Potency of Mangosteen Pericarp Extract to Inhibit 38-kDa and Ag85 Protein Secretion by Mycobacterium tuberculosis H37Rv

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. The α-mangostin in mangosteen pericarp extract can inhibit M. tuberculosis growth. This study examined the potency of α-mangostin in mangosteen pericarp extract to inhibit 38-kDa and Ag85 protein secretion from M. tuberculosis H37Rv. The samples used in this study were divided into three independent variable groups (3.125 µg/ml; 6.25 µg/ml; and 12.5 µg/ml α-mangostin in the mangosteen pericarp extract), a positive control group (rifampin), a negative control group (M. tuberculosis H37Rv), and the Garcia® group (trademark of the mangosteen peel extract capsule). HPLC-MS/MS detected that the mangosteen pericarp extract contained 5,984.55 µg/g α-mangostin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and dot blot analysis were conducted to analyze the profile and specificity of both proteins. This study revealed that 6.25 µg/ml of mangosteen pericarp extract had the greatest potency for inhibiting 38-kDa protein secretion from M. tuberculosis H37Rv, and 12.5 µg/ml mangosteen pericarp extract had greater potency for inhibiting Ag85 protein secretion than did the other doses. Thus, α-mangosteen from mangosteen pericarp extract can inhibit Ag38 and Ag85 secretion.