Interconversion of trans, trans and cis, trans farnesol by enzymes from Andrographis

Biosynthesis of trans,trans- and cis,trans-farnesols by soluble enzymes from tissue cultures of Andrographis paniculata

“…Similar results, published at this time, came from isomerization of [1-2H2]-trans,trans-farnesol by the fungus Helminthosporium sativum (Suzuki & Marumo, 1972). We could also demonstrate (Overton & Roberts, 1974b) that [4,8,12-14C3,1-3H2]-trans,trans-famesolloses50% of its 3H when it is isomerized to cis,trans-farnesol, as does [4,8,12-14C3,1-3H2]-cis,trans-farnesol on being isomerized to trans,trans-farnesol, in accordance with the equilibria set out in Scheme 1. These results support the formation of cis,trans-farnesol from trans,trans-farnesol and the reverse process via aldehydes, and make it unnecessary in this system Vol.…”

Enzymic formation of sesquiterpenes

“…The tricyclic sesquiterpene (-)-patchoulol (patchouli alcohol, (49)), an important perfumery raw material, is the major component of the essential oil of patchouli (Pogestomon cablin).nl Cell-free extracts of patchouli leaves have been shown to catalyze the conversion of farnesyl pyrophosphate to patchoulol along with a mixture of cyclic olefins, including a-, ft-, and 7-patchoulene (50-52) as well as a-bulnesene (53) and aguaiene (54). 118 The mechanism of the cyclization has been investigated by Croteau. Incubation of [1-3H,12,13-14C]FPP with the 145000# supernatant of P. cablin leaf extracts gave patchoulol which was shown to retain tritium at C-l by a degradative sequence involving acid-catalyzed rearrangement and dehydration of 49 to /3-patchoulene (51), followed by oxidative cleavage and acid-catalyzed cyclization of the resulting dione to give the cyclohexenone derivative 55, which was devoid of tritium (Scheme 32).…”

Production of essential oils and flavours in plant cell and tissue cultures. A review

“…The stereochemistry of the interconversion of trans, trans-and cis, trans farnesols by a cell-free system of Andrographis paniculata tissue cultures has been studied [105,106,107]. When tt-farnesol was isomerized to ct-farnesol, the 1-pro-R hydrogen of tt-farnesol was retained and the 1-pro-S hydrogen was lost; by contrast, conversion of ct-farnesol proceeded with retention of the 1-pro-S and loss of the l-pro-R hydrogen of ct-farnesol.…”