During the initial experiments, we observed that
methanolic extract of P. longum fruits possessed
mosquito larvicidal activity against Cx. p. pallens,
and also only I mgAiter of hexane fraction had a
strong larvicidal activity of IOOVo mortality. Moderate
activity and little activity were produced from
other organic solvent fractions. No activity was observed
in the water fraction. One active isolate from
the hexane fraction showed potent larvicidal activity,
shown in Table 1, and it was characterizedby
the spectral analyses as pipernonaline (Fig. l).