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Summary: There is an urgent need for safe and effective bile acid sequestrants from edible plants to treat hyperlipidaemia. Moringa oleifera leaf has been reported to be a source of hypolipidaemic agents. However, limited information is available on the bile acid‐binding capacity of M. oleifera leaf polysaccharide fraction (MOLPF). To illustrate structure‐bile acid‐binding capacity relationship of MOLPFs obtained by eight common extraction methods and provide an extraction technique for MOLPF with strong bile acid‐binding capacity, structure characteristics and bile acid‐binding capacities of MOLPFs were investigated. The results indicated that extraction method greatly affected morphology, monosaccharide composition, glycosidic linkage and molecular weight distribution of MOLPF. MOLPFs with lower contents of galactose and more branched components exhibited lower binding rates. MOLPFs prepared by cellulase and ultrasonic‐assisted cellulase extraction methods possessing the highest contents of galactose and relatively high proportions of linear macromolecules exhibited the strongest binding capacities, showing potential hypolipidaemic effects. [ABSTRACT FROM AUTHOR]

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]

Summary: Maca is known to be rich in macamides. The objective of this study was to analyse macamide profiles of macas with different colours cultivated in Yunnan, China, and commercial Peru maca by ultra‐high‐performance liquid chromatography–tandem mass spectrometry. The antioxidant activities of water, citric acid and alkali‐extracted polysaccharides from Yunnan and Peru macas were evaluated via DPPH radical scavenging activity, oxygen radical absorbance capacity and erythrocyte haemolysis inhibition effect assays. Six major macamides present in Peru maca were also found dominant in Yunnan maca at comparable concentrations. Maca polysaccharide effectively scavenging DPPH and peroxyl radicals protected the erythrocytes against H2O2‐induced haemolysis by inhibition of malondialdehyde (MDA) generation. Citric acid extraction was found the most suitable preparation method for generating heteropolysaccharide with strong antioxidant activity. Black maca cultivated in Yunnan possessing the most abundant macamides and polysaccharide with strong antioxidant activity could be developed as functional foods. [ABSTRACT FROM AUTHOR]

Hyperuricemia is a common metabolic disorder disease in human and is associated with increased xanthine oxidase (XOD) activity. This study was aimed to evaluate the antihyperuricemic activities of an ethanolic and aqueous extract of walnut ( Juglans regia L.) shell in vivo and obtain active compounds with high xanthine oxidase inhibitory (XOI) activities and distinct chemical structures form allopurinol in vitro. Finally, the structure-XOI activity relationship of the active compound was further discussed based on the molecular docking. The in vivo antihyperuricemic study indicated that the walnut shell extract (WSE) could decrease the serum uric acid levels significantly (20-days treatment, P < 0.05; 30-days treatment, P < 0.01). And a new aldehyde XOD inhibitor with high XOI activity was obtained through XOI activity-guided purification in vitro. The studies of structure-XOI activity relationship and molecular docking indicated that the synergy of aldehyde group, double bond and hydroxyl group at C-4 in p-coumaric aldehyde was the critical contributor for its high XOI activity. [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]