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The antioxidant and aphrodisiac properties of oyster meat (OM) and its hydrolysates by alcalase (OMA) were compared. The results showed that OMA displayed a higher antioxidant activity than OM with or without gastrointestinal digestion. Furthermore, the study reported that oral administration of OM or OMA could induce aphrodisiac activities and consequently enhance the sexual behavior in normal male mice, at a dose of 250 mg/kg. Additionally, OMA also exhibited better antioxidant activity in vivo than OM by improving the activities of the endogenous cellular antioxidant enzymes and decreasing the MDA levels, which may be helpful in improving the sexual function. These results indicated that oysters' could be a potential functional ingredient with antioxidant and aphrodisiac activities, and the activities could be improved by alcalase hydrolysis., (Copyright © 2019. Published by Elsevier Ltd.)

The study aimed at improving the antioxidant activity of β-conglycinin to enhance the oxidative and physical stabilities of safflower oil-in-water emulsion stabilized by β-conglycinin. Heating promoted binding affinity and antioxidant activity of β-conglycinin. Catechin and chlorogenic acid showed higher binding affinities towards unheated (or heated) β-conglycinin than caffeic acid and quercetin. The enhancement efficiencies of the phenolics on the antioxidant activity of unheated (or heated) β-conglycinin decreased in the order of catechin > quercetin > chlorogenic acid > caffeic acid. Hydrophobic force and hydrogen bonding were the important binding forces for the selected phenolics to β-conglycinin. The complexation with catechin has no side effect on interfacial behavior and emulsifying property of β-conglycinin. The use of heated β-conglycinin-catechin complex as an emulsifier for preparing safflower oil emulsion effectively improved the oxidative and physical stabilities of the emulsion treated with lipoxygenase through inhibition of lipid oxidation, protein carbonyl formation and sulfhydryl loss., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The black garlic juice is popular for its nutritive value. Enrichment of antioxidants is needed to make black garlic extract an effective functional ingredient. Five macroporous resins were evaluated for their capacity in adsorbing antioxidants in black garlic juice. XAD-16 resin was chosen for further study due to its high adsorption and desorption ratios. Pseudo-second-order kinetics (q e =625μmol Trolox equiv/g dry resin, k 2 =0.0001463) and Freundlich isotherm models (ΔH=-10.1547kJ/mol) were suitable for describing the whole exothermic and physical adsorption processes of the antioxidants from black garlic juice on XAD-16 resin. The antioxidants and phenolics were mostly enriched in 40% ethanol fraction by XAD-16 resin column chromatography. The black garlic extract and its fractions could protect erythrocytes against AAPH-induced hemolysis in dose-dependent manners. The pretreatment of AAPH-damaged erythrocytes with 40% ethanol fractions (2.5mg/mL) significantly decreased the hemolysis ratios from 53.58% to 3.79%. The 40% ethanol fraction possessing strong intracellular antioxidant activity could be used as a functional food ingredient., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study aimed to explore the potential of polished adlay, brown adlay, adlay bran, and adlay hull to prevent and treat hyperuricemia. Brown adlay extract effectively decreased the serum uric acid levels of oxonate-induced hyperuricemic rats. Free and bound phenolic extracts from these materials contained significant amounts of phenolics, with free phenolics dominated by chlorogenic acid and p-coumaric acid while bound phenolics dominated by p-coumaric acid and ferulic acid. Free and bound phenolics of adlay bran exhibited significant xanthine oxidase inhibition activities, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities, oxygen radical absorbance capacities, and superoxide radical scavenging activities. Adlay bran phenolics could be effective xanthine oxidase inhibitors and radical scavengers. p-Coumaric acid is a xanthine oxidase inhibitor with strong superoxide radical scavenging activity. However, ferulic acid is a xanthine oxidase inhibitor with weak superoxide radical scavenging activity. Chlorogenic acid is a superoxide radical scavenger with weak xanthine oxidase inhibitory activity.

