Sesquiterpenes of Amazonian Piper species*

Essential Oils from Four Piper Species

ÐThe essential oils from Piper capense, P. nigrum, P. guineense and P. umbellatum from S. Tome e Prõ ncipe were investigated for the ®rst time. They were analysed by GC, GC-mass spectrometry and C NMR. Monoterpene hydrocarbons were the main group of constituents in three of the samples (P. capense, P. nigrum and P. umbellatum), whereas for the other species (P. guineense) phenylpropanoid deri...

Extinction risks of Amazonian plant species.

Estimates of the number, and preferably the identity, of species that will be threatened by land-use change and habitat loss are an invaluable tool for setting conservation priorities. Here, we use collections data and ecoregion maps to generate spatially explicit distributions for more than 40,000 vascular plant species from the Amazon basin (representing more than 80% of the estimated Amazoni...

Oxygenated volatiles from Amazonian floodplain tree species

Anticholinesterase and antityrosinase activities of ten piper species from malaysia.

PURPOSE The aim of this study was to investigate acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and antityrosinase activities of extracts from ten Piper species namely; P. caninum, P. lanatum, P. abbreviatum, P. aborescens, P. porphyrophyllum, P. erecticaule, P. ribesioides, P. miniatum, P. stylosum, and P. majusculum. METHODS Anticholinesterase and antityrosinase activities were e...

High levels of cryptic species diversity uncovered in Amazonian frogs.

One of the greatest challenges for biodiversity conservation is the poor understanding of species diversity. Molecular methods have dramatically improved our ability to uncover cryptic species, but the magnitude of cryptic diversity remains unknown, particularly in diverse tropical regions such as the Amazon Basin. Uncovering cryptic diversity in amphibians is particularly pressing because amph...