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To develop a biological bone tissue scaffold with uniform pore size and good cell adhesion was both challenging and imperative. We prepared modified cellulose nanocrystals (CNCs) dispersants (K-PCNCs) by ultrasound-assisted alkylation modification. Subsequently, nano-hydroxyapatite (HC-K) was synthesized using K-PCNCs as a dispersant and composited with polyvinyl alcohol (PVA) to prepare the scaffold using the ice template method. The results showed that the water contact angle and degree of substitution (135°, 1.53) of the K-PCNCs were highest when the ultrasound power was 450 W and the time was 2 h. The dispersion of K-PCNCs prepared under this condition was optimal. SEM showed that the pore distribution of the composite scaffolds was more homogeneous than the PVA scaffold. The porosity, equilibrium swelling rate, and mechanical properties of the composite scaffolds increased and then decreased with the increase of HC-K content, and reached the maximum values (56.1 %, 807.7 %, and 0.085 ± 0.004 MPa) at 9 % (w/w) of HC-K content. Cell experiments confirmed scaffold has good cytocompatibility and mineralization capacity. The ALP activity reached 1.71 ± 0.25 (ALP activity/mg protein). In conclusion, the scaffolds we developed have good biocompatibility and mechanical properties and have great potential in promoting bone defect repair.

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The main limitation associated with the oral delivery of ascorbyl palmitate, a potent food antioxidant, is its susceptibility to oxidative deterioration. The main objective of the current research was to encapsulate ascorbyl palmitate into corn starch matrix using extrusion cooking and evaluate its release behavior and oxidative stability. Results showed that ascorbyl palmitate was efficiently encapsulated (96.06-99.28%) in the starch matrix using the extrusion technique. The release behavior of ascorbyl palmitate from the extruded starch matrix during simulated upper gastrointestinal tract conditions was slow but steady (18.92-28.32% after 180 min) and presented a sustainable antioxidant activity. Acid treatment (pH 2.0) increased the release rate of ascorbyl palmitate from the extruded starch matrix. Furthermore, the antioxidant capacity of ascorbyl palmitate released from the extruded samples stored in both darkness and under UV radiation at 40 °C was found to be remarkably retained (p > 0.05) for up to three months.

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For the treatment of infected bleeding wounds, we compounded methacrylate anhydride dopamine (DAMA) and Zn-doped whitlockite nanoparticles (Zn-nWH) into methacrylate anhydride quaternized chitosan (QCSMA) to obtain a multifunctional hydrogel dressing (QCSMA/DAMA/Zn-nWH) with hemostasis, disinfection and wound healing promotion. QCSMA/DAMA/Zn-nWH exhibited good adhesion (0.031 MPa) and DPPH scavenging ability (94%), favorable biocompatibility (hemolysis ratio < 2%, no cytotoxicity), and showed a low BCI value (< 13%) in vitro coagulation test and could activate coagulation pathway. In addition, QCSMA/DAMA/Zn-nWH had excellent hemostatic effect (129 ± 22 s, 27 ± 5 mg) in vivo compared with the control (571 ± 15 s, 147 ± 31 mg) and CCS (354 ± 27 s, 110 ± 46 mg). Meanwhile, QCSMA/DAMA/Zn-nWH showed excellent antibacterial properties (> 90% against S. aureus and E. coli) and could promote collagen deposition, reduce inflammatory expression and promote wound healing. All results indicate that these multifunctional hydrogel dressings have great potential in clinical hemostasis and anti-infection healing.

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Eco-responsible flame retardant treatments with some resistance to washing are of considerable interest in the sale and applications of technical garments and home textiles. Thus, in the present study, a nano-hybrid composite based on kaolinite-TiO2 was prepared and incorporated into the fibers of cotton fabric through a more sustainable route compared to existing commercial processes. SEM analyses revealed a mineral covering of the treated cotton fibers, which do not propagate flames when exposed to fire and have a self-extinguishing behavior after the heat source removal. The method proved to be efficient in obtaining a cotton product with high fireproof performance. It was observed that after functionalization, the fabric showed a thermal degradation 41% less at 800 °C, an increase in the residue formation, and a reduction of about 85% in peak heat release measured by PCFC. Some resistance to washing was noticed, and the mechanical resistance of fibers was preserved.