Water-soluble polysaccharides of Rabdosia serra leaf and stem were fractionated by ultrafiltration and DEAE-Sepharose fast flow chromatogram to obtain water (RSLP-I and RSSP-I), 0.1M NaCl (RSLP-II and RSSP-II) and 0.2M NaCl (RSLP-III and RSSP-III) eluates. Their molecular weights were determined by high performance gel permeation chromatography. Monosaccharide composition analysis indicated that the water eluates comprised of rhamnose, arabinose, xylose, mannose, glucose and galactose. The ascending percentage of galactose and descending percentage of glucose in the eluates were observed with the increase of NaCl concentration. The branched RSLP-I and RSSP-I were composed mainly of →6)-Glcp-(1→, →6)-Galp-(1→, and →5)-Araf-(1→ residues with the ratio of 15.0:4.2:3.8 and 5.5:6.4:3.5, respectively. However, a low level of 1,6-linked glucosyl was observed in RSLP-II, RSSP-II, RSLP-III and RSSP-III. The structural characteristics were further analysed by infrared spectrophotometry. The purified leaf and stem polysaccharides possessed moderate antioxidant capacities., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Summary: Moringa oleifera leaf (MOL) is an excellent source of high‐quality plant protein. MOL hydrolysate (MOLH) was prepared by enzymatic hydrolysis and ethanol precipitation. The adsorption kinetics of SP‐207 resin for antioxidant peptides from MOLH were studied. The adsorption process for antioxidant peptides on SP‐207 was well described by the pseudo‐second‐order kinetics model. The adsorption was a multi‐molecule layer adsorption process, which was exothermic. The peptide fraction with antioxidant activity (MOLP, 40% ethanol elution fraction) possessing high contents of antioxidant and hydrophobic amino acids was obtained by SP‐207 column chromatography. A total of eight dipeptides including PR, L(I)K, L(I)H, L(I)P, L(I)L(I), GE, VL(I) and PF were identified in gastrointestinal digest of MOLP by UPLC‐QTOF‐MS/MS. The protective effects of MOLP digest and LH on oxidatively damaged erythrocytes by inhibition of MDA formation were comparable to that of GSH, indicating that MOLP could be used as an antioxidative ingredient in functional food. MOLP obtained by enzymatic hydrolysis and ethanol precipitation and then purified by SP‐207 column chromatography could be used as an antioxidative ingredient in functional food. [ABSTRACT FROM AUTHOR]

Summary: The high‐acid apple (Malus sieversii f. niedzwetzkyana (Dieck) Langenf) possessing deep red peel and light red flesh is widely distributed in China. To determine if a useful apple variety is being ignored, the monomeric phenolic profiles and antioxidant activities of peel, flesh, pomace, whole fruit and juice were evaluated. The results were compared to those of ‘Fuji’ and ‘Granny Smith’ apples. The high‐acid apple possessing the highest total phenolic and anthocyanin contents among three apple varieties contained the most chlorogenic acid, phloridzin, epicatechin, ferulic acid, catechin, vanillic acid, p‐coumaric acid and caffeic acid. The extraction yields of phenolics (64%) and anthocyanins (89%) from the high‐acid apple to juice were the highest. The high‐acid apple possessing the greatest antioxidant activity had the strongest antihaemolysis activity, indicating that it could be used to produce juice and value‐added ingredient to assist in the prevention of chronic disease. [ABSTRACT FROM AUTHOR]

Summary: The aim of this work was to analyse the honeysuckle extract (HE) for its in vitro antioxidant activity using the ORAC, reducing power, DPPH and ABTS assays. The effects of HE on the quality characteristics and physicochemical properties of porcine patties during refrigerated storage at 4 °C were studied. Chlorogenic acid contributed about 50% to the antioxidant activity of HE. HE possessing strong antioxidant activity was incorporated into porcine patties at 0.02%, 0.1% and 0.5% concentrations and compared with 0.02% and 0.1% chlorogenic acid as references. The addition of 0.1% HE and chlorogenic acid significantly reduced the loss of hardness, springiness, chewiness and cohesiveness of porcine patties in terms of inhibition of lipid oxidation, formation of protein carbonyls, generation of covalent bonds and tryptophan loss during 15 days of chilled storage. HE could be used in porcine patty as a natural antioxidant. [ABSTRACT FROM AUTHOR]

