The superabsorbent hydrogels were synthesized by grafting acrylic acid and acrylamide onto pineapple peel carboxymethyl cellulose and effect of carclazyte introduction was compared. The structure and morphology of the superabsorbents were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, and field emission scanning electron microscopy. Swelling behaviors of the superabsorbents were investigated in distilled water, 0.9% NaCl solution, various salt and pH solutions, as well as surfactant solutions and simulated physiological fluids. The swelling dynamic mechanism of the superabsorbents was explained well by Fickian diffusion and Schott’s pseudo-second-order models. The introduction of carclazyte effectively improved the swelling capacity of the superabsorbents in various solutions as well as its salt- and pH-sensitivity. The prepared superabsorbents also exhibited excellent sensitivities to various surfactant solutions and simulated physiological fluids, showing potential applications in the biomaterials field.Keywords: carclazyte; characterization; pineapple peel carboxymethyl cellulose; superabsorbent; swelling;

Novel composite hydrogels were synthesized by grafting of acrylic acid onto pineapple peel cellulose and addition of kaolin or sepia ink in ionic liquid 1-butyl-3-methylimidazolium chloride, using potassium persulfate as a free radical initiator and N,N′-methylenebisacrylamide as a crosslinking agent. The structure and morphology of the prepared hydrogels were characterized by Fourier transform infrared spectroscopy, field emission scanning electron microscope, X-ray diffraction, thermogravimetry and differential scanning calorimetry. Kaolin and sepia ink improved the thermal stability of the hydrogels. Swelling studies on the prepared hydrogels indicated sepia ink and kaolin affected the swelling ratio and pH-responsive properties. The optimum swelling pH value for the hydrogels was shifted from 7.0 to 12.0 in the presence of sepia ink. The effects of kaolin and sepia ink contents on methylene blue adsorption capacity of the prepared hydrogels were also investigated. The optimum methylene blue adsorption capacity reached 153.85 mg/g at 10% of kaolin and 142.21 mg/g at 20% of sepia ink. The pseudo-second-order kinetic model fit well with the experimental results, indicating the adsorption was chemisorption behavior.

In order to study the molecular mechanisms of green tea polyphenols (GTPs) in treatment or prevention of breast cancer, the cytotoxic effects of GTPs on five human cell lines (MCF-7, A549, Hela, PC3, and HepG2 cells) were determined and the antitumor mechanisms of GTPs in MCF-7 cells were analyzed. The results showed that GTPs exhibited a broad spectrum of inhibition against the detected cancer cell lines, particularly the MCF-7 cells. Studies on the mechanisms revealed that the main modes of cell death induced by GTPs were cell cycle arrest and mitochondrialmediated apoptosis. Flow cytometric analysis showed that GTPs mediated cell cycle arrest at both G1/M and G2/M transitions. GTP dose dependently led to apoptosis of MCF-7 cells via the mitochondrial pathways, as evidenced by induction of chromatin condensation, reduction of mitochondrial membrane potential (ΔΨm), improvement in the generation of reactive oxygen species (ROS), induction of DNA fragmentation, and activations of caspase-3 and caspase-9 in the present paper.评估茶多酚对人乳腺癌细胞MCF-7 凋亡的影响, 并探讨了其作用机制。全面考察了茶多酚对抗乳腺癌的分子机制,为茶 多酚作为抗肿瘤辅助药物提供理论依据。首先选取不同组织来源的五种人肿瘤细胞(人肝 癌细胞HepG2、人肺癌细胞A549、人前列腺癌 细胞PC3、人宫颈癌细胞Hela、人乳腺癌细胞 MCF-7)作为体外模型,以MTT 法检测茶多酚 对其增殖抑制作用。然后,选用最敏感细胞 MCF-7 为研究对象,采用流式细胞术检测茶多酚 对细胞周期分布的影响,用Hoechst 3328 染色法 观察茶多酚对细胞核形态的影响,用JC-1 染色法 观察茶多酚对细胞线粒体跨膜电位的影响,用双 氯荧光素(DCFH-DA)染色法观察茶多酚对细 胞活性氧(ROS)水平的影响,用凝胶电泳DNA 片段测定法(DNA ladder)观察茶多酚处理后细 胞DNA 断裂情况,用蛋白质印迹法(Western blot)检测茶多酚对细胞凋亡关键蛋白caspase-3 和caspase-9 表达的影响,全面探讨了茶多酚体外 抗肿瘤机制。实验结果显示,茶多酚能够通过诱导细胞周期阻 滞和线粒体凋亡抑制MCF-7 细胞增殖。茶多酚诱 导线粒体凋亡的途径是使线粒体跨膜电位下降, 促使MCF-7 细胞内ROS 生成,促使细胞DNA 断裂和促进细胞内caspase-3 和caspase-9 的活化。

