Search

Here, we examined the phytochemical profiles, antioxidant activity (AA), and antiproliferative activity (APA) of four Chinese bayberry (Myrica rubra Sieb. et Zucc.) pulp extracts. They were found to be rich in total phenolics content (TPC; 186.45 ± 5.42 to 498.94 ± 8.25 mg of gallic acid equiv./100 g FW) and total flavonoids content (TFC; 126.28 ± 4.18 to 194.35 ± 12.03 mg of catechin equiv./100 g FW). For all varieties, the free flavonoid/phenolic/anthocyanin contents were higher than that the bound fractions. Wild pink bayberry (WPB) displayed the highest values of TPC and TFC, and also showed the highest total antioxidant activity (TAA) as revealed by peroxyl radical scavenging capacity (PSC) (451.47 ± 8.01 µmol Vit. C equiv./100 g FW), and free cellular antioxidant activity (CAA) (184.99 ± 6.11 µmol quercetin equiv./100 g FW, no PBS wash; 117.78 ± 2.34 µmol quercetin equiv./100 g FW, PBS wash) assays. Bayberry extracts had a marked reduction in the APA of HepG2 cells, and WPB exhibited the lowest EC50 (8.50 ± 0.83 mg/ml) value, which was probably associated with cell cycle arrest and apoptosis induction. Practical Application: Chinese bayberry (Myrica rubra Sieb. et Zucc.) fruit is rich in natural phenolic compounds, which might be a functional ingredient in food and nutraceutical products. Our findings would provide a logical strategy to promote the comprehensive utilization of phenolics in bayberry fruit with both health and economy benefits. [ABSTRACT FROM AUTHOR]

Phenolics, antioxidant activities, and antiproliferative properties of brown Hypsizygus marmoreus (brown HM) and white Hypsizygus marmoreus (white HM) were compared. The results showed that the contents of (+)‐catechin, gallic acid, and protocatechuic acid of brown HM were higher than those of white HM. Moreover, brown HM had greater cellular antioxidant activity (CAA), peroxyl radical scavenging capacity (PSC), and oxygen radical absorbance capacity (ORAC) values than white HM, which demonstrated that brown HM presented a stronger antioxidant capacity. Both of brown HM and white HM showed remarkable antiproliferative activities against HepG2 cells and brown HM was proven to be the more effective. The flow cytometry results revealed that both of brown HM and white HM could induce G1 arrest and cell apoptotics in a dose‐dependent manner. In addition, CyclinD1, CDK4, and Bcl‐2 mRNA expression levels were downregulated with the treatment of brown HM or white HM. Taken together, our study revealed that brown HM afforded better antioxidant and antiproliferative activities than white HM and laid the foundation for potential application of Hypsizygus marmoreus as source of nutraceuticals and functional food products. Practical Application: A systematic assessment of the potential differences of phenolics, antioxidant, and antiproliferative activities between different Hypsizygus marmoreus varieties was carried out in the present study. Furthermore, our findings would present possible antiproliferative mechanism of extracts of different Hypsizygus marmoreus varieties, which may provide theoretical basis for further development and utilization of Hypsizygus marmoreus. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the antioxidant activity and the homology of peptides extracted from dry-cured Xuanwei and Jinhua ham. The antioxidant activity of crude peptides was assessed by ORAC and ABTS assays and the scavenging effects on DPPH and O 2− free radicals. LC-ESI-Q-TOF-MS/MS was used to analyze the peptide composition. Based on the identified peptides, homologous proteins were matched by the Peaks software. Overall, 243 and 213 peptides were identified with their parent proteins in Xuanwei and Jinhua dry-cured hams. Based on the ORAC and TEAC values, XHP showed higher antioxidant ability than JHP ( P  < 0.05). After further purification by G-15 chromatography, the results indicate that the oligopeptides with less than 1000 Da had greater antioxidant activity than the other two fractions. Homology-based proteomics showed that the majority of peptides originated from myosin which accounted for 26% in XHP and 32% in JHP respectively. [ABSTRACT FROM AUTHOR]

Summary: Asp‐Leu‐Glu‐Glu (DLEE) is one of the antioxidant peptides purified from Chinese dry‐cured Xuanwei ham in our previous study. In the current work, the stability in a simulated digestion system, the transportation pathway and the antioxidant ability of DLEE were further investigated in a Caco‐2 cell monolayer. In the simulated gastrointestinal digestion system, no oligopeptides were generated. In the transport trial, the inhibitors cytochalasin D increased the transport of DLEE across the Caco‐2 cell monolayer, with Papp values of 3.22 × 10−6 cm s−1. A decreased expression occludin was observed with the DLEE incubation in the cell monolayer, and the antioxidant activity showed to be increased gradually in basolateral side. This study indicates that the absorption of DLEE could mainly occur via paracellular transport and provides information about its antioxidant activity after being absorbed across a cell monolayer. [ABSTRACT FROM AUTHOR]

