•Sargassum pallidum polysaccharides were fractioned to obtain four fractions.•Preliminary structural features of four polysaccharide fractions were determined.•The bioactivities of four polysaccharide fractions were compared.Sargassum pallidum polysaccharides were fractioned using a DEAE-Sepharose fast-flow column and four polysaccharide fractions (SP-P1, SP-P2, PV-P3 and SP-P4) were obtained. Structural analyses indicated that SP-P2 and SP-P4 had higher molecular weights than SP-P1 and SP-P3. SP-P2, SP-P3 and SP-P4 comprised of fucose, rhamnose, arabinose, galactose, glucose, xylose, and mannose in a similar molar ratio, while SP-P1 did not contain arabinose. SP-P2 and SP-P4 had a similar number of (1 → 6) or (1→) glycosidic linkages (1 → 2) or (1 → 4) glycosidic linkages and (1 → 3) glycosidic linkages, while SP-P1 and SP-P3 contained a small number of (1 → 3) glycosidic linkages. SP-P2 exhibited better bioactivities than SP-P1, SP-P3 and SP-P4, including antioxidant, anti-hemolysis inhibitory, α-amylase and α-glucosidase inhibitory and antiproliferative activities. These data suggest that S. pallidum has four polysaccharide fractions with different structural features and bioactivities and SP-P2 has potential to be explored as a functional food or complementary medicine.

•Mulberry fruit polysaccharides with different molecular weight were fractioned.•The chemical characters, morphology and thermogravimetric properties were determined.•The impact of polysaccharides on lipid oxidation under digestion model was studied.•The MFP-2 had the strongest ability reducing the rate and extent of lipid digestion.Three polysaccharides (MFP-1, MFP-2, and MFP-3) were fractioned from mulberry fruits with 30%, 60%, and 90% (v/v) ethanol, respectively. The MFP-1 had the largest molecular weight of 838 kDa, followed by MFP-2 from 49.5 to 163 kDa, and then MFP-3 from 1.41 to 15.30 kDa. The three polysaccharides were composed of arabinose, galactose, glucose, mannose, xylose, and galacturonic acid but with different molar ratio. They also exhibited different surface morphology and thermogravimetric properties. In addition, the impact of the three polysaccharides on the digestion of lipid in a simulated saliva and gastrointestinal tract was investigated. The results indicated MFP-2 had the strongest ability to reduce the rate and extent of lipid digestion. These results have important implications for understanding the influence of polysaccharides on lipid digestion. The effect on retarding lipid digestion within the gastrointestinal tract might be important for the development functional food rich in oil to promote health.

•Microwave-assisted extraction of Sargassum thunbergii polysaccharides was built.•Extraction parameters for the polysaccharides yield were optimized by RSM.•Physicochemical properties and primary structure of STP-1 were investigated.•STP-1 could be exploited as an effective antioxidant and hypoglycemic agent.In the present work, optimization of microwave-assisted extraction of polysaccharides from Sargassum thunbergii was investigated. The physicochemical properties, structural characteristics, and in vitro antioxidant and hypoglycemic activities were determined. The optimal extraction conditions with a yield of 2.84 ± 0.09% for extraction of polysaccharides (STP-1) were extraction time 23 min, microwave power 547 W, extraction temperature 80 °C, and the ratio of raw material to water 1:27 g/mL. STP-1 contained 32.7% of total carbohydrate, 1.86% of protein, and 15.2% of sulfates. STP-1 had a major molecular weight of 190.4 kDa, and comprised of arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid with molar percentages of 1.94, 30.7, 4.54, 23.2, 17.6, 8.11, and 13.9%, respectively. In addition, STP-1 showed strong antioxidant and α-glucosidase inhibitory activities, and could improve the glucose uptake in insulin-resistant HepG2 cells, suggesting that STP-1 can be exploited as a promising natural antioxidant and hypoglycemic agent.

