Development of a Competition Model for Streptococcus mutans and Streptococcus sanguis in Mixed Culture: A Mathematical Analysis
Md. Kamrujjaman *
Department of Mathematics, University of Dhaka, Dhaka 1000, Bangladesh
Mohammad Shahnoor Hossain
Department of Genetic Engineering and Biotechnology, University of Dhaka, Dhaka 1000, Bangladesh
*Author to whom correspondence should be addressed.
Abstract
A competitive mathematical model for the growth of Streptococcus mutans and Streptococcus
sanguis is developed in this study. The main goal of this paper is to investigate the roles of
two different growth laws: The logistic growth and the Smith growth to determine the competition
outcome between two organisms in a given micro-ecological domain. We demonstrated that the
competitive exclusion of a food limited bacteria is inevitable based on resource availability of species
following the logistic growth. If the resource utilization capacity is equal then there is a possible
coexistence and both bacteria co-operate with each other. This model can be used as a basic
competition model for the prediction of the outcome of growth between any others microorganisms.
Keywords: Streptococcus mutans, Streptococcus sanguis, competition;, phase portrait, coexistence