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A fluorescent assay for the selective analysis of tartrazine was developed. Tartrazine is a health-threatening food additive commonly used as fake saffron. An optical nanosensor was fabricated based on molecular imprinting technique in which carbon dots (CDs) as fluorophores and tartrazine as a template molecule were embedded in molecularly imprinted polymer (MIP) matrix. The synthesized CDs embedded in MIP (CDs-MIP) was characterized by various methods. The fluorescence intensity of (CDs-MIP) was selectively quenched in the presence of tartrazine in comparison with other similar food color additives. The correlation between the quenching of CD-MIP and the concentration of tartrazine was used as an optical sensing for rapid detection of tartrazine in the range of 3.3-20.0 nM (1.8-10.7 µg L-1) with detection limit of 1.3 nM (0.70 µg L-1). Eventually, the designed nanosensor was successfully applied for tartrazine detection in foodstuffs such as fake saffron, saffron tea and saffron ice cream samples.

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The co-pigmentation reactions involving anthocyanins of sour cherry (Prunus cerasusL.) were investigated with tannic, caffeic, 4-hydroxybenzoic, gallic, and malic acids at pH 3.5. The influence of the co-pigments with different concentrations (120, 240, 480, and 960 mg/L), and temperatures (20, 40, 60, 80 and 100 ℃), on the co-pigmentation effects, stoichiometric ratio (n), the equilibrium constant (K) and thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were determined.The strongest immediate co-pigmentation reactions were observed at 960 mg/L, being significantly highest using tannic acid; also,the greatest bathochromic and hyperchromic effects were reasonable for itsn,K, and ΔG° values of 0.64, 56.55, and -10.00 kJ/mol, respectively. Furthermore, tannic and caffeic acids, with the highest negative values ofΔH°(-11.74 kJ/mol) andΔS°(-8.08 J/K.mol) led to the most excellent stability at 100 ℃.The presence of anthocyanins in the sour cherry extract was confirmed with the Fourier-transform infrared spectroscopy technique.

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This work presents a simple and low-cost analytical approach to detect adulterations in ground roasted coffee by using voltammetry and chemometrics. The voltammogram of a coffee extract (prepared as simulating a home-made coffee cup) obtained with a single working electrode is submitted to pattern recognition analysis preceded by variable selection to detect the addition of coffee husks and sticks (adulterated/unadulterated), or evaluate the shelf-life condition (expired/unexpired). Two pattern recognition methods were tested: linear discriminant analysis (LDA) with variable selection by successive projections algorithm (SPA), or genetic algorithm (GA); and partial least squares discriminant analysis (PLS-DA). Both LDA models presented satisfactory results. The voltammograms were also evaluated for the quantitative determination of the percentage of impurities in ground roasted coffees. PLS and multivariate linear regression (MLR) preceded by variable selection with SPA or GA were evaluated. An excellent predictive power (RMSEP = 0.05%) was obtained with MLR aided by GA.

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In this study, the aim was to determine the bioaccessibilities of carnosic acid in sage and rosemary and in vitro inhibitory effects of these samples on lipid and starch digestive enzymes by evaluating the lipase, α-amylase and α-glucosidase enzyme inhibition activities. The content of carnosic acid in rosemary (18.72 ±â€¯0.33 mg/g) was found to be higher than that content of that in sage (3.76 ±â€¯0.13 mg/g) (p < 0.05). The carnosic acid bioaccessibilities were found as 45.10 ±â€¯1.88% and 38.32 ±â€¯0.21% in sage and rosemary, respectively. The tested sage and rosemary showed inhibitory activity against α-glucosidase (Concentration of inhibitor required to produce a 50% inhibition of the initial rate of reaction - IC50 88.49 ±â€¯2.35, 76.80 ±â€¯1.68 µg/mL, respectively), α-amylase (IC50 107.65 ±â€¯12.64, 95.65 ±â€¯2.73 µg/mL, respectively) and lipase (IC50 6.20 ±â€¯0.63, 4.31 ±â€¯0.62 µg/mL, respectively). Furthermore, to the best of our knowledge, this is the first work that carnosic acid standard equivalent inhibition capacities (CAEIC50) for these food samples were determined and these values were in agreement with the IC50 values. These results show that sage and rosemary are potent inhibitors of lipase, α-amylase and α-glucosidase digestive enzymes.

