Effect of baking on the structure and bioavailability of protein-binding zinc from oyster (Crassoetrea hongkongensis).

To compare the bioavailability of protein-binding zinc, we investigated the impact of baking on the structure of zinc-binding proteins. The results showed that zinc-binding proteins enriched in zinc with relative molecular weights distributed at 6 kDa and 3 kDa. Protein-binding zinc is predisposed to separate from proteins' interiors and converge on proteins' surface after being baked, and its structure tends to be crystalline. Especially -COO, -C-O, and -C-N played vital roles in the sites of zinc-binding proteins. However, baking did not affect protein-binding zinc's bioavailability which was superior to that of ZnSO4 and C12H22O14Zn. They were digested in the intestine, zinc-binding complexes that were easily transported and uptaken by Caco-2 cells, with transport and uptake rates as high as 62.15% and 15.85%. Consequently, baking can alter the conformation of zinc-binding proteins without any impact on protein-binding zinc's bioavailability which is superior to that of ZnSO4 and C12H22O14Zn.

Anti-Inflammatory Activity of Peptides from Ruditapes philippinarum in Lipopolysaccharide-Induced RAW264.7 Cells and Mice.

In our previous study, two peptides with favorable anti-inflammatory effects, Asp-Gln-Thr-Phe (DQTF) and Gly-Tyr-Thr-Arg (GYTR), were screened from Ruditapes philippinarum using an in vitro-in silico strategy. The present study aims to investigate the ameliorative effect of Ruditapes philippinarum peptides (RPPs) on acute inflammation and clarify the potential mechanism through in vitro and in vivo experiments. The anti-inflammatory effects of DQTF and GYTR were verified with a lipopolysaccharide (LPS)-induced RAW264.7 cell acute inflammation model and the anti-inflammatory effect of the enzymatic hydrolysates of Ruditapes philippinarum was explored in vivo using an LPS-induced acute inflammatory injury model in mice. The results show that DQTF and GYTR improved the morphology of LPS-injured cells and decreased the concentrations of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in LPS-induced cells. Moreover, the antioxidant enzyme activity in cells was markedly increased with DQTF and GYTR. The enzymatic hydrolysates of Ruditapes philippinarum were obtained with hydrolysis using pepsin-chymotrypsin-trypsin (PeCTHC) and pepsin-trypsin (PeTHC), respectively. PeCTHC and PeTHC significantly reduced pro-inflammatory cytokines and nitric oxide (NO) in the serum. Additionally, the blood indices and levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and malondialdehyde (MDA) in the livers of mice were markedly improved with RPPs administration. In conclusion, RPPs have preventive and protective effects on acute inflammation, with significant prospects for development in the field of functional foods.

Purification, Characterization, cDNA Cloning, and Bioinformatic Analysis of Zinc-Binding Protein from Magallana hongkongensis.

Oysters contain significant amounts of the zinc element, which may also be found in their proteins. In this study, a novel zinc-binding protein was purified from the mantle of the oyster Magallana hongkongensis using two kinds of gel filtration chromatograms. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that its molecular weight was approximately 36 kDa. The protein identified by the Q-Exactive mass spectrometer shared the highest sequence identity with carbonic anhydrase derived from Crassostrea gigas concerning amino acid sequence similarity. Based on homologous cloning and RACE PCR, the full-length cDNA of carbonic anhydrase from Magallana hongkongensis (designated as MhCA) was cloned and sequenced. The cDNA of MhCA encodes a 315-amino-acid protein with 89.74% homology to carbonic anhydrase derived from Crassostrea gigas. Molecular docking revealed that the two zinc ions primarily form coordination bonds with histidine residues in the MhCA protein. These results strongly suggest that MhCA is a novel zinc-binding protein in Magallana hongkongensis.

Elevated platelet count is associated with decreased mortality from hemorrhagic stroke in hospital: a multi-center retrospective cohort study.

