contain abundant anthocyanins and other active compounds. To extract anthocyanins from raspberries more efficiently, a novel procedure of ultrasound-assisted deep eutectic solvent extraction (UADESE) was proposed in this paper. The extraction process was optimized by response surface methodology coupled with a genetic algorithm. The optimum extraction parameters to achieve the highest yield of anthocyanins 1.378 ± 0.009 mg/g from raspberry powder via UADESE were obtained at a water content of 29%, ultrasonic power of 210 W, extraction temperature of 51 °C and extraction time of 32 min. The AB-8 macroporous resin combined with the high-speed counter current chromatography (HSCCC) method were further used to isolate and purify the anthocyanins extracts obtained under optimum extraction conditions, and the structure of purified anthocyanins components were identified by UV-Visible spectrophotometer (UV-Vis), high-performance liquid chromatography (HPLC), high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS/MS), ¹H nuclear magnetic resonance (NMR) and ¹³C-NMR spectra. The two anthocyanins (cyanidin-3-glucoside with a purity of 92.25% and cyanidin-3-rutinoside with a purity of 93.07%) identified were consistent with those present in raspberries. These findings provided an effective and feasible method for extraction, isolation and purification of anthocyanins from natural plant resources.