The metabolites of Talaromycesflavus: Part 2. Biological activity and biosynthetic studies

Abstract

. Can. J. Chem. 68, 2095Chem. 68, (1990. The soil fungus Talaromycesjavus (Klocker) Stolk and Samson is an effective biological control for Verticillium wilt of eggplant (Solanurn melongena L.), a disease caused by the fungus Verticilliurn dahliae Kleb. The water soluble metabolites isolated from the broth when the fungus is grown in liquid still culture, hydroxymethylmaltol (I), 5,6-dihydro-3,5-dihydroxy-6-hydroxymethyl-2H-pyran-2-one (3), and D-glucono-l,4-lactone (5), do not show antifungal activity against V. dahliae; however, hydrogen peroxide displays this inhibition. This peroxide has been detected in the T.javus broth and it, together with 5, is the product of the glucose oxidase catalyzed oxidation of D-glucose. The results of the search for this antifungal activity are presented. [l-13C] Labelled sodium acetate was utilized as a precursor for studying the biosynthesis of the T. javus metabolites 4,6-dihydroxy-5-methylphthalide (7), methyl 4-carboxy-5-hydroxyphthalaldehydate (a), and talaroflavone (9). The incorporation of label into these compounds is discussed.

Marilines A–C: Novel Phthalimidines from the Sponge‐Derived Fungus Stachylidium sp.

“…Compounds 1 – 3 are related to their oxygen‐containing counterparts, phthalides, which are more common in nature 35. Biosynthetic studies focusing on phthalide structures, for example, for mycophenolic acid36 or for phthalide‐like metabolites isolated from Talaromyces flavus ,37 evidenced the tetraketide nature of the phthalide nucleus. Compounds 1 – 3 also possess the basic skeleton of the tetraketide 3‐methyl‐orsellinic acid, yet with the acetate‐derived methyl group in orsellinic acid replaced by an ethyl group in the precursor molecules of 1 – 3 38.…”

The Bioactive Secondary Metabolites from Talaromyces species

“…A phthalide derivative 109 and a spiro-phthalide derivative 110 were obtained from the organic extracts and from the water extracts of the soil fungus T. flavus [ 30 , 34 ]. Another phthalide compound FKI-0076 B, vermistatin 111 , was obtained from Talaromyces sp.…”

“…A six-membered ring lactone ( 118 ) was isolated from the water extracts of the soil fungus T. flavus [ 34 ]. Two lactones ( 119 and 120 ) were isolated from an endophytic fungus, a close relative of Talaromyces sp., found in association with Cedrus deodara .…”

“…Hydroxymethylmaltol ( 132 ) was isolated from the water extracts of the soil fungus T. flavus [ 34 ]. Funicone ( 133 ) and a new funicone derivative, 9,14-epoxy-11-deoxyfunicone ( 134 ), were isolated from the strain T. flaus IFM52668.…”

Marilones A–C, phthalides from the sponge-derived fungus Stachylidium sp.

“…They are produced by a wide range of organisms, i.e., by marine and terrestrial fungi belonging to genera such as Ascochyta [2], Aspergillus [3–5], Alternaria [6], Penicillium [7], Hericium [8] or Talaromyces [9], but also by plants and liverworts [1]. …”