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This study focused on the enzymatic characteristics, with regard to primary specificity, secondary specificity, and hydrolysis ability of five proteases (Alcalase, Protamex, papain, Flavourzyme, and ProtexA), towards the release of dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides from bovine casein. The secondary specificity of the five proteases, especially the release capability for Xaa-Pro-type peptide played a determining role in the release of DPP-IV inhibitory peptides from bovine casein. Moreover, protease combinations, chosen based on their Xaa-Pro-type peptide release abilities, resulted in superior DPP-IV inhibitory activity compared to other combinations. Particularly, the hydrolysate with the highest DPP-IV inhibitory activity (IC 50 value of 0.45 ± 0.07 mg/mL) was obtained by the combination hydrolysis of ProtexA and papain, achieving a 74.63% ± 1.62% (peak area) release of Xaa-Pro-type peptide, and a significant improving glucose tolerance in mice (33.42% ± 1.68% reduction of blood glucose AUC compared with control mice). The mechanistic insights revealed that papain efficiently released long Xaa-Pro-type peptides in the early hydrolysis stage, and subsequently, the synergistic effect of papain and ProtexA led to an accelerated and extensive release of short Xaa-Pro-type peptides. These findings provide valuable insight into enzymatic processes for generating DPP-IV inhibiting peptides from casein. [Display omitted] • The enzymatic characteristics of Alcalase, Protamex, papain, Flavourzyme, and ProtexA on the release of DPP-IV inhibitory peptides from casein were studied. • Secondary specificity of proteases determined the release of DPP-IV inhibitory peptides. • Protease combinations, based on their Xaa-Pro-type peptide release abilities, could release more DPP-IV inhibitory peptides. • Casein hydrolyzed by the combination of ProtexA and papain had a 74.63% ± 1.62% release of Xaa-Pro-type peptide. [ABSTRACT FROM AUTHOR]

Probiotic fermentation is attractive for beverage processing. However, its regulatory role in quality of coix seed-chrysanthemum beverage (CCB) rich in phenolics and polysaccharides was unknown. Results showed that co-fermentation with Bifidobacterium animalis subsp. lactis BLa80 (BLa80), Lactobacillus delbrueckii subsp. bulgaria LB42 (LB42), Streptococcus salivarius subsp. thermophilus ST81 (ST81), and Lactobacillus plantarum LP90 (LP90) for 12 h combined their respective advantages to prepare fermented CCB with viable counts of 8.78 lg CFU/mL, high phenolics bioaccessibility (>60 %), good sensory quality, and strong antioxidant activity. LP90 greatly contributed to the aroma. BLa80 and LP90 hydrolyzed resistant starch/polymer dextrin. BLa80 showed the strongest deglycosidic ability, decreasing bitterness. The compound probiotic fermentation led to the biotransformation of endogenous polysaccharides/phenolics and introduction of exogenous viable probiotics resistant to gastrointestinal digestion, facilitating the proliferation of beneficial gut microbiota and accumulation of their metabolites. These findings provided a useful strategy for dual regulation of high quality of plant-based beverage. [Display omitted] • Probiotics were effective in fermenting coix seed-chrysanthemum beverage (CCB). • Different probiotics contributed differently to biotransform functional constituents. • Co-fermentation effectively reduced the bitterness and astringency of CCB. • Co-fermentation led to complex and balanced aroma of CCB. • Fermented CCB showed good intestinal health-promoting effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-quality Chenpi EO was obtained by supercritical fluid extraction at 25 MPa. • Chenpi flavouring essence was optimally prepared by microencapsulation of EO. • Microencapsulation improved thermostability and water dispersibility of Chenpi EO. • Chenpi flavouring essence reduced 20% usage of sucrose and salt via specific aroma. • Chenpi flavouring essence had dual effects on sweetness and saltiness enhancement. To obtain flavouring essence with application potential in sugar and salt-reduced foods, the optimal strategy for extraction and microencapsulation of essential oil (EO) from Chenpi was investigated. UPLC-QTOF-MS/MS and liquid–liquid-extraction-GC–MS confirmed the selectivity for volatiles ranked in hydrodistillation > supercritical fluid extraction > solvent extraction. The aroma characteristic of Chenpi EO was distinguished by 33 key volatiles (screened out via headspace-SPME-GC–MS) and quantitative descriptive analysis. EO extracted by supercritical fluid extraction was preferred for preserving the original aroma of Chenpi and displaying more fruity, honey and floral. Chenpi flavouring essence with superior encapsulation efficiency, particle size, water dispersibility, and thermostability was obtained through optimally microencapsulating EO with gum arabic and maltodextrin (1:1) by high-pressure homogenization coupled with spray drying. Chenpi flavouring essence was able to reduce the usage of sugar and salt by 20 % via enhancing flavour perception of sweetness and saltiness. This study first developed a flavouring essence promisingly effective in both sugar and salt-reduced foods. [ABSTRACT FROM AUTHOR]

