Pelargonium roseum

Pelargonic acid CgHnCOOH In essence of Pelargonium roseum, in sugar beet distillate and potato distillate. 

Branched-chain amino acids as precursurs of plant isoprenoids L-Leucine and L-valine, when fed to germinating pea seeds (Pisum sativum) were incorporated into squalene and 6-amyrin [39]. Chemical degradation by ozonolysis of the radioactive squalene revealed an equal distribution of the radioactivity in the IPP-derived (4 portions per molecule) and the DMAPP-derived moieties (2 portions per molecule). However, an unbalanced distribution in favor of the DMAPP-derived moiety of monoterpenoids was found after feeding radioisotopically labeled L-leucine, L-valine, DL-alanine, acetate, and R,S-MVA to intact plants of Cinnamomum camphora and of Pelargonium roseum [40]. The relatively low incorporation of amino acids was explained by several hypotheses a) the radioactivity of amino acids is scattered into other metabolites rather than monoterpenoids b) there is a great pool of the amino acids which leads to dilution of radioactivity, and c) the low permeation of the amino acids into the biosynthetic site of monoterpenoids [40]. The DMAPP-derived moiety of monoterpenoids, biosynthesized from [U- C]leucine and [U- ]valine was labeled with more than 64% of the incorporated tracers, while this moiety when derived from [2- " C]MVA contained less than 32% of the tracers [40]. This lends support to the interpretation that both amino acids are incorporated not via MV A, but by an alternate route, e,g, a combination of the well known mammalian leucine degradation pathway and a reversal of the MVA shunt (see below). The distribution pattern in monoterpenoids after administration of [2- ]alanine was similar to that after incorporation of MVA, which indicates that alanine is first metabolized to acetyl-CoA, which then constructs preferentially the IPP-derived moiety of the monoterpenoids via MVA [40]. 

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