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Various mono- and disubstituted cinnamic acid derivatives and aromatic carboxylic acids with saturated side chains were incubated mainly with Bacillus, Candida, Hansenula, and Saccharomyces strains. The cinnamic acids carrying a hydroxy- and/or a methoxy group at the 3- and/or 4-position of the benzene ring were decarboxylated with high yields. Most of the reactions were terminated within 24 to 48 h. Substitution at other ring positions afforded also decarboxylation, but at much lower yields. Derivatives with other residues like methyl, chloride, or bromide were not transform ed to the respective styrene. None of the saturated aromatic carboxylic acids could be decarboxylated by the strains used.

Corynespora cassiicola DSM 62474 and Diplodia gossypina ATCC 10936 were found to cleave some acyclic terminal terpendiols and prolongate them later by addition of a C2-unit to afford 1,2-dihydroxy-propyl-compounds. The enzymes involved in this reaction from both microorganisms displayed a strong stereoselectivity which is completely different in both strains. The stereochemi­cal requirements of the substrates for both strains and the mechanism were elucidated by using closely related substrates. The absolute configuration of the diols were solved by correlation with com pounds of known absolute configuration.

The accumulation of volatile metabolites in liquid cultures of the basidiomycete Gloeophyllum odoratum CBS 444.61 was studied after cultivation on defined synthetic liquid culture medium containing glucose (2%), asparagine (0.15%), and mineral salts. The composition of the steam volatile compounds differed distinctly from that obtained with another, previously investigated strain of this species. Two major constituents, the bicyclic sesquiterpene alcohol drimenol and a linalool derivative, 3,7-dimethyl-3-hydroxy-6-octenic acid methyl ester, could be identified by mass spectral data and 1H and 13C NMR spectroscopy. Besides several monoterpene alcohols, other minor constituents were trans-linalool oxide and 1-octen-3-ol. 3,7-Dimethyl-3-hydroxy-6-octenic acid methyl ester is described for the first time as a natural product.

The brown-rot fungus Lentinus lepideus (Fr.: Fr.) Fr. FPRL 7B (Basidiomycotina) was cultivated on a defined synthetic liquid medium containing glucose (2%), isoleucine (0.15%), and mineral salts for 105 days. The steam distillate was separated by column chromatography. Three novel sesquiterpene ethers with muurolane skeleton (lentideusether, isolentideusether, and 10-hydroxylentideusether) were isolated and their structures elucidated by spectroscopic methods, in particular by 1H NMR spectra and by two-dimensional 1H/1H- and 13C/1H-chemical shift correlation. These compounds are described for the first time as natural products. As a further metabolite, the acyclic sesquiterpene alcohol terrestrol was identified

Biotransformation of cedrol with 5 different strains afforded 8 previously undescribed hydroxy-cedrols. The attack came from a hemisphere centered at C-12 approximately. At two positions epimeric pairs were formed, which could be avoided by using different strains. Contrary to previous studies of other groups we found the 2-and 12-hydroxylations as main reactions. Cedrene needed prolonged fermentation and gave lower yields than cedrol. Apart from allylic hydroxylations the oxidation pattern by Corynespora cassiicola DSM 62474 of cedrene and cedrol was the same. The structures of the metabolites were elucidated by 2D NMR techniques.

Humulene was transform ed by strains of Chaetomium cochlioides and Diplodia gossypina ATCC 10936 affording 33 new humulanes. The first step is a non-enantioselective epoxidation of the 1,2-double bond, whereas the subsequent hydroxylations were performed preferably at the 1R ,2R -epoxide. To proof these results the anti-1,2;8,9-diepoxide was synthesized and used as substrate. While the 1R ,2R ,8S,9S-antipode of this diepoxide was hydroxylated the other one was recovered unchanged. Diplodia gossypina ATCC 10936 gave the same products but differing in relative and absolute configurations.

The basidiomycete Lentinellus cochleatus CBS 201.47 was cultivated on a defined synthetic liquid culture medium containing glucose (2%), asparagine (0.15%), malt extract (0.2%), and mineral salts. 12 weeks old cultures produced a “sweet” odour with an anise-or cinnamon-like note. 3 major volatiles could be identified from the steam distillates by their GC/MS-and 1H NMR data. Predominant constituents were the acyclic sesquiterpene alcohols trans-nerolidol (41.4%) and fokienol (14.8%). 2,2-Dimethyl-6-formylchromene (6.1%) is described for the first time as a natural product. Besides these, 15 minor constituents could be identified or chemically charac­terized, respectively, the majority of them being sesquiterpene hydrocarbons and alcohols.