•Innovative hydrogels based on pineapple peel cellulose/PVA/SBA-15 were prepared.•Papain was immobilized onto the hydrogels by absorption/crosslinking.•The immobilized papain was increased in pH, thermal and storage stability.Hydrogel composites based on pineapple peel carboxymethyl cellulose, polyvinyl alcohol and mesoporous silica SBA-15 were synthesized by an eco-friendly method of repeated freeze-thaw cycles for the application of papain immobilization. The experiment was optimized to obtain an efficient papain immobilization carrier. Simultaneously the immobilization conditions, including enzyme concentration, pH, crosslinker concentration and cross-linking time were optimized. The immobilized papain had maximum activity at low reaction temperature of 40 °C and showed pH-sensitivity by exhibiting a rapid decrease of activity within a narrow range from pH 7.0 to pH 7.5. Compared with the free papain, the immobilized papain revealed enhanced pH, thermal and storage stability. After 2 h incubation at 80 °C, the immobilized papain retained 56% of its initial activity while the free papain only retained 16%. After 10 days of storage, 79% of the initial activity was retained for the immobilized papain while only 27% for the free papain.

•Immunostimulating polysaccharide (HEP-W) was purified from Hericium erinaceus.•Structure of HEP-W was characterized by HPGPC, GC, FT-IR and NMR.•HEP-W promoted macrophage phagocytosis and increased the secretion of NO and cytokines.•The pattern recognition receptors of HEP-W were elucidated for the first time.•HEP-W exhibited potent immunomodulating activity through MyD88/IRAK-1/TRAF-6/PI3K/AKT/MAPKs signaling pathways.A novel heteropolysaccharide fraction (HEP-W) with great immunomodulatory activity was isolated from the fruiting bodies of Hericium erinaceus. Structural characterization revealed that HEP-W had an average molecular weight of 1.59 × 104 Da and was composed of rhamnose, fucose, mannose, glucose and galactose at a molar ratio of 0.98:1.59:0.89:5.60:7.06. The main glycosidic linkage types of HEP-W consisted of (1→)-α-D-Glc, (1→3,6)-α-D-Glc, (1→2,6)-α-D-Gal, T-β-Gal, (1→3,4)-β-D-Man, (1→3)-α-Rha, and (1→2)-β-L-Fuc by periodate oxidation-Smith degradation and NMR analysis. The bioactivity tests showed that HEP-W could significantly promote the pinocytic and phagocytic capacity and increase the NO, IL-6 and TNF-α secretion by activating corresponding mRNA expression in macrophages through MyD88/IRAK-1/TRAF-6/PI3K/AKT/MAPKs signaling pathways. Meanwhile, toll-like receptor 2 and mannose receptor were found to act as synergistic PRRs to co-regulate the immunomodulatory response to HEP-W in macrophages. These findings provide a molecular basis for the application of HEP-W as a natural immunoregulatory agent in functional foods.Hericium erinaceus polysaccharide (HEP-W) can significantly stimulate the immunomodulatory activity on murine macrophages.Download high-res image (194KB)Download full-size image