Mulberry fruit polysaccharide (MFP), one of the major active ingredients isolated from the mulberry fruit, possesses numerous bioactivities. In vitro hypoglycemic experiments showed that MFP had significant insulin-sensitizing activity through increasing insulin secretion and promoting pancreatic β cell proliferation. In vivo, the oral administration of MFP could significantly decrease blood glucose levels and increase body weight loss in streptozotocin (STZ)-induced diabetic mice. MFP also significantly decreased the level of malondialdehyde (MDA) and increased the activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) in the liver in STZ-induced diabetic mice. And histopathological examination showed that MFP could markedly alleviate damage to pancreas, liver and kidney tissue in STZ-induced diabetic mice. This study suggested that MFP had antioxidant and hypoglycemic properties and could provide a protective effect on STZ-induced diabetic mice.

•Mulberry polyphenols were fractionated through gradient ethanol elution.•UHPLC-MS/MS identified and quantified 47 phenolic compounds, including 21 new ones.•Antioxidant activity and anti-diabetic potential were analyzed in vitro & ex vivo.•Hierarchical cluster and correlation analysis reveal contributors to bioactivities.•Dihydroquercetin & 1,5-dicaffeoylquinic acid contribute to anti-diabetic potential.To explore the comprehensive phenolic profile of mulberry (Morus alba L.) fruit and reveal the novel anti-diabetic constituents, mulberry polyphenols (MP) were fractionated through gradient ethanol elution and subjected to composition and bioactivity analysis. Forty-seven phenolic compounds were identified and quantified through UHPLC-HR-ESI-TOF-MS/MS, including twenty-one newly identified compounds such as delphinidin 3-rutinoside-5-glucoside and cyanidin 3-rutinoside dimer. The antioxidant activity and anti-diabetic potential of fractionated MP were analyzed in vitro and ex vivo with HepG2 and pancreatic β-cell RIN-m5F. Hierarchical cluster analysis and Pearson correlation coefficients revealed compounds such as syringic acid and galloylcyanidin-glycoside contributed most to inhibit α-glucosidase activity. Quercetin and cyanidin-glycosides were essential for cellular antioxidant activity. Dihydroquercetin and 1,5-dicaffeoylquinic acid were newly identified and validated as the main contributors after rutin to protect RIN-m5F cells against glucotoxicity. Such findings suggest the promising role of MP for type II diabetics and lay the foundation of further utilization and investigation.Download high-res image (224KB)Download full-size image

•Microwave-assisted extraction was used for polysaccharide extraction from Moringa oleifera Lam. leaves.•Three polysaccharide fractions with different molecular weight were obtained from Moringa oleifera Lam. leaves.•The rheological properties of different polysaccharide fractions were investigated.•The MLP-3 showed good hypoglycemic activity in vitro.Microwave-assisted extraction of Moringa oleifera Lam. leaf polysaccharides was investigated using a response surface methodology. The following conditions were found to generate an experimental yield of 2.96 ± 0.11%, which closely agreed with the predicted value of 2.89%: time 70 min, microwave power 700 W, temperature 70 °C and a liquid/solid ratio of 35 mL/g. After the MLPs were treated with graded precipitation of 40%, 60% and 80% (v/v) ethanol solution, the respective average molecular weight polysaccharide fractions, namely MLP-1 (9.68 × 103 kDa), MLP-2 (6.29 × 103 kDa) and MLP-3 (4.86 × 103 kDa), were obtained. These three fractions were composed of xylose, mannose, glucose, galactose and arabinose but with differing molar ratios. They had similar Fourier transform infrared spectroscopy but their surface morphology differed as determined by scanning electron microscopy. The Congo red assay indicated that the three fractions were not helical polysaccharides. The three polysaccharide fractions exhibited different rheological properties. MLP-1 exhibited pseudoplastic flow behaviors, while MLP-3 displayed near-Newtonian flow behaviors over the entire accessible frequency range. In addition, MLP-3 had stronger inhibitory effects on α-amylase and α-glucosidase than MLP-1 and MLP-2. The results suggest that MLP-3 has potential for the treatment of diabetes.