This study aimed to investigate the relationship between platelet count (PC) and mortality in patients with hemorrhagic stroke (HS). The research reviewed data from 10,466 patients hospitalized in 208 hospitals in the United States from January 1, 2014, to December 31, 2015. Of these, 3262 HS patients were included in the primary analysis for those admitted to the intensive care unit (ICU). The average age of these patients was 67.05 years, with 52.79% being male. The median PC was (221.67 ± 73.78) × 109/L. Multivariate logistic regression analysis revealed that PC was a protective factor for mortality in HS patients (OR = 0.98, 95% CI 0.97-1.00, P < 0.05). Additionally, a non-linear association between PC and mortality in HS patients was found using a generalized additive model (GAM) and smooth curve fitting (penalty spline method). For the first time, a recursive algorithm identified the inflection point of platelet count as 194 × 109/L. On the left side of the inflection point, for every increase of 10 units in platelet count, the mortality rate of HS patients decreases by 10%. The study demonstrates a non-linear relationship between PC and the risk of mortality in HS patients. A platelet counts higher than the inflection point (194 × 109/L) may be a significant intervention to reduce mortality in HS patients.

Carboxymethyl cellulose and carboxymethyl chitosan-based composite nanogel as a stable delivery vehicle for oyster peptides: Characterization, absorption and transport mechanism.

An oyster peptide (OPs)-loaded composite nanogel based on carboxymethyl cellulose and carboxymethyl chitosan (CMC@CMCS@OPs) was prepared, and the characterization, absorption and transport mechanism were further investigated. CMC@CMCS@OPs, a dense spherical microstructure with a diameter of ∼64 nm, which enhanced the thermal and digestive stabilities of individual OPs and improved its retention rate of hypoglycemic activity in vitro. The swelling response and in-vitro release profiles showed that CMC@CMCS@OPs could help OPs achieve targeted and controlled release in the intestine. In addition, CMC@CMCS@OPs had no cytotoxicity on Caco-2 cells, and its apparent permeability coefficients increased 4.70-7.45 times compared with OPs, with the absorption rate increased by 129.38 %. Moreover, the transcytosis of CMC@CMCS@OPs nanogel occurred primarily through the macropinocytosis pathway, endocytosis pathway and intestinal efflux transporter-mediated efflux. Altogether, these results suggested that CMC@CMCS@OPs nanogel could be as an effective OPs delivery device for enhancing its stability and absorption.

Optimization of a Novel Tyrosinase Inhibitory Peptide from Atrina pectinata Mantle and Its Molecular Inhibitory Mechanism.

In order to realize the multi-level utilization of marine shellfish resources and to develop the potential biological activity of processing by-products of Atrina pectinata, gelatin was extracted from the mantle and the potential whitening effect of its enzymatic peptides was explored. Taking tyrosinase inhibitory activity as the evaluation index, the enzyme hydrolysate process was optimized by response-surface methodology, and the optimal enzyme hydrolysate conditions were as follows: pH 5.82, 238 min enzyme hydrolysate time, and temperature of 54.5 °C. Under these conditions, the tyrosinase inhibition activity of Atrina pectinata mantle gelatin peptide (APGP) was 88.6% (IC50 of 3.268 ± 0.048 mg/mL). The peptides obtained from the identification were separated by ultrafiltration and LC-MS/MS, and then four new peptides were screened by molecular docking, among which the peptide Tyr-Tyr-Pro (YYP) had the strongest inhibitory effect on tyrosinase with an IC50 value of 1.764 ± 0.025 mM. The molecular-docking results indicated that hydrogen bonding is the main driving force for the interaction of the peptide YYP with tyrosinase. From the Lineweaver-Burk analysis, it could be concluded that YYP is inhibitory to tyrosinase and exhibits a mixed mechanism of inhibition. These results suggest that YYP could be widely used as a tyrosinase inhibitor in whitening foods and pharmaceuticals.

Recent advances in taste transduction mechanism, analysis methods and strategies employed to improve the taste of taste peptides.

