| || || Kava (Beverage) -- Analysis|
| || || Potential application of Kava (Piper methysticum F. ) in nematode control|
Author: Singh, Ranjeeta D.
Institution: University of the South Pacific.
Subject: Kava (Beverage) -- Fiji, Kava (Beverage) -- Analysis
Call No.: Pac QK 495 .P67 S56 2006
Copyright:This thesis may NOT be copied without the authors written permission.
Abstract: Kava (Piper methysticum) has long history of its use in social and ceremonial gatherings and for medicinal purposes by the Pacific islanders. Research has identified the active ingredients as the kava lactones, which have been widely tested for various bioactivity properties. The water soluble compounds on the other hand have not been scientifically explored much. Work presented in this thesis reports for the first time the nematicidal property of polar extracts of dried kava roots. The water soluble compounds of dried kava root material referred to as sample X and the highly polar extract, sample Y (sample X less the ethanol solubles) has been tested for juvenile mortality and suppression of egg hatching. Samples Y1, Y2, Y3 and Y4 obtained by semi preparative HPLC separation of sample Y, were tested for juvenile mortality only. The results of these experiments were compared with the activity of gallic acid as the standard. Efficacy of kava powder was tested in pot experiments as soil amendment. Samples X, Y, Y1, Y2, Y3, and Y4 showed significant activity towards juvenile mortality and suppression of egg hatching. Samples X of FJ and VA kava showed some differences in activity towards juvenile mortality but similar activity was noted for egg hatching experiments for both FJ and VA kava samples. H-NMR analyses of the four fractions isolated have shown the possibility of the presence of glucoside like compounds in the polar extract of kava. Kava powder when mixed with soil significantly decreased the root Potential Application of Kava (Piper methysticum F.) in Nematode Control galls on tomato plants. Allowing kava to degrade in the soil before planting seedlings minimized the phytotoxic effect while being effective in controlling nematodes. These results have indicated that kava does have the nematicidal polar compounds. Further purification of the extracts obtained will lead to the isolation of individual compounds. GC-MS and NMR analysis of individual compounds will further provide information on the structure of these compounds.