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Multifunctional photothermal nanomaterials offer notable opportunities for antimicrobial therapy due to their excellent antibacterial activities without leading to drug resistance. Herein, we report a facile one-step strategy for fabricating anisotropic corn-like α-Fe2O3/AgAu/polydopamine (PDA) nanospindles with photothermally enhanced antibacterial performance. The AgAu bimetallic nanocrystals sandwiched between the α-Fe2O3 core and the PDA shell are achieved by simultaneous reduction from AgNO3 and HAuCl4 during the oxidative polymerization of dopamine and galvanic replacement reaction between the obtained Ag nanocrystals and Au precursor. The inner nanostructure and atom ratio of AgAu bimetallic nanocrystals can be modulated by varying the experimental parameter, thus further controlling the photothermal activities. In comparison to α-Fe2O3/Au/PDA, Fe2O3/Ag1.7Au0.8/PDA (50 μg/mL) has a better photothermal conversion effect (60.69%). Moreover, the α-Fe2O3/Ag1.7Au0.8/PDA nanospindle exhibits moderate antibacterial activity, which may be derived from Ag+ release. Under application of near-infrared light irradiation, the corn-like α-Fe2O3/Ag1.7Au0.8/PDA nanospindles (50 μg/mL) exhibit a photothermally enhanced sterilization effect against both Escherichia coli and Staphylococcus aureus (99.99%). This "Ag+ release–photothermal" coupling sterilization method provides a simple synergistic antimicrobial therapy strategy, which possesses great promise for future nanomedicine against bacteria in water treatment. [ABSTRACT FROM AUTHOR]

Due to the abuse of antibiotics, the sensitivity of patients to antibiotics is gradually reduced. This work develops a Fe3O4@SiO2@Au/PDA nanochain which shows an interesting magnetic-field-induced improvement of its photothermal antibacterial property. First, SiO2 was wrapped on Fe3O4 nanospheres assembled in a chain to form a Fe3O4@SiO2 nanocomposite with a chain-like nanostructure. Then, the magnetic Fe3O4@SiO2@Au/PDA nanochains were prepared using in situ redox-oxidization polymerization. Under the irradiation of an 808 nm NIR laser, the temperature rise of the Fe3O4@SiO2@Au/PDA nanochain dispersion was obvious, indicating that they possessed a good photothermal effect. Originating from the Fe3O4, the Fe3O4@SiO2@Au/PDA nanochain showed a typical soft magnetic behavior. Both the NIR and magnetic field affected the antimicrobial performance of the Fe3O4@SiO2@Au/PDA nanochains. Escherichia coli and Staphylococcus aureus were used as models to verify the antibacterial properties. The experimental results showed that the Fe3O4@SiO2@Au/PDA nanochains exhibited good antibacterial properties under photothermal conditions. After applying a magnetic field, the bactericidal effect was further significantly enhanced. The above results show that the material has a broad application prospect in inhibiting the growth of bacteria. [ABSTRACT FROM AUTHOR]

In this article, novel molecularly imprinted polymers based on 3D reduced graphene oxide aerogel (3D RGO‐GBMIPs) were successfully fabricated and applied as adsorbents for dispersed solid‐phase extraction (DSPE) of ginkgolide B (GB). After being prepared by surface molecular imprinted technology, 3D RGO‐GBMIPs were successively characterized by fourier transform infrared spectroscopy, thermogravimetric analysis, Raman spectroscopy, and scanning electron microscope. The results of adsorption experiments revealed that 3D RGO‐GBMIPs presented highly selective recognition properties and well reusability. The main variables influencing DSPE efficiency, including extraction solvent, 3D RGO‐GBMIPs dosage, category, and volume of eluent, as well as elution time were investigated. The DSPE results showed that 3D RGO‐GBMIPs had an obvious effect on the improvement of GB purity in ginkgo biloba extract, with a satisfactory recovery rate and yield. Therefore, 3D RGO‐GBMIPs are expected to be applied for the enrichment of GB from complex matrices. [ABSTRACT FROM AUTHOR]

