Efficacy of Turmeric, Ginger, Galangal and Fingerroot for Controlling Head Louse Infestation

Abstract

The objective of this study was to test the efficacy of turmeric, ginger, galangal and
fingerroot for the control of head louse infestation. Rhizomes of turmeric (Curcuma
longa L.), ginger (Zingiber officinale Roscoe), galangal (Alpinia galanga (L. Willd.)
and fingerroot (Boesenbergia rotunda (L.) Mansf.) were extracted with 95% ethyl
alcohol. The crude extracts were evaporated by an evaporator From the crude
extracts purified extracts were prepared in five concentrations (10, 15, 20, 25 and
30%) by diluting the extracts in 95% ethyl alcohol. The extracts then were tested
for insecticidal activity against head louse (Pediculus humanus capitis) by contact
bioassay. Twenty replication experiments, each one for 4 times, were performed in
exposing the insects for 8 hours with the extracts. The insecticidal activities of the
extracts were dose dependent. At the highest concentration (30%) of the crude
extracts of A. galangal resulted in a complete eradication of the head lice at 8 hours
post‐exposure with median lethal time (LT50) of about = 3.67 hours, followed by
those of the crude extracts of C. longa, Z. officinale and B. rotunda with 95, 85 and
80% eradication at 8 hours post‐exposure (LT50 = 4.17, 4.68 and 5.20 hours,
respectively). Similarly the highest concentration (30%) of the purified extracts of
A. galangal also eradicated the head lice to 100% after at 8 hours post‐exposure
with a LT50 of about 4.12 hours, followed by those of the purified extracts of C.
longa , Z. officinale and B. rotunda demonstrated with 90, 85 and 80% eradication
at 8 hours post‐exposure (LT50 = 4.74, 5.05 and 5.61 hours, respectively). The
median lethal concentration (LC50) of the crude extract of A. galangal,C. longa, Z.
officinale, B. rotunda were 8.52, 9.74, 15.26 and 14.96 mg/ml, respectively, while
those of the purified extracts of these plants were 11.58, 15.50, 18.45 and 18.37
mg/ml, respectively. There was no statistically significant difference of the
insecticidal activity of the crude extract and the purified extract from each plant.
There was no statistically significant difference of the insecticidal activity among the
four plant species. In conclusion: No statistically significant differences could be
observed for the efficacy of turmeric, ginger, galangal and fingerroot extracts in
controlling head louse infestation.