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Liu Q.-C.,Northwest University, China | Guo T.-T.,Xian Institute for Food and Drug Control | Zhao C.,Northwest University, China | Sun J.,Northwest University, China | Li W.-H.,Northwest University, China
Helvetica Chimica Acta | Year: 2014

Chemical synthesis of a trisaccharide related to the cytotoxic triterpenoid saponins isolated from the bark of Albizia procera has been accomplished through a concise stepwise glycosylation strategy starting from commercially available D-xylose, 2-acetamido-2-deoxy-D-glucose and L-arabinose. The target trisaccharide was designed with a 4-methoxyphenyl (MP) aglycone to extend the scope of conversion to suitable glycoconjugates via selective removal of 4-methoxyphenyl (MP) group. An unexpected phenomenon, i.e., the arabinosyl residue assumed the 1C4 conformation instead of the typical 4C1 form, was observed. Deprotection could restore the normal conformation. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich. Source

Wang H.,Nanjing Agricultural University | Shu R.,Xian Institute for Food and Drug Control | Zhao Y.,Nanjing Agricultural University | Zhang Q.,Nanjing Agricultural University | And 2 more authors.
European Food Research and Technology | Year: 2014

The chicken slaughter line is a source of cross-contamination of Salmonella. In this study, ERIC-PCR was applied to analyse the ERIC-PCR genomic polymorphism of Salmonella isolates from a commercial chicken slaughter line and to trace the route of contamination. Samples were collected from carcasses and contact surfaces at the points of post-evisceration, post-chilling and post-grading. The prevalence of Salmonella at the evisceration point was high but significantly decreased along the slaughter line. The ERIC-PCR fingerprints indicated that a total of seven groups were clustered, and the genotypic diversity of isolates progressively decreased along the slaughter line. By tracing the genotypic diversity, contact surfaces at post-evisceration were found to be the major contamination sources of Salmonella during chicken processing, since the genotype diversity of isolates from the post-evisceration point could be exactly matched to that from the post-chilling and post-grading points. Interestingly, three Salmonella strains were still detected after decontamination and washing; these three isolates having a strong capacity for attachment were able to produce biofilm on polystyrene surfaces. This study suggests that the evisceration point is the source of cross-contamination, with Salmonella isolates still present after washing procedure. Therefore, more effective measures must be undertaken to control the spread of Salmonella in such processing lines. © 2014 Springer-Verlag Berlin Heidelberg. Source

Sun J.,Peking Union Medical College | Wu Y.-Z.,Nanjing Medical University | Wang S.,Xian Institute for Food and Drug Control | Wang J.,Peking Union Medical College | And 2 more authors.
Chinese Traditional and Herbal Drugs | Year: 2013

Objective: To study the dissolving yield and ratio fluctuation of Sparganii Rhizoma effective composition groups, including total flavonoids, total alkaloid, and active Al3+, when processed with different vinegar processing technologies. Methods: L9(34) orthogonal test design was used with acetic acid content (A), vinegar ratio (B), soaking time (C), and frying temperature (D) as influencing factors. The differences of dissolving yield and ratio of 80% methanol extract, total flavonoids, total alkaloid, and active Al3+ of processed Sparganii Rhizoma under different vinegar processing technologies were compared. Results: Compared with crude Sparganii Rhizoma, the processed products with a little acetic acid had enhanced the dissolving yield of 80% methanol extract. Moreover, the processed Sparganii Rhizoma with vinegar had effectively enhanced the dissolving yield and ratio of total flavonoids, total alkaloid, and active Al3+. The dissolving yield and ratio of total flavonoids were greatly impacted by frying temperature. Meanwhile, the alkaloid dissolving yield and ratio were most influenced by acetic acid content. The products processed with abundant acetic acid had obviously reduced the dissolving yield of 80% methanol extract, but had increased the alkaloid and active Al3+ dissolving ratio in the extract. Conclusion: The processed Sparganii Rhizoma with vinegar could obviously affect the dissolving yield and ratio of different pharmacodynamic compositions in Sparganii Rhizoma. Suitable processed products should be adopted when Sparganii Rhizoma is used in the different treatments. Source

Hou B.,Northwest University, China | Ai Y.,Northwest University, China | Ai Y.,Xian Institute for Food and Drug Control | Wang C.,Northwest University, China | And 4 more authors.
Chinese Journal of Organic Chemistry | Year: 2016

The isatin derivatives 4a~4f were prepared and underwent oxidative hydrolysis to give the anthranilic acid 5a~5d. A and/or D-ring substituted tryptanthrins were designed and synthesized from 4a~4f to 5a~5d. Then C-ring Schiff bases of tryptanthrin were synthesized by condensation of 6-carbonyl with hydrazine and hydroxylamine hydrochloride. Finally, the B-ring was replaced with piperazine to give 11H-indeno[1,2-b]quinoxalin-11-one. 20 compounds were synthesized and their structures were confirmed by 1H NMR, IR and elemental analysis. To best of our knowledge, 13 of them were unknown in the literature. The antitumor activities of synthesized compounds were evaluated against A549 cell line in vitro. The preliminary results indicated that 1b, 1c, 1i, 1j, 1p and 1q showed good antitumor activity with the IC50 of 3.58, 0.99, 1.03, 2.10, 0.51 and 0.43 μmol·L-1, respectively. Structure-activity relationship showed that halogen substitution located in the D-ring enhanced the anti-tumor activity, while the same substitution located in the A ring reduced the activity. The anti-tumor activity disappeared when B-ring was replaced by piperazine, while there was no significant difference for tryptanthrin and its C-ring Schiff base. © 2016 Chinese Chemical Society & SIOC, CAS. Source

Du H.,Xian Jiaotong University | Du H.,Xian Institute for Food and Drug Control | Lv N.,Xian Jiaotong University | Wang S.,Xian Jiaotong University | He L.,Xian Jiaotong University
Combinatorial Chemistry and High Throughput Screening | Year: 2013

A new high-expression endothelial growth factor receptor (EGFR) cell membrane chromatography (CMC) method was applied to recognize the ligands acting on EGFR specifically, and investigate the affinity of gefitinib/HMQ1611 to EGFR. In the self and direct competitive assay, gefitinib/HMQ1611 was used as a competitor in the mobile phase to evaluate the effect of the competitor's concentrations on the retention of the ligands, respectively, and the competition between gefitinib and HMQ1611 binding to EGFR was also been examined. The retention behavior indicated that gefitinib had one type of binding sites on the EGFR, and the equilibrium dissociation constant (K D) was (9.11 ± 1.89) × 10-6 M; HMQ1611 had two major binding regions on the EGFR, and the KD values obtained from the model were (2.39 ± 0.33) × 10-7 and (3.87 ± 0.93) × 10-5 M for HMQ1611 at the high- and low-affinity sites, respectively. The competition between gefitinib and HMQ1611 occurred at the low-affinity sites on the EGFR. The low-affinity sites were of higher concentrations and contributed to a much larger part of retention of HMQ1611. The results suggested that gefitinib and HMQ1611 competed for the common binding sites on the EGFR, no matter the ligand was used as an analyte or a competitor. © 2013 Bentham Science Publishers. Source

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