Galangal extract (GE)-based hypouricemic functional food is under-developed due to ambiguous quality control standard that is closely associated with action mechanisms and interaction of key xanthine oxidase (XO) inhibitors (kaempferide and galangin) in GE. In terms of kinetics analysis, fluorescence quenching and molecular docking, kaempferide and galangin showed similar docking posture to xanthine in molybdopterin center, and formed flavonol-XO complexes driven by hydrogen bonding, hydrophobic interaction and van der Waals force, competitively inhibiting XO. Kaempferide, had stronger binding affinity for XO and three more hydrogen bonds with XO than galangin, interacting with critical amino acid residues (Arg880 and Glu802) in catalysis reaction of XO and showing stronger XO inhibitory activity than galangin. The combination of kaempferide and galangin enhanced their binding affinities for XO, showing synergistic inhibition on XO at optimal molar ratio 1:4 that could be quality control standard for GE. This study provided new insights into structure-XO inhibitory activity relationship of methoxylated flavonoids and quality control standard for GE-based hypouricemic functional food. Unlabelled Image • Kaempferide and galangin inhibited xanthine oxidase in competitive manners. • Methoxy substitution enhanced xanthine oxidase inhibitory activity of galangin. • Kaempferide had stronger binding affinity for xanthine oxidase than galangin. • Kaempferide interacted with Arg880 and Glu802 in molybdopterin center. • Kaempferide had strong synergistic effect with galangin at molar ratio of 1:4. [ABSTRACT FROM AUTHOR]

Sulfated fucan chondroitin sulfate-dominated polysaccharide fraction from low-edible-value sea cucumber may be a good alternative to high-edible-value sea cucumber-derived polysaccharide for application in hypoglycemic functional foods. To evaluate the potential effect of low-edible-value sea cucumber-derived polysaccharide fraction on type 2 diabetes (T2DM), two sulfated fucan/fucosylated chondroitin sulfate-dominated polysaccharide fractions screening from 10 global commercial low-edible-value sea cucumber species were investigated to identify their anti-diabetics efficacies using a high-fat diet and streptozotocin-induced T2DM rat model. Sulfated fucan-dominated polysaccharide fraction from Thelenota ananas and fucosylated chondroitin sulfate-dominated polysaccharide fraction from Cucumaria frondosa ameliorated hyperglycemia, restored hypertriglyceridemia and hypercholesterolemia, decreased inflammatory status and oxidative stress, protected against liver injury, as well as improved insulin resistance and promoted accumulation of hepatic glycogen by activating IRS/PI3K/AKT signaling and regulating GSK-3β gene expression in T2DM rats. The current findings provide an available strategy for the commercialization of sea cucumber polysaccharide based-hypoglycemic functional food. Unlabelled Image • Two low-edible-value sea cucumber polysaccharide fractions were obtained. • Two polysaccharide fractions ameliorated hyperglycemia and dyslipidemia. • Two polysaccharide fractions decreased inflammation and oxidative stress. • Two polysaccharide fractions protected liver and promoted glycogen synthesis. • Two polysaccharide fractions regulated IRS/PI3K/AKT signaling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Submicroparticles promoted the absorption of chrysanthemum phenolics. • Submicroparticles accounted to 22% of chrysanthemum tea infusion's soluble solids. • Esterified pectin provided spherical skeleton to form submicroparticles. • Phenolics attached to the external region of spherical pectin by hydrogen bonds. • Phenolics attached to the internal cavities of pectin by hydrophobic interactions. Submicroparticles are important components generally existed in chrysanthemum tea infusion, but their functionality, chemical composition, structure and self-assembly mechanism are unclear due to lack of suitable preparation method and research strategy. This study showed that submicroparticles promoted the intestinal absorption of phenolics in chrysanthemum tea infusion by comparison of chrysanthemum tea infusion, submicroparticles-free chrysanthemum tea infusion and submicroparticles. Submicroparticles efficiently prepared by ultrafiltration mainly consisting of polysaccharide and phenolics accounted for 22% of total soluble solids in chrysanthemum tea infusion. The polysaccharide, which was determined as esterified pectin with a spherical conformation, provided spherical skeleton to form submicroparticles. A total of 23 individual phenolic compounds were identified in submicroparticles with the total phenolic content of 7.63 μg/mL. The phenolics not only attached to the external region of spherical pectin by hydrogen bonds, but also got into hydrophobic cavities of spherical pectin and attached to the internal region by hydrophobic interactions. [ABSTRACT FROM AUTHOR]

Lycium barbarum fruit (wolfberry) is rich in rhamnogalacturonan-I (RG-I) pectin with favorable prebiotic activity. However, there is currently limited research on the targeted extraction of RG-I type pectin from Lycium barbarum fruit (LBP). DES is widely recognized as an efficient solvent for extracting bioactive compounds from plants. In this study, a mixture of choline chloride (ChCl) and propylene glycol (PG) at the molar ratio 1:2 with 20 wt% water content was optimal to extract LBP. The yield and extent of branching of LBP extracted by ChCl-PG-water system (LBP-P) were 1.74-fold and 2.87-fold higher than those of LBP extracted by water (LBP-W), respectively. Compared with LBP-W, LBP-P exhibited higher total neutral sugar and uronic acid contents, as well as lower molecular weight and viscosity. The proliferative ability of LBP-P on six Bifidobacterial strains was 1.06–1.92-fold greater than that of LBP-W. In addition, Fourier transform infrared spectroscopy (FTIR) and apparent viscosity proved that the role of water was to maintain strong hydrogen bonds of DES with reduced viscosity. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra and density functional theory (DFT) calculations proved that the role of DES was to penetrate cell walls and interact with target substances. The effective extraction mechanism of the DES-water system was based on cell wall cellulose disassembly, side chain exposure, and high-branched LBP dissolution stages. Our results provided a theoretical basis for targeted extraction of RG-I pectin using new solvents. [Display omitted] • DES-water system was used to extract RG-I wolfberry pectin polysaccharide (LBP). • The DES-water system extraction method was high-efficient for LBP extraction. • LBP prepared by DES-water system showed a strong prebiotic activity. • The underlying mechanism of DES-water system for efficient extraction was clarified. [ABSTRACT FROM AUTHOR]