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Ambient mass spectrometry using an interchangeable thermal desorption/electrospray ionization source (TD-ESI) is a relatively new technique that has had only a limited number of applications to date. Nevertheless, this direct-analysis technique has potential for wider use in analytical chemistry (e.g., in the rapid direct detection of contaminants, residues, and adulterants on and in food) when operated in dual-working mode (pretreatment-free qualitative screening and conventional quantitative confirmation) after switching to a TD-ESI source from a conventional ESI source. Herein, we describe the benefits and challenges associated with the use of a TD-ESI source to detect adulterants on traditional Chinese pastries (TCPs), as a proof-of-concept for the detection of illegal colorants. While TD-ESI can offer direct (i.e., without any sample preparation) qualitative screening analyses for TCPs with adequate sensitivity within 30 s, the use of TD-ESI for semi-quantification is applicable only for homogeneous matrices (e.g., tang yuan).

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Chrysin (5,7-dihydroxyflavone) is a natural and biologically active compound which has many biological activities as an anticancer agent. The current report is aimed at finding out whether the antitumor potential of chrysin, evidenced in vitro and in vivo, is linked or not to its effect on immunological mechanisms of melanoma-bearing mice. Chrysin-treated B16F10 cells were analyzed for their metabolic rate and apoptotic potentials. In vivo, BALB/c mice received a subcutaneous injection of B16F10 melanoma cells prior to antitumor treatments with chrysin (50 mg/kg b.w) for 14 days and 21 days. The results showed that chrysin inhibited cancer cell growth at a dose-dependent manner by inducing apoptosis and cell cycle arrest at G2/M phase. Moreover, chrysin suppressed melanoma tumor growth at an average of 60% (after 14 days of treatment) and 71% (after 21 days of treatment) compared to the tumor-bearing group. Furthermore, chrysin treatment increased the cytotoxic activity of NK, CTL and macrophages. The findings showed that chrysin antitumor action on the murine melanoma model was very promising, suggesting that chrysin could be a potentially good candidate for future use in alternative anti-melanoma treatments.

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Chronic hyperglycemia is a potent risk factor of abnormal angiogenesis with various tissue diseases. Autophagy, as an alternative cell response, is mostly generated by a vast array of insults. Applying autophagic response contributes to normal cell retrieval circumstance during various insults. We aimed to show whether stimulation/inhibition of autophagy could reduce or exacerbate oxidative status and angiogenic potential in endothelial cells after exposure to 30mM glucose. HUVECs were incubated with the combined regime of 100nM Rapamycin and 30mM glucose over a period of 72h. The effect of rapamycin on cell viability, malondialdehyde levels, and nitric oxide were monitored by convenient assays. Intracellular ROS level was measured by flow cytometric analysis and DCFDA. HUVECs migration and angiogenic properties were assessed using scratch test and tubulogenesis assay. The expression of autophagic modulators LC3, Becline-1 and P62 was measured by using western blotting. Data showed 30mM glucose reduced cell viability, migration and in vitro tubulogenesis and level of ROS and nitric oxide were found to increased (p<0.05). Rapamycin had potential to increase cell survival and significantly decreased the total levels of oxidative stress markers after cell exposure to 30mM glucose (p<0.05). Rapamycin potentially improved the detrimental effect of 30mM glucose on cell migration and tubulogenesis capacity (p<0.05). Effective autophagic response was stimulated by rapamycin by increasing beclin-1, and the LC3-II/I ratio and reducing intracellular P62 level (p<0.05), resulting in the improvement of cell health and function. Together, rapamycin protected HUVECs from damages caused by high glucose concentration. This effect was possibly mediated by autophagy-dependent pathway.

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A green approach using chitosan solution as a novel bio-dispersive agent for the dispersive liquid-liquid microextraction (DLLME) of trace amounts of Cu(II) in edible oils is presented. An emulsion was formed by mixing the oil sample with 300µL of 0.25% (w/v) chitosan solution containing 200µL of 6molL-1 HCl. Deionized water was used to induce emulsion breaking without centrifugation. The centrifuged Cu(II) extract was collected and analyzed using an inductively coupled plasma-optical emission spectrometer. The detection and quantitation limits were 2.1 and 6.8µgL-1, respectively. Trace amounts of Cu(II) in six edible oil samples were tested under optimum conditions for DLLME, with a recovery ranging from 90.3% to 109.3%. Therefore, the new dispersive agent in DLLME offers superior performance owing to the non-toxic nature of the solvent, short extraction time, high sensitivity, and easy operation.

