Abstract: Objective To observe malate dehydrogenase and alkaline phophatase patterns of ten isolates of Blastocystis hominis （Bh） from Guangxi. Methods Blastocystis hominis agents were isolated from the fecal specimens of patients and cultivated in vitro. The samples were prepared for polyacrylamide gel slab electrophoresis（PAGSE）. Sodium malate and 1-Naphthyl phosphoric acid sodium were used as substrates. NBT and fast blue RR salt were used to stain MDH and ALP respectively. The isoenzyme bands were recorded with relative mobility（Rm）. Results Among the 10 isolates, 7 MDH bands were found, more with Rm34， Rm47， Rm51， Rm55，and Rm59. All the isolates showed Rm34 and Rm51 bands. 5 bands showed ALP patterns: Rm22， Rm25， Rm28， Rm35，and Rm38. Difference existed with the MDH and ALP patterns among the isolates. Conclusion MDH and ALP patterns may indicate a genetic difference among the isolates, which might play a role in its classification.

Key words: Blastocystis hominis, Isoenzyme, Electrophoresis