ABSTRACT
@#To investigate the freshness, high molecular weight substances, the determination of polypeptide, haemolysis and agglomeration, biological activity of Cervus and Cucumis polypeptide injection; to provide the direction for improving the quality of products for enterprises; furthermore, to provide reference for the revision of the quality standards of Cervus and Cucumis polypeptide injection. Firstly, we investigated the factors affecting the freshness of the injection, including biogenic amines, aflatoxins, the acid value and peroxide value of the melon seeds. The method of dansyl chloride pre-column derivatization-HPLC was used to determine the content of 8 biogenic amines in Cervus and Cucumis polypeptide injection. The method validation results showed good specificity, precision, linearity and recovery rates, which was suitable for the determination of biogenic amines in Cervus and Cucumis polypeptide injection. The results of sample determination showed that relatively higher concentrations of cadaverine were detected in the products from company B. The results of aflatoxins, acid value and peroxide value showed that the melon seeds from some companies had rancidity, mildew and other problems, indicating that the quality standards of multi-component biochemical drugs containing animal- and plant-derived components should be controlled in terms of freshness. Secondly, the methods for the determination of high molecular weight substances and polypeptides in the quality standard were improved. Tricine-SDS-PAGE electrophoresis was used instead of gel chromatography to determine the high molecular weight substances, which improved the accuracy of determination. The kits were used instead of folin-phenol for the determination of peptide content, which is easy to operate, specific and suitable for high-throughput sample determination. Finally, the haemolysis, agglomeration, and biological activity of Cervus and Cucumis polypeptide injection were studied. The results showed that no haemolysis and agglomeration were found in all samples, and the inhibitory effect of samples on THP-1 proliferation in vitro from different companies was different to some extent. In conclusion, the optimized quality standard is more suitable for the detection of Cervus and Cucumis polypeptide injection, and can lay the foundation for improving the safety of multi-component biochemical drugs.
ABSTRACT
Objective To establish a simple and feasible method in analyzing the molecular weight distribution of peptides in thymosin.Methods Improved Tricine-SDS-PAGE electrophoresis was applied to detect the molecular weight of peptides and the content of thymosinα1 in thymosin.Results Tested the thymosin preparations on the domestic market using this im-proved method.It was demonstrated that the peptide molecular weight distribution in thymosin preparations was between 3.5~8.5 kD,also could detect the concentration of 1 μg thymosinα1 in thymosin by using this improved method.Conclusion This improved method is suitable for the analysis of peptides molecular weight distribution and the concentration of thy-mosinα1,so it can be used for control quality of thymosin preparations.
ABSTRACT
Objective:To develop an indirect enzyme-linked immunosorbent assay (ELISA) for semi-quantification of major allergen parvalbumin in fish.Methods:The soluble proteins were prepared from both white and dark muscles of seven species of freshwater fish and five species of marine fish.Tricine-SDS-PAGE and Western blot were performed to examine the protein patterns of fish muscle extracts.Natural parvalbumin being used to make calibration curve was purified from silver carp (Hypophthalmichthy molitrix) by ammonium sulphate fractionation,followed by ion exchange and gel filtration chromatography.The molecular mass of purified protein was estimated by Tricine-SDS-PAGE and identified by Western blot with anti-frog parvalbumin monoclonal antibody PARV-19.ELISA using PARV-19 was carried out to evaluate parvalbumin contents in white and dark muscles.Results:Tricine-SDS-PAGE revealed species-specific differences in proteins of heated extracts.Western blot confirmed that the major bands were showed in Tricine-SDS-PAGE with the molecular masses of 10-14 kD corresponded to parvalbumins recognized by PARV-19 and various numbers of isoforms of parvalbumin existed in different species of fish.There might be some differences in the parvalbumin contents and the epitope region was recognized by PARV-19 based on the differences in relative intensities of protein immunodetection.The ELISA showed that the contents of parvalbumin were 4 to 33 folds higher in the white muscle than in the dark muscle and varied greatly in different species of fish.Conclusion:These results validate that the dark muscle might be less allergenic than the white muscle due to the lower content of parvalbumins,and it is suggested that the commercial anti-parvalbumin antibody PARV-19 can be used to detect parvalbumins from the commercially important species of fish tested in this study and the method we develope succeeds to detect the major allergen in various species of fish.