•Composite hydrogels was prepared with tea cellulose and graphene oxide.•The prepared hydrogel was better at TPA parameters and thermostability.•The prepared hydrogel had good adsorption capacity and adsorption ratio.•The prepared hydrogel showed conformability with pseudo second-order model.Hydrogels based on tea residue cellulose and graphene oxide were prepared by a homogeneous mixture of tea cellulose and graphene oxide in ionic liquid 1-allyl-3-methylimidazolium chloride. The prepared composite hydrogels of graphene oxide/tea cellulose were characterized by X-ray diffraction, Fourier transform infrared, thermogravimetry analysis and texture profile analysis. The effect of graphene on methylene blue adsorption capacity of the prepared hydrogels was also investigated. After the addition of graphene oxide, the hydrogels showed higher thermal stability and enhanced textural property. The weight loss peak was shifted from 280 °C to 320 °C, and the values of hardness, fracturability and gumminess were 12.7, 4.1 and 17.8 times respectively of the undoped tea cellulose hydrogel. As an absorbent, the graphene oxide/tea cellulose hydrogels had certain adsorption capacity (46.35 mg/g) and adsorption ratio (92.7%) for methylene blue and conformed with pseudo-second-order kinetic model.Download high-res image (92KB)Download full-size image

A new and efficient technique is described for the production of diacylglycerols (DAGs) by the esterification of oleic acid with glycerol catalyzed by diatomite-loaded SO42−/TiO2. DAGs show some potential health benefits compared to triacylglycerols, and also can be used to produce the novel industrial plasticizer epoxy fatty acid methyl ester in material science. Diatomite-loaded SO42−/TiO2 catalyst was prepared and characterized, and the selected conditions for the synthesis of DAGs were determined to be: reaction time = 6.0 h, temperature = 210 °C, catalyst loading = 0.1% of the oleic acid weight, and mass ratio of oleic acid to glycerol = 2:1. Under these conditions, DAGs yield reached 59.6% with a purity of 69.6% after a one-stage molecular distillation. Diatomite-loaded SO42−/TiO2 as a solid catalyst could be recycled and reused with high catalytic efficiency. Under the same conditions, diatomite-loaded SO42−/TiO2 showed a better catalytic performance than the commercial solid acid SO42−/ZrO2-Al2O3. Based on this, a two-step reaction method for the production of DAGs was performed and provided a yield similar to the one-step method (58.3% vs. 59.6%), but with a shorter reaction time (4 h vs. 6 h). It is concluded that a two-step reaction method could be a better alternative to the one-step production of DAGs in the presence of diatomite-loaded SO42−/TiO2.Download high-res image (219KB)Download full-size image

•Compatibility tests above 25 °C showed that SheaOL25 could serve as blending base oil for preparing specialty fats.•Blending SheaOL25 and palm stearin had positive impacts on the crystallization behavior of the system utilized.•Stability of O/W emulsion system with SheaOL25 as oil phase was significantly improved.•Findings will contribute to expand the application of shea olein in production of specialty fats.To expand low melting point “liquid” base oil categories of plastic fats, the soft fat named SheaOL25 as a byproduct of shea butter with a melting point of 25.5 °C was achieved via solvent fractionating of shea butter, and abounded in oleic acid and stearic acid/oleic acid/oleic acid (SOO) type triacylglycerols. The compatibility test with palm-based oil and coconut oil showed the desirable linear relationship of isothermal curve. At temperatures above 25 °C, SheaOL25 exhibits good compatibility and could serve as a blending base oil for preparing specialty fats. Compared with palm olein, blending SheaOL25 and palm stearin can significantly expedite crystallization rate and retard crystallization rate after interesterification, thereby stabilizing the β′ crystal form in the system. Further exploration of SheaOL25 as “liquid” oil in oil-in-water emulsion system revealed that SheaOL25 as the oil phase can significantly improve the system's stability compared with the control groups of soybean oil and palm olein towards maintaining the particle size and emulsion stability under high temperatures.