Infectious diseases associated with drug-resistant bacteria increasingly threaten public health. Effective antibacterial nanoplatforms are of special importance for treating bacterial infections. In this work, a novel magnetic Fe3O4–Au–PDA hybrid microcapsule with both photothermal (PTT) and photodynamic (PDT) anti-bacterial functions was developed. First, the Fe3O4@Au/PDA core/shell microspheres with hollow nature were obtained by a simple in situ redox–oxidize polymerization method. Then, they were etched in acid to improve the hollow interior and porous shell. Finally, the tetracarboxyzinc phthalocyanine (ZnPc) was used as the photosensitizer to be loaded into the above Fe3O4–Au–PDA hybrid microcapsule. Owing to the dual-mode photothermal Au–PDA hybrid shell and the ZnPc photosensitizer, the final Fe3O4–Au–PDA/ZnPc hybrid microcapsule serves as a wonderful photothermal/photodynamic (PTT/PDT) synergistic therapy agent. The experimental results show that the Fe3O4–Au–PDA/ZnPc microcapsule possesses excellent photothermal sterilization effect (808 nm laser irradiation) against Escherichia coli, and the experimental results further demonstrate good photodynamic behavior under Xenon lamp irradiation. The product exhibits much higher antibacterial performance by combining the PTT/PDT treatment, which demonstrates that this work provides a novel dual-mode phototheranostic nano-agent for an effective treatment of bacterial infections. [ABSTRACT FROM AUTHOR]

In this study, the physico-chemical properties of tomato powder produced by an optimized freeze drying process (FDP) were evaluated. With the lycopene content as the dependent variable, the optimum FDP conditions (i.e., thermal cracking time of 62 s, ascorbic acid addition amount [0.13%], and particle size [Dv90] of 163 μm) were obtained through response surface methodology (RSM). The results showed that the content of lycopene in the prepared tomato powder was higher than that in two commercial products. Aldehydes were the main components among 25 kinds of aromatic substances detected in tomato powder. The values of a* and a*/b*, the hydration properties including water holding capacity (WHC) and oil binding capacity (OBC), and the content of total acid, ascorbic acid, and soluble solids were improved compared to commercial spray dried and freeze dried samples. All the above results suggested that FDP was an adequate procedure for the production of high-quality tomato powder. [ABSTRACT FROM AUTHOR]

