Studies on Community Diversity of Spore-Forming bacteria at Soil of Swamping Wetland in WuLiangSuHai

2014 ◽  
Vol 955-959 ◽  
pp. 3548-3551
Author(s):  
Yu Qin Shao ◽  
Ji Zhao ◽  
Wei Wei Cao ◽  
Jia Yin Lu ◽  
Jing Yu Li

This study used plate count method to analyze the composition of the Spore-forming bacteria community in the soil in swamping wetland, alkaline land, and desert belt, all of which grow in the upstream, midstream and downstream of swamping wetland of Wuliangsuhai. In this process, the Shannon-Wiener index, Simpson index were used to analyze the index of diversity (H), the index of evenness (J), the index of richness (R) and the index of dominance (D) of the Spore-forming bacteria community. The results showed that: the diversity index of in soil of the swamping wetland and desert belt was the highest in the midstream, second in the upstream, and lowest in the downstream; that in soil of the alkaline land was the highest in the midstream, second in the downstream and lowest in the upstream, and showed significant differences between in the midstream and downstream and in upstream; that in soil of the desert belt showed significant differences between in the upstream and downstream and in midstream; in the same area, in the desert belt soil of Spore-forming bacteria more than swamping wetland and alkaline land.

1992 ◽  
Vol 59 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Sarah A. Langford ◽  
Rohan G. Kroll

The keeping quality of properly refrigerated pasteurized milk and cream is primarily determined by post-pasteurization contamination by Gram-negative psychrotrophic bacteria (Phillips et al. 1981; Schröder et al. 1982). Reliable and rapid methods of assessing the levels of contamination by these organisms are therefore of commercial interest.


1942 ◽  
Vol 20c (9) ◽  
pp. 444-456 ◽  
Author(s):  
Norman James ◽  
Marjorie L. Sutherland

Data on the errors of the plate count method are presented. They are based on changes in numbers of bacteria during the crop season in plots supporting different crops. Duplicate samples were used at each step in the procedure. This provides information on variations associated with sampling, which contribute to the error of the plot estimate on any date.A large portion of the differences among estimates from each plot made on different dates is explained by correlations among numbers of bacteria and changes in environmental factors. Obviously, a large error masks a small relationship.This may be minimized by (1) careful sampling and the use of duplicates at each step in the procedure and (2) collecting data for correlating bacteria with changes in many environmental factors other than the one of chief interest m the investigation.


1987 ◽  
Vol 50 (8) ◽  
pp. 665-668 ◽  
Author(s):  
F. F. J. NIEUWENHOF ◽  
J. D. HOOLWERF

An improved impedance method is described with a good standard deviation of repeatability (sm = 0.05 log unit) and a fair standard deviation of the estimate of the plate count from the detection time [(sy)x = 0.33 log unit]. Compared with the standard deviation of repeatability of the plate count method (0.07 log unit), the standard deviation of repeatability of the impedance method described is a significant improvement. The impedimetric experiments were done with a Bactometer M123. The detection times as measured by this instrument were compared with the plate counts at 30°C for samples of raw refrigerated farm milk. With this technique a good indication of the microbiological quality of raw milk can be obtained within 15 h.


2018 ◽  
Vol 24 (2) ◽  
Author(s):  
Zhe Li

In this paper, the application of ATP fluorescence in the detection of colonies in the health environment of hospitals was studied. Firstly, the principle of ATP bioluminescence method was described. Then, ATP bioluminescence and plate count method were used to test the density of the surface of the objects in selected area, taking the time points 2 hours after disinfection as the time nodes. The results showed that the difference between the qualified rate of ATP bioluminescence assay and the plate count method was statistically significant {P<0.01}. Therefore, ATP bioluminescence method was highly correlated with bacterial culture method. The correlation coefficient of pass rate of the two methods was 0.782, which indicated that there was a positive correlation between the two test results. Besides, the detection results showed that ATP bioluminescence method had higher sensitivity than plate counting method. Therefore, ATP bioluminescence method was more suitable for the rapid detection of the colony of hospital health environment, and helps the hospital to better manage its environmental hygiene conditions. 


2000 ◽  
Vol 66 (1) ◽  
pp. 453-454 ◽  
Author(s):  
R. Wayne Jackson ◽  
Karen Osborne ◽  
Gary Barnes ◽  
Carol Jolliff ◽  
Dianna Zamani ◽  
...  

ABSTRACT A new SimPlate heterotrophic plate count (HPC) method (IDEXX Laboratories, Westbrook, Maine) was compared with the pour plate method at 35°C for 48 h. Six laboratories tested a total of 632 water samples. The SimPlate HPC method was found to be equivalent to the pour plate method by regression analysis (r = 0.95;y = 0.99X + 0.06).


2015 ◽  
Vol 81 (21) ◽  
pp. 7443-7447
Author(s):  
Rosa M. Lopez-Gigosos ◽  
Alberto Mariscal ◽  
Eloisa Mariscal-Lopez ◽  
Mario Gutierrez-Bedmar ◽  
Joaquin Fernandez

ABSTRACTWe developed a fluorescent β-d-glucuronidase activity (BGA)-based assay for detecting and quantifyingEscherichia coliin samples to assess the biocide efficacy of hand antiseptics. The fluorescence level is proportional to the number of viableE. coliorganisms present. We compared our assay results to those of theE. coliplate count method specified by the European standard for testing hygienic hand rub disinfectant products (EN1500). The plate count method requires excessive handling and materials and is not valid if the number of organisms per plate is too low or high for counting in many of the samples. We optimized the fluorescent assay based on the cleavage of 4-methylumbelliferyl-β-d-glucuronide by adding 4-nitrophenyl-β-d-glucuronide, a nonfluorogenic BGA substrate, to induce glucuronidase activity and reduce assay time. Furthermore, our method can be automated and eliminates the need for multiple dilutions. Fluorescence was temporally monitored, and the time required to reach a specific value of fluorescence was correlated with the initial number of viableE. coliorganisms on the samples. There was a positive correlation (P< 0.05) with a high correlation coefficient (R2= 0.82) between theE. colicounts by plate count and fluorescence methods. Reported effects in fluorescent BGA were compared to the EN1500 plate count method with five hand disinfectants. We found our method more advantageous, because it was as sensitive as the EN1500 method, requires less time to complete, and is less expensive and less laborious than conventional plating techniques.


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