This study investigated the use of micelle-mediated extraction (MME) of anthraquinones from the root of Morinda citrifolia and cloud point concentration (CPC) of the extract as effective alternatives for extraction and concentration of the product without using toxic organic solvent. MME were carried out at ambient pressure and temperature using two types of surfactants: Triton X-100 and Genapol X-080 to determine the effect of concentrations on the percent anthraquinones extracted. In addition, micelle-mediated pressurized hot water extraction (MMPHWE) was investigated in a continuous flow system at a constant flow rate of 4 ml/min surfactant solutions at the concentration between I and 5% (v/v). The extract from the most suitable MMPHWE, with 1% Triton X-100 solution at 80 degrees C, was then concentrated using CPC and the effects of surfactant concentration. the incubation time and temperature were determined on the concentration efficiency. For CPC, the most suitable condition was at 75 degrees C and the incubation time was 30 min using Triton X-100 at 1% (v/v) (surfactant/the extract). The extract obtained by MMPHWE followed by CPC was analyzed with HPLC to quantify the amount of the most medicinally important anti-cancer compound, damnacanthal. The result showed that as a result of lower temperature requirement, the compound degradation could be reduced by MMPHWE, compared with pressurized hot water extraction (PHWE) without use of surfactant. In addition, the amount of energy required for extraction and concentration could be greatly reduced. (C) 2008 Elsevier B.V. All rights reserved.