BACKGROUND: The poor palatability, low digestibility, and unpleasant color of parboiled rice (PR) have severely hampered its acceptance by consumers. It is hence necessary and urgent to develop a new method for producing high‐quality PR. In the current study, the effect of high hydrostatic pressure (HHP) pre‐soaking on the color, textural properties, and the degree of retrogradation of PR was investigated. RESULTS: With HHP from 100 to 500 MPa, the water adsorption rate increased and cooking time decreased. Parboiled rice samples presented higher lightness scores (L) and had lower color intensity (B). Compared with a control group, PR samples treated with high‐pressure pre‐soaking showed a reduction of hardness values from 0.69% to 32.99%, and gumminess values also decreased from 8.58% to 33.62%. The differential scanning calorimetry (DSC) results indicated that the enthalpy values of PR samples decreased after high pressure pre‐soaking. The molecular structure of PR characterized by Fourier transform infrared spectrometry confirmed that HHP pre‐soaking could decrease the retrogradation level. CONCLUSION: The findings outlined above suggest that the texture and retrogradation properties of PR were improved after high‐pressure pre‐soaking. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Protecting the intestinal mucosa from being destroyed helps reduce the inflammation caused by acute pancreatitis (AP). In this study, whether okra pectin (OP) could attenuate the inflammation of AP through protecting the intestinal barrier was investigated. RESULTS: OP was obtained from crude okra pectin (COP) through the purification by DEAE cellulose 52 column. Supplementation with OP or COP in advance reduced the severity of AP, as revealed by lower serum amylase and lipase levels, abated pancreatic edema, attenuated myeloperoxidase activity and pancreas histology. OP or COP inhibited the production of pancreatic proinflammatory cytokines, including tumor necrosis factor‐α and interleukin‐6. In addition, the upregulation of AP‐related proteins including ZO‐1, occludin, the antibacterial peptide‐defensin‐1 (DEFB1) and cathelicidin‐related antimicrobial peptide (CRAMP), as well as the histological examination of colon injuries, demonstrated that OP or COP provision could effectively maintain intestinal barrier function. Ultimately, dietary OP or COP supplementation could inhibit AP‐induced intestinal inflammation. For the above, the effect of OP was better than COP. CONCLUSION: Dietary OP supplementation could be considered as a preventive method that effectively interferes with intestinal damage and attenuates inflammatory responses trigged by AP. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The effect of high hydrostatic pressure (HHP) on pasting properties, volatile flavor components, and water distribution of cooked black rice (BR) was investigated. BR samples were subjected to HHP treatments at 200, 300, 400, and 500 MPa for 15 min, and then cooked for further evaluation. Results showed that HHP‐treated samples exhibited lower viscosity compared to the control group, with the lowest value at 500 MPa. Among 126 flavor compounds identified in cooked BR stored for 7 days, the total contents of three key flavor components (alcohols, ketones, and aldehydes) were greatly enhanced, indicating that HHP contributed to the aroma quality of cooked BR. Water characteristics were determined by low‐field nuclear magnetic resonance (LF‐NMR), and three water fractions were detected and identified as T21, T22, and T23. The value of T21 gradually decreased with the increase of pressure, suggesting that HHP reduced the retrogradation degree of cooked BR. Practical applications: This paper provides information on the potential benefits of HHP processing on pasting properties, volatile flavor components, and water distribution of cooked BR. Our results demonstrated that HHP‐treated BR samples exhibited lower viscosity in terms of PV, TV, BD, FV, and SB. Considering the aroma quality of cooked BR, HHP, as an effective food processing technology, has the potential to retain flavor compounds in food. Therefore, this study would provide technical support for the commercial application of HHP‐treated cooked BR. [ABSTRACT FROM AUTHOR]

A rapid and robust preparation method of six isoflavones from ethanol aqueous extract of Iris tectorum Maxim (I. tectorum) was established by using macroporous resin column chromatography and preparative high-performance liquid chromatography (Prep-HPLC). After separation by AB-8 resins, total flavonoids content increased from 10.60% in the crude extract to 54.20% with a recovery yield of 75.12%. Subsequently, the extracts were purified by Prep-HPLC, and the purities were more than 82.2% after assessment by analytical HPLC and characterization by mass spectrometry. The established method is expected to be used for preparing available quantities of pure isoflavones from I. tectorum. [ABSTRACT FROM AUTHOR]

