Bryonolic Acid: A Large-Scale Isolation and Evaluation of Heme Oxygenase 1 Expression in Activated Macrophages

Abstract

Bryonolic acid (BA) is a triterpenoid found in the Cucurbitaceae family of plants. Our interests in the immunomodulatory effects of this class of natural products led us to discover that BA induces a marked increase in the expression of a phase 2 response enzyme, heme oxygenase 1 (HO-1), in a dose-dependent manner. This phenotype has translational implications in malarial disease progression, and consequently we developed a large-scale isolation method for BA that will enable future in vitro and in vivo analyses. We have determined ideal growth conditions and time scale for maximizing BA content in the roots of Cucurbita pepo and analyzed BA production by HPLC. Large-scale extraction yielded 1.34% BA based on dry weight, allowing for the isolation of BA on a multigram scale.