Currently, there is a shortage of lotus leaf pectin-type polysaccharide (LLP)-based prebiotic functional foods due to its low extraction efficiency and indistinct prebiotic and functional properties. In the study, medium-temperature alkali water, deep eutectic solvent, high pressure homogenization-assisted dual enzyme, and reflux extraction methods were used to screen out a process for LLP with high extraction efficiency, in vitro prebiotic activity, and functionality. It was demonstrated that LLPs prepared by high pressure homogenization-assisted dual enzyme, deep eutectic solvent (choline chloride and urea) and reflux extraction methods showed excellent prebiotic activities. Among them, LLP prepared by high pressure homogenization-assisted dual enzyme extraction (LLP-EP) had high extraction efficiency, high purity, high content of RG-I domain, fine homogeneity, low esterification degree, strong in vitro prebiotic activity, and comprehensive functional properties i.e. good water dispersibility and stability, rheological property, and emulsification stability. According to the structure-activity relationship analysis using a series of partially acid-hydrolyzed LLP-EP as prebiotics, the prebiotic activity of LLP-EP was mainly depended on high content of RG-I domain. These findings indicated that LLP had the potential to be used in beverages-based prebiotic functional foods, and also provided the theoretical basis for structural features of pectins to be better prebiotics. [Display omitted] • Five lotus leaf polysaccharides prepared by different processes were pectins. • Three lotus leaf polysaccharides effectively proliferated human gut probiotics. • Polysaccharide via homogenization-assisted enzymolysis showed strong prebiotic effect and comprehensive functionality. • Structure-prebiotic activity relationship of optimal polysaccharide was elaborated. [ABSTRACT FROM AUTHOR]

In this study, phenolic profiles of chrysanthemums derived from five main species were determined for characterization of rationality of their application in tea, beverages and functional foods. A total of 41 phenolics including 3 phenolic acids, 17 flavones, 9 flavanones, 1 dihydroflavonol, 4 flavonols, 4 chalcones and 3 aurones were identified. The contents of 22 characteristic phenolics were simultaneously determined. Chrysanthemum morifolium cv. ' Qiju ' (with abundant phenolics) and Coreopsis tinctoria Nutt. (with unique and abundant flavonoid aglycones and glycosides), exhibited excellent cellular antioxidant activities and strong market potentials. Chlorogenic acid, 3,5-dicaffeoylquinic acid and luteolin-7- O -glucoside largely contributing to cellular antioxidant activity of ' Qiju ' by forming protective membrane around erythrocyte should be markers for quality control of ' Qiju '. Okanin, the gut microbial-produced metabolite of marein, possessed strong protective effect on oxidatively damaged erythrocyte via incorporating in membrane and entering cytoplasm. Okanin and marein should be markers for quality control of C. tinctoria. Unlabelled Image • Chrysanthemums derived from five main species were classified by phenolic profiles. • C. morifolium cv. ' Qiju ' and C. tinctoria had good cellular antioxidant activities. • Phenolic acids were identified as marker compounds of C. morifolium cv. ' Qiju '. • Okanin and marein were identified as marker compounds of C. tinctoria. • Marker phenolics enhanced nonenzymatic and enzymatic antioxidant defense systems. [ABSTRACT FROM AUTHOR]

Highlights • Catechin inhibited protein oxidation in linoleic acid-lipoxygenase reaction system. • Catechin promoted gastrointestinal digestibility of oxidized β -conglycinin. • Catechin improved antioxidant activity of oxidized β -conglycinin digest. • Catechin increased abundance of di-/tripeptide in oxidized β -conglycinin digest. Abstract The aim of the present study was to enhance oxidative stability and bioaccessibility of β -conglycinin (7S) prepared from low denatured defatted soybean flours with residual lipids and high lipoxygenase (LOX) activity. The model system consisting of linoleic acid (LA), LOX and unheated 7S (UH-7S)/heated 7S (H-7S) or UH-7S-catechin/H-7S-catechin complex, and in vitro gastrointestinal (GI) digestion model were used to investigate the effect of complexation with catechin on protein oxidation and characterisation of GI digest. The interaction of UH-7S/H-7S with catechin dramatically inhibited LOX-catalyzed LA peroxidation-induced protein oxidation. The interaction also promoted the degree of proteolysis in GI digestion and intestinal absorption for oxidized UH-7S/H-7S, increasing the antioxidant activity of oxidized UH-7S/H-7S, bioaccessibility for catechin and release of di-/tripeptides with dipeptidyl peptidase-IV/angiotensin converting enzyme inhibitory effects or antioxidant activities during GI digestion. The complexation with catechin is a potential strategy to enhance the oxidative stability, GI digestibility and bioaccessibility of 7S. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • TPC, TFC, XOI, ORAC and OSA of 50 plant extracts were characterized. • Galangal extract was a dual-acting agent with XOI and antioxidant activity. • Galangal extract had significant hypouricemic effect and renal protective effect. • Galangin, kaempferide and 3-methoxyl-galangin were key XOD inhibitors in galangal. Abstract This study was aimed at screening a potential anti-hyperuricemia agent with dual xanthine oxidase (XOD) inhibitory effect (XOI) and antioxidant activity from edible plants with health-promoting effects using non-targeted chemometric analysis (hierarchical cluster analysis and principal component analysis), evaluating its in vivo hypouricemic effect and mechanism, and identifying the key XOD inhibitor using ultrafiltration UPLC-MS/MS. Rhizoma Alpiniae Officinarum extract (GE), which has high contents of total phenolics and flavonoids, as well as dual XOI and antioxidant activity, showed significant hypouricemic and renal protective effects on hyperuricemic rats through inhibiting XOD activity, alleviating oxidative stress, down-regulating URAT1 and GLUT9 protein expression, and reducing urea nitrogen and creatinine levels. GE could be a dual-acting agent with XOI and uricosuric effect for preventing and treating hyperuricemia. Four flavonoids and eight diarylheptanoids were identified as potential XOD inhibitors from GE. Galangin, kaempferide and 3-methoxyl-galangin contributing to 70.1% of XOI were the key XOD inhibitors. [ABSTRACT FROM AUTHOR]