Taste peptides are oligopeptides that enhance both aroma and taste of food, and they are classified into five categories based on their taste characteristics: salty, sour, umami, sweet, bitter, and kokumi peptide. Recently, taste peptides have attracted the attention of several fields of research in food science and commercial applications. However, research on taste receptors of taste peptides and their taste transduction mechanisms are not clearly understood and we present a comprehensive review about these topics here. This review covers the aspects of taste peptides perceived by their receptors in taste cells, the proposed transduction pathway, as well as structural features of taste peptides. Apart from traditional methods, molecular docking, peptidomic analysis, cell and animal models and taste bud biosensors can be used to explore the taste mechanism of taste peptides. Furthermore, synergistic effect, Maillard reaction, structural modifications and changing external environment are employed to improve the taste of taste peptides. Consequently, we discussed the current challenges and future trends in taste peptide research. Based on the summarized developments, taste peptides derived from food proteins potentially appear to be important taste substances. Their applications meet the principles of "safe, nutritious and sustainable" in food development.

Functional, physicochemical, and structural properties of the hydrolysates derived from the abalone (Haliotis discus subsp hannai Ino) foot muscle proteins.

This study was conducted to investigate functional, physicochemical, and structural properties of abalone foot muscle proteins (AFPs) and their hydrolysates (HAFPs) obtained using animal protease (HA), papain (HPP), and Protamex® (HP) at different time points. The HA-hydrolysate obtained after 0.5 h of treatment demonstrated the highest solubility at pH 7.0 (84.19%); the HPP-hydrolysate at 4 h exhibited the highest degree of hydrolysis (11.4%); the HPP-hydrolysate at 0.5 h had the highest oil holding capacity (2.62 g/g) and emulsion stability index (39.73 min), and the HP-hydrolysate at 4 h had the highest emulsifying activity index (93.23 m2/g) and foaming stability (91.45%); Regarding the physicochemical properties, the HPP-hydrolysates revealed the largest particle size, higher absolute zeta potential, and superior interfacial activity. Structural characterization demonstrated the enzymolysis-based changes in the composition and the secondary structure of the AFPs. These results provide practical support for the theoretical basis of the use of AFPs as a source of nutritive proteins in the food industry.

Effect of Drying Process on the Formation of the Characteristic Flavor of Oyster (Crassostrea hongkongensis).

Oysters are nutritious and tasty but difficult to store. Drying can extend the storage period of oysters and give them a unique flavor. In this study, the effects of four drying procedures, namely, vacuum freeze drying (VFD), vacuum drying (VD), natural sun-drying (NSD), and hot air drying (HAD), on the flavor characteristics of oysters (Crassostrea hongkongensis) were investigated using blanched oysters as a control (CK). Results showed that HAD produced more free amino acids than the other methods, but VFD retained the most flavor nucleotides. Compared with cold drying (VFD), hot drying (VD, NSD, and HAD) increased the abundance of organic acids, betaine, and aroma substances. Glutamic acid, alanine, AMP, hexanal, octanal, heptanal, (E, E)-2,4-heptadienal, (E)-2-decenal, nonanal, etc., are defined as the characteristic flavor compounds of dried oysters, with umami, sweet, green, fatty, and fruity aromas being the main organoleptic attributes of dried oysters. Glutamic acid, glycine, betaine, IMP, pentanal, ethyl heptanoate, (E, Z)-2,4-nonadienal, 1-octen-3-one, 2-hexenal, 2-octenal, hexanal, decanal were defined as markers to distinguish different drying methods. Overall, HAD showed improved flavor qualities and characteristics and was better suited for the highly commercialized production of dried oysters.

Effects of cold atmospheric plasma on endogenous enzyme activity and muscle protein oxidation in Trachinotus ovatus.

