Search

Interest in the processing and application of natural anthocyanin pigments is intensifying. In this work, we developed a protocol for obtaining anthocyanins from wild Asian bird berries (Prunus nepalensis L.) using ultrasound‐assisted extraction (UAE) and response surface methodology. The chemical profile, antioxidant activity, and co‐pigmentation of the anthocyanin extract were also investigated. The results showed that the maximum anthocyanin yield was achieved under optimal conditions of 60°C, 300 W ultrasonic power, and 30 min ultrasonic time. Using UHPLC‐ESI‐MS2 analysis, two major anthocyanins and 19 other phenolics were identified in the anthocyanin extract, which displayed significant antioxidant potential in vitro. In addition, the color stability of the anthocyanin extract was thermodynamically improved by phenolic acids and organic acids where oxalic acid was the most effective co‐pigment. These results revealed that Asian bird berries anthocyanins could be effectively recovered by UAE, and further stabilized by co‐pigments. Novelty impact statement: The chemical instability of anthocyanins poses a significant challenge for their preparation and implementation as food colorants. In this study, the anthocyanins obtained from P. nepalensis L. fruits were modulated, for the first time, with the help of co‐pigments such as oxalic acid, citric acid, ascorbic acid, gallic acid, tannic acid, and pyrogallic acid. These results could open up the possibility of large‐scale applications of anthocyanins sourced from many uncultivated plants. [ABSTRACT FROM AUTHOR]

Glycoproteins are closely linked to the occurrence and development of many diseases. Therefore, it is of great importance to develop highly selective, sensitive, efficient detection methods for glycoproteins. To overcome the problems with traditional detections methods, such as mass spectrometry, chromatography-mass spectrometry, and enzyme-linked immunosorbent assay, boronate affinity material (BAM)-based sensors have developed rapidly for the specific recognition and detection of glycoproteins because of the advantages of pH-controlled binding/release, reversibility of the reaction, high specificity, and high selectivity, showing their wide application prospects. In recent years, there have been many significant leaps in the use of BAMs for sensing and detecting glycoproteins, but there are still many challenges and room for development. Therefore, this review critically investigates and summarizes recent advances with BAM-based sensors for glycoprotein detection. We focus on the common boronate affinity ligands of BAMs and their grafting methods, functional materials utilized in the synthesis of BAM-based sensors, advanced technologies, and applications. Finally, we propose the remaining challenges and future perspectives to accelerate the development of BAMs, and to utilize it for further developing versatile BAMs with a variety of promising applications. [ABSTRACT FROM AUTHOR]

The present study aimed to compare the chemical and antioxidant differences between the extractable and non‐extractable polyphenols (EPP and NEPP) in commercial teas with different fermentation degrees. The results showed that both content and antioxidant activity of NEPP were lower than EPP regardless of fermentation degrees of teas. One white tea, Baekho Silver Needle (BSN), had the highest NEPP content (58.38 ± 0.73 mg GAE/g DW) by alkaline hydrolysis, as well as the antioxidant activities among different teas studied. Meanwhile, alkaline hydrolysis also was the most effective method in extracting the NEPP from these teas, followed by acid and enzymatic hydrolysis. Combined principle component analysis and hierarchical clustering analysis demonstrated that gallic acid (GA), epigallocatechin (EGC), and gallocatechin (GC) were three major components in the NEEP studied, with the highest content 13.89 ± 0.87 mg/g DW in BSN, 16.14 ± 1.24 mg/g DW in Dianhong (DH), and 7.26 ± 0.55 mg/g DW in Biluochun (BLC), respectively. GA also was found to be the main contributor to antioxidant activity of NEPP. In addition, NEPP with different fermentation degrees showed discriminations in total polyphenols content, phytochemical profiles, and antioxidant activities but were disorder with the fermentation degrees of these teas. These results provided more information for NEPP in teas with different fermentation degrees including the phytochemical profiles and optimal extraction method. Practical applications: NEPP have long been underestimated or neglected because this part of polyphenolic fraction cannot be extracted from the residues by aqueous or organic solvents. This study systematically investigated phytochemical profiles and antioxidant activity of EPP and NEPP in commercial teas with different fermentation degrees. Comparing the release efficacy of tea NEPP by different extraction methods indicated that tea residues were still a considerable source for NEPP. Profiles of polyphenols in teas with different fermentation degrees can be better uncovered according to this study to improve the health. [ABSTRACT FROM AUTHOR]

The article focused on the Cretaceous evolution of Northeast China, including the 973 Scientific exploration Well Work program. Topic include ZK2-3, is an andesite collected from 45°34′25.09″N, 131°20′5.46″E, at 786.54 m within the ZK2 well, eastern Boli Basin, China; and involve Ren et al (2005) and Li et al (2006) inferred an age of 107.1–101.7 Ma, based on biostratigraphy, paleomagnetic data and sequence stratigraphy.