MDs [monoacylglycerols (MAGs) and diacylglycerols (DAGs) mixture] are widely-used emulsifiers in specialty fats industrial production. An enzymatic production of highly unsaturated MDs (HUSMDs) and its effects on the storage stability of a palm oil-based shortening system are reported. Oleic acid and corn oil were used to produce HUSMDs in a bubble column reactor (BCR) system in the presence of Novozyme 435. Under the optimized reaction conditions, the content of HUSMDs in the products was above 82 wt% with 46.67 wt% of MAGs and 35.56 wt% DAGs, respectively. Moreover, in the subsequent evaluation of MDs’ effects on the storage stabilities of a palm oil-based shortening system (IEPO), HUSMDs proved to be a potent emulsifier with decent aeration properties and a possible alternative to saturated MAGs and DAGs (SMDs) made from fully hydrogenated high erucic acid colza oil. Compared with SMDs, HUSMDs decreased the crystallization rate significantly. The microstructure of them shows improved stability of β′ crystals, and no obvious aggregation of crystals was recorded in IEPO with HUSMDs, which also demonstrated the most stable hardness.

•Natural cellulose and sepia ink was isolated from pineapple peel and Sepia pharaonis, respectively.•Novel modified pineapple peel cellulose hydrogels embedded with sepia ink were synthesized.•Characterization of the hydrogel was investigated by FTIR, FESEM, XRD, DSC and TG.•Adsorption kinetics of the hydrogels prepared in different process conditions on methylene blue were investigated.•Sepia ink can improve thermal stability and methylene blue adsorption ability of hydrogels.Novel composite hydrogels based on pineapple peel cellulose and sepia ink were synthesized by homogeneous acetylation of cellulose in ionic liquid 1-butyl-3-methylimidazolium chloride. The structure and morphology of the prepared hydrogels were characterized by Fourier transform infrared spectroscopy, field emission scanning electron microscope, X-ray diffraction, thermogravimetry and differential scanning calorimetry. The effects of acetylation time, acetylation temperature, molar ratio of acetic anhydride/anhydroglucose unit and the additive amount of sepia ink on methylene blue adsorption capacity of the hydrogels embedded with sepia ink were also investigated. Methylene blue adsorption of the hydrogels followed pseudo-second-order kinetic model and sepia ink improved adsorption capacity significantly. The adsorption capacity at equilibrium was increased from 53.72 to 138.25 mg/g when the additive amount of sepia ink of the hydrogels was 10%.

•Cellulose was extracted from tea residue and prepared into composite hydrogels with four additives.•Addition of chitosan and guar gum improved at TPA parameters and thermostability.•Addition of κ-carrageenan and soluble starch improved hydrogels at equilibrium swelling ratio and NaSA loading ratios.•Tea cellulose composite hydrogels showed non-cytotoxicity and cell compatibility.Composite hydrogels were prepared from tea cellulose in ionic liquid of 1-allyl-3-methylimidazolium chloride and effect of κ-carrageenan, chitosan, guar gum and soluble starch on characteristics of the prepared hydrogels were investigated. The prepared hydrogels were characterized via Fourier transform infrared, thermogravimetry analysis, differential scanning calorimetry. Sodium salicylate was used as the model drug to compare the swelling, drug loading and releasing kinetics of the prepared hydrogels. Thiazolyl blue tetrazolium bromide assay and relative growth rates were adopted to evaluate cell cytotoxicity and biocompatibility of the prepared hydrogels. Chitosan and guar gum could improve thermostability and mechanical characteristics of the composite hydrogels, while κ-carrageenan or soluble starch could improve equilibrium swelling ratio, sodium salicylate loading and releasing. Guar gum and chitosan could increase permeation resistance and were beneficial for release control of the hydrogels. Addition of chitosan, κ-carrageenan, guar gum and soluble starch were proven cell compatibility and non-cytotoxicity.

