Agarotetrol in agarwood: its use in evaluation of agarwood quality

Agarwood, which is used as medicine and incense, contains sesquiterpenes and chromones. Agarotetrol is a chromone derivative found in high concentrations in the water-extract fraction of agarwood and thus may be present in pharmaceutical products made from decoctions of agarwood. Agarotetrol has been reported to be present at the early stages of cell death in calli. We therefore examined the presence of agarotetrol in medical- and incense-grade agarwood, in agarwood-source plants lacking resin deposits, and in artificially made agarwood. Agarotetrol appeared as a large peak in the HPLC chromatograms of all samples of medical-grade and artificially made agarwood, and in most incense-grade agarwood samples. In contrast, agarwood samples lacking resin deposits did not contain agarotetrol. These results show that agarotetrol is characteristic of resin formation. Agarotetrol was also detected in decoctions of agarwood. A newly developed TLC method for the detection of agarotetrol in agarwood is described.