Natural functional hydrophilic colloids with glycolipid-lowering activities have remarkable application prospects but scarce. Moringa oleifera Lam. leaf (MOL) is a good candidate for novel plant-based functional hydrophilic colloid, but the development of high-purity MOL polysaccharide (MOLP) is limited due to high protein and pigment contents in MOL and bottleneck of green preparation. In this study, a green preparation strategy for high-purity MOLP as a functional hydrophilic colloid was established through comparative evaluation of different enzyme-assisted extraction and conventional/non-conventional purification methods on purity and function of MOLP. Liquid nitrogen pulverization coupled with cellulase enzymolysis, high-temperature treatment and yeast fermentation was optimal to extract MOLP. Dual protease enzymolysis in combination of dual resins absorption was screened out as the most efficient purification method for MOLP in comparison with TCA, sevage, enzymolysis, and chromatography methods. High-purity MOLP with high molecular weight exceeding 1000 kDa and high proportions of Ara and Gal showed strong glycolipid absorption inhibitory activity, prebiotic effect on human gut probiotics related to glycolipid metabolism, and good function property e.g. light color, viscoelasticity, emulsibility and water/oil holding capacity, which exceeded commercial pectin in bioactivity and resembled commercial pectin in functionality. The positive correlation between purity of MOLP and function was clarified in terms of correlation coefficients of total sugar content/molecular weight distribution and bioactivity/functionality. It offered theoretical direction for the development of high-purity polysaccharide as functional hydrophilic colloid from leaf-derived raw materials. [Display omitted] • Three-step enzyme-assisted extraction effectively extracted Moringa oleifera Lam. leaf polysaccharide (MOLP). • Dual protease enzymolysis in combination of dual resins was optimal to purify MOLP. • MOLP had stronger glycolipid-lowering activity than commercial pectin. • MOLP had good functional property and resembled commercial pectin. [ABSTRACT FROM AUTHOR]

The search for treatment of aging and age-related diseases is a public health issue. Sea cucumber ( Cucumaria frondosa ) hydrolysate (CFH) prepared by enzymatic hydrolysis and purified by ultrafiltration was examined for its peptide profile and ability to prevent and/or delay aging in fruit flies and age-related neurodegenerative disorders in d -galactose-induced aging mice. CFH contained peptides with low molecular weights (mainly < 3 kDa), Ala, Val and Leu at the N-terminal end and aromatic/hydrophobic/acidic amino acids in sequence. We provided the first in vivo evidence that CFH significantly prolonged the lifespan of fruit flies and ameliorated learning and memory deficits of d -galactose-induced aging mice. The mechanism underlying its protective effect might be associated with the ability to up-regulate Klotho expression, increase the activities of SOD and GSH-Px, inhibit lipid peroxidation and protein oxidation, and down-regulate acetylcholinesterase activity. CFH could be a health-promoting ingredient in coping with aging and age-related diseases. [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]

Defatted soy meal is a candidate for preparing lipid-lowering active ingredient. The study aimed to optimally co-extract soy protein and polysaccharide with lipid-lowering activity and improved functional and nutritional properties using non-conventional extraction techniques, i.e. thermal-, high pressure homogenization- and enzyme-assisted extraction. Non-conventional extraction enhanced the yields of soy protein and soluble saccharides and inactivated anti-nutrients. Soy extract (SE) prepared by pectinase-assisted extraction possessed not only strong in vitro lipid-lowering activity (i.e. cholesterol micellar inhibition activity, bile salts binding capacity, pancreatic lipase inhibition activity and cholesterol esterase inhibition activity), but also excellent functional (i.e. instant solubility of protein, low turbidity and acceptable color) and nutritional properties (i.e. none agglutinin activity). Resistant-digested fragment of 7S/11S played key role in lipid-lowering activity of SE. Moreover, SE beneficially altered colonic fermentation property of soy protein through promoting the release of bioactive peptides and organic acids, accelerating tryptophan and linoleic acid metabolism to produce indole acrylic acid, indole lactic acid and linoleic acid, and inhibiting putrefactive compounds (i.e. piperidine and tyramine). Oligosaccharide and polysaccharide in SE improved functional and nutritional properties of soy protein without compromising its lipid-lowering activity. [Display omitted] • Non-conventional extraction enhanced the yields of soy protein and saccharides and inactivated anti-nutrients. • Soy extract prepared by pectinase assisted extraction possessed strong lipid-lowering activity. • Resistant-digested fragment of 7S/11S played key role in lipid-lowering activity of soy extract. • Saccharides improved functional and nutritional properties of soy protein without compromising its lipid-lowering activity. [ABSTRACT FROM AUTHOR]