In this study, we investigated the effects of cold atmospheric plasma (CAP) technology on endogenous enzyme characteristics and muscle protein properties of the golden pomfret (Trachinotus ovatus) under different treatment power and time conditions. Results showed that the enzymatic activity of cathepsin B, L, and calpain in crude protease extracts (CPE) decreased significantly as the treatment power and treatment time of CAP increased (p < 0.05). Oxidative degradation of the CPE after exposure to CAP resulted in significant changes in the structure, total sulfhydryl, and carbonyl content of the CPE (p < 0.05). CAP of an appropriate intensity resulted in significant improvements in the color parameters, hydration properties, and textural property parameters of muscle proteins (p < 0.05). These results suggest that CAP, as a non-thermophysical modification technique, can inhibit the activity of endogenous enzymes as well as alter the protein function in food.

Effect of ultrasonic power on the stability of low-molecular-weight oyster peptides functional-nutrition W1/O/W2 double emulsion.

Ultrasonic-assisted treatment is an eco-friendly and cost-effective emulsification method, and the acoustic cavitation effect produced by ultrasonic equipment is conducive to the formation of stable emulsion. However, its effect on the underlying stability of low-molecular-weight oyster peptides (LOPs) functional-nutrition W1/O/W2 double emulsion has not been reported. The effects of different ultrasonic power (50, 75, 100, 125, and 150 W) on the stability of double emulsions and the ability to mask the fishy odor of LOPs were investigated. Low ultrasonic power (50 W and 75 W) treatment failed to form a well-stabilized double emulsion, and excessive ultrasound treatment (150 W) destroyed its structure. At an ultrasonic power of 125 W, smaller particle-sized double emulsion was formed with more uniform distribution, more whiteness, and a lower viscosity coefficient. Meanwhile, the cavitation effect generated by 125 W ultrasonic power improved storage, and oxidative stabilities, emulsifying properties of double emulsion by reducing the droplet size and improved sensorial acceptability by masking the undesirable flavor of LOPs. The structure of the double emulsion was further confirmed by optical microscopy and confocal laser scanning microscopy. The ultrasonic-assisted treatment is of potential value for the industrial application of double emulsion in functional-nutrition foods.

The current research status and strategies employed to modify food-derived bioactive peptides.

The ability of bioactive peptides to exert biological functions has mainly contributed to their exploitation. The exploitation and utilization of these peptides have grown tremendously over the past two decades. Food-derived peptides from sources such as plant, animal, and marine proteins and their byproducts constitute a more significant portion of the naturally-occurring peptides that have been documented. Due to their high specificity and biocompatibility, these peptides serve as a suitable alternative to pharmacological drugs for treating non-communicable diseases (such as cardiovascular diseases, obesity, and cancer). They are helpful as food preservatives, ingredients in functional foods, and dietary supplements in the food sector. Despite their unique features, the application of these peptides in the clinical and food sector is to some extent hindered by their inherent drawbacks such as toxicity, bitterness, instability, and susceptibility to enzymatic degradation in the gastrointestinal tract. Several strategies have been employed to eliminate or reduce the disadvantages of peptides, thus enhancing the peptide bioactivity and broadening the opportunities for their applications. This review article focuses on the current research status of various bioactive peptides and the strategies that have been implemented to overcome their disadvantages. It will also highlight future perspectives regarding the possible improvements to be made for the development of bioactive peptides with practical uses and their commercialization.

The Spatial Distribution Patterns, Physicochemical Properties, and Structural Characterization of Proteins in Oysters (Crassostrea hongkongensis).

