Figure A1.

RP-HPLC analysis of reconstituted aqueous extract of H. verticillata (I) with comparison to standards: 5 lignan mix (II) [6 mg/mL]; podophyllotoxin (III) [7.8 mM]; (-)-yatein [10 mM] (IV) and 4′-demethylpodophyllotoxin [2 mM] (V). Separations were achieved using a Perkin-Elmer Series 200 chromatograph, Waltham, MA, USA fitted with a Chromsep C18, 250 × 4.6 mm, 5 µm column and C18 guard column. An injection volume of 20 uL was independently run for H. verticillata (I) and each of the standards (II, III, IV and V) for 34 min at a flow rate of 1 mL/min. at wavelength 290 nm at an ambient temperature of 18 °C. The mobile phase consisted of methanol and water using gradient elution: 20% methanol for 2 min increased to 60% linearly over 4 min and held for 2 min. Methanol was further increased to 80% linearly over 9 min and held for 7 min. The column was washed by running 100% methanol for 8 min then decreased to 20% to equilibrate the column for the next injection.