Streptomyces 1,8 cineole

Traditionally, the majority of the studies in this area have emphasized the analysis of microorganisms, in particular of soil actinomycetes, as the most relevant source of potential herbicide agents. The plant kingdom, however, has also been explored for the discovery of new herbicides. So far, bialaphos, originally isolated from different Streptomyces strains, is the only commercial herbicide derived from a microbial source. On the other hand, cymethylin, an analog of the mono terpenoid 1,8-cineole, as well as... 

The production of new materials for the aroma and fragrance industry was the powerful driving force in the research on the hydroxylation of terpenes [924, 1105-1107]. For instance, 1,4-cineole, a major constituent of eucalyptus oil, was regioselectively hydroxylated by Streptomyces griseus to give 8-hydroxycineole as the major product along with minor amounts of exo- and cnJo-2-hydroxy derivatives, with low optical purity (Scheme 2.151) [1108]. On the other hand, when Bacillus cereus was used, (2R)-exo- and (2/ )-en o-hydroxycineoles were exclusively formed in a ratio of 7 1, both in excellent enantiomeric excess [1109]. 

Streptomyces bottropensis, SY-2-1 biotransformed 1,8-cineole (122) stereochemically to (-H)-2a-hydroxy-l,8-cineole (125b) as the major product and (+)-3a-hydroxy-l,8-cineole (123b) as the minor product. Recovery ratio of 1,8-cineole metabolites as ether extract was ca. 30% in Streptomyces bottropensis, SY-2-1 (Noma and Nishimura, 1980,1981) (Figure 14.135). 

FICU RE 14.136 Biotransformation of 1,8-cineole (122), (+)-3a-hydroxy-l,8-cineole (123b), (+)-3p-hydroxy-l,8-cineole(123a), and (+)-3-oxo-l,8-cineole (126a) by Streptomyces ikutamanensis, Ya-2-1. (Modified from Noma, Y. and H. Nishimura, 1981. Annual Meeting of Agricultural and Biological Chemical Society, Book of abstracts, p. 196.)... 

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