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Abstract: The contents of 12 ginsenosides (Rg1, Re, F11, Rf, Rg2, Rh1, Rb1, Rc, Rb2, Rb3, Rd, Rh2) in different parts and ages of Panax quinquefolius L. (American ginseng) were quantified by high pressure microwave-assisted extraction (HPMAE) high-performance liquid chromatography coupled with evaporative light scattering detection (HPLC-ELSD). The analytical method was established and analytical performances were evaluated. The chemical marker of American ginseng F11 was detected, and Rf which is the chemical marker of Asian ginseng was not found. Rare ginsenoside Rh1, Rg2 and Rh2 were also studied in this experiment. The total contents of these 12 ginsenosides in the different parts of 5-year-old American ginseng follow this order: leaf>root-hair>rhizome>root>stem. Therefore, compared with the other parts of American ginseng, the leaf is a better available source of ginsenosides. The contents of ginsenosides in root and leaf also change with age. [Copyright &y& Elsevier]

In this study, glycosylated gluten was modified to form a glycosylated gluten covalent complex. The covalent complex then forms nanoparticles through self-assembly under heating to stabilize the Pickering emulsion. The emulsion was loaded with β-carotene to investigate its protective effects on carotene. The research findings showed the thermal and storage stability of Pickering emulsion was the best when the concentration of glycosylated gluten nanoparticles was 4 % and oil-water volume was 40 %. Under these conditions, the smallest and most uniform distribution of emulsion droplets was observed using scanning electron microscopy (SEM) and particle size analysis. Confocal laser scanning microscopy (CLSM) confirmed that the glycosylated gluten nanoparticles formed a three-dimensional network through their interactions at the oil-water interface, inhibited droplet aggregation, and increased the stability of the emulsion. Through simulated digestion in vitro, confirmed β-carotene can be well protected by the prepared Pickering emulsion. • The hydrophilicity of gluten protein was improved by glycosylation. • Glycosylated gluten is heated to form nanoparticles to stabilize Pickering emulsion. • CLSM confirmed that the nanoparticles increased the stability of the emulsion. • In vitro digestion model found that the β-carotene can be protected by the emulsion. [ABSTRACT FROM AUTHOR]

Abstract Deoxynivalenol (DON), Fumonisin B 1 (FB 1) and Aflatoxin B 1 (AFB 1) have strong toxicity to humans and exist widely in grain and food. It is necessary to screen these mycotoxins to guarantee food safety. In order to develop a rapid, simple, low-cost and simultaneous-detection method, composites of antibody-nano-Au-particles, DON-BSA, FB 1 -BSA, and AFB 1 -BSA were prepared to establish a lateral flow assay based on competitive inhibition. The results suggested that the visual detection limits for DON, FB 1 and AFB 1 were 10, 30, and 10 ng mL−1, respectively. On the other hand, it had no reactivity to T-2 toxin, zearalenone, ochratoxin A and nivalenol, which demonstrates good specificity. Besides, the strip had good repeatability and stability. Therefore, DON, FB 1 and AFB 1 would be screened simultaneously by lateral flow assay for food safety. Highlights • A lateral flow assay for simultaneous detection of DON, FB 1 and AFB 1. • The visual detection limit was down to 10 ng mL−1. • The assay showed high stability and specificity. [ABSTRACT FROM AUTHOR]

Abstract: High pressure microwave assisted extraction (HPMAE) was applied to extract the ginsenosides from Panax ginseng root. The influences of extraction solvent, extraction pressure and extraction time were individually investigated. HPMAE has been compared with other extraction methods, including Soxhlet extraction, ultrasound-assisted extraction and heat reflux extraction. The determination of ginsenosides was performed by HPLC–ESI-MS. The results indicated that the HPMAE not only took a shorter time but also afforded higher extraction yields of ginsenosides, especially ginsenoside Rb1, Rc, Rb2 and Rd. Furthermore, the neutral ginsenosides and malonyl ginsenosides in Panax ginseng root extracts by HPMAE were investigated. The malonyl ginsenoside m-Rb1, m-Rc, m-Rb2 and m-Rd degraded in HPMAE at 400kPa (109–112°C) in 70%(v/v) ethanol–water and at 600kPa (112–115°C) in methanol, and transformed into corresponding neutral ginsenoside Rb1, Rc, Rb2 and Rd. Using water as extraction solution, the neutral ginsenosides degraded under HPMAE at 400kPa (135–140°C), and transformed into less polarity rare ginsenosides. [Copyright &y& Elsevier]

Abstract: The HPLC coupled with electrospray ionization mass spectrometry (ESI-MS) was applied for the determination of tributyltin chloride (TBT), triphenyltin chloride (TPhT), triethyltin chloride (TET) in textile and plastic samples. The separation was performed in the isocratic mode on ion exchange SCX column with a mobile phase containing methanol–ammonium acetate (50mmoll−1)–acetic acid (90/9.98/0.02, v/v/v). Sensitive detection of three organotin compounds by ESI-MS was performed on the basis of multiple reaction monitoring (MRM) mode. Limits of detection were 0.4, 20, 4ngml−1 for TBT, TPhT, and TET, respectively. Microwave-assisted extraction (MAE) of organotin compounds was finished in 60% (v/v) methanol aqueous solution. Under the experimental conditions used, recoveries of three organotin compounds obtained for spiked textile and plastic samples are in the range of 55–95% and the R.S.D.s are 3–9%. [Copyright &y& Elsevier]

Abstract: An apparatus for extraction of flavonoids from Herba Epimedii has been constructed which utilizes a microwave technique for heating in a dynamic mode. A TM010 microwave resonance cavity was applied to concentrate the microwave energy; the power needed to achieve efficient extraction was significantly reduced. The method has been compared with other extraction methods, such as pressurized microwave-assisted extraction (PMAE), ultrasonic extraction (UE), heat reflux extraction (RE) and Soxhlet extraction (SOX). The four flavonoids in extract were identified by HPLC–MS. The influence of extraction parameters on the extraction yield of flavonoids has been evaluated by comparison with the peak areas of HPLC-DAD spectra in the different extraction methods. The results showed that the extraction yield of flavonoids in Herba Epimedii obtained by dynamic microwave-assisted extraction (DMAE) was higher than that obtained by UE, RE and SOX, and the extraction time is dramatically reduced. The extraction yield obtained by DMAE is similar to that obtained by PMAE. But the flavonoids in Herba Epimedii would not decompose easily when increasing the extraction time in DMAE. This is the benefit of dynamic extraction system which can transfer the analytes extracted from the sample matrix with flowed fresh solvent to the out of extraction vessel. [Copyright &y& Elsevier]