Yin-deficiency-heat (YDH) syndrome characterized by inflammatory lesions is a common sub-health state in human body. Chrysanthemum and coix seed are commonly used to improve YDH syndrome. The chemical, volatile, and phenolic profiles and sensory and functional properties of five plant-based solid beverages (PSB) prepared by hydrothermal treatment coupling with enzymatic hydrolysis by amylase and protease using chrysanthemum and coix seed as materials were determined. Chrysanthemum-coix seed beverage had wonderful water solubility, reduced bitter and sour taste, sweet taste, and harmonious aroma. Chrysanthemum phenolics extracted by enzymatic hydrolysis might impact multiple metabolic pathways and biological processes to intervene in inflammation and most of them had high bioaccessibility. PSB promoted the production of beneficial gut microbiota metabolites. Chrysanthemum-coix seed beverages exerted more positive effects on YDH syndrome due to anti-inflammatory phenolics from chrysanthemum and resistant starch/dextrin from coix seed facilitating short-chain fatty acids production. This study provided new sight for developing plant-based beverages with anti-YDH syndrome potential. [Display omitted] • Chrysanthemum-coix seed solid beverage was prepared by enzymatic hydrolysis. • Chrysanthemum-coix seed solid beverage showed improved sensory property. • Most of phenolics in chrysanthemum-coix seed beverage had high bioaccessibility. • Characteristic phenolics in beverage had multi-target anti-inflammatory effects. • Chrysanthemum-coix seed beverage regulated gut microbiota metabolites. [ABSTRACT FROM AUTHOR]

The intracellular antioxidant activities of millet, rice, wheat, brown rice, oat, buckwheat, corn and adlay phenolic extracts were evaluated in an ex vivo erythrocytes system. Buckwheat, corn, and brown adlay free phenolic extracts could effectively attenuate H 2 O 2 -induced erythrocyte hemolysis. The protective effects and involved mechanisms of polished adlay, brown adlay and adlay bran phenolic extracts were studied further. The intracellular antioxidant activities of adlay phenolic extracts decreased in the following order: adlay bran > brown adlay > polished adlay. Adlay bran free phenolic extract possessed stronger intracellular antioxidant activity than chlorogenic acid, p -coumaric acid and ferulic acid. The free phenolic extracts were more effective than bound phenolic extracts to suppress hemolysis and plasma oxidation through inhibition of MDA equivalents, MetHb and ROS generation and to restore the activities of Na + K + -ATPase, Ca 2+ Mg 2+ -ATPase and intracellular antioxidant enzyme to normal levels. Adlay-rich diets could reduce the incidence of cancer, cardiovascular and neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Five tasty peptides were separated from soy sauce, by sensory-guided fractionation, using macroporous resin, medium-pressure liquid chromatography and reverse phase-high performance liquid chromatography, and identified by ultra-performance liquid chromatography tandem mass-spectrometry as ALPEEV, LPEEV, AQALQAQA, EQQQQ and EAGIQ (which originated from glycinin A1bB2-445, glycinin A1bB2-445, cobyric acid synthase, leucine-tRNA ligase and glycoprotein glucosyltransferase, respectively). LPEEV, AQALQAQA and EQQQQ tasted umami with threshold values of 0.43, 1.25 and 0.76 mmol/l, respectively. ALPEEV and EAGIQ had minimal umami taste, but ALPEEV, EAGIQ and LPEEV showed umami-enhancement with a threshold estimated at 1.52, 1.94 and 3.41 mmol/l, respectively. In addition, the synthetic peptides showed much better sensory taste than mixtures of their constitutive amino acids. It indicated that peptides might play an important role in the umami taste of soy sauce. [ABSTRACT FROM AUTHOR]

Xanthine oxidase (XOD) inhibitory activities of five dietary flavonoids pinobanksin, galangin, pinocembrin, pinocembrin-7- O - β - d -glucopyranoside and glabranin were evaluated. Enzyme kinetic studies and molecular docking simulation were conducted to investigate the mechanisms underlying the inhibitory activities. The results showed that these flavonoids exhibited excellent inhibitory activities (which were ranked in the order of pinobanksin > galangin > pinocembrin > pinocembrin-7- O - β - d -glucopyranoside > glabranin) . Competitive inhibition and a mixed-type of competitive–noncompetitive inhibition were observed. The mode of inhibition was dependent on the type and concentration of the substrate and inhibitor. Fluorescence quenching data suggested that these flavonoids could interact with XOD at more than one binding site. The docking simulation revealed that galangin and pinobanksin could enter into the active site of XOD and form hydrogen bonding with amino acid residues (such as Ser-876, Asn-768, Glu-1261 and Thr-1010) and sandwiching aromatic interactions (π–π interactions) around the active site of XOD. [ABSTRACT FROM AUTHOR]

DPPH assay is widely used to evaluate the radical scavenging activities of peptides. Effects of pH and buffers on the stability of DPPH• and its reduced product (DPPHH) in the ethanol-buffer solution were investigated in this study and the reactivity of DPPH• towards several dipeptides was compared to that of 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS• + ) and the peroxyl radicals in oxygen radical absorbance capacity (ORAC) assay. Results showed that the deprotonation of DPPHH under basic condition could interfere with the spectrophotometric measurement at 515–525 nm. It was suggested that the reaction mixture be maintained at a final pH range of 5.0–6.5 in 1:1 ethanol–acetate/citrate buffer medium when evaluating the activities of peptides. Additionally, among tested dipeptides, only Cys-containing dipeptides displayed DPPH• scavenging activity with 0.14–0.28 μmol TE (Trolox equivalent)/μmol, while Tyr/Trp-containing dipeptides with high reactivity towards ABTS• + and peroxyl radicals were inert to DPPH• with TE values less than 0.02. [ABSTRACT FROM AUTHOR]

