2.3. Equipment The HPLC system was a Hitachi Elite LaChrom chromatogra pher (Tokyo, Japan) equipped with an L-2420 UV-Vis detecto an L 2300 column oven, an L 2200 autosampler, and an L-2130 pump. Ezohtorn Elite 332 SP2 software (Agi ent Technolo. gies, CA, USA was used for data acquisition