The College of Biotechnology at Al-Qasim Green University discussed a master's thesis on new method for preventing tooth decay using a bacterial nitrate-reducing enzyme by the postgraduate student, Ms  Athraa Kadhim Jawad.

The thesis aimed at isolating and identifying beneficial nitrate-reducing bacteria naturally found in the mouth and extract the nitrate-reducing enzyme from them, as well as evaluating its efficacy and potential use in developing oral and dental care products.

The thesis included isolating and identifying the bacteria using PCR and 16S rRNA analysis techniques, enzyme was then extracted and purified using advanced techniques, culminating in Preparative HPLC (Preparative Liquid Chromatography), as well as testing on samples of normal and decayed teeth, and its results were compared with those of conventional toothpaste.

The study reviewed that Actinomyces bacteria were the most efficient in producing the enzyme, furthermore, tests confirmed its properties were compatible with the natural oral environment, practical experiments also demonstrated the enzyme's ability to improve the appearance of decayed teeth and enhance their protection, with results approaching those of toothpaste and this opens the door for its future use in the manufacture of toothpastes and mouthwashes to reduce tooth decay.

Media and Government Communication Directorate 

Ministry of Higher Education and Scientific Research

July 5, 2026