What method is primarily used to culture Mycoplasma hominis from genital specimens?

The primary method used to culture Mycoplasma hominis from genital specimens is through the use of 'M' agar, which contains arginine and phenol red. Mycoplasma species, particularly Mycoplasma hominis, are unique in that they lack a cell wall, which makes them difficult to culture using standard media. 'M' agar is specifically designed to support the growth of Mycoplasma by providing a suitable environment that includes nutrients like arginine, which serves as a carbon source, and phenol red, a pH indicator that helps in identifying microbial growth based on color changes.

The presence of phenol red in the agar allows for the visualization of metabolic activity, as the pH can shift due to the byproducts of the bacteria’s metabolism, thus indicating the successful growth of Mycoplasma. This selective culturing method is crucial for isolating Mycoplasma hominis, as it caters to the specific nutritional and environmental needs of these fastidious organisms, facilitating their identification and study.

Other media listed, such as 'U' agar, are tailored for different Mycoplasma species or for other testing purposes, which may not be suitable for the growth of Mycoplasma hominis specifically