•Conventional thermal processing might result in degradation of berry polyphenols•Noble thermal processing technologies like microwave & ohmic heating are promising•Pulsed electric field enhance wine extraction & sterilization and juice production•Various membranes are applied to clarify, sterilize, concentrate and deacidify juice•New non-thermal processing like cold plasma & hydrothermodynamic await investigationThe demand from consumer for safe and nutritious berry and berry products has promoted the rapid development of non-conventional processing technologies. This review summarizes the recent advances of thermal and non-thermal processing technologies in berry and berry products, including microwave, ohmic heating, high pressure processing, irradiation, dense phase carbon dioxide, ultrasonic processing, pulsed electric field, ozone, membrane processing technologies, cold plasma, and hydrothermodynamic cavitation. These technologies individually or in combination have shown great potential for extraction, sterilization, drying, concentration and deacidfication. They could decrease processing time and temperature, improve processing efficiency and minimize nutritional losses, as well as reduce energy consumption. Given the nutritional benefits of anthocyanins and other polyphenols in berry, their content and compositional change during processing were highlighted, as well as the primarily studies of the underlying mechanisms. The advantage and limitation of these technologies are also discussed along with the perspective insight of their future development.Download high-res image (218KB)Download full-size image

•The structural parameters of microemulsion were studied by dilution experiment.•The formation of W/O microemulsion was confirmed by conductivity measurement.•Starch nanoparticles were prepared by W/O microemulsion-cross-linking methods.•The properties of starch nanoparticles were studied by SEM, DLS, XRD and FTIR.•The drug loading and releasing properties of starch nanoparticles were studied.In this research, 1-hexadecyl-3-methylimidazolium bromide C16mimBr/butan-1-ol/cyclohexane/water ionic liquid microemulsion was prepared. The effects of n-alkyl alcohols, alkanes, water content and temperature on the properties of microemulsion were studied by dilution experiment. The microregion of microemulsion was identified by pseudo-ternary phase diagram and conductivity measurement. Then starch nanoparticles were prepared by water in oil (W/O) microemulsion-cross-linking methods with C16mimBr as surfactant. Starch nanoparticles with a mean diameter of 94.3 nm and narrow size distribution (SD = 3.3) were confirmed by dynamic light scattering (DLS). Scanning electron microscope (SEM) data revealed that starch nanoparticles were spherical granules with the size about 60 nm. Moreover the results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) demonstrated the formation of cross-linking bonds in starch molecules. Finally, the drug loading and releasing properties of starch nanoparticles were investigated with methylene blue (MB) as drug model. This work may provide an efficient pathway to synthesis starch nanoparticles.

A novel polysaccharide (MFP3P) was isolated from Murus alba L. through the hot water extraction method followed by chromatographic purification. The chemical structure of MFP3P was elucidated by acid hydrolysis, Smith degradation and methylation analysis, along with FT-IR, GC-MS, 1H and 13C NMR spectroscopy. Its morphological properties were further characterized by SEM and AFM. The selenide of the polysaccharide (MFP3P-Se) was obtained by the Na2SeO3/BaCl2 method. The antioxidant properties showed that MFP3P-Se exhibited higher peroxy radical-scavenging capacity than MFP3P in vitro. Moreover, MFP3P-Se had more significant hypoglycemic effects than MFP3P through promoting pancreatic cell proliferation and increasing glucose metabolism and insulin secretion.

The present study aimed to characterize and investigate the polysaccharide fractions of mulberry fruit, and their antioxidant and hypoglycemic activities. Mulberry fruit polysaccharides (MFP) were extracted by using hot water as the solvent and fractioned by using a DEAE-Sepharose fast-flow column. In total four eluents of water (MFP-1), 0.1 M NaCl (MFP-2), 0.2 M NaCl (MFP-3) and 0.3 M NaCl (MFP-4) were fractionated. Arabinose, galactose, glucose, xylose and mannose were the main components present in MFP-1, while MFP-2 and MFP-3 were composed of arabinose and galactose, and MFP-4 of arabinose, galactose and glucose. High-performance gel permeation chromatography (HP-GPC) analysis indicated a narrower molecular weight distribution in the MFP-1 fraction. Scanning electron microscopy (SEM) exhibited a smooth surface for MFP-1 and MFP-3 fractions, whereas MFP-2 and MFP-4 have pore openings and flocculent fibers on a smooth surface. Tertiary structure analyses indicated that none of the fractions had a triple-helical conformation. On the whole, MFP-3 and MFP-4 showed better antioxidant activity and inhibitory effects on α-amylase and α-glucosidase compared to MFP-1 and MFP-2. These results show significant potential for the antioxidant and hypoglycemic activities of MFP-3 and MFP-4 indicating the need for their further exploration as potential antidiabetic agents.

