Search results
Results from the WOW.Com Content Network
Bacterial growth curve\Kinetic Curve. In autecological studies, the growth of bacteria (or other microorganisms, as protozoa, microalgae or yeasts) in batch culture can be modeled with four different phases: lag phase (A), log phase or exponential phase (B), stationary phase (C), and death phase (D). [3]
Figure 1: A bi-phasic bacterial growth curve.. A growth curve is an empirical model of the evolution of a quantity over time. Growth curves are widely used in biology for quantities such as population size or biomass (in population ecology and demography, for population growth analysis), individual body height or biomass (in physiology, for growth analysis of individuals).
Under certain conditions, it may result in preferential growth of resistant bacteria, while growth of susceptible bacteria is inhibited by the drug. [84] For example, antibacterial selection for strains having previously acquired antibacterial-resistance genes was demonstrated in 1943 by the Luria–Delbrück experiment. [85]
The sample with the initial unknown bacterial concentration (C 0) is placed at a temperature favoring bacterial growth (in the range 37 to 42 °C if mesophilic microbial population is the target) and the electrical parameters R s and C s are measured at regular time intervals of few minutes by means of a couple of electrodes in direct contact ...
A secondary metabolite is typically present in a taxonomically restricted set of organisms or cells (plants, fungi, bacteria, etc.). Some common examples of secondary metabolites include: ergot alkaloids, antibiotics, naphthalenes, nucleosides, phenazines, quinolines, terpenoids, peptides and growth factors.
The Monod equation is a mathematical model for the growth of microorganisms. It is named for Jacques Monod (1910–1976, a French biochemist, Nobel Prize in Physiology or Medicine in 1965), who proposed using an equation of this form to relate microbial growth rates in an aqueous environment to the concentration of a limiting nutrient.
The composition of Mueller Hinton agar can affect the growth characteristics of bacterial isolates, as well as their response to antibiotics. For example, variations in the pH of the medium can affect the activity of certain antibiotics, and the presence of certain nutrients can promote the growth of specific bacterial species.
The minimum inhibitory concentration, which is the lowest concentration of the antibiotic that stops the growth of bacteria, can be estimated from the size of the zone of inhibition. Antibiotic susceptibility testing has been needed since the discovery of the beta-lactam antibiotic penicillin. Initial methods were phenotypic, and involved ...