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BACKGROUND: Besides in vitro fecal fermentation model, a few supplementary methods have been constructed for high‐throughput screening of polysaccharides with hypoglycemic potentials. The purpose of this study was to establish a co‐culture fermentation model constructed by gut microbiota relating to glucose and lipid metabolism as a supplementary method for comparatively evaluating the proliferative effects and hypoglycemic potentials of typical plant polysaccharides, e.g. konjac glucomannan, Lycium barbarum L. polysaccharide, oat glucan and alga‐derived fucoidan. RESULTS: The results showed that the mixing culture medium of butyrate‐producing bacteria, Bacteroides, Bifidobacterium and Lactobacillus at a ratio of 50:40:9:1 was optimal. This testing model in line with quantitative polymerase chain reaction (qPCR) and metabolite analysis multi‐dimensionally differentiated four polysaccharides possessing different behaviors on proliferation of total bacteria and specific genus or strain and accumulation of short chain fatty acids. CONCLUSION: Our study provided crucial data for establishing an initial screening method for proliferative effect/specific structure‐oriented extraction of polysaccharide with hypoglycemic potential. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of bergamot polysaccharide (BP) and Laoxianghuang polysaccharides (LPs, fermented bergamot) on the microbiome and metabolome during the in vitro fermentation of gut microbiota from patients with hyperlipidemia. Results indicated that both BP and LPs were able to increase the production of acetic acid, propionic acid, and butyric acid. However, only LPs could decrease the content of isobutyric acid and isovaleric acid, which are detrimental to gut health. A 16S rRNA analysis showed that both BP and LPs could reduce the proportion of Fusobacterium, whereas they increased the Bacteroides content in hyperlipidemia. Untargeted UPLC-MS/MS metabolomic profiling found six bio-markers that were significantly changed after BP and LPs intervention, and four of the down-regulated metabolites were long-chain fatty acids associated with vascular diseases. These findings provide new evidence that BP and LPs have the potential to regulate imbalances in the gut microbiota in patients with hyperlipidemia and ameliorate its metabolic abnormalities. [ABSTRACT FROM AUTHOR]

The current study aimed to assess the anti-diabetic effects and potential mechanisms of two Sargassum fusiform polysaccharide fractions (SFPs, named SFP-1 and SFP-2). The carbohydrate-loading experiment revealed that SFP-2 could control postprandial hyperglycemia by inhibiting the activity of digestive enzymes in rats. The analysis of diabetic symptoms and serum profiles indicated that SFPs could mitigate diabetes accompanied by dyslipidemia, and SFP-2 showed better regulatory effects on body weight, food intake and the levels of total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C) and free fatty acid (FFA) in diabetic rats. Intestinal bacterial analysis showed that SFP treatment could reshape the gut flora of diabetic rats, and SFP-2 possessed a greater regulatory effect on the growth of Lactobacillus and Blautia than SFP-1. RT-qPCR analysis revealed that SFPs could regulate the genes involved in the absorption and utilization of blood glucose, hepatic glucose production and lipid metabolism, and the effects of SFP-2 on the relative expressions of Protein kinase B (Akt), Glucose-6-phosphatase (G-6-Pase), Glucose transporter 2 (GLUT2), AMP-activated protein kinase-α (AMPKα), Peroxisome proliferator-activated receptor γ (PPARγ) and Cholesterol 7-alpha hydroxylase (CYP7A1) were greater than SFP-1. All above results indicated that SFPs could be exploited as functional foods or pharmaceutical supplements for the treatment of diabetes and its complications. [ABSTRACT FROM AUTHOR]

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]

Rabdosia serra is well known for its antibacterial, anti-inflammatory and antitumor activities, but no information has been available for the active compounds derived from this plant in inhibiting human nasopharyngeal carcinoma (NPC) cell growth. In this study, we isolated and purified a natural diterpenoid from Rabdosia serra and identified its chemical structure as effusanin E and elucidated its underlying mechanism of action in inhibiting NPC cell growth. Effusanin E significantly inhibited cell proliferation and induced apoptosis in NPC cells. Effusanin E also induced the cleavage of PARP, caspase-3 and -9 proteins and inhibited the nuclear translocation of p65 NF-κB proteins. Moreover, effusanin E abrogated the binding of NF-κB to the COX-2 promoter, thereby inhibiting the expression and promoter activity of COX-2. Pretreatment with a COX-2 or NF-κB-selective inhibitor (celecoxib or ammonium pyrrolidinedithiocarbamate) had an additive effect on the effusanin E-mediated inhibition of proliferation, while pretreatment with an activator of NF-κB/COX-2 (lipopolysaccharides) abrogated the effusanin E-mediated inhibition of proliferation. Effusanin E also significantly suppressed tumor growth in a xenograft mouse model without obvious toxicity, furthermore, the expression of p50 NF-κB and COX-2 were down-regulated in the tumors of nude mice. These data suggest that effusanin E suppresses p50/p65 proteins to down-regulate COX-2 expression, thereby inhibiting NPC cell growth. Our findings provide new insights into exploring effusanin E as a potential therapeutic compound for the treatment of human nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

Rabdosia serra has been widely used for the treatment of the various human diseases. However, the antiproliferative effects and underlying mechanisms of the compounds in this herb remain largely unknown. In this study, an antiproliferative compound against human nasopharyngeal carcinoma (NPC) cells from Rabdosia serra was purified and identified as lasiodin (a diterpenoid). The treatment with lasiodin inhibited cell viability and migration. Lasiodin also mediated the cell morphology change and induced apoptosis in NPC cells. The treatment with lasiodin induced the Apaf-1 expression, triggered the cytochrome-C release, and stimulated the PARP, caspase-3 and caspase-9 cleavages, thereby activating the apoptotic pathways. The treatment with lasiodin also significantly inhibited the phosphorylations of the AKT, ERK1/2, p38 and JNK proteins. The pretreatment with the AKT or MAPK-selective inhibitors considerably blocked the lasiodin-mediated inhibition of cell proliferation. Moreover, the treatment with lasiodin inhibited the COX-2 expression, abrogated NF-κB binding to the COX-2 promoter, and promoted the NF-κB translocation from cell nuclei to cytosol. The pretreatment with a COX-2-selective inhibitor abrogated the lasiodin-induced inhibition of cell proliferation. These results indicated that lasiodin simultaneously activated the Apaf-1/caspase-dependent apoptotic pathways and suppressed the AKT/MAPK and COX-2/NF-κB signaling pathways. This study also suggested that lasiodin could be a promising natural compound for the prevention and treatment of NPC. [ABSTRACT FROM AUTHOR]