Protein content, a vital component determining the nutritional quality of oysters, is unevenly distributed in different parts of oyster. In this study, the spatial distribution (visceral mass, mantle, gill, and adductor) patterns and structural characteristics of proteins, including water-soluble proteins (WSP), salt-soluble proteins (SSP), acid-soluble proteins (ASP) and alkali-soluble proteins (ALSP) of oysters (Crassostrea hongkongensis) were investigated with the amino acid analyzer, circular dichroism spectroscopy (CD), fourier transform infrared spectroscopy (FTIR), and fluorescence spectroscopy. The results showed that oyster proteins were mainly distributed in the visceral mass and mantle. The protein composition was WSP, SSP, ALSP, and ASP in descending order, which conformed to the ideal amino acid pattern. Variations in secondary structure, molecular weight distribution, and thermal denaturation temperatures of the oyster proteins were observed. SSP had wider bands (16-270 kDa) than those of ASP (30-37 kDa) and ALSP (66-270 kDa). Among the four proteins, the SSP of the mantle showed the highest thermal stability (87.4 °C), while ALSP of the adductor muscle had the lowest the lowest the peak denaturation temperature (Tm) (53.8 °C). The proportions of secondary structures in oyster proteins were different, with a higher proportion of solid protein ß-folds, and the exposure of aromatic amino acid residues and disulfide bonds and the microenvironment in which they were located were also different.

Novel insight into the role of processing stages in nutritional components changes and characteristic flavors formation of noble scallop Chlamys nobilis adductors.

Processing stages play critical role in the nutrition and flavor changes of marine products. This study investigated the nutrition and flavor profiles in noble scallop Chlamys nobilis adductor during boiling, rinsing, baking and drying processing stages by high performance liquid chromatography, headspace solid-phase microextraction and gas chromatography-tandem mass spectrometry. The results showed that the overall processing stages favorably preserved the essential amino acids. Drying obviously increased the umami and sweet amino acids contents by 72.08%, 67.77%, respectively (P < 0.05), and promoted the production of flavor nucleotides. In addition, the overall processing stages significantly increased the protein and lipid oxidation degree by (1.49-3.01)-fold and (4.25-5.81)-fold, respectively, compared with raw group (P < 0.05). Moreover, alcohols were the major volatiles in raw group, while the aldehydes, alcohols, and hydrocarbons predominated in rinsing, baking and drying stages. In conclusion, the processing maintained the nutrition value and improved the flavor of scallop adductors.

Abnormal Brain Activation During Verbal Memory Encoding in Postacute Anti-N-Methyl-d-Aspartate Receptor Encephalitis.

Background: Patients with postacute anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis are often left with permanent memory impairments. Given that NMDA receptors are essential to memory encoding, and encoding processes have been suggested to contribute to the success of memory retrieval, we investigate whether postacute anti-NMDA receptor encephalitis leads to abnormal brain activation during verbal memory encoding and its potential effects on subsequent memory retrieval performance. Methods: To address this issue, this study recruited 21 adult patients with anti-NMDA receptor encephalitis past the acute stage and 22 healthy controls (HCs). Functional magnetic resonance imaging (fMRI) data were collected when they completed an episodic memory task. Results: At the neural level, the patients showed higher brain activation than the HCs in the bilateral hippocampus/parahippocampus (HG/PHG), right superior temporal gyrus (STG), and right thalamus during memory encoding. At the behavioral level, the patients showed worse memory retrieval performance than the HCs. Importantly, greater brain activation in the left HG/PHG during memory encoding was significantly associated with worse memory retrieval performance among the patients. Conclusion: Our findings indicate that postacute anti-NMDA receptor encephalitis is likely related to altered brain activation during memory encoding. Particularly, less memory retrieval performance often observed in patients with postacute anti-NMDA receptor encephalitis may result from abnormal activation in HG during encoding. These observations may enhance our understanding of NMDA receptor dysfunction in the human brain. Impact statement Patients with anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis are often left with permanent memory impairments. In this study, brain activation during verbal memory encoding and its potential effects on subsequent memory retrieval performance are addressed using 21 adult patients with postacute anti-NMDA receptor encephalitis and 22 healthy controls. Greater brain activation in the left hippocampus/parahippocampus during memory encoding was significantly associated with worse memory retrieval performance among the patients. These observations enhance our understanding of NMDA receptor dysfunction in the human brain.

Altered executive control network connectivity in anti-NMDA receptor encephalitis.