Flaxseed (Linum usitatissimum L.) is well known for its health benefits and chemical composition. This study aimed to evaluate the dynamic changes caused by germination in vitamin C, phenolic compounds and antioxidant activities of flaxseed. It was observed that eight-day germination of flaxseed sprouts caused increases in phytochemical contents, that is 22.1-fold increase in vitamin C, 2.67-fold increase in phenolics and 5.48-fold increase in flavonoid contents as compare to initial concentration in flaxseeds on dry weight basis. The stimulation was also noted in the three identified phenolic acid ingredients including caffeic acid, p-coumaric acid and ferulic acid. Similarly, the total PSC and ORAC values of flax sprouts at day 8 increased by 3- to 4-folds compared to nongerminated flaxseeds. It is revealed that comparatively, 8-day germination of flax sprouts leads to a significant increase in vitamin C, phenolic constituents and total antioxidant activities than those of flaxseeds. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to study the dynamic changes of ascorbic acid, tocopherols and their antioxidant activity of soya bean sprouts during germination. Results showed that the expression levels of genes related to biosynthesis of ascorbic acid and tocopherols dramatically increased during germination. The expression levels of most genes were up to the peak at day 3 and kept constantly until the end of germination. The contents of ascorbic acid, α-tocopherol, γ-tocopherol, δ-tocopherol and total tocopherols increased during soya bean sprouts germination and reached peak levels on day 5, of 74.42 ± 1.64 mg/100 g DW, 7.64 ± 0.13 mg/100 g DW, 15.84 ± 1.85 mg/100 g DW, 12.37 ± 1.06 mg/100 g DW, 35.85 ± 2.81 mg/100 g DW, respectively. The antioxidant activity of soya bean sprouts increased during germination and reached peak level on day 5 to 311.01 ± 49.01 μmol ASA equiv./100 g DW. Therefore, germination significantly increased the biosynthesis of ascorbic acid, tocopherols and antioxidant activity of soya bean sprouts. [ABSTRACT FROM AUTHOR]

Understanding the influence of processing operations such as drying/dehydration, canning, extrusion, high hydrostatic pressure, pulsed electric field, and ohmic heating on the phytochemicals of fruits, vegetables, and grains is important in retaining the health benefiting properties of these antioxidative compounds in processed food products. Most of the previous investigations in the literature on the antioxidants of fruits, vegetables, and grains have shown that food-processing operations reduced the antioxidants of the processed foods, which is also the usual consumer perception. However, in the last decade some articles in the literature reported that the evaluation of nutritional quality of processed fruits and vegetables not only depend on the quantity of vitamin C but should include analyses of other antioxidant phytochemicals and antioxidant activity. Thermal processing increased the total antioxidant activity of tomato and sweet corn. Most importantly, analysis also depends on the condition, type, and mechanism of antioxidant assays used. This review aims to provide concise information on the influence of various thermal and nonthermal food-processing operations on the stability and kinetics of health beneficial phenolic antioxidants of fruits, vegetables, and grains. [ABSTRACT FROM AUTHOR]

Mactra veneriformishas been used as seafood and traditional Chinese medicine for thousands of years in China. In the present study, hydrolysate was prepared from waste proteins ofM. veneriformisby trypsin treatment. The protective effect of hydrolysate on the defense system against oxidative stress was investigated by estimating the superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in normal mice. The antioxidant activity of hydrolysate was investigated in D-galactose-induced aging mice by estimating the SOD and glutathione peroxidases (GSH-px) activity and MDA level. Amino acid composition and molecular weight distribution were also determined. These investigations suggest that hydrolysate derived from by-products ofM. veneriformispossess antioxidant activity and may be attributed to elevation of the activity of antioxidase and enhanced antioxidant defenses. [ABSTRACT FROM PUBLISHER]

It is evident from various epidemiological studies that consumption of fruits and vegetables is essential to maintain health and in the disease prevention. Present study was designed to examine phenolic contents and antioxidant properties of three varieties of Crataegus pinnatifida (Chinese hawthorn). Shanlihong variety exhibited elevated levels of total phenolics and flavonoid contents, including free and bond phenolics. Procyanidin B 2 was most abundant phenolic compound in all samples, followed by epicatechin, chlorogenic acid, hyperoside, and isoquercitrin. The free ORAC values, and free hydro-PSC values were 398.3–555.8 μmol TE/g DW, and 299.1–370.9 μmol VCE/g DW, respectively. Moreover, the free cellular antioxidant activity (CAA) values were 678–1200 μmol of QE/100 g DW in the no PBS wash protocol, and 345.9–532.9 μmol of QE/100 g DW in the PBS wash protocol. C. pinnatifida fruit could be valuable to promote consumer health. [ABSTRACT FROM AUTHOR]