In this research, 2,2′-azobis (2-amidinopropane)-induced oxidative stress in human erythrocytes and 50 % fetal bovine serum-induced steatosis in human liver L02 cell were used to evaluate the functions of epicatechin gallate (ECG) in regulation of lipid metabolism and inhibition of oxidative stress. The results indicated that the antioxidant rationales of ECG in biological systems mainly involved in suppressing the generation of reactive oxygen species by preserving the antioxidant enzyme activities of (superoxide dismutase and glutathione peroxidase) and reducing the consumption of reduced glutathione as well as inhibiting the production of thiobarbituric acid-reactive substances. The anti-nonalcoholic fatty liver disease rationales of ECG included inhibiting the growth of steatosis L02 cells, reducing the accumulation of hepatic lipid through lowering the levels of total cholesterol and triacylglycerol, and suppressing the leakage volume of enzymes (aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase).

To investigate the influence of in vitro gastrointestinal digestion on contents of bioactive compounds and antioxidant activities of heat-treated soymilks, changes of total phenolics content (TPC), total flavonoids content (TFC), content and profile of isoflavones, oxygen radical absorbance capacity (ORAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric-reducing antioxidant power (FRAP) were assayed after different heat treatments (at 95 °C for 20, 40, 60 min; 121 °C for 3, 6, 9 min and 143 °C for 20, 40, 60 s respectively) and gastrointestinal digestion. Results showed that digestion significantly influenced the contents of bioactive compounds and antioxidant activities of soymilks. Increases of DPPH radical scavenging activity, FRAP and ORAC of the heat-treated soymilks after gastric digestion were consistent with the increases of TPC (110.68–152.60 %) and TFC (4.48–31.10 %). In the dialysate fractions as the absorbable and utilized part, it was found that TPC, TFC, isoflavones and antioxidant activities (DPPH radical scavenging activity, FRAP and ORAC) were significantly decreased as compared with the gastric digestion fractions and duodenal fractions. Analysis showed that the bioaccessibility of TPC reached 107.17–125.14 %, TFC reached 34.63–67.19 % and total isoflavones reached 34.40–41.22 %, respectively, indicating the rich bioaccessible compounds in soymilk. Daidzein and its derivates were proven as the most bioaccessible isoflavones (about 36.99–44.14 %). Glucoside isoflavones showed the highest bioaccessibilities followed by malonylglucosides, acetylglucosides and aglycones. Overall, the soymilks treated at 95 °C and 60 min and 121 °C and 9 min had higher bioactive compounds contents, antioxidant activities and bioaccessibilities in the dialysate fractions.

Hydrogels and polyvinyl pyrrolidone (PVPP) composite hydrogels were prepared from pineapple peel cellulose with 1-allyl-3-methylimidazolium chloride via different heating and cooling processes. The prepared hydrogels were characterized via the methods of texture profile analysis, Fourier infrared transform, X-ray diffraction, thermogravimetry analysis, differential scanning calorimetry and field emission scanning electron microscope. Swelling kinetics of the prepared hydrogels and their release kinetics were also compared in vitro with sodium salicylate (NaSA) as model drug. The results showed the hydrogels and PVPP-doped composite hydrogels exhibited differences in characterizations and NaSA release. PVPP increased the mechanical properties and thermal stability of the composite hydrogels. The freeze-dried hydrogels exhibited higher equilibrium swelling ratio and NaSA load ratio than the oven-dried hydrogels. PVPP addition decreased the equilibrium swelling ratio and NaSA load ratio of the freeze-dried hydrogels but increased those of the oven-dried hydrogels. Oven-drying processing and PVPP were propitious for slowing NaSA release.