The adsorption and desorption characteristics of seven macroporous resins on the antioxidants in soy sauce were investigated. SP-207 and SP-825 resins possessing good adsorption and desorption capacities were studied further. The pseudo-second-order kinetics and Langmuir isotherm models were demonstrated to be appropriate to describe the whole exothermic and physical adsorption processes of antioxidants onto resins. The 60% ethanol eluted fraction from soy sauce purified by SP-825 resin column possessed the strongest antioxidant activity. The antioxidant activities and contents of typical soy isoflavones, furanones, pyranones, and phenolic acids in soy sauce were determined. These compounds contributed to 50.02% of the total antioxidant activity of the SP-60% fraction. The key small molecule antioxidant compounds in soy sauce were identified as 4-ethylguaiacol, catechol, daidzein, and 4-ethylphenol by the antioxidants omission experiments. Additionally, the purified active fraction with high contents of antioxidants from soy sauce could be applied as bioactive ingredient in food industry. [ABSTRACT FROM AUTHOR]

The antioxidant activities and xanthine oxidase inhibition effects of walnut fruit, stem and leaf were studied in this work. The total phenolic contents were in a descending sequence: shell extract > leaf extract > stem extract > defatted walnut kernel ( DWK) extract > green husk extract ( GHE). The sequence of total phenolic contents was in agreement with the sequence of antioxidant capacities evaluated by ferric reducing antioxidant power and oxygen radical absorbance capacity ( ORAC) assays except for DWK extract. The walnut shell extract showed the highest phenolic content (14.81 gallic acid equivalent g/100 g dry extract) and the best antioxidant activity (the ORAC value was 3423.44 ± 142.52 μmol Trolox equivalents g−1). All tested samples possessed xanthine oxidase inhibitory ( XOI) effects, the inhibition percentages of which were >50% at 2 mg mL−1 except for stem and DWK extracts. The contents of the major compound (hydrojuglone) in all extracts were in a descending order: GHE > walnut stem extract > walnut shell extract > walnut leaf extract > DWK extract. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, the performance and separation characteristics of two macroporous resins for the purification of phenolics from Rabdosia serra were evaluated. Both HP-20 and XAD-7HP resins were effective for phenolics enrichment, with insignificant difference of adsorption/desorption behaviors, according to their chemical and physical properties. The pseudo-second-order kinetics model was the most favorable for illustrating the whole exothermic adsorption process, which was affected by the mutual effects of boundary layer diffusion and intraparticle diffusion kinetics. After treatment with gradient elution on resin columns, phenolics (from 16.66% to 67.87% by HP-20 and to 58.81% by XAD-7HP), antioxidants (3–4 times more than original) and rosmarinic acid (from 10.14% to 67.26% by HP-20 and to 63.16% by XAD-7HP) were enriched in 30% ethanol fractions. The production of highly concentrated phenolics and rosmarinic acid might expand the application of Rabdosia serra as a bioactive agent for both the food industry and pharmacy. [Copyright &y& Elsevier]

Abstract: Rabdosia serra has been used in traditional Chinese medicine for centuries. In order to illustrate the pharmaceutical activity of R. serra as hypoglycaemic and skin-whitening agents, rosmarinic acid (confirmed as the major compound in R. serra), methyl rosmarinate and pedalitin isolated from R. serra were evaluated for their inhibitory effects and mechanisms on tyrosinase and α-glucosidase. The inhibitory effects on both tyrosinase and α-glucosidase were in decreasing order, pedalitin>methyl rosmarinate>rosmarinic acid. The IC50 values for the tyrosinase and α-glucosidase activity inhibited by pedalitin were 0.28 and 0.29mM, respectively. Both rosmarinic acid and methyl rosmarinate were considered as noncompetitive inhibitors of tyrosinase, while pedalitin was suggested to be a mixed-type inhibitor of tyrosinase. In the assay of α-glucosidase inhibition, rosmarinic acid was found to be a competitive inhibitor, whereas both methyl rosmarinate and pedalitin were considered as mixed-type inhibitors. [Copyright &y& Elsevier]

