The analysis of anthraquinone was
performed either spectrophotometrically by taking
measurement from a spectrophotometer (Perkin
Elmers, Waltham, USA, Model No. Lambda 25)
at 325 nm for comparison of extraction efficiency
between each extraction method and
chromatographically using HPLC (Shimadzu,
Japan) for the determination of anthraquinone
content in root, stem, bark and leaf of Morinda
sp. with Alltima C8 column (Alltech, USA) at
40°C and a mobile phase flow rate of 2 ml/min
whose composition was 32%(v/v) acetonitrile and
0.5%(v/v) acetic acid. The injection volume and
run time were 5 μl and 25 min, respectively.