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Chemically crosslinked cotton fabrics may show yellowish appearance, especially citric acid (CA) crosslinked ones. Hydrogen peroxide (H2O2) bleaching under alkaline condition could improve the whiteness of the CA-crosslinked cotton fabrics but sacrificing certain crosslinking performance of the products due to alkaline hydrolysis of ester connections. Regular H2O2 and UV irradiation (H2O2/UV) system can destroy color but also damage fibers due to the use of very short wavelength of UVC such as 254nm or shorter. Now, it was found that longer wavelength UV such as 312nm performed better in H2O2/UV systems on CA-crosslinked cotton fabrics. The reaction mechanism and potential product of the oxidation reaction on CA-crosslinked cotton were proposed and demonstrated. UV-vis spectrophotometer and Fourier transform infrared spectroscopy provided key evidence. Whiteness, wrinkle recovery angle and tensile strength of the fabrics were evaluated, and the results support the mechanism. The process is environmentally friendly and highly efficient.

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An on-line preconcentration method combining micelle to solvent stacking (MSS) with field-amplified sample stacking (FASS) was employed for the analysis of trimethoprim (TMP) and sulfamethoxazole (SMZ) by capillary zone electrophoresis (CZE). The optimized experimental conditions were as followings: (1) sample matrix, 10.0mM SDS-5% (v/v) methanol; (2) trapping solution (TS), 35mM H3PO4-60% acetonitrile (CH3CN); (3) running buffer, 30mM Na2HPO4 (pH=7.3); (4) sample solution volume, 168nL; TS volume, 168nL; and (5) 9kV voltage, 214nm UV detection. Under the optimized conditions, the limits of detection (LODs) for SMZ and TMP were 7.7 and 8.5ng/mL, and they were 301 and 329 times better compared to a typical injection, respectively. The contents of TMP and SMZ in animal foodstuffs such as dairy products, eggs and honey were analyzed, too. Recoveries of 80-104% were acquired with relative standard deviations of 0.5-5.4%.

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This work demonstrates the successful application of an on-cartridge derivatisation procedure for facile, fast and sensitive determination of formaldehyde in beer by HPLC-UV. The derivatisation and solid-phase extraction (SPE) were integrated into a novel calixarene SPE sorbent: tetraazacalix[2]arene[2]triazine bonded silica gel. Specifically, 2,4-dinitrophenylhydrazine was adsorbed onto the sorbent in advance, based on the charge-transfer interaction between the macrocyclic molecule and nitrobenzenes. The method was optimised and validated: under the optimal conditions of derivatisation, SPE and HPLC separation, good linearity was obtained in the range of 0.080-3.2µgmL(-1) with a correlation coefficient of 0.9939, the limit of detection was 3.0ngmL(-1) (S/N=3), the limit of quantification was 10ngmL(-1) (S/N=10), and the recovery level using this method was desirable at 75-84%. The developed method was successfully applied to determine formaldehyde content in real beer samples; the results were in the range of 0.11-1.1µgmL(-1).

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This study aims to clarify the roles played by endogenous small molecular components in soymilk coagulation process and the properties of gels. Soymilk samples with decreasing levels of small molecules were prepared by ultrafiltration, to reduce the amount of phytate and salts. CaSO4-induced coagulation process was analyzed using rheological methods. Results showed that removal of free small molecules decreased the activation energy of protein coagulation, resulting in accelerated reaction and increased gel strength. However, too fast a reaction led to the drop in storage modulus (G'). Microscopic observation suggested that accelerated coagulation generated a coarse and non-uniform gel network with large pores. This network could not hold much water, leading to serious syneresis. Endogenous small molecules in soymilk were vital in the fine gel structure. Coagulation rate could be controlled by adjusting the amount of small molecules to obtain tofu products with the optimal texture.

