OBJECTIVE: To develop a method for the determination of the titer of azithromycin. METHODS: Turbidimetric method was adopted to determine azithromycin and which was compared with cup-plate method. RESULTS: The linear range of azithromycin was 0.4～2.0IU?mL-1(r=0.999 1), with its recovery rate at 99.70%～100.02%(RSD=0.22%～0.46%), the determination results of 2 kinds of methods was no significant difference. CONCLUSION: Turbidimetric method was proved to be more rapid and convenient than the cup-plate method.

OBJECTIVE:To establish a method for determination of the related substances in Sertaconazole nitrate vaginal tab-let. METHODS: HPLC was performed on the column of Hypersil BDS C18(150 mm×4.6 mm,5 μm)with mobile phase of 0.5%Ammomium acetate solution-acetonitrile-methanol(15∶42.5∶42.5,V/V/V) at a flow rate of 1.0 ml/min,detection wavelength was 220 nm,column temperature was 25℃,and the injection volume was 20μl. RESULTS:The related substances in Sertaconazole ni-trate vaginal tablet can be well separated;the liner range of sertaconazole nitrate was 12.24-28.56 μg/ml (r=0.999 9);RSDs of precision,stability and reproducibility tests were lower than 1%;recovery was 99.38%-99.80%(RSD=0.14%,n=9). CONCLU-SIONS:The method is accurate and reliable with high sensitivity and strong specificity,and can be used for the related substances in Sertaconazole nitrate vaginal tablet.

Objective: To demonstrate the effects of symbiotic bacteria from lettuce on inactivation of norovirus（NV）. Methods: Symbiotic bacteria were isolated from the lettuces sampled from farmlands and supermarkets. NV mixed with symbiotic bacteria was set as the experimental group,without symbiotic bacteria as the control group. After the inactivation by high temperature,ultraviolet light（UV）and chlorine dioxide,the ratio of NV amount in the experimental group and the control group was calculated to evaluate the effects of symbiotic bacteria. The mechanism of symbiotic bacteria was revealed by detecting their effects on the protection of viral capsid protein from UV and on the adsorption of NV. Results: Eleven symbiotic bacteria were identified from lettuces,all of which were bacilli,mainly Pseudomonas. Ten symbiotic bacteria could improve the heat-resistant ability of NV,with Microbacterium oryzae,Cupriavidus taiwanensis（SC061204）,Pseudomonas furukawaii,Enterobacter tabaci and Pseudomonas resinovorans（SC061211）more significant. Eleven symbiotic bacteria could improve anti-UV ability of NV,with Pseudomonas putida,Microbacterium oryzae and Enterobacter tabaci more significant. Only one strain of Pseudomonas putida could improve anti-chlorine dioxide ability of NV（Class I hazard）. Pseudomonas putida,Microbacterium oryzae and Enterobacter tabaci could significantly reduce the damage of NV capsid protein. Nine symbiotic bacteria could promote NV adsorption into lettuces,with the promotion rates ranged from 1.04% to 46.73%;while Pseudomonas putida and Pseudomonas resinovorans（SC061211） could restrain NV absorption,with the promotion rates of -6.50% and -19.85%. Conclusion Symbiotic bacteria from lettuce may enhance the anti-inactivation of NV by protecting capsid protein and promoting adsorption of NV. It is recommended to control the presence of symbiotic bacteria in the process of inactivating NV.

OBJECTIVE: To establish an amino acid assay for the determination of β-lactoglobulin in Anti-HPV biological protein dressing. METHODS: Under acidic conditions, β-lactoglobulin is hydrolyzed into free amino acids, separated by cation exchange chromatography, and derivatived after ninhydrin column. The chromatogram at 570 nm is collected. The content of β-lactoglobulin in the sample is indirectly determined by measuring the lysine content obtained by hydrolysis. RESULTS: β-lactoglobulin has a good linear relationship in the concentration range of 77.28~309.12 μg/mL ( CONCLUSIONS The method is simple, specific, accurate and reproducible, which is suitable for the quantitative analysis of β-lactoglobulin in anti-HPV biological protein dressing.
Amino Acids ; Bandages ; Lactoglobulins