Abstract: Ultrasound-assisted extraction was employed to prepare polysaccharides from Isodon lophanthoides var. gerardianus (Bentham) H. Hara (Xihuangcao). Response surface methodology was used to optimize the ultrasound-assisted extraction parameters. Central-composite design was applied to estimate the effects of ultrasonic time, liquid/solid ratio and pH on the yield of the polysaccharides from I. lophanthoides var. gerardianus (Bentham) H. Hara (ILHP). A mathematical model with high fitness was obtained. Ultrasonic time, liquid/solid ratio and pH exhibited independent and interactive effects on ILHP yield. Gas chromatography analysis suggested that ILHP-3 comprised Rha, Man, Glc with relative molar percentages of 3.9%, 8.0% and 88.1%, respectively. The assay of glycosidic linkage showed that ILHP-3 was consisted of →2)-Man-(1→, →6)-Glc-(1→, →3)-Rha-(1→ with a molar proportion of 1.9:26.5:1. The average molecular weight of ILHP-3 was measured to be 247kDa by high-performance gel permeation chromatography. Furthermore, a good antioxidant activity was observed for ILHP-3. [Copyright &y& Elsevier]

Abstract: The leaf and stem of Rabdosia serra were extracted by different solvents in this work. The results indicated that 60% ethanol was the most suitable solvent for efficiently extracting antioxidants with strong free radical-scavenging capacity and ferrous ion chelating capacity. The butanol and 60% ethanol extracts of stem, methanol and 60% ethanol extracts of leaf were analysed by HPLC–PDA. A similar chemical composition was observed for these stem and leaf extracts. The major compound was obtained by column chromatography and identified by mass spectrometry and nuclear magnetic resonance spectroscopy, which was confirmed to be rosmarinic acid. The contents of rosmarinic acid were in a descending order: butanol extract of stem>60% ethanol extract of leaf>60% ethanol extract of stem>methanol extract of leaf. [ABSTRACT FROM AUTHOR]

In this study, the adsorption and desorption characteristics of six macroporous resins including XAD-7HP, XAD-16, HP-20, HP-2MGL, SP-207 and SP-825 for enrichment of adlay bran free phenolics were studied. XAD-16, SP-207 and SP-825 were chosen for further study due to their strong adsorption and desorption capacities. XAD-16, SP-207 and SP-825 had similar phenolics adsorption/desorption behaviors. Pseudo -second-order kinetics model and Freundlich isotherm model were suitable for describing the whole exothermic and physical adsorption processes of adlay bran free phenolics on XAD-16, SP-207 and SP-825. After treatment with gradient elution on XAD-16 resin column, the free phenolics were mostly enriched (from 89.61 to 1015.26 mg/100 g) in 50% ethanol fraction. The oxygen radical absorbance capacity of 50% ethanol fraction was eight times higher than that of the crude extract. Therefore, the production of highly concentrated phenolics might expand the application of adlay bran used as a bioactive ingredient in functional food. [ABSTRACT FROM AUTHOR]

Defatted walnut meal (DWM), a main byproduct of walnut oil production, is rich in proteins with a high essential amino acid content. Our research was focused on the functional activities of defatted walnut meal hydrolysate (DWMH). DWMH exhibited relatively strong hydroxyl scavenging and oxygen radical absorbance capacities, protective effect on H 2 O 2 -injured PC12 cells compared with GSH and cerebrolysin. Besides, DWMH could combat d -galactose induced learning and memory impairments in the Morris water maze test and in the Dark/light avoidance test of mice. Seventy-seven peptides were identified by UPLC-ESI-MS/MS in the most potent antioxidative fraction of DWMH. WSREEQEREE and ADIYTEEAGR were the peptides that most likely accounted for the suppression of H 2 O 2 -induced apoptosis in PC12 cells. The mixture of the commercially available amino acids did not offer any protection on H 2 O 2 -injured PC12 cells, suggesting that amino acid sequence rather than amino acid composition was the dominant influencing factor. DWMH could be recommended as natural antioxidants for the development of functional foods targeting memory impairments. [ABSTRACT FROM AUTHOR]