The phytochemical profiles and antioxidant activity of free, soluble-conjugated, and bound fractions of brown rice and its processed products (textured rice, cooked rice and rice noodle) were studied. Nineteen phenolic acids were identified. Trans -ferulic acid was the most abundant monomeric phenolic acid with trans-trans -8-O-4′ diferulic acid being most abundant diferulic acid. Processing increased the content of free phenolic acids, but decreased the content of soluble-conjugated phenolic acids. The content of bound phenolic acids was increased by improved extrusion cooking technology and cooking, but not affected by rice noodle extrusion. The total phenolic contents and antioxidant activities of free and soluble-conjugated fractions were decreased after processing, whereas those of bound fraction were increased by improved extrusion cooking technology and cooking, but not affected by rice noodle extrusion. Results indicated that whole foods designed for reducing chronic disease risk need to consider the effects of processing on phytochemical profiles and antioxidant activity of whole grains. [ABSTRACT FROM AUTHOR]

The phytochemical content and antioxidant activity of eight varieties of brown rice (BR) are reported. The total phenolic contents of BR ranged from 72.45 to 120.13 mg of gallic acid equiv./100 g. The phenolics from bound fraction contributed 40.6–50.2% of the total phenolic content. The total flavonoid contents of BR ranged from 75.90 to 112.03 mg catechin equiv./100 g. The flavonoids from the bound fraction contributed 26.9–48.2% of total flavonoids. Trans -ferulic acid was the predominant phenolic acid in BR. Total trans -ferulic acid content ranged from 161.42 to 374.81 μg/100 g. The percentage of trans -ferulic acid in bound fraction ranged from 96.4% to 99.2%. Only α- and γ-tocopherols and -tocotrienols were detected in BR with α-tocopherol and γ-tocotrienol being the predominant. The total peroxyl radical scavenging capacity (PSC) of BR ranged from 18.29 to 40.33 mg vitamin C equiv./100 g. The bound fraction contributed 67.2–77.2% of total PSC. [ABSTRACT FROM AUTHOR]

Phytochemical profiles, antioxidant and antiproliferative activities of berry extracts were evaluated and compared in four subspecies of Sea buckthorn ( Hippophaë rhamnoides L.). Among the subspecies, Hippophaë rhamnoides L. subsp. sinensis exhibited highest total phenolics content (38.7 ± 1.3 mg GA equiv./g DW) and corresponding total antioxidant activity. Whereas maximum cellular antioxidant and antiproliferative activities were determined in Hippophaë rhamnoides L. subsp . yunnanensis . Total antioxidant activity was significantly associated to total phenolics, isorhamnetin-3-rutinoside and isorhamnetin-3-glucoside. The cellular antioxidant activity and antiproliferative activity of phytochemicals were fairly correlated to phenolic acids and flavonoid aglycones. Lower median effective dose (EC 50 ) of individual compounds against human liver cancer HepG2 cells proliferation studies confirmed the better correlation between antiproliferative activity of Sea buckthorn extracts and flavonoid aglycones, including isorhamnetin, quercetin and kaempferol. [ABSTRACT FROM AUTHOR]

Citrus is a rich source of nutritive and bioactive compounds. Impact of fruit tissues and ripening stage on phytochemical profile, antioxidant capacity and antiproliferative activity was investigated in Citrus reticulata Blanco cv. Chachiensis (Chachi). Regardless of different ripening stage, peel had the highest contents of phenolics and flavonoids, strongest antioxidant activities resolved by PSC, ORAC and CAA assay and antiproliferative activities against MCF-7, HepG2 and SiHa cancer cell. Increased level of total phenolics, hesperidin and naringin, and elevated antioxidant capacities were detected in peel during maturity, whereas highest amount of nobiletin and strongest antiproliferative activities were explored in immature peel. In flesh the vitamin C content increased during ripening, while lower phenolic content, smallest ORAC value and weakest antiproliferative activity were resolved in mature flesh. The flavonoid content and antioxidant capacity in seed were comparable with flesh and relatively constant during ripening, suggesting seeds as a valuable source of flavonoid extraction for further utilization. The characteristic flavonoids, nobiletin, tangeretin, hesperetin and naringenin inhibited proliferation of SiHa, HepG2 and MCF-7 cell dose-dependently, thus suggesting their contribution and potential application. Results presented here provide the foundation for comprehensive utilization of phytochemicals in different parts of this medicinal and edible citrus fruit. [ABSTRACT FROM AUTHOR]