BACKGROUND Sand rice (Agriophyllum squarrosum) is an underutilized pseudocereal bearing edible seeds. In this study, the phenolics and antioxidant activity of sand rice seeds after cooking and in vitro digestion were extensively investigated. RESULTS: Total phenolic content (TPC) of the sand rice seeds was slightly increased whereas total flavonoid content (TFC) decreased after boiling. Furthermore, nine compounds were detected in the uncooked seeds, with hyperoside (169.19 ± 6.59 µg g−1 dry weight (DW)), protocatechuic acid (167.46 ± 7.21 µg g−1 DW), and rutin (83.15 ± 3.26 µg g−1 DW) as the major components. Apart from the bioaccessible phenolics in the aqueous fraction, these compounds retained in the solid residue of the porridge were released to varying degrees during simulated digestion. In addition, these phenolic extracts also exerted considerable antioxidant potency, which was positively correlated with their corresponding TPC, TFC, and phenolic profiles. CONCLUSION: These results indicated that both boiling and in vitro digestive treatments could considerably enhance the release of bioactive compounds and thus contribute antioxidant properties to sand rice porridge. These findings suggest that sand rice seed is a potential functional food and an excellent natural antioxidant source. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Copyright of CyTA: Journal of Food is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this study was to select an appropriate drying technique from air-impingement jet drying (AIJD), hot air drying (HAD) and microwave drying (MWD) which can be combined with freeze drying (FD). Results showed that AIJD with relatively high efficiency, low energy consumption and good drying quality was suitable to be combined with FD. To further improve the drying technology of kiwifruits, the energy consumption and quality of dried kiwifruit with different conversion point during combined FD and AIJD were also tested. The energy consumption obtained for AIJD+FD and FD+AIJD was lower than that obtained for FD alone. Among the products, the kiwifruit processed by AIJD+FD not only showed better attractive green colour and higher sweetness perception, but also revealed higher rehydration ratio than FD and FD+AIJD kiwifruits, which was positively related to microstructure changes. The best AIJD+FD process, from nutrient retention and antioxidant activity considerations, was the combination of 65 min AIJD pre-drying and FD finish drying. Therefore, AIJD pre-drying and FD finish drying as a promising way with short drying time and strong nutrient retention capacity may be applied to the drying processing of agricultural products. [ABSTRACT FROM AUTHOR]

This study aimed to optimize trienzyme-assisted extraction (EAE) conditions for total polyphenols (TP) from Ulmus pumila barks (UPB). Response surface methodology (RSM) was used to optimize EAE conditions including pH, temperature, and time. The extraction efficiency of three extraction procedures on the TP yield, antioxidant activities and chemical composition of UPB extracts was also compared and characterized. Our results showed that the maximum extraction yield of TP was 16.04 ± 0.38 mg gallic acid equivalents/g dry weight (GAE/g DW) under the optimum EAE conditions (pH = 4.63, 52.6 °C and 62 min). Meanwhile, the EAE gave a higher extraction yield of TP and then a greater in vitro antioxidant capacity compared with those obtained from both ultrasound-assisted extraction (UAE) and conventional heat extraction (CHE). In addition, seven polyphenolic compounds were validated by high-performance liquid chromatography analysis in the extracts at the optimized conditions. The results of this study further confirmed that EAE could be explored as a state-of-the-art environmentally friendly technology for recovering optimum amounts of antioxidant polyphenols from plant sources. [ABSTRACT FROM AUTHOR]