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The effect of different concentrations (0, 0.1 and 0.5%, v/v) of black pepper essential oil (BPEO) on thiobarbituric acid reactive substances (TBARS), meat color, the percentage of metmyoglobin (MetMb%), microbiological parameters and total volatile basic nitrogen (TVB-N) of pork loins stored at 4°C for 9days was evaluated. BPEO treatments showed lower TBARS, MetMb%, yellowness (b*) values, Pseudomonas spp. and Enterobacteriaceae count and TVB-N values and higher lightness (L*) and redness (a*) values than the control during storage; the effectiveness of BPEO was dose-dependent. The retardation of the formation of MetMb by adding BPEO ensured higher L* and a* values and lower b* values than the control at 6 and 9days; the MetMb content has a similar trend to the lipid oxidation. The lower TVB-N value of BPEO treatments than the control could be attributed to the inhibition of Pseudomonas spp. and Enterobacteriaceae. Gram-negative bacteria were more sensitive than Gram-positive bacteria to BPEO.

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This study evaluated the effects of alkali extraction, enzymatic hydrolysis, shear emulsifying assisted enzymatic hydrolysis, and particle size distribution on the chemical composition and the structural, physicochemical, and functional properties of deoiled cumin dietary fibers (AEDF, EHDF and SEDF). Compared to AEDF and EHDF, SEDF had the highest total dietary fiber, crystalline regions, water swelling capacity (6.79-7.98ml/g), oil adsorption capacity (6.12-7.25%), α-amylase activity inhibition ratio (14.79-21.84%), glucose adsorption capacity (2.02-60.86%), and bile acid retardation index (16.34-50.08%). DFs sieved with mesh sizes >80 exhibited better physicochemical and functional properties than unsieved DFs. The physicochemical properties of sieved DFs improved with increasing sieve mesh sizes (40-120), but decreased with sieve mesh sizes >120, while the functional properties increased with increasing sieve mesh sizes. SEDF sieved with mesh sizes 100-150 can be used as functional ingredients due to its excellent physicochemical and functional properties.

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1,2,3,4-Butanetetracarboxylic acid (BTCA) reacts with cellulose in two steps with catalysis of alkaline salts such as sodium hypophosphite: anhydride formation and esterification of anhydride with cellulose. The alkali metal ions were found effective in catalyzing formation of BTCA anhydride in a previous report. In this work, catalytic functions of the alkaline salts in the esterification reaction between BTCA anhydride and cellulose were investigated. Results revealed that acid anions play an important role in the esterification reaction by assisting removal of protons on intermediates and completion of the esterification between cellulose and BTCA. Besides, alkaline salts with lower pKa1 values of the corresponding acids are more effective ones for the reaction since addition of these salts could lead to lower pH values and higher acid anion concentrations in finishing baths. The mechanism explains the results of FTIR and wrinkle recovery angles of the fabrics cured under different temperatures and times.

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In this study we present the development of an injectable polymeric drug delivery system for subconjunctival treatment of primary open angle glaucoma. The system consists of hyaluronic acid sodium salt (HA), which is commonly used in ophthalmology in anterior segment surgery, and an isocyanate-functionalized 1,2-ethylene glycol bis(dilactic acid) (ELA-NCO). The polymer mixtures with different ratios of HA to ELA-NCO (1/1, 1/4, and 1/10 (v/v)) were investigated for biocompatibility, degradation behavior and applicability as a sustained release system. For the latter, the lipophilic latanoprost ester pro-drug (LA) was incorporated into the HA/ELA-NCO system. In vitro, a sustained LA release over a period of about 60days was achieved. In cell culture experiments, the HA/ELA-NCO (1/1, (v/v)) system was proven to be biocompatible for human and rabbit Tenon's fibroblasts. Examination of in vitro degradation behavior revealed a total mass loss of more than 60% during the observation period of 26weeks. In vivo, LA was continuously released for 152days into rabbit aqueous humor and serum. Histological investigations revealed a marked leuko-lymphocytic infiltration soon after subconjunctival injection. Thereafter, the initial tissue reaction declined concomitantly with a continuous degradation of the polymer, which was completed after 10months. Our study demonstrates the suitability of the polymer resulting from the reaction of HA with ELA-NCO as an injectable local drug delivery system for glaucoma therapy, combining biocompatibility and biodegradability with prolonged drug release.

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