OBJECTIVE: The goal of this study was to examine whether the static functional connectivity (FC) of the executive control network (ECN) and the temporal properties of dynamic FC states in the ECN can characterize the underlying nature of anti-N-methyl-d-aspartate (anti-NMDA) receptor encephalitis and their correlations with cognitive functions. METHODS: In total, 21 patients with anti-NMDA receptor encephalitis past the acute stage and 23 healthy controls (HCs) underwent a set of neuropsychological tests and participated in a resting-state fMRI study to analyse the static FC of the ECN and the temporal properties of dynamic FC states in the ECN. In addition, correlation analyses were performed to determine the correlations between the FC metrics and cognitive performance. RESULTS: Patients with anti-NMDA receptor encephalitis past the acute stage showed significant cognitive impairments compared to HCs. In accord with the results of neuropsychological tests, static intrinsic FC alterations and changed dynamic FC metrics of ECN were observed in the patients. Importantly, we observed significant correlations between altered ECN metrics and working memory, information processing speed, executive function performance in the patients. INTERPRETATION: Our findings suggest that cognitive impairments in patients with anti-NMDA receptor encephalitis past the acute stage are likely related to altered static and dynamic ECN connectivity. These observations may enhance our understanding of the pathophysiological mechanisms underlying cognitive function in this population.

Chrysophyllum cainito. L alleviates diabetic and complications by playing antioxidant, antiglycation, hypoglycemic roles and the chemical profile analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Chrysophyllum cainito L. (C. cainito) is a traditional folk medicine in tropical area which can be an alternative agent for diabetes mellitus. Although the antioxidant and antidiabetic activity of the extracts are reported, little is known on the antiglycation activity and effects on diabetic complications. AIM OF THE STUDY: This work was aimed to investigate the chemical profile, antidiabetic, antioxidant activities of C. cainito. Especially, the antiglycation potential as well as the relationships between components and activities were evaluated. MATERIALS AND METHODS: The content of the primary components (polyphenols, flavonoids, steroids, and triterpenes), antioxidant, and hypoglycemic effects of ethanolic extracts from C. cainito leaves (CCE-1, 2, 3, 4) and stems (CSE-1, 2, 3, 4) were analyzed and detected. The chemical profiles of CCE-2 were characterized by HPLC-Q-TOF-MS/MS. The antiglycation and protection against oxidative stress effects were determined by in vitro assays. Relationship between bioactivities and components was analyzed by principal component analysis (PCA), heatmap analysis, and Pearson correlation analysis. RESULTS: The composition was diverse between leaves and stem extracts with different activities. CCE-2 possessed the highest DPPH scavenging activity. CSE-2 displayed the highest ABTS scavenging activity and ferric reducing power. While CCE-3 showed the most effective inhibition on α-amylase and α-glucosidase activity (IC50 4.103 ± 0.332 µg/mL and 0.180 ± 0.006 mg/mL, respectively). PCA analysis showed that the most important variables in PC1 (60.7%) were total polyphenol and antioxidant activities. The hypoglycemic activity and contents of steroids showed important correlation. Advanced glycation end products formation was effectively inhibited by CCE-2 with myricetin 3-O-rhamnoside as the main constituent. CCE-3 displayed the highest protection effect against L02 cell line oxidation damage. CONCLUSIONS: C. cainito leaves might be a promising candidate for antioxidant, hypoglycemic and antiglycation dietary supplement or potential agent against diabetes associated chronic diseases.

The long-term outcome of neuropsychological function is favorable in patients with non-malignancy related anti-GABABR encephalitis: a case series.