Mulberry (Morus indica L.) fruits are rich sources of polyphenols with multiple health benefits. The gear juicer and colloid mill were compared in mulberry juice production and further marc water extraction based on polyphenol yield, phytochemical profiles, bioactivities, as well as microstructure of residues. Higher content of phenolic compounds, stronger antioxidative, and α-Glucosidase inhibition activities were obtained in colloid mill-processed juice. The extraction kinetics of marc was investigated under three conditions (stirring, ultrasound, and combined stirring and ultrasound) at 25 °C for 2.5 h. Based on total polyphenol and monomeric anthocyanin yield, the optimum extraction condition for gear juicer marc was combination of ultrasound with stirring for half an hour. While ultrasound for 1 h was optimized for water extraction of colloid mill marc. Using the optimized extraction condition, total polyphenols and monomeric anthocyanin obtained from colloid mill-processed samples, including juice and marc extract, were approximately 46 and 68 % higher than those in gear juicer-processed samples. Compared to gear juicer, colloid mill processing generated smaller particle size and more disrupted microstructure, which contributed to higher content of phenolic compounds in colloid mill juice. Moreover, changes in the microstructure of mulberry marc were intensified by extraction conditions, which improved polyphenol extraction efficiency, especially for colloid mill marc. These results provided valuable information for comparing gear juicer and colloid mill in mulberry as well as other berries for juice production and marc water extraction, and emphasized the great potential of colloid mill in berry processing.

The adsorption performance of color compounds in sugar juice was investigated using modified sugarcane bagasse as an adsorbent. The adsorption of color compounds was investigated at different operating conditions including adsorbent dosage, pH, and contact duration. Three kinetic models and two isotherms were applied to describe the adsorption process and evaluate the adsorption equilibrium, respectively. Results showed that the adsorption was optimum at an adsorbent dosage of 0.05 g/mL and at pH 5 for 30 min, which yielded 59.18 % of decolorization rate. Adsorption kinetics indicated that the process followed the pseudo-second-order chemisorption model. The adsorption behavior was well described by the Freundlich isotherm model, showing a multilayer capacity for color compounds. Moreover, the regeneration studies showed the adsorbent had a good reuse performance over several regeneration cycles. These results suggest that the modified sugarcane bagasse is an inexpensive and efficient adsorbent, which has potential application for removing color compounds from sugar juice.

A new heteropolysaccharide, here called P1, was isolated from the fruit clusters of Prunella vulgaris using a hot water extraction method. Chemical and physical analyses indicated that P1 had a spherical conformation with an average molecular weight of 1750 kDa and consisted of arabinose (28.37%), xylose (54.67%), mannose (5.61%), glucose (5.46%), and galactose (5.89%). The main types of P1 linkages were proved to be (1→5)-linked α-L-Ara, (1→)-linked α-L-Ara, (1→3)-linked α-D-xyl, (1→3)-linked β-D-Gal, (1→3,6)-linked β-D-Gal, (1→3,6)-linked α-D-Man and (1→6)-linked α-D-Glc according to the periodate oxidation-Smith degradation and NMR analyses. P1 could significantly enhance the secretion of NO, TNF-α, and IL-6 in murine RAW 264.7 cells, involving the toll-like receptor 2 (TLR2), TLR4 and complement receptor 3 (CR3). Further studies showed that P1 exhibited stable immune activities in the pH range of 4.0–10.0 and below 121 °C. The results suggested that P1 could be used as a potent immunomodulatory agent in functional foods and pharmacological fields.