Chrysanthemum tea infusions are famous and nutritious beverages worldwide. The results showed that numerous negatively charged spherical particles of 60–1000 nm in diameter generally existed in all chrysanthemum tea infusions prepared from 9 kinds of chrysanthemums for tea use. Taking Chrysanthemum morifolium ' Hangbaiju ' tea infusion as an example, crushing, heating and increasing flower-to-water ratio were three strategies to prepare optimal submicroparticles with the smallest mean hydrodynamic diameter as 288.40 nm and polydispersity index as 0.25. The submicroparticles were stable when temperature change, dialysis, centrifugation, storage, pH change (2–9) and ionic strength change were applied but unstable when freeze-thaw, lyophilization, ultrafiltration, concentration and pH change (10) were applied. Polysaccharides and phenolics were dominant components of submicroparticles which were maintained by hydrogen bonds and hydrophobic interactions among polysaccharides and phenolics. This study provided a novel perspective to decipher and control supramolecular aggregation in chrysanthemum tea infusions for rational manufacturing. [Display omitted] • Submicroparticles in 9 kinds of chrysanthemum tea infusions were characterized. • Three strategies for preparing small and uniform submicroparticles were reported. • Physicochemical factors affected stability of submicroparticles were discovered. • The submicroparticles dominantly formed by polysaccharides and phenolics. • Hydrogen bonds and hydrophobic interactions maintained submicroparticles. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work was to conduct an activity-guided isolation of antibacterial compounds from Rabdosia serra. The ethanol extracts of R. serra leaf and stem were partitioned sequentially into petroleum ether, ethyl acetate, butanol and water fractions, respectively. The ethanol extract of leaf evidenced broad-spectrum antibacterial activity against Gram-positive bacterial, including Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Listeria monocytogenes. The ethyl acetate fractions of leaf and stem exhibited strong inhibition against Gram-positive bacteria, and were then purified further. On the basis of antibacterial assay-guided purification, three phenolic compounds (rosmarinic acid, methyl rosmarinate and pedalitin) and four C-20 oxygenated ent-kauranes (effusanin E, lasiodin, rabdosichuanin D and a new compound namely effusanin F) were obtained, whose contents were determined by HPLC analysis. The broth microdilution method confirmed the important inhibition potential of C-20 oxygenated ent-kauranes with low minimum inhibitory concentration (MIC) values. Effusanin E, lasiodin and effusanin F could be useful for the development of new antibacterial agents. [Copyright &y& Elsevier]

Abstract: Volatiles in Rabdosia serra were investigated by headspace solid phase microextraction (HS-SPME) and simultaneous–distillation extraction (SDE). The HS-SPME technique was previously evaluated to optimise sampling conditions. A total of 56 and 48 compounds including alcohols, aldehydes, hydrocarbons, ketones, carboxylic acid, ester, and aromatics were identified in leaf and stem by optimised HS-SPME method (CAR/PDMS fibre; incubation time, 10min; extraction temperature, 50°C; extraction time, 40min), respectively. 1-Octen-3-ol and (2E)-hexenal had significant contribution to R. serra aroma. Cluster analysis indicated that leaf and stem exhibited different volatile diversity. Air drying was favourable for the retention of the volatiles, while freeze- and sun-drying led to the loss of volatiles. SDE method preferred to the analysis of compounds with low volatility including fatty acids and esters. HS-SPME was a useful technique for the analysis of readily volatile components for the characteristics of R. serra aroma. [Copyright &y& Elsevier]

Abstract: 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 &y& Elsevier]

Abstract: Inactivation kinetics of peroxidase and polyphenol oxidase in fresh Rabdosia serra leaf were determined by hot water and steam blanching. Activation energy (52.30kJmol−1) of polyphenol oxidase inactivation was higher than that (20.15kJmol−1) of peroxidase. Water blanching at 90°C or steam blanching at 100°C for 90s was recommended as the preliminary treatment for the retention of phenolics. Moreover, comparative evaluation of drying methods on the phenolics profiles and bioactivities of R. serra leaf were conducted. The results indicated that only intact leaf after freeze drying retained the initial quality. The sun- and air-dried leaves possessed identical phenolic profiles. The homogenised leaf (after freeze-drying) possessed a lower level of phenolics due to enzymatic degradation. Good antioxidant activities were detected for the sun- and air-dried leaves. There was insignificant difference in anti-tyrosinase and anti-α-glucosidase activities among sun-, air-, and freeze-dried leaves. [Copyright &y& Elsevier]

Abstract: A phytochemical investigation was conducted on Rabdosia serra leaf in this work. A new ent-kaurane-type diterpenoid named 6β,14α-dihydroxy-1α,7β-diacetoxy-7α,20-epoxy-ent-kaur-16-en-15-one, together with 6 known compounds were identified, including parvifolin G, effusanin E, lasiodin, nodosin, β-sitosterol, and stigmasterol. It was the first time that parvifolin G and effusanin E were found in R. serra. The assay of inhibition activity against HepG-2, MCF-7, and HL-60 cell lines indicated that 10 compounds (including rosmarinic acid, methyl rosmarinate and pedalitin which were isolated previously), except parvifolin G and stigmasterol, exhibited cytotoxicity against the tested tumour cells. The tumour inhibitory effects of ent-kaurane-type diterpenoids (except parvifolin G) were more effective than those of sterols and phenolics. Both 6β,14α-dihydroxy-1α,7β-diacetoxy-7α,20-epoxy-ent-kaur-16-en-15-one and lasiodin (IC50 <5μM) displayed strong cytotoxicity against the tested tumour cells, indicating the potential for new chemotherapeutic drugs. [Copyright &y& Elsevier]

