Piperitone

Phytotherapy Research, 2004, 18(11):911-914.

Piperitone from Mentha longifolia var. chorodictya Rech F. reduces the nitrofurantoin resistance of strains of enterobacteriaceae.[Reference: WebLink]

METHODS AND RESULTS:
The diluted essential oil of Mentha longifolia (L.) var. chlorodictya Rech F. foliage enhanced the bactericidal activity of nitrofurantoin decreasing the minimum inhibitory concentration (MIC) of nitrofurantoin for nitrofurantoin-resistant strains of Enterobacteriaceae. Thin-layer chromatography (TLC) analysis of the essential oil detected a fraction (R(f) = 0.35, UV lambda(max) of 232.5), which was the most effective in enhancement of nitrofurantoin activity.
CONCLUSIONS:
Using gas liquid chromatography and known standards, the active fraction was identified as Piperitone. 1 microl of the Piperitone fraction decreased the MIC of nitrofurantoin 3-20 fold for the different strains of Enterobacteriaceae tested.

Fitoterapia, 2006, 77(7):506-510.

Comparative effects of Cymbopogon schoenanthus essential oil and piperitone on Callosobruchus maculatus development.[Reference: WebLink]

METHODS AND RESULTS:
The insecticidal activity of crude essential oil extracted from Cymbopogon schoenanthus and of its main constituent, Piperitone, was assessed on different developmental stages of Callosobruchus maculatus. Piperitone was more toxic to adults with a LC(50) value of 1.6 microl/l vs. 2.7 microl/l obtained with the crude extract.
CONCLUSIONS:
Piperitone inhibited the development of newly laid eggs and of neonate larvae, but was less toxic than the crude extract to individuals developing inside the seeds.