*4.1. Reagents*

Glutathione assay kit (catalog number: CS0260), xanthine oxidase assay kit (catalog number: MAK078), superoxide dismutase assay kit (catalog number: 19160), antioxidant assay status kit (catalog number: CS0790), malondialdehyde assay kit (catalog number: MAK085), rat interleukin-6 assay kit (catalog number: RAB0333). All the commercial assay kits used were purchased from Sigma Aldrich (St. Louis, MO, USA)

#### *4.2. Plant Extraction and Isolation of the Lanosteryl Triterpene (RA-3)*

Plant extract was prepared from stem bark of *P. longifolia* collected from KwaHlabisa, KwaZulu-Natal, South Africa. The plant material (voucher specimen number RA01UZ) was identified

and confirmed by Dr. NR Ntuli from Botany Department, University of Zululand. The targeted compound (RA-3) was routinely isolated and purified from the chloroform extract using the method well established in our laboratory [18]. The lanosteryl triterpene was isolated over silica gel chromatography and the pure compound was recrystallized in 100% ethyl acetate. Melting point and spectroscopic data analysis were used, in comparison with literature data [14,18], to confirm chemical structure of the isolated pure (>95%) lanosteryl triterpene.