BACKGROUND: Anti-GABABR encephalitis is a rare type of autoimmune encephalitis, which often presents with memory impairments, behavioral changes and seizures. This case series describes the neuropsychological function recovery pattern in five adult patients with anti-GABABR encephalitis. CASE PRESENTATION: We recruited five patients with clinically confirmed anti-GABABR encephalitis without any accompanying malignancy. Comprehensive neuropsychological evaluation was conducted on each patient. All the five patients were evaluated in the chronic phase. Five age and gender matched healthy adults were recruited as control group. Our study demonstrated that the neuropsychological function of the patients with anti-GABABR encephalitis was no different with respect to the control group during the chronic phase (more than 6 months after onset). Moreover, one patients with neuropsychological evaluation at acute (within 2 months after onset of symptoms), post-acute (2 to 6 months after onset) and chronic phases respectively, presented neuropsychological function recovered as early as in the post-acute phase and only showed cognition impairment in the acute phase. CONCLUSIONS: The results of this retrospective study indicate a favorable long-term neuropsychological function outcome in adult patients with anti-GABABR encephalitis, despite severe memory deficits occurring during the acute phase. These findings improve our understanding related to the prognosis of neuropsychological function in anti-GABABR encephalitis.

A multifunctional CeO2@SiO2-PEG nanoparticle carrier for delivery of food derived proanthocyanidin and curcumin as effective antioxidant, neuroprotective and anticancer agent.

The nanoparticle systems could effectively overcome the drug delivery challenges of food bioactive compounds. In this study, a novel and effective multifunctional PEG modified CeO2@SiO2 nanoparticle (CSP-NPs) system was successfully fabricated. Food derived proanthocyanidin (PAC) and curcumin (Cur) were loaded onto CSP-NPs and formed as PAC-NPs and Cur-NPs. Fourier transform Infrared spectra, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and dynamic light scattering were used to characterize the prepared NPs. CSP-NPs, PAC-NPs and Cur-NPs displayed spherical shape with about 35-45 nm size. The bioactivity analysis revealed that CSP-NPs system could effectively deliver PAC and Cur to exhibit strong antioxidant activity, potent neuroprotective effect against Aß1-42-mediated toxicity in PC-12 cells (recovered cell viability from 57.5% to 81.0% at the dose of 25 µg/mL) and effective antiproliferative effects on HepG2 and Hela cells. Besides, all prepared nanoparticles (0-100 µg/ml) used in this study showed no significant toxicity on cell models of antioxidative and neuroprotective activities, excepting for cancer cells, suggesting that these nanoparticles had the potential of being utilized in drug delivery. Therefore, CSP-NPs might be a promising delivery system for hydrophilic molecule proanthocyanidin and hydrophobic molecule curcumin against the oxidative damage, neurodegenerative diseases and cancer, which could facilitate the application of food derived nutrients in functional foods industry.

Ultrafiltration isolation, physicochemical characterization, and antidiabetic activities analysis of polysaccharides from green tea, oolong tea, and black tea.

Both fermentation degree and preparation method of polysaccharides could influence the bioactivity of tea polysaccharides. The aim of this study was to compare the physicochemical characterization and biological activities of the polysaccharides isolated by ultrafiltration method from three kinds of tea (green tea, oolong tea, and black tea). The bioactivities of tea polysaccharide fractions were compared from four aspects, including antioxidant activities, antiglycation activities, α-glucosidase inhibitory capability, and hypoglycemic effects on L6 myotubes. Results showed that six polysaccharides (GTPS1, GTPS2, OTPS1, OTPS2, BTPS1, and BTPS2) had different contents of neutral sugar and uronic acid, and they showed different morphologies. Six polysaccharides were composed of the seven monosaccharides with different molar ratios. BTPS1 exhibited the highest DPPH scavenging activity and hydroxyl radical scavenging activity (P < 0.05), and BTPS1 also showed the strongest antiglycation inhibitory effects (P < 0.05). BTPS1 and BTPS2 showed strong inhibitory capacity on α-glucosidase and hypoglycemic effects in L6 skeletal muscle cells. The result suggested that the degree of fermentation of tea could improve their bioactivities (BTPS > OTPS >GTPS), and TPS1 with smaller molecular weight distribution showed higher bioactivities than TPS2. This study can provide a scientific foundation for the application of tea polysaccharides and related functional products.