The influence of the microwave oven on the production of solid culture medium and quality of microbial growth

Abstract

Numerous cultivation media currently exist, whether selective, non-selective, enrichment or identifi cation. However, they all have a common goal, which is the growth of microorganisms; the constitution and quality of the culture medium must favor it. For this reason, an important factor that directly affects the quality of a culture medium is its production. Thus, this article investigated the use of a microwave oven in the production of Sabouraud dextrose agar (SDA), and the microbial inactivation compared to the autoclave in a microbiology laboratory. The quality of the medium, time exposure, and sterilization potential were performed using fungal strains of Candida spp., Cryptococcus spp., Microsporum spp., and Aspergillus spp. The results showed that the advantages of the use of a microwave oven for the preparation of SDA are practicality, speed, lower energy expense, pH, and constituents preservation of the culture medium, resulting in a richer growth compared to autoclaved SDA. The multivariate analysis of digital images allowed the detection of melanoidins (brownish tone of medium), which are responsible for the negative infl uence on the microorganisms growth. This research shows the use of the microwave oven as an effi cient alternative for the production of the culture medium and maintaining their best quality.