In this study, debranched-starch/phosphatidylcholine inclusion complexes were prepared. The effect of reaction parameters such as reaction temperature, reaction time, and addition amount of phosphatidylcholine on the phosphatidylcholine payload and inclusion rate was investigated. The phosphatidylcholine payload and inclusion rate prepared under the optimal conditions were 106 mg/g and 84.8%, respectively. The formation of debranched-starch/phosphatidylcholine inclusion complexes was confirmed by the results of XRD and FT-IR. Furthermore, the molecular, cluster, and fractal structures of the complexes were investigated using 13C CP/MAS NMR and SAXS. The results indicated that the inclusion complexes were formed by hydrophobic interactions between alkyl chain of phosphatidylcholine and debranched-starch helix cavity. The complexes possessed a mass fractal structure, and a semicrystalline structure with a Bragg distance of 19.04 nm formed. After complexation, the stability of phosphatidylcholine was significantly improved, and phosphatidylcholine of the complexes can be gradually released with pancreatin treatment. This study revealed that debranched-starch can be used as an effective carrier of phosphatidylcholine for the purpose of improving its stability.

Response surface methodology was used to optimize the ultrasonic extraction of Prunella vulgaris polysaccharides (PVP). When the quality of P. vulgaris was 4.0 g, the optimal extraction conditions were ultrasonic power 210 W, time 50 min, and temperature 70 °C. Using this condition, the experimental yield was agreed closely with the predicted value. Compared with conventional extraction, ultrasonic extraction showed a higher polysaccharide yield. The molecular weights were determined by high-performance gel permeation chromatography. Gas chromatography analysis suggested that PVP comprised of rhamnose, arabinose, xylose, mannose, glucose, and galactose with molar percentages of 2.8, 28.2, 38.5, 11.0, 3.0, and 16.5 %, respectively. The glycosidic linkage analysis showed that PVP contained 1→ and 1→6 glycosidic linkages (48.0 %), 1→2 and 1→4 glycosidic linkages (8.1 %), and 1→3 glycosidic linkages (43.9 %). PVP showed good antioxidant activities by the methods of DPPH radical scavenging assay, oxygen radical absorbance capacity assay, and cellular antioxidant activity assay. The antiproliferative activities of PVP (2.0 mg/mL) on the growth of human hepatoma HepG2, gastric carcinoma SGC 901, and human breast cancer MCF-7 cells were 51.2, 35.2, and 31.8 %, respectively. PVP did not exhibit cytotoxicity against normal liver L02 cells within the tested concentrations. These results demonstrated that polysaccharides isolated from P. vulgaris may be helpful to develop potential antioxidant and antitumor agents for food and pharmaceutical industries.

An ionic liquid microemulsion consisting of 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF6), surfactant TX-100, 1-butanol, and water was prepared. The water-in-[Bmim]PF6 (W/IL), bicontinuous, and [Bmim]PF6-in-water (IL/W) microregions of the microemulsion were identified by conductivity measurements. Starch nanoparticles with a mean diameter of 91.4 nm were synthesized with epichlorohydrin as cross-linker through W/IL microemulsion cross-linking reaction at 50 °C for 4 h. Fourier transform infrared spectroscopy (FTIR) data demonstrated the formation of cross-linking bonds in starch molecules. Scanning electron microscopy (SEM) revealed that starch nanoparticles were spherical and that some particles showed aggregation formation. Furthermore, drug loading and releasing properties of starch nanoparticles were investigated with mitoxantrone hydrochloride as a drug model. This work provides an efficient and environmentally friendly approach for the preparation of starch nanoparticles, which is beneficial to their further application.