Neutral-point (NP)-clamped three-level inverter, which is a widely used topology of multilevel converters, suffers from the NP voltage drift as its main technical drawback. The nearest-three-virtual-vector (\NTV^2) modulation method can control the NP voltage balance for any load over the full range of inverter output voltage. However, compared with the nearest-three-vector (NTV) modulation method, \NTV^2 increases the switching frequency. This paper combines \NTV^2 with NTV, and the two methods are used alternately in a fundamental cycle. The duty-cycle coefficients of the redundant small vectors are analyzed to explore the intervals where NTV can control the NP voltage balance in a fundamental cycle. The proportional parameter, which represents the combination of the two methods in hybrid space vector pulsewidth modulation, can be selected to achieve a high-performance NP balance control and low switching frequency. The steady- and transient-state behaviors of the proposed strategy are analyzed in this paper. The experimental results verify the validity of the proposed strategy. [ABSTRACT FROM PUBLISHER]

The ongoing expansion of mushroom industries has generated enormous spent mushroom substrate with the potential for production of valuable chemicals. This study aimed to investigate ultrasound‐assisted extraction (UAE) of fungal sterols from spent shiitake (Lentinula edodes) substrate (SSS) by response surface methodology. The results showed that three variables, including ultrasonic power, extraction time, and liquid–solid ratio, had considerable influence on the extraction efficiency of total fungal sterols with liquid–solid ratio being highly significant for the process. The optimal UAE conditions included liquid–solid ratio 22 mL/g, ultrasonic power 432 W, and extraction time 16 min for the maximum recovery of fungal sterols (151.62 mg ergosterol equivalents/100 g dry weight) from SSS. Further GC‐MS analysis indicated that the extracts yielded under the optimal conditions contained ergosterol, ergosta‐7,22‐dienol, and β‐sitosterol, in which ergosterol was the most abundant mycosterol. The extracts also showed a comparable antitumor effect against three cancer cell lines. Practical applications: Spent mushroom substrate, a major by‐product of mushroom industries, remains a big challenge for the profitability of mushroom industries. Our results indicated that spent shiitake substrate can be valorized by UAE for production of fungal sterols. [ABSTRACT FROM AUTHOR]

Lentinus edodes is the second-most popular and cultivated mushroom worldwide due to its nutritional and health-promoting benefit. However, the mushroom production generates vast amounts of spent L. edodes substrate (SLS) that is generally discharged into the environment, posing a great challenge within mushroom by-product valorization. In this work, SLS polysaccharide (SP) was ultrasonically extracted by optimizing the process conditions with response surface methodology. Using gradient ethanol precipitation, SP was separated into SP40, SP60 and SP80, and their monosaccharide composition, structural properties, and antioxidant potential were further characterized and compared. The results showed the total polysaccharide content reached up to 37.05 ± 0.31 mg/g under the optimal conditions including an extraction temperature of 50 °C, a liquid-solid ratio of 30 mL/g and an ultrasonic power of 120 W. SP and its fractional precipitations were heteropolysaccharides sharing a similar monosaccharide composition including L-rhamnose, D-glucuronic acid, D-galacturonic acid, d -glucose and D-xylose, and a typical infrared spectrum for polysaccharide. These fractions also varied in the surface morphology, where SP80 was looser and more porous than SP40 and SP60. Furthermore, SP and SP80 displayed the strongest antioxidant activities in vitro. This study identified a novel and practical strategy to valorize SLS for valuable polysaccharide. • The UAE extraction of SLS polysaccharides were optimized by RSM. • The structural features of SLS polysaccharides were determined by SEM, FT-IR and HPLC. • The polysaccharides were rhamnose polymers with considerable antioxidant activities. • SLS represents an untapped source of biological polysaccharides. [ABSTRACT FROM AUTHOR]

The present study explored the changes in phytochemical profiles (proximate, amino acids, fatty acids, and lignans) and antioxidant activity of Schisandra sphenathera fruit with three maturity stages (un-ripen, semi-ripen and fully-ripen). The results showed that the whole fruit contained high levels of essential amino acids and unsaturated fatty acids (linoleic and oleic acids), whose content slightly reduced with maturity. Meanwhile, the contents of total phenolics, total flavonoids, and total tannins were generally decreased in the extractable, free, conjugated, and bound phenolic fractions, while the total anthocyanin content in these phenolic fractions were increased during ripening. Furthermore, the lignan profiling of these fractions indicated an increased content of schisandrol A and gomisin J, but a decreased content of schisandrin B and schisandrin C in the extractable phenolic fractions during fruit maturation. It was noted that schisantherin B and schisandrin A were recorded in all phenolic fractions, alongside schisandrin B and schisandrin C detected only in extractable form. Additionally, the extractable phenolic fractions exerted considerable antioxidant activity with little or low significance at three maturity stages. Therefore, the whole fruit of S. sphenathera abound with unsaturated fatty acids and antioxidant lignans, boosting its chances of being fully utilized as a versatile and economical crop in pharmaceutical and food industries for different purposes. • S. sphenathera fruit contained high levels of essential amino acids and unsaturated fatty acids. • Both extractable and non-extractable phenolics changed with ripening stages. • Lignan profiles of different phenolics fractions were also varied. • Schisantherin B and schisandrin A presented in free, conjugated and bound forms. [ABSTRACT FROM AUTHOR]