Ginkgolide B is in great demand worldwide on account of its extensive and excellent pharmacological effects, however, it is difficult to separate and purify ginkgolide B. In this study, ginkgolide B molecularly imprinted polymers were prepared by combining software simulation and molecular imprinting technique, and its characterization and adsorption performed evaluation were performed to understand the adsorption behavior of the polymers. The adsorption equilibrium concentration of molecularly imprinted polymers was 0.70 mg/mL, and the adsorption equilibrium time was 4 h. Meanwhile, the adsorption isotherm of the polymers for ginkgolide B fitted well with the Langmuir model, and the adsorption kinetics was in line with the pseudo‐second‐order kinetics. In contrast, the adsorption capacity of molecularly imprinted polymers on ginkgolide B was higher than that of non‐molecular imprinted polymers, with better selectivity and better adsorption after repeated use for six times. The application experiments showed that molecular imprinted polymers have a good adsorption effect in low purity samples. Therefore, the polymers reported herein can be expected to apply in the adsorption and separation of ginkgolide B samples. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF)-derived nanostructures exhibit wonderful characteristics and possess broad application potential by modulating the complex composition and inner nanostructure. Although various MOF-based nanocomposites have been successfully developed, a facile method that can easily modulate the structure-dependent chemical components of the MOF-derived hybrids remains a challenge. By coating zeolitic imidazolate framework-8 (ZIF-8) with Au/polydopamine (Au/PDA) via in situ redox-oxidation polymerization of HAuCl4 and dopamine, it was found that the ZIF-8 templates were simultaneously etched off to give Au/PDA hybrid microcapsules with a cubic shape. This one-step sacrificial templating process followed a competing chelation between gold ions and Zn2+ cations to 2-methylimidazole and PDA; thus, both the hollow and the yolk-like hybrid cubic microcapsules were controllably obtained by varying the synthetic dynamics. Owing to the hollow nature, penetrated PDA shell, well-distributed Au nanocrystals, and unique stable nanostructure, the non-spherical Au/PDA hybrid cubic microcapsules showed high performance in catalyzing the reduction of 4-nitrophenol as well as adsorption/release of ibuprofen as a model drug. Moreover, this simple strategy offers a controllable design in developing multifunctional nanocomposites with definite inner nanostructures and activities for nanocatalysis, drug delivery, energy storage etc. [ABSTRACT FROM AUTHOR]

The purpose of this study was to optimize the preparation conditions of podophyllotoxin liposomes (PPT-Lips), and to investigate their effects on PC3 cells. PPT-Lips were prepared by using a thin-film dispersion method. In order to achieve maximum drug encapsulation efficiency (EE), the process and formulation variables were optimized by response surface methodology (RSM). The optimum preparation conditions were cholesterol to lecithin ratio of 3.6:40 (w/w), lipid to drug ratio of 15.8:1 (w/w), and the ultrasonic intensity of 35% (total power of 400 W). The experimental EE of PPT-Lips was 90.425%, which was consistent with the theoretically predicted value. The characterization studies showed that PPT-Lips were well-dispersible spherical particles with an average size of 106 nm and a zeta potential of –10.1 mV. A gradual and time-dependent pattern of PPT from liposomes was found in in vitro drug release with a cumulative release amount up to 70.3% in 24 h. Results of cell viability experiments on PC3 cells demonstrated that PPT-Lips exhibited more effective anticancer activity in comparison with free PPT. Therefore, PPT-Lips represent an efficient and promising drug delivery system for PPT. [ABSTRACT FROM AUTHOR]

Tetramethylpyrazine was introduced to the structure of danshensu (DSS) as P-glycoprotein (P-gp)-inhibiting carrier, designing some novel brain-targeting DSS-pyrazine derivatives via prodrug delivery strategy. Following the virtual screening, three DSS-pyrazine esters (DT1, DT2, DT3) were selected because of their better prediction parameters related to brain-targeting. Among them, DT3 was thought to be a promising candidate due to its appropriate bioreversible property in vitro release assay. Further investigation with regard to DT3’s brain-targeting effects in vivo was also reported in this study. High-performance liquid chromatography-diode array detection (HPLC-DAD) method was established for the quantitative determination of DT3 and DSS in rat plasma, brain homogenate after intravenous injection. In vivo metabolism of DT3 indicated that it was first converted into DT1, DT2, then the generation of DSS, which could be the result of carboxylesterase activity in rat blood and brain tissue. Moreover, the brain pharmacokinetics of DT3 was significantly altered with 2.16 times increase in half-life compared with that of DSS, and its drug targeting index (DTI) was up to 16.95. Above these data demonstrated that DT3 had better tendency of brain-targeting delivery, which would be positive for the treatment of brain-related disorders. [ABSTRACT FROM AUTHOR]