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 the present study, various lotus leaf extracts were prepared by multiple methods, characterized by 12 alkaloids, 14 flavonoids, and superoxide anion radical scavenging (OS) and xanthine oxidase inhibitory (XOI) activities, and divided into 3/4 groups with different characteristics. Both alkaloids and flavonoids contributed to XOI activity of representative lotus leaf extract. Norcoclaurine, O -nornuciferine, N -nornuciferine, nuciferine, luteolin, diosmetin, quercetin, and quercetin-3- O -glucuronide were defined as quality control standards for lotus leaf extracts with dual OS and XOI activities. Enzymatic hydrolysis coupled with ultrasound-assisted extraction method using 50% (v/v) ethanol was the most favorable approach for preparing food-grade lotus leaf extract with dual functions. Network pharmacology revealed that this extract having abundant alkaloids and flavonoids (especially flavonoid aglycones) could improve hyperuricemia by multiple actions on uric acid synthesis and transport, inflammation response, oxidative stress and lipid metabolism. Our study provided crucial data about clear quality control standards for plant-based functional food with potential hypouricemic effect. [Display omitted] • Antioxidant and XOI activities of various lotus leaf extracts were characterized. • It was the first time that hesperetin had been identified in lotus leaf. • Lotus leaf extracts were classified via chemical compositions and dual functions. • Lotus leaf extract with dual functions had potential hypouricemic effect. • Quality control standards for lotus leaf-based hypouricemic food were confirmed. [ABSTRACT FROM AUTHOR]

• Volatiles and phenolics of 31 batches of C. morifolium ' Boju ' were characterized. • Minority of ' Boju ' had abundant monoterpenoids and flavonoid aglycones. • Xanthine oxidase inhibitory effect-related phenolics and volatiles were screened. • Three flavonoid aglycones were identified as quality control standards of ' Boju '. • Four key monoterpenoids were identified as quality control standards of ' Boju '. This study aimed at obtaining precise quality control standards to efficiently screen Chrysanthemum morifolium Ramat. ' Boju ' with strong xanthine oxidase (XO) inhibitory activity for developing C. morifolium ' Boju ' extract based-hypouricemic functional food. The results indicated significant differences in volatile and phenolic profiles and XO inhibitory (XOI) activities of 31 batches of C. morifolium ' Boju ' collected in herb/tea market. The minority of C. morifolium ' Boju ' having abundant characteristic monoterpenoids and flavonoid aglycones showed strong XOI activities, while the majority of C. morifolium ' Boju ' possessing few corresponding monoterpenoids and flavonoid aglycones exhibited moderate XOI activities. Seven XOI activity-directly related phenolics and ten XOI activity-indirectly related volatiles were identified by UPLC-ESI-QTOF/MS-based and HS-SPME-GC/MS-based spectrum-effect relationships, respectively. Three flavonoids (luteolin, apigenin and acacetin) identified as key XO inhibitors and four monoterpenoids (filifolone, α-terpineol, thymol and piperitenone) closely related to key XO inhibitors were screened for XOI activity-oriented quality control of C. morifolium ' Boju '. [ABSTRACT FROM AUTHOR]

• A peptide fraction was prepared from a low-edible-value sea cucumber. • S. variegates peptide fraction possessed desired color and low viscosity. • S. variegates peptide exhibited good resistance against citric acid-heat treatment. • S. variegates peptide fraction effectively promoted longevity in fruit flies. • S. variegates peptide fraction effectively attenuated oxidative injury in mice. Sea cucumber-derived peptide, a potential candidate for combating aging, is currently under-developed. In the present study, we reported the development of a green approach to efficiently prepare a high-value anti-aging oligopeptide fraction with desired color and low viscosity from a low-edible-value sea cucumber (Stichopus variegates) containing highly viscous polysaccharide using enzymatic hydrolysis, acid-heat treatment and ultrafiltration. The analysis by UPLC-MS/MS revealed the peptide composition characteristic of S. variegates peptide fraction, suggesting the acceptable stabilities of oligopeptides during citric acid-heat processing. In vivo studies demonstrated that S. variegates peptide fraction effectively promoted longevity in normal and D-galactose-induced aging fruit flies and attenuated D-galactose-induced oxidative injury in mice via up-regulating Klotho expression, activating SOD and GSH-Px, and inhibiting lipid peroxidation and protein oxidation. Our results also validated the stability of longevity promoting efficacy and anti-oxidative stress action of S. variegates peptide after citric acid-heat treatment. [ABSTRACT FROM AUTHOR]

