Isolation of adenosine, iso-sinensetin and dimethylguanosine with antioxidant and HIV-1 protease inhibiting activities from fruiting bodies of Cordyceps militaris

According to previous studies, a close relationship between oxidative stress and AIDS suggests that antioxidants might play an important role in the treatment of AIDS. Cordyceps militaris was selected from nine edible mushrooms by assay of inhibition of erythrocyte hemolysis. Macroporous adsorption resin and HPLC were used to purify three micromolecular compounds named L3a, L3b and L3c. L3a was identified to be adenosine with the molecular formula C10H13N5O4; L3b was 6,7,2′,4′,5′-pentamethoxyflavone with the molecular formula C20H20O7, and L3c was dimethylguanosine with the molecular formula C12H17N5O5. The compound 6,7,2′,4′,5′-pentamethoxyflavone was first isolated from C. militaris. The assay of inhibition of HIV-1 protease (HIV-1 PR) was based on the fact that the expression of this enzyme can inhibit the growth of E. coli. This is a new screening system for HIV-1 PR inhibitors. Both L3a and L3b showed high inhibition to HIV-1 PR. These compounds could be new anti-HIV-1 PR drugs.