Current research for the first time demonstrated that endothelial dysfunction and hepatic injury in mice were induced by ingestion of 3% l -carnitine water for consecutive 10 weeks. Interestingly, oral administration of dietary raffinose family oligosaccharides (RFOs) at 400 and 800 mg/kg bw significantly reduced the impact of l -carnitine on the serum total cholesterol, triglycerides, high- and low-density lipoproteins, alanine aminotransferase, aspartate amino-transferase, NO, endothelin-1 and C-reactive protein. Furthermore, l -carnitine-induced elevation of hepatic lipid contents and malonaldehyde formation, and the inhibition of SOD and GSH-P x activities in mice were markedly ameliorated by oral administration of RFOs. Moreover, histopathology of H&E and Oil Red O staining of the liver also confirmed the protective effect of RFOs against hepatic steatosis and oxidative injury induced by high l -carnitine diet in mice. These findings for the first time suggest that RFOs may alleviate endothelial dysfunction and liver injury from ingestion of high l -carnitine diet. [ABSTRACT FROM AUTHOR]

This study was designed to elucidate the colon microbiota-targeted release of nonextractable bound polyphenols (NEPs) derived from Fu brick tea and to further identify the possible anti-inflammatory mechanism in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice. 1.5% DSS drinking water-induced C57BL/6J mice were fed rodent chow supplemented with or without 8% NEPs or dietary fibers (DFs) for 37 days. The bound p -hydroxybenzoic acid and quercetin in NEPs were liberated up to 590.5 ± 70.6 and 470.5 ± 51.6 mg/g by in vitro human gut microbiota-simulated fermentation, and released into the colon of the mice supplemented with NEPs by 4.4- and 1.5-fold higher than that of the mice supplemented without NEPs, respectively ( p < 0.05). Supplementation with NEPs also enhanced the colonic microbiota-dependent production of SCFAs in vitro and in vivo ( p < 0.05). Interestingly, Ingestion of NEPs in DSS-induced mice altered the gut microbiota composition, reflected by a dramatic increase in the relative abundance of Dubosiella and Enterorhabdus and a decrease in the relative abundance of Alistipes and Romboutsia ( p < 0.05). Consumption of NEPs was demonstrated to be more effective in alleviating colonic inflammation and UC symptoms than DFs alone in DSS-treated mice ( p < 0.05), in which the protective effects of NEPs against UC were highly correlated with the reconstruction of the gut microbiome, formation of SCFAs, and release of bound polyphenols. These findings suggest that NEPs as macromolecular carriers exhibit targeted delivery of bound polyphenols into the mouse colon to regulate gut microbiota and alleviate inflammation.

Quercetin (Que) has consistently been reported to be useful cytotoxic compound in vivo and in vitro, but little is known on its metabolites. Here, we examined and compared the cytotoxic effects of Que and its water-soluble metabolites, isorhamnetin (IS) and isorhamnetin-3-glucuronide (I3G), in human breast-cancer MCF-7 cells to uncover their tumor-inhibitory mechanisms and structure-function relationships. The results showed that Que, IS, and I3G could dose-dependently inhibit the growth of MCF-7 cells, and the cytotoxic effect was ranked as Que > IS > I3G. Furthermore, Que, IS, and I3G mediated cell-cycle arrest principally in S phase, followed by a decrease in the number of cells in G0/G1 and G2/M; moreover, 70.8, 68.9, and 49.8% of MCF-7 tumor cells entered early-phase apoptosis when treated with 100 μM Que, IS, and I3G for 48 h, respectively. Moreover, induction of apoptosis by Que, IS, and I3G was accompanied by the marginal generation of intracellular reactive oxygen species (ROS). Given these results, Que, IS, and I3G possess strong cytotoxic effects through an ROS-dependent apoptosis pathway in MCF-7 cells.