This application provides a
solid culture medium for the isolation and purification of thermophilic
acidophilic bacteria, its preparation method, and its application. The
solid culture medium is prepared by mixing a
nutrient composition, a coagulant, and deionized water. The coagulant accounts for 9% to 50% of the
solid culture medium by
mass. The coagulant is a high-acyl
gellan gum, containing 3 to 4 acyl groups. The concentration of the high-acyl
gellan gum is 5 g / L to 30 g / L. This solid culture medium is made using high-acyl
gellan gum. By adjusting the
mass percentage of the high-acyl gellan gum, especially by limiting its concentration, the solid culture medium can remain stable for a long time under high temperature and high acid conditions, maintaining good gelation properties. This provides a stable high-temperature and high-acid growth environment for thermophilic
acidophilic bacteria, thus facilitating the successful isolation and purification of these
bacteria. Furthermore, high-acyl gellan gum is widely available and inexpensive, further reducing culture costs.