Flavonoids have a variety of bioactivities, but their poor solubility, low bioavailability, and weak stability limit their application as functional factors in food systems. Soy extracts (SE) mainly composed of soy proteins and soluble polysaccharides at mass ratios of 4.1–5.8: 1 and possessing good bioactivity and nutritional property might be candidate functional encapsulation carriers to improve defects of flavonoids and enhance overall nutritional quality. In this study, galangin (Gal), a poorly water-soluble flavonoid, was used as an example to evaluate the application potential of SE in flavonoid delivery system. Gal-loaded SE nanoparticles (Gal-loaded SE NPs) with high Gal solubility, encapsulation efficiency and bioaccessibility were successfully constructed by pH-driven method. The solubilizing effect of SE on Gal largely depended on the concentrations of SE and Gal. Combining the encapsulation efficiency and retention rate, the optimal conditions were identified as SE concentration of 40 mg/mL, binding time of 5 min, and Gal to SE mass ratio of 1%. Gal-loaded SE NPs showed good storage, thermal, redissolution, and sodium ions stabilities. Based on Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscope analysis, the proteins in SE might undergo a typical de-folding and re-folding process during pH-shifting and mainly combine with Gal by hydrophobic interaction to form Gal-loaded SE NPs with spherical shape (particle diameter <100 nm). This study broadened the application of SE in flavonoid delivery system and provided new ideas for the design and development of new plant-based health food ingredients with multiple functional factors and high nutritional quality. [Display omitted] • Soy lipid-lowering extracts (SE) were used as carriers for galangin (Gal). • Gal loaded SE nanoparticles (Gal-loaded SE NPs) were constructed. • Gal-loaded SE NPs had high encapsulation efficiency. • Gal-loaded SE NPs showed good solubility, stability, and bioaccessbility. • Gal-loaded SE NPs might be mainly formed by hydrophobic interaction. [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]

In this study, the performance and separation characteristics of four macroporous resins for purifying umami peptides from soy sauce were examined. Results showed that the resins could separate the peptides of soy sauce, and the particle diffusion kinetics model was suitable for describing the whole exothermic (Δ H < 43 kJ/mol) adsorption process on the SP-825 and HP-20 resins, while the pseudo -second-order kinetics model accurately described the XAD-16 and HP-2MGL resins. Furthermore, the adsorption processes of the peptides followed the Freundlich model. The XAD-16 resin was the most effective resin for the enrichment of peptides due to its high adsorption and total desorption capacities. Interestingly, the umami peptides were enriched in the deionized water fraction. This study provides new insights into exploring performance and separation characteristics of macroporous resins on soy sauce, and indicated that peptide may be the contributor to the umami taste in Chinese soy sauce. [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]

Sargassum fusiforme polysaccharides (SFPs), including SFP-3-40, SFP-3-60, SFP-3-80, SFP-7-40, SFP-7-60, SFP-7-80, SFP-10-40, SFP-10-60, and SFP-10-80, were extracted at different pH (3, 7, and 10), and then precipitated with graded precipitation of 40%, 60% and 80% (v /v) ethanol solution, respectively. Their physicochemical properties and α -glucosidase inhibitory activity were determined. Results showed that SFPs significantly differed in the contents of total sugar, protein, uronic acid, sulfate, the zeta potential, and molecular weight distribution. SFPs, including SFP-10-40, SFP-10-60, and SFP-10-80, had bigger absolute zeta potential value and higher respective average molecular weight in the same ethanol concentration precipitate. All samples were mainly composed of fucose, glucuronic acid, and mannose with different molar ratios. The extraction pH and precipitation ethanol solution concentration caused little changes in functional groups, but significantly altered surface morphology of SFPs. Congo red test revealed that all polysaccharides were not helical polysaccharides. Rheological measurements indicated that SFPs were pseudoplastic fluids and showed elastic behavior of the gel. Except SFP-3-40 and SFP-3-60, all other samples had a stronger α -glucosidase inhibitory activity than that of acarbose. The inhibition type of SFPs against α -glucosidase varied owing to different extraction pH and precipitation ethyl concentration. This study shows that extraction pH can significantly affect the structure and hypoglycemic activity of SFPs and provide a data support for the scientific use of Sargassum fusiforme in industrial production. [Display omitted] • Nine polysaccharide fractions were obtained from Sargassum fusiforme (Harv.) Setch at different extraction pH. • The physicochemical properties of SFPs were significant different. • SFP-7-40 showed the strongest α -glucosidase inhibitory activity with IC 50 values of 0.304 mg/mL. [ABSTRACT FROM AUTHOR]

The objective of present research was to explore whether Sargassum fusiforme polysaccharide (SFP) could partly replace acarbose against type 2 diabetes in rats. Results indicated that SFP co-administered with low-dose acarbose intervention typically mitigated diabetic symptoms and serum profiles and exhibited better anti-diabetic effects than single acarbose treatment in controlling fasting blood glucose, improving insulin resistance and mitigating kidney injuries. The RT-qPCR analysis indicated that SFP co-administered with low-dose acarbose administration distinctly activated the IRS/PI3K/AKT signaling pathway compared with single acarbose treatment. Moreover, the co-administration also restrained liver fat accumulation via affecting the expression of HMGCR and SREBP-1c genes. In addition, the 16S rRNA gene sequencing analysis indicated that SFP co-administered with low-dose acarbose significantly restored beneficial composition of gut flora in diabetic rats, such as the increase of Muribaculaceae , Lachnospiraceae , Bifidobacterium , Ruminococcaceae _UCG-014, Ruminococcus _1, Romboutsia , Eggerthellaceae , Alistipes and Faecalibaculum , and the decrease of Escherichia - Shigella. These results suggested that SFP, the novel natural adjuvant of acarbose, displayed the desirable benefits in minimizing the dose of drug, while improving the anti-diabetic efficiency. Unlabelled Image • SFP-ACAR typically mitigated diabetic symptoms and serum profiles. • SFP-ACAR showed better effects in controlling FBG, insulin, BUN and Cr levels. • SFP-ACAR distinctly restored beneficial composition of gut flora in diabetic rats. • SFP-ACAR improved IR by notably activating the IRS/PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]