An efficient preparation procedure has been proposed for the synthesis of 5,6-di-O-cinnamyl- l-ascorbic acid ester (5,6-CA-AA) and 2-O-cinnamyl- l-ascorbic acid ester (2-CA-AA) via ascorbic acid (AA) and cinnamic acid (CA), and their anti-oxidant and antibacterial activities were also investigated. Among the factors affecting the synthesis efficiency of 5,6-CA-AA and 2-CA-AA, reaction solvent and substrate molar ratio were very important, resulting in 76 and 54% total yield, respectively. Further studies indicated that 5,6-CA-AA maintained the inherent inhibitory ability of AA in α, α-diphenyl-β-picrylhydrazyl radical scavenging assay. Also, it had stronger scavenging activity against hydroxyl radicals than that of standard tert-butylhydroquinone (EC: 7.84 vs. 8.38 mM). In addition, 5,6-CA-AA and 2-CA-AA possessed comparable antibacterial activity to that of CA. Significantly, the application of ascorbyl cinnamate could retard the lipid oxidation of peanut oil and pork, and the corresponding perioxide value and thiobarbituric acid reactive substance content decreased by 32.0 and 56.5%, respectively. Moreover, the microbial reproduction of the pork treated with mixed ascorbyl cinnamate was attenuated to some extent. These investigations will pave the way for designing more efficient bifunctional derivatives of AA and CA. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A sensitive, simple and rapid liquid chromatography–tandem mass spectrometry method was developed and validated for the simultaneous determination of ginkgolide B (GB) and the prodrug of ginkgolide B (PGB) in rat plasma and brain tissue. Detection was performed on a triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode using the electrospray ionization technique in negative ionization mode. The total run time was only 2.0 min. Good linearity was found between 1–200 ng/mL (r > 0.9993) for plasma samples and 0.5–50 ng/mL (r = 0.9995) for the brain tissue samples. The lower limits of quantification of PGB and GB were 1 ng/mL for plasma and 0.5 ng/mL for brain tissue. Intra-day and inter-day precision was less than 11.67%. Intra-day accuracy was in the range of –2.61–10.67%, inter-day accuracy was in the range of –2.36–8.98%. The mean recovery for PGB and GB was between 82.5 and 97.0%. The validated method was successfully applied to a pharmacokinetic study of PGB and GB in rats after intravenous administration. [ABSTRACT FROM PUBLISHER]

The preparation of new sulfonamide ligands derived from L-tartaric acid and camphor sulfonyl chloride are described. The employment in the titanium tetraisopropoxide-promoted enantioselective addition of diethylzinc to ketones has been studied. The best enantiomeric excess is up to 99% with 7 mol% catalyst loading at room temperature. [ABSTRACT FROM AUTHOR]

In this study, the preparation of molecularly imprinted polymers for bilobalide (BBMIPs) was successfully achieved by bulk polymerization with methacrylamide (MAM), trimethylolpropane triacrylate (TMPTA), and acetonitrile (ACN) as functional monomer, cross-linker, and solvent, respectively. After Gaussian software simulation and single factor experiments, the prepared MIPs with a molar ratio of 1:4:15 for BB-MAM-TMPTA were systematically characterized. The hydrogen bonding interaction between BB and MAM was confirmed by a combination of FTIR and NMR analysis. Thermal gravimetric analysis results displayed that MIPs have excellent thermal stability under high temperature. Additionally, the average pore size and surface area of MIPs were found to be higher than those of NIPs through nitrogen adsorption results. The results of static adsorption and kinetic adsorption suggested that the adsorption equilibrium concentration was 0.6 mg/mL and the equilibrium time was 5 h, and the Langmuir and pseudo-second-order kinetic models were proven to fit with static and kinetic adsorption behaviors, respectively. Meanwhile, the selective adsorption study revealed that MIPs show high adsorption and great selectivity towards BB in comparison with other substances having similarly structure. MIPs also possessed a good performance on reusability, maintaining a high recovery rate after being reused 5 times. The application experiment further indicated that MIPs can effectively separate BB from low purity samples. Therefore, the prepared MIPs had a great potential for BB separation. [ABSTRACT FROM AUTHOR]