Phosphorylated amphoteric starch was prepared from enzyme-modified tapioca starch in the aqueous alcoholic–alkaline medium. Optimization of the reaction parameters for maximum degree of substitution (DS) of phosphorylated amphoteric starch were carried out using response surface methodology (RSM). Optimum modification conditions were shown as following: NaOH concentration 3.71 g/100 g starch (dry basis), CHPTAC concentration 6.34 mL/100 g starch (dry basis), STP concentration 6.13 g/100 g starch (dry basis), water/ethanol ratio 1.16, reaction temperature 50 °C, reaction time 3 h, and the starch concentration 30%. Under the optimal condition, the maximum anion degree of substitution (DSA) and cation degree of substitution (DSC) were 0.0274 and 0.0408, respectively. Compared with the DS of the amphoteric starch prepared from native tapioca starch (NPTAS), the DS of the amphoteric starch from enzyme-pretreated tapioca starch (EPTAS) was higher at the same reaction conditions, suggesting enzymatic pretreatment improved the reaction processes significantly. Scanning electron microscopy and X-ray diffraction data showed that the granular shape and crystalline structure of EPTAS did not change. Compared with NPTAS, the pasting stability of EPTAS with the same DS was also significantly improved.Highlights► Phosphorylated amphoteric starch was prepared from enzyme-modified starch. ► The optimum reaction parameters were studied using response surface methodology. ► Enzymatic pretreatment improved the reaction processes significantly. ► The pasting stability of amphoteric starch from enzyme-pretreated tapioca starch was improved.

Lipase-catalyzed synthesis of starch palmitate was investigated in ionic liquid mixtures consisting of 1-butyl-3-methyl-imidazolium acetic ([BMIm]Ac) and 1-butyl-3-methyl-imidazolium tetraflouroborate ([BMIm][BF4]). The effect of reaction parameters such as the amount of enzyme used, the reaction temperature, the mass ratio of [BMIm][BF4]/[BMIm]Ac, the molar ratio of methyl palmitate/anhydroglucose unit in starch, and the reaction time on the degree of substitution was studied. The formation of starch esters was confirmed by the presence of the carbonyl signal in the FT-IR and NMR spectra. Scanning electron microscopy and X-ray diffraction data showed that the morphology and crystallinity of starch esters were largely disrupted. Thermogravimetric analysis suggested thermal stability of starch palmitate decreased compared to native starch. Water contact angle measurements revealed that the hydrophobicity of starch esters was improved after modification. The successful lipase-catalyzed synthesis of starch palmitate in ionic liquids suggested that ionic liquids could be used as a potentially attractive green alternative to harmful organic solvents for synthesis of high fatty acid starch ester.

Resonance light scattering (RLS) spectra were used to study the formation of complexes of carboxymethyl cellulose (CMC) and polylactic acid (PLA) in a mixed solvent of 10% DMSO/90% H2O(V/V). The RLS results showed that the CMC and PLA could form a steady homogeneous complex due to the interaction of hydrogen bonding. With the increasing of CMC mass fraction in the complex, the observed durative enhancement RLS signal with two inflexion points indicated the forming of complexes and aggregation of complexes. The aggregation equilibrium and thermo stability of the complexes were also investigated based on RLS values.

•The phenolic compounds of bagasse were identified by UHPLC-HR-TOFMS.•The biological activities of bagasse phenolic extracts were investigated.•Bagasse would be helpful in agents discovery and agro-industrial revenue increase.Sugarcane bagasse, one of the most abundant agro-food by-products, is a very promising raw material available at low cost for recovering bioactive substances. In this study, the total phenolic content was measured by Folin-Ciocalteu method and the antioxidant activity of the extracts was determined by DPPH, ABTS+ and ROO (ORAC) methods. The results indicated that 30% hydroalcoholic fraction (30%E) had the highest total phenolic content (170.68 ± 3.25 mg GAE/g DW) among the hydroalcoholic extracts and was the most active fraction in antioxidant activity. Besides, intestinal α-glucosidase inhibitory activity was conducted to assess the antihyperglycemic ability of the extracts and 30%E showed a significant effect at 10 mg/mL (82.64% inhibition of sucrase and 74.26% inhibition of maltase, respectively). Glucose uptake assay based on HepG2 cells was used to evaluate the glucose uptake effect of 30%E. Five phenolic compounds (tricin 4-O-guaiacylglyceryl ether-7-O-glucopyranoside, genistin, p-coumaric acid, quercetin and genistein) were identified in 30%E using UHPLC-HR-TOFMS. Taken together, the data indicated that sugarcane bagasse can be used as a potential source of bio-active phenolics and may play a role in functional agents exploitation and agro-industrial revenue increase.Download high-res image (131KB)Download full-size image