Estimation of the density of organisms using a serial dilution experiment

2007 ◽  
Vol 1 (1) ◽  
pp. 43-56
Author(s):  
Milton W. Loyer
Keyword(s):  
Serial Dilution ◽  
Dilution Experiment

scholarly journals Testing Deviation for a Set of Serial Dilution Most Probable Numbers from a Poisson-Binomial Model

2006 ◽  
Vol 89 (1) ◽  
pp. 166-171
Author(s):  
Robert J Blodgett
Keyword(s):  
Finite Number ◽  
Poisson Distribution ◽  
Serial Dilution ◽  
Binomial Model ◽  
Similar Test ◽  
Dilution Experiment

Abstract A serial dilution experiment estimates the microbial concentration in a broth by inoculating several sets of tubes with various amounts of the broth. The estimation uses the Poisson distribution and the number of tubes in each of these sets that show growth. Several factors, such as interfering microbes, toxins, or disaggregation of adhering microbes, may distort the results of a serial dilution experiment. A mild enough distortion may not raise suspicion with a single outcome. The test introduced here judges whether the entire set of serial dilution outcomes appears unusual. This test forms lists of the possible outcomes. The set of outcomes is declared unusual if any occurrence of an observed outcome is on the first list, or more than one is on the first or second list, etc. A similar test can apply when there are only a finite number of possible outcomes, and each outcome has a calculable probability, and few outcomes have tied probabilities.

Interval Estimation of the Density of Organisms Using a Serial-Dilution Experiment

Biometrics ◽  
1984 ◽  
Vol 40 (4) ◽  
pp. 907 ◽  
Author(s):  
Milton W. Loyer ◽  
Martin A. Hamilton
Keyword(s):  
Interval Estimation ◽  
Serial Dilution ◽  
Dilution Experiment

scholarly journals CFD/RELAP5 Coupling Analysis of the ISP No. 43 Boron Dilution Experiment

2021 ◽  
Author(s):  
Linrong Ye ◽  
Hao Yu ◽  
Mingjun Wang ◽  
Qianglong Wang ◽  
Wenxi Tian ◽  
...  
Keyword(s):  
Coupling Analysis ◽  
Dilution Experiment ◽  
Boron Dilution

scholarly journals STUDIES ON THE BACTERIOPHAGE OF D'HERELLE

1925 ◽  
Vol 42 (4) ◽  
pp. 483-497 ◽  
Author(s):  
Jacques J. Bronfenbrenner ◽  
Charles Korb
Keyword(s):  
Quantitative Evaluation ◽  
Bacterial Species ◽  
Relative Concentration ◽  
Serial Dilution ◽  
The Other ◽  
Resistant Bacteria ◽  
Dilution Method ◽  
High Concentration ◽  
Average Size ◽  
Broth Dilution

The experiments reported above confirm the fact that lytic principle is distributed in active solution in a state of indivisible units. This permits its quantitative evaluation by serial dilution, as well as by plating on agar. The latter method, however, often gives readings considerably lower than those obtained by the broth dilution method of titration. By varying the concentration of agar it has been possible to show that the discrepancy is due to adsorption of the lytic agent on agar. When the concentration of the latter is increased from 0.3 per cent to 2.5 per cent the number of plaques of lysis is reduced more than 100 times. At the same time the average size of the plaques also decreases approximately to one-tenth of the original. The size, as well as the number of plaques, has been found to depend also on the condition of the culture employed in titration. Thus, when the culture exposed to the action of lytic agent is composed of young susceptible bacteria, the greater the concentration of bacteria, the smaller the plaques. When the culture is composed partly of young and partly of old susceptible bacteria, both the size and the number of the plaques are diminished with the increase in the relative concentration of old bacteria. On the other hand, presence in the culture of resistant bacteria does not affect either the size or the number of the plaques so long as the relative concentration of susceptible bacteria in the culture is sufficient to allow formation of them. The plaques appearing in the presence of a high concentration of resistant variants in the culture are relatively indistinct owing to overgrowth. Under carefully controlled conditions the size of plaques is found to be determined by the character of the lytic filtrate. Thus in the case of lytic agents which act upon more than one bacterial species the size of the plaques remains constant, irrespective of the bacterial substratum used for the production of the active filtrate.

Four-parameter paired response curve for serial dilution assays

2021 ◽  
pp. 1-16
Author(s):  
Youyi Fong ◽  
Sallie R. Permar ◽  
Georgia D. Tomaras
Keyword(s):  
Response Curve ◽  
Serial Dilution

scholarly journals ANTIBIOTICS RESISTANCE OF CORYNEBACTERIUM NON DIPHTHERIAE STRAINS

2017 ◽  
pp. 3-8
Author(s):  
G. G. Kharseeva ◽  
N. A. Voronina ◽  
T. D. Gasretova ◽  
O. I. Sylka ◽  
S. Yu. Tyukavkina
Keyword(s):  
Serial Dilution ◽  
Urogenital Tract ◽  
Antibiotics Resistance ◽  
Dilution Method ◽  
Frequency Of Occurrence ◽  
Serial Dilution Method ◽  
Resistant Strains

Aim. Study the frequency of occurrence of antibiotics resistant strains of various species of Corynebacterium non diptheriae. Materials and methods. C.pseudodiphtheriticum, C.pseudotuberculosis, C.xerosis, C.amycolatum, C.striatum, C.ulcerans strains isolated from patients with pathologies of respiratory and urogenital tract, as well as individuals taking prophylaxis examination were used. Sensitivity to antibacterial preparations was determined by the serial dilution method. Results. The highest number of Corynebacterium non diptheriae strains displayed resistance to benzylpenicillin (54.8%) and lincomycin (50.7%), and lowest - to cefotaxime, cefazolin (6.8%) and vancomycin (13.7%). The highest number of antibiotics resistant strains were detected among members of C.pseudotuberculosis {100%), C.xerosis (96.0%) and C. pseudodiphtheriticum (81.0%) species. Polyresistant strains were detected most frequently among C.xerosis, C.amycolatum and C.striatum species. Strains of Corynebacterium non diptheriae most frequently displayed resistance to 1 or 2 antibacterial preparations (24.7%), less frequently - to 3 (20.5%), 4 (13.7%), 5 (4.1%) and 6 (1.4%) preparations. Conclusion. The amount of antibiotics resistant strains of Corynebacterium non diptheriae is large (89.0%) and non-similar in various species.

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