To reveal the relationships between the activity of trypsin and its structural change, changes of trypsin in biological activity induced by complex with Bowman-Birk trypsin inhibitor (BBTI), Kunitz soybean trypsin inhibitor (KSTI, type I-S) and tea polyphenol (TP) were detected and their relationship with the secondary structure changes were studied by far-UV circular dichroism (CD) spectra measurement. BBTI and KSTI were also irradiated by ultrasonic to compare the effects on trypsin. The rank was found as KSTI > BBTI > TP according to their inhibitory activities against trypsin. Yet BBTI exhibited much stronger resistance against ultrasonic irradiation than KSTI. BBTI, KSTI and TP were found inactivate trypsin by modifying the secondary structures and far-UV spectrum of trypsin. Complex of trypsin with ultrasonic-treated BBTI and native BBTI and KSTI exhibited the similar modified effects in secondary structures, decrease of α-helix and β-turn content, increase of β-sheet content and unchanged random coil content basically. But complex of trypsin with ultrasonic-treated KSTI exhibited less modified effects because of inactivation by ultrasonic irradiation. The changes of trypsin in secondary structure induced by complex with TP showed different from those induced by complex with BBTI and KSTI, increase of α-helix content, decrease of random coil content and unchanged β-sheet and β-turn content basically.

•Carboxymethyl cellulose was prepared from bamboo shoots via chemical modification.•Modified bamboo shoot cellulose and β-cyclodextrin were cross linked to hydrogel.•The hydrogel showed perfect swelling ratio at low temperature and high pH value.•The prepared hydrogel was sensitive to changes of temperature, pH value and salt.•Drug release ratio of hydrgel differed in simulated intestinal and gastric liquid.Carboxymethyl cellulose was derived from bamboo shoot cellulose via chemical modification and was prepared into composite hydrogels by cross-linkage with β-cyclodextrin using epichlorohydrin as crossing agent. The structure of the prepared hydrogel was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The results showed that the prepared composite hydrogel was sensitive to surrounding changes in pH value, temperature and ionic strength. Under the surroundings of low temperatures and high pH values, the prepared hydrogel had significant high swelling ratios (23338 ± 988% at 15 °C and 6937 ± 112% at pH 8.0, respectively). In the solution of 0.1 mol/L NaCl, the hydrogel showed the maximum water retention rate (48.73%). Sodium salicylate was used as the model drug to study the behaviors of hydrogel adsorption and release in simulated intestinal (at pH 7.4) and gastric liquid (at pH 1.8) surroundings. The prepared composite hydrogel exhibited higher drug release ratio in simulated intestinal liquid (63.09% after 380 min) than in gastric liquid (22.09% after 400 min). These pH responses of the prepared composite hydrogel showed its potential applications, especially as the drug carrier to attain control release of drugs under different surrounding conditions or organs in human body.

•Cellulose extracted from tea was prepared as hydrogels and for immobilizing papain.•Tea cellulose hydrogels were coated with magnetic Fe3O4.•Magnetic-cellulose-hydrogel-embedded papain showed magnetic field sensitive.•The optimal pH of the embedded papain was shifted to 8.0.•The optimal temperature of the embedded papain was shifted to 90 °C.Papain was embedded and immobilized in hydrogels prepared from tea cellulose by dissolving in ionic liquid of 1-allyl-3-methylimidazolium chloride and coating with magnetic Fe3O4 via reaction of FeCl3/FeCl2 solution with ammonium hydroxide. The prepared magnetic-cellulose-hydrogel-embedded papain was characterized via vibrating sample magnetometer, scanning electron microscope, X-ray diffraction, Fourier transform infrared, thermogravimetry analysis and differential scanning calorimetry. Thermal stability, optimal pH, optimal temperature, Michaelis constant and maximum reaction rate were compared between free papain and magnetic-cellulose-hydrogel-embedded papain. The magnetic-cellulose-hydrogel-embedded papain was sensitive to magnetic field and showed paramagnetic behavior, higher thermal stability and lowed substrate affinity. The optimal pH and optimal temperature of the magnetic-cellulose-hydrogel-embedded papain were shifted to 8.0 and 90 °C respectively.Graphical abstracts