Antifeedant, Antifungal Cryptic Polyketides with Six Structural Frameworks from Tea Endophyte Daldinia eschscholtzii Propelled by the Antagonistic Coculture with Phytopathogen Colletotrichum pseudomajus and Different Culture Methods.

The antagonistic coculture with tea phytopathogen Colletotrichum pseudomajus induces antifungal cryptic metabolites from isogenesis endophyte Daldinia eschscholtzii against tea phytopathogens. Sixteen new polyketides with six structural frameworks including ten cryptic ones, named coldaldols A-C (1-3), collediol (5), and daldinrins A-L (10-20 and 23), were found from the coculture of C. pseudomajus and D. eschscholtzii by different culture methods. The unique framework of compounds 11 and 12 featured a benzopyran-C7 polyketone hybrid, and compounds 13-16 were characterized by the novel benzopyran dimer. The structures were determined mainly by spectroscopic methods, including extensive one-dimensional (1D), two-dimensional (2D) NMR, high resolution electrospray ionisation mass spectroscopy (HRESIMS), ECD calculation, and single-crystal X-ray diffraction. The configuration of acyclic compounds 5 and 18 were determined by application of the universal NMR database. Most compounds showed significant antifungal activities against the tea pathogens C. pseudomajus and Alternaria sp. with MICs of 1-8 µg/mL. Compound 12 had stronger antifungal activity than that of positive drug nystatin. The ether bond at C-4 of the benzopyran derivative increased the antifungal activity. Compounds 4-9 and 11-23 showed antifeedant activities against silkworms with feeding deterrence indices of 15-100% at the concentration of 50 µg/cm2.

The antifeedant and antifungal cryptic metabolites isolated from tobacco endophytes induced by host medium and coculture.

Four new cryptic metabolites including one fumagillol derivative (2), one cyclohexenone derivative (4), one 10-membered lactone (5), and one natural 4-epi-brefeldin C (8), along with seven known compounds were found from isogenesis endophytes Aspergillus fumigatus, Penicillium janthinellum, Nigrospora sp., and Stagonosporopsis sp. induced by host Nicotiana tabacum medium and co-culture. The structures were determined mainly by spectroscopic methods, including extensive 1D, 2D NMR, MS techniques, ECD calculation, and Mosher's method. Compound 2 possessed a novel 1, 3-dioxetane residue and cyclohexane-containing terpenoid skeleton. Compounds 2, 4-7 and 10 showed significant antifungal activities against the plant pathogen Nigrospora sp. with MICs of 1 µg/mL. 2, 4, 5-7, and 10 indicated antifungal activities against Penicillium janthinellum, Aspergillus fumigatus, Phomopsis sp., and Alternaria sp. with MICs ≤8 µg/mL. Compounds 2, 6-8, and 10 (50 µg/cm2) and microbial fermentation extracts (100 µg/cm2) showed antifeedant activities against silkworms with feeding deterrence indices of 21-100%.

The induced cryptic metabolites and antifungal activities from culture of Penicillium chrysogenum by supplementing with host Ziziphus jujuba extract.

The productions of cryptic metabolites including three undescribed drimane sesquiterpenoids, penicichrins A-C, and three known compounds from Penicillium chrysogenum were activated by the host Ziziphus jujuba medium. The structures were established by comprehensive analysis of spectroscopic data. The spiro ß-lactone, and gem-dimethyl dihydroxylation in induced penicichrins A-C were rare in natural products. Cryptic metabolites, monaspurpurone was first found in Penicillium. 4-Methoxy-3-methylgoniothalamin, and 2-hydroxy-l-phenyl-l,4-pentanedione were second example of isolation. Penicichrin A, monaspurpurone, 4-methoxy-3-methylgoniothalamin, physcion, ergosterol, and ergosta-7,22-dien-3ß-ol had antifungal activities against phytopathogens, P. chrysogenum, Alternaria alternata and Aspergillus fumigatus with MICs ≤2 µg/mL, and 2-hydroxy-l-phenyl-l,4-pentanedione had flowering activity. So the chemical constituents from Z. jujuba could induce the productions of cryptic metabolites with plant growth-promoting activity from endophyte P. chrysogenum.

[A new lignan from Euscaphis konishii].

The chemical constituents from the extract of the twigs of Euscaphis konishii with anti-hepatoma activity were investigated, twelve compounds by repeated chromatography with silica gel, Sephadex LH-20 and preparative-HPLC. The structures of the chemical components were elucidated by spectroscopy methods, as konilignan(1),(7R, 8S)-dihydrodehydrodico-niferylalcohol-9-O-ß-D-glucopyranoside(2),illiciumlignan B(3),threo-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-panediol(4),erythro-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-panediol(5), matairesinol(6), wikstromol(7), isolariciresinol(8),(+)-lyoniresinol(9), 4-ketopinoresinol(10), syringaresin(11), and vladinol D(12). Among them, compound 1 is a new lignan. Compounds 10 and 12 had moderate inhibitory activity on HepG2 cells, with IC_(50) values of 107.12 µmol·L~(-1) and 183.56 µmol·L~(-1), respectively.

Chemical Constituents and Biological Activity Profiles on Pleione (Orchidaceae).

Pleione (Orchidaceae) is not only famous for the ornamental value in Europe because of its special color, but also endemic in Southern Asia for its use in traditional medicine. A great deal of research about its secondary metabolites and biological activities has been done on only three of 30 species of Pleione. Up to now, 183 chemical compounds, such as phenanthrenes, bibenzyls, glucosyloxybenzyl succinate derivatives, flavonoids, lignans, terpenoids, etc., have been obtained from Pleione. These compounds have been demonstrated to play a significant role in anti-tumor, anti-neurodegenerative and anti-inflammatory biological activities and improve immunity. In order to further develop the drugs and utilize the plants, the chemical structural analysis and biological activities of Pleione are summarized in this review.