Antifeedant and Antifungal Activities of Metabolites Isolated from the Coculture of Endophytic Fungus Aspergillus tubingensis S1120 with Red Ginseng.

A new globoscinic acid derivative, aspertubin A (1) along with four known compounds, were obtained from the co-culture of Aspergillus tubingensis S1120 with red ginseng. The chemical structures of compounds were characterized by using spectroscopic methods, the calculated and experimental electronic circular dichroism. Panaxytriol (2) from red ginseng, and asperic acid (4) showed significant antifeedant effect with the antifeedant rates of 75 % and 80 % at the concentrations of 50 µg/cm2 . Monomeric carviolin (3) and asperazine (5) displayed weak attractant activity on silkworm. All compounds were assayed for antifungal activities against phytopathogens A. tubingensis, Nigrospora oryzae and Phoma herbarum and the results indicated that autotoxic aspertubin A (1) and panaxytriol (2) possessed selective inhibition against A. tubingensis with MIC values at 8 µg/mL. The co-culture extract showed higher antifeedant and antifungal activities against P. herbarum than those of monoculture of A. tubingensis in ordinary medium. So the medicinal plant and endophyte showed synergistic effect on the plant disease resistance by active compounds from the coculture of A. tubingensis S1120 and red ginseng.

The chemical diversity, the attractant, anti-acetylcholinesterase, and antifungal activities of metabolites from biocontrol Trichoderma harzianum uncovered by OSMAC strategy.

Eight new compounds (1-8) were discovered from Trichoderma harzianum associated with edible mushroom by the one strain many compounds (OSMAC) strategy. Triharzianin A (1) is the first naturally scaffold characterized by a C13-prostaglandin skeleton. The configurations of 1-3, and 5 were determined by the Mosher's method, experimental and calculated ECD spectra, and plausible biosynthesis of stereospecific epoxidation. Most compounds indicated obvious feeding attractant activities to silkworm with attraction rates at 30-90%. Compound 7 showed anti-acetylcholinesterase (anti-AChE) activity with a ratio of 29% at a concentration of 50 µM for insecticidal potential. So 2,​3-​dialkylchromone (7) had potential of chemical entrapment and killing of insects. Compounds 2, 3 and 7-11 showed antifungal activities against Aspergillus fumigates, and Trichoderma sp. from mushroom with MICs ≤ 300 µM. The four fermentation extracts also indicated obvious feeding attractant activities to silkworm for the activities brought by active metabolites from T. harzianum. The material base of biocontrol induced by the interaction of host-fungal symbiont can be investigated by the antifungal metabolites against pathogen fungi.