Secondary Metabolites and PI3K Inhibitory Activity of Colletotrichum gloeosporioides, a Fungal Endophyte of Uncaria rhynchophylla.

In the present study, nine compounds (1-9) were isolated from Colletotrichum gloeosporioides (an endophytic fungus from Uncaria rhynchophylla) which was cultured in wheat bran medium. Their structures were elucidated as 4-Epi-14-hydroxy-10, 23-dihydro-24, 25-dehydroaflavinine (1), 10, 23-Dihydro-24,25 -dehydro-21-oxoaflavinine (2), Ergosterol (3), Ergosterol peroxide (4), Mellein (5), 4, 5-dihydroblumenol A (6), Colletotrichine A (7), Cyclo(L-leucyl-L-leucyl) (8), and Brevianamide F (9) based on NMR spectral data, as well as comparing with previous literature data. This is the first report about the isolation of compounds 1-2, 6, and 8-9 from Colletotrichum genus. All compounds were tested for their phosphoinositide 3-kinase (PI3Kα) inhibitory activity. Compounds 8 and 9 showed potent PI3K α inhibitory activity with IC50 values of 38.1 and 4.8 µM, respectively, while the other compounds showed very weak activity at a concentration of 20 µg/mL.

Stephtetrandrine A-D, bisbenzylisoquinoline alkaloids from Stephania tetrandra.

Four undescribed bisbenzylisoquinoline alkaloids, designated as Stephtetrandrine A-D, were isolated from the roots of Stephania tetrandra. Their structures were elucidated by IR, HRESIMS, ECD spectra, 1 D and 2 D NMR spectra and comparison with the literature data. Additional five known compounds (limacine, tetrandrine, N-trans-Feruloyltyramine, 2'-N-chloromethyltetrandrine, 2,2'-N-N-dichloromethyltetrandrine) were also isolated. N-trans-Feruloyltyramine was isolated from Stephania tetrandra for the first time. The isolated compounds were tested for monoamine oxidase, acetylcholinesterase, phosphoinositide 3-kinase α and human hepatoma cell HepG2 inhibitory activities. Stephtetrandrine C showed obvious inhibitory effect on human hepatoma HepG2, with IC50 value of 16.2 µM. Limacine and 2'-N-chloromethyltetrandrine showed moderate monoamine oxidase inhibitory effect with the IC50 values of 37.7 and 29.2 µM, respectively.

A norbisabolane and an arabitol benzoate from Talaromyces marneffei, an endophytic fungus of Epilobium angustifolium.

A norbisabolane and an arabitol benzoate, Talaromarnine A (1), Talaromarnine B (2), together with eight known compounds were obtained from cultures of Talaromyces marneffei, an endophytic fungus of Epilobium angustifolium. Their structures were elucidated by IR, MS, 1D and 2D NMR spectra, and their absolute configuration was determined by single-crystal X-ray diffraction and molecular computation. These compounds were tested for monoamine oxidase, acetylcholinesterase and PI3K inhibitory activity, but no compounds exhibited significant activities.

Wortmannine H, a phenylpentenol isolated from an endophytic fungus, Talaromyces wortmannii LGT-4.

A new phenylpentenol, wortmannine H (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. The structure of 1 was elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated optical rotatory dispersion (ORD). Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activities of 1 was also tested. The compound did not show good biological activity.

Chemical Composition and Biological Activities of Endophytic Fungus Talaromyces Wortmannii LGT-4, Cultured in CYM Medium.

In the present study, nine compounds (1-9) were isolated from Talaromyces wortmannii LGT-4 (an endophytic fungus from Tripterygium wilfordi) which was cultured in CYM Medium. Their structures were determined as 4-hydroxyphthalide (1), Fumitremorgin C (2), Ergosterol (3), 3-(2-hydroxypropyl)-8-hydroxy-3,4- dihydroisocoumarin (4), Cis-cyclo(L-Ala-L-Pro) (5), 6-Amino-3-(4-hydroxybenzyl)- 1,4-diazonane-2,5-dione (6), Aspergillumarin B (7), Deacetylisowortmin B (8), and Entonaemin A (9) based on NMR spectral data, as well as comparing with previous literature data. This is the first report of the isolation of compounds 1-2 and 4-7 from Talaromyces genus. All compounds were tested for their monoamine oxidase and phosphoinositide 3-kinase (PI3Kα) inhibitory activities. Compound 1, 5 showed moderate anti-monoamine oxidase activity with IC50 value of 35 µg/mL, 28 µg/mL, respectively. Compound 9 showed PI3Kα inhibitory activity with IC50 value of 10.3 µg/mL.

Two new compounds, Talaromycin A and B, isolated from an endophytic fungus, Talaromyces aurantiacus.

Two new compounds Talaromycin A (1) and Talaromycin B (2) were isolated from a liquid culture of Talaromyces aurantiacus. The structures of 1 and 2 were elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated electronic circular dichroism spectra. Additional known compounds (3-6) were also isolated. These compounds were tested for monoamine oxidase, acetylcholinesterase and PI3K inhibitory activity, but showed only weak activity.

A new wortmannine derivative from a Tripterygium wilfordii endophytic fungus Talaromyces wortmannii LGT-4.

A new wortmannine derivative named wortmannine E (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. Its structure was established by 1D and 2D NMR spectra.

Secondary Metabolites and Biological Activities of Talaromyces sp. LGT-2, an Endophytic Fungus from Tripterygium Wilfordii.

In the present study, eleven compounds (1-11) including nine alkaloids (1-9), one triterpenoid saponin (10) and one formamide (11) were isolated from Talaromyces sp. LGT-2, an endophytic fungus from Tripterygium wilfordi. Their structures were determined based on NMR and ESI-MS spectral data, as well as comparing previous literature data. This is the first report of the isolation of alkaloids (1-9) from Talaromyces genus. In the next step, all compounds were screened for their anti-monoamine oxidase, anti-acetylcholinesterase, antibacterial and antitumor activities. Compound 11 showed moderate anti-monoamine oxidase activity with IC50 value of 61 µM; compounds 3, 4, 8 showed weaker anti-acetylcholinesterase activity; compounds 1, 3, 4, 7, 8, 9 showed moderate antibacterial activities; compounds 7, 8, 9 showed cytotoxicity against B16 cancer cell line with inhibitory rate of 86%, 82%, 78%, respectively, at the concentration of 500 µg/mL.

A rapid thin-layer chromatography bioautographic method for detecting the monoamine oxidase inhibitors in plants.

It is well known that the isolation of monoamine oxidase (MAO) inhibitors from natural sources is an important strategy for drug development in the treatment of depression, Parkinson's disease and Alzheimer's disease. The present work describes developing a thin-layer chromatography (TLC) bioautographic method for detecting MAO inhibitors from plant extracts. The basic principle of the method is that the enzyme oxidises tryptamine into an aldehyde which in turn reacts with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide to form a blue formazan which makes a blue-coloured background on the TLC plates. Inhibitors of MAO produced white spots on the background. The new TLC bioautographic method has several advantages such as lower consumption of the enzyme, shorter experimental time, more easily observed background of TLC plate and better reproducibility. The detection limits were 10 ng for several known MAO inhibitors.