The polysaccharides from Mactra veneriformis (MVPS) were degraded by controlled mild acid hydrolysis to produce active oligosaccharides. MVPS can easily be hydrolyzed by H 2 SO 4 or HCl. The hydrolyzing process was investigated in acid addition and reaction time by evaluating the producing content of reducing sugar. Hydrolysis with 1 M HCl to MVPS can generate a time-depended behavior that is mild and controllable. HPLC analysis monitored the change of oligosaccharides composition in hydrolyzing. Total nine oligosaccharides are recognizable in the HPLC profile, and their content showed a regular transformation in hydrolysis. Those nine ingredients were identified as glucooligosaccharides with DP from 1 to 7 by MS analysis. Antioxidant activities of the typical hydrolyzates as well as MVPs were further tested in assays of DPPH and hydroxyl radicals scavenging, and reducing power. It was found that HCl hydrolyzate exhibited stronger antioxidant effects than MVPS and H 2 SO 4 hydrolyzate due to its higher content of oligosaccharides. [ABSTRACT FROM AUTHOR]

Single-factor experiment and Box–Behnken design (BBD) were applied to optimize the ultrasound-assisted extraction of mulberry fruits polysaccharides (MFP). Under optimum conditions: ratio of water to raw material 40.25, extraction temperature 69 °C, ultrasonic power 190 W and extraction time 75 min, the MFP yield was 3.13% (±0.07%), in accordance to the predicted value of 3.04%. The mulberry fruits polysaccharides fractions was obtained by deproteinization (MFP-1), followed by decolorization and deionization (MFP-2). Carbohydrate content in MFP, MFP-1 and MFP-2 was 58.61% (±1.47%), 69.98% (±0.91%), 81.18% (±1.29%), as well as proteins was estimated 16.50% (±0.86%), 1.57% (±0.63%), 1.02% (±0.18%), respectively. The FT-IR indicated that MFP, MFP-1 and MFP-2 were acidic polysaccharides. The MFP-1 exhibited the strongest antioxidant activity, while MFP-2 showed the strongest hyperglycemic activity in vitro . This may be caused by their different compositions and physical properties in the different mulberry fruit polysaccharides fractions. [ABSTRACT FROM AUTHOR]

Water-soluble polysaccharides from Prunella vulgaris Linn ( P. vulgaris ) were fractionated using DEAE-Sepharose fast-flow column to obtain several eluents of water (PV-P1), 0.1 M NaCl (PV-P2) and 0.2 M NaCl (PV-P3). Structural analyses showed that PV-P1 had a higher molecular weight and degree of branching as compared to PV-P2 and PV-P3. Tertiary structure analyses indicated that PV-P1, PV-P2 and PV-P3 did not have triple-helical conformation. PV-P2 and PV-P3 showed stronger antioxidant activities than PV-P1, as measured radical scavenging capacities. PV-P1 showed stronger immunomodulatory activities than PV-P2 and PV-P3 in term of stimulation of the production of pro-inflammatory cytokines, including nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in murine macrophage RAW 264.7 cells. PV-P1, PV-P2 and PV-P3 did not exhibit cytotoxicities against RAW 264.7 at the concentrations tested. These results suggest that P. vulgaris polysaccharides could be explored as potential antioxidant and immunomodulatory agents for the complementary medicine or functional foods. [ABSTRACT FROM AUTHOR]

• Quantitative analysis of 21 microbial metabolites of (epi)catechin was performed. • The antioxidant activities of 12 metabolites were evaluated. • C-ring opened significantly increased the antioxidant activities of (epi)catechin. • Dehydroxylation at the C-3′ or C-4′ mostly deprived their antioxidant activity. The changes in DPPH radical-scavenging capability of catechin and epicatechin during 24 h incubation with fecal microbiota in vitro and the targeted analysis of the characteristic metabolites by using UPLC-Q-TOF indicated that increase in antioxidant activity was synchronous with the accumulation of C-ring cleavage metabolites. Therefore, C-ring cleavage metabolite, 1-(3′,4′-Dihydroxyphenyl)-3-(2′′,4′′,6′′-trihydroxyphenyl)propan-2-ol (3,4-DHPP-2-ol), was separated from incubation liquid. The antioxidant activities of this metabolite and other 11 metabolites were examined through DPPH and ABTS free radical scavenging capacity and ferric reducing antioxidant capability (FRAC). The results indicated that all metabolites with the structure of 3′,4′-dihydroxylated had high antioxidant activity, especially 3,4-DHPP-2-ol, whose EC 50 was 5.97 μM in DPPH assay, 2 times as high as that of catechin, and 1.8 times as high as that of epicatechin. But the metabolites with the structure of monohydroxylated or unhydroxylated on the benzene ring hardly exhibited antioxidant activity. [ABSTRACT FROM AUTHOR]