A. Kubatova et al., Comparison of subcritical water and organic solvents for extracting kava lactones from kava root, J CHROMAT A, 923(1-2), 2001, pp. 187-194
Subcritical water extraction of lactones from a kava (Piper methysticum) ro
ot was compared to a Soxhlet extraction with water, to boiling in water, an
d to a sonication in acetone. For ground kava (250-500 mum), 2 h of subcrit
ical water extraction were required for a complete extraction at 100 degree
sC, while at 175 degreesC. 20 min were sufficient. For a complete extractio
n of the unground (shredded) kava, the time of extraction was extended to 4
0 min at 175 degreesC. Boiling for 2 h and extraction with Soxhlet apparatu
s for 6 h. both of which employed water at atmospheric pressure, produced y
ields 40-60% lower than those obtained with subcritical water. With ungroun
d kava, 40 min of subcritical water extraction yielded essentially the same
recoveries of lactones as 18 h of sonication with acetone, methylene chlor
ide, or methanol. (C) 2001 Elsevier Science B.V. All rights reserved.