Data collection and integration were accomplished using Shimadzu Labsolutions software. The wavelength of detection was at 339 nm. Separation of analytes was performed using an Alltech Apollo 4.6 mm × 250 mm, 5-μm RP-C18 column, preceded by a Brownlee pre-column 1.5 cm × 3.2 mm, 7-μm, RP-C18 (Grace Davison Discoveries Sciences Pty Ltd., Epping, VIC, Australia).