80 samples of street-food (40 samples of raw vegetable, 40 samples of cooked food) were examined at 4 places of crowed eating in Hue city. The infection of aerobic bacterium, total coliform, faecal coliform all were at very high concentration, highly-polluted level. 6 species of S.aureus and 3 species of NAG were isolated, 62.5% samples of cooked food and 100% samples of raw food were did not meet the sanitary standards, which leads to high risks of food poisoning due to infection
Hygiene ; Microbiological Techniques

Humans ; Infant, Newborn ; Microbiological Techniques ; Sepsis ; blood ; microbiology

Bacteria ; chemistry ; Microbial Sensitivity Tests ; Microbiological Techniques ; Reagent Kits, Diagnostic

Child ; Clinical Laboratory Techniques ; Humans ; Microbiological Techniques ; Viral Load ; Virus Cultivation ; Virus Diseases ; diagnosis

Co-culture systems consisted of photosynthetic microorganisms and others heterotrophic microbes have attracted great attention in recent years. These systems show many advantages when compared with single culture grown under autotrophic conditions, such as less vulnerable to pollution and more stability, thus have been applied to wastewater treatment, soil remediation, biodegradable harmful substances, and production of high value-added products. In order to explore basic theory and further applications, we summarize here recent progresses in artificial co-culture systems of using photosynthetic microorganisms, to provide a current scientific understanding for the rational design of the co-culture system based on photosynthetic microorganisms using synthetic biology.
Coculture Techniques ; Heterotrophic Processes ; Microbiological Techniques ; trends ; Microbiota ; physiology ; Photosynthesis ; physiology ; Synthetic Biology ; trends

BACKGROUND: In most clinical microbiology laboratories, inoculation of specimens on plates is performed manually and is a time-consuming process. The efficiency of this process can be improved by using an automated instrument. Currently, several automated instruments have been introduced for inoculation of samples. In this study, we have evaluated an automated instrument, PREVI Isola(R) (Biomerieux, France), used for inoculation of body fluids and urine specimens. METHODS: Both manual and automated instrument methods were used to inoculate 74 body fluid and 204 urine samples. Precision was evaluated by testing 3 types of urine samples (A, 6x10(3) colony-forming units (CFU)/mL; B, 3x10(4) CFU/mL; and C, >10(6) CFU/mL) in replicates of 20. Results of the 2 methods were compared by counting the isolated colonies on agar plates after incubation. The time required for both methods was also compared. RESULTS: The coefficient of variation (CV) of samples A, B, and C examined using the automated instrument method was 176.1%, 18.1%, and 12.6%, respectively. The sensitivity and specificity of testing body fluid samples were 77% and 100%, respectively, and those of urine samples were 87% each. The time required for testing 15 body fluid specimens and that for inoculation of each specimen was 9.7 min shorter using PREVI Isola(R) than using the manual method. CONCLUSIONS: The results of body fluid and urine culture by inoculation using the automated instrument, PREVI Isola(R), showed relative good agreement with those obtained using the manual method. The use of PREVI Isola(R) would be expected to reduce the time and labor involved in inoculating various kinds of specimens.
Agar ; Automation, Laboratory ; Body Fluids ; Microbiological Techniques ; Sensitivity and Specificity ; Stem Cells

OBJECTIVE7 variable but nonculturable-state strains of Enterotoxigenic Escherichia coli (ETEC) during the routine bacterial subculture were found in our lab and their morphology and antigen studied. Biological features, antigens and pathogenicity of the revertants were also tested and compared to that of the initial strains in order to detect their variations.

METHODSBiological variations between the variable but nonculturable-state and the revertant of every strain were detected, using the routine gram-staining, reverting the isolates in animal intestinal, reverting their pathogenicity, serological agglutination, biochemical identifications and antibiotic resistance tests.

RESULTSFor the 7 variable but nonculturable-state strains of ETEC,other than the trains that had changed into sphero vegetale cells, there were no other obvious variations found. However, high pathogenicity of these strains still remained.

CONCLUSIONThe presence of variable but nonculturable-state strains suggested that the routine method of bacteria storage should be changed and more attention should be paid to realize the existence of this kind of bacteria during the routine surveillance of the communicable diseases.

Heparinase II (Hep II) from Flavobacterium heparinum is an enzyme that could specifically cleave certain sequence of heparin and heparan sulfate. In this work, fermentation conditions of recombinant heparinase II (His-Hep II) producing bacteria were optimized, including initial induction time, inducer (IPTG) concentration, induction temperature and induction time. The optimum conditions were as follows: cultivating recombinant bacteria to exponential prophase under 37 degrees C, then adding IPTG to a final concentration of 0.3 g/L, finally cultivating recombinant bacteria under 20 degrees C for 10 h. The total crude enzyme activity reached 570 U/L. Based on these results, high cell density fermentation of recombinant bacteria was studied. The final OD600 could reach 98 and the total crude enzyme activity of His-Hep II increased to 9 436 U/L.
Fermentation ; Flavobacterium ; metabolism ; Microbiological Techniques ; Polysaccharide-Lyases ; biosynthesis ; Recombinant Proteins ; biosynthesis

Anthrax ; diagnosis ; prevention & control ; therapy ; Bacillus anthracis ; growth & development ; Humans ; Microbiological Techniques

OBJECTIVEThis research was to establish a method for fast identification of mycobacteria in microtiter liquid culture and to evaluate its clinical value.

METHODS2-thiophenecarboxylic acid hydrazide (TCH) and paranitrobenzoic acid (PNB) at different concentrations were added into liquid culture in 96-well plate. Different mycobacterium standard strains were incubated in liquid culture with PNB and TCH for 7 to 10 days. According to the growth assay for 15 mycobacterium strains and 30 mycobacterium tuberculosis strains, the best PNB and TCH concentration were determined. A total of 424 clinical mycobacterium isolates were identified by microtiter liquid culture at the best PNB and TCH concentration. The results of microtiter liquid culture were compared with those of PCR and DNA sequencing.

RESULTSThe best concentration of PNB was 200 µg/ml in microtiter liquid culture. Compared with the results of PCR, the sensitivity and specificity for identification of mycobacterium tuberculosis complex in microtiter liquid culture were 97.8% (306/313) and 100.0% (107/107) respectively and those for non-tuberculosis mycobacteria in microtiter liquid culture were 100.0% (107/107) and 96.5% (306/317) respectively. The best concentration of TCH was 0.5 µg/ml. Compared with the results of PCR, the sensitivity of mycobacterium tuberculosis in microtiter liquid culture was 100.0% (305/305). The specificity remained under and more studies were needed.

CONCLUSIONIn microtiter liquid culture with PNB and TCH, mycobacteria can be identified in 7 to 10 days. The results were accurate and the process was simple without expensive equipments. This method meets clinical needs and can be used in all level hospitals in China.