A DGGE Marker-Mediated Fast Monitoring of Bacterial Diversity and Comprehensive Identification of High-Temperature Daqu Starter.

UNLABELLED: Bacteria play an essential role in Daqu starter (Daqu) fermentation. The identification of Daqu bacteria was investigated by polymerase chain reaction (PCR) based denaturing gradient gel electrophoresis (DGGE) analysis of the highly variable V3 region of the 16S rRNA gene. Here, we define a novel DGGE marker for the quick identification of Daqu bacteria. A dynamic alteration of the bacterial populations at different stages of fermentation was determined through a 2-y continuous monitoring. The physicochemical parameters of Daqu at different fermentation stages were investigated by weighing, NaOH titration, and HCl hydrolysis together with Fehling reagent methods. Furthermore, infrared spectral analysis using Fourier Transformed Infrared Spectroscopy was performed to determine physicochemical changes of Daqu. Therefore, our studies provide key insight for a comprehensive quality control of Daqu at different fermentation stages using the PCR-DGGE analysis combined with the physicochemical measurement. PRACTICAL APPLICATION: Chinese liquor is one of the 6 well-known distilled spirits in the world. High-temperature Daqu acts as an important source of nutrients and of microorganisms in the solid-state fermentation of Chinese Moutai-flavor liquor, which has a critical impact on the final flavor of the liquor. The study identifies a novel DGGE marker and provides an efficient way to identify bacterial diversity in Daqu from different fermentation stages. Importantly, the study defines dynamic changes of the physicochemical parameters and the infrared spectra analysis of Daqu during the fermentation process. These studies will help to (1) establish a standard operation procedure for Daqu production; (2) stabilize manufacturing process for Daqu fermentation and even for liquor brewing.

[Distribution characteristics of ApoB3'VNTR and hyperlipemia correlation factors in civil aircrew].

OBJECTIVE: To study the frequency distribution in polymorphism of the apoprotein B 3' variable number tandem repeat (ApoB3'VNTR) and influence factors on hyperlipemia in civil aircrew. METHODS: ApoB genotypes were determined by PCR technology and agarose gel electrophoresis. The blood lipids were measured by routine kits. Personal information of flight personnel was collected by questionnaire. RESULTS: Prevalence of the total dyslipidemia (49.5%) and overweight (55.6%) of flight personnel were much higher than that of domestic general population (29.2% and 49.1%) respectively (P < 0.05). There were 16 alleles and 54 kinds of genotypes of ApoB3'VNTR in the 682 flight personnel. The frequency distribution of alleles and genotypes of aircrew in the two air companies had same trend, which was different from the general population. The frequency of the homozygote was 76.54%, which was much higher than that of the other peoples home and abroad (21.50%). The frequency of the big allele (VNTR > or =39) in hyperlipemia groups were higher than that of normal groups. By analysis of co-variance, the body mass index (BMI), low density lipoprotein (LDL) and the total cholesterol(TC) increased with the cumulate flight hours (P < 0.05). In multivariate logistic regression analysis, the BMI was the only factor influencing blood lipids, and the cumulate flight hours was only factors affecting the BMI. Taking the cumulate flight hours logarithm as the independent variable(X), and the BMI as dependent variable(Y), the linearity equations was: Y = 2.730X + 13.584 (R2 = 0.159, P < 0.01). CONCLUSION: There are perhaps special genetic characteristics in the polymorphism of the ApoB3'VNTR in the aircrew. The big allele is correlated with the hyperlipemia. The flight burden not only directly affects the BMI and blood lipids levels, but also it can indirectly affect the lipids levels by BMI.