Ming-Der Wu

Maleimide and Maleic Anhydride Derivatives from the Mycelia of Antrodia cinnamomea and Their Nitric Oxide Inhibitory Activities in Macrophages

On cultivation of the fungus Antrodia cinnamomea (BCRC 36799) on a medium, the mycelium was extracted and evaluated for nitric oxide (NO) inhibitory activity. Bioactivity-directed fractionation led to the isolation of two new maleimide derivatives, antrocinnamomins A (1) and B (2), and two new maleic anhydride derivatives, antrocinnamomins C (3) and D (4), along with three known compounds, 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]furan-2,5-dione (5), 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrole-2,5-dione (6), and 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrol-1-ol-2,5-dione (7). Structural elucidation of compounds 1-4 was carried out by spectroscopic data. Compound 1 displayed significant inhibitory effect on nitric oxide (NO) production.

Antioxidant activities of extracts and metabolites isolated from the fungus Antrodia cinnamomea

Three different solvent partitions (n-hexane, ethyl acetate [EtOAc] and n-BuOH) of the culture broth from Antrodia cinnamomea were assayed with two different radical scavenging methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and superoxide radical scavenging (SOD) assay. The EtOAc layer exhibited the best antioxidant activity. Two major antioxidant metabolites were isolated from the active EtOAc layer. The antioxidant activities of compounds 1–6 were further evaluated by DPPH, SOD and trolox equivalent antioxidant capacity (TEAC) assays. Compounds 3 and 5 showed stronger free radical scavenging than the reference BHA, ED50 = 1.36 and 34.24 µM. Compound 5 displayed moderate SOD activity (ED50 = 310.0 µM), and its antioxidant capacity of TEAC value was 2.2 mM trolox equivalency.

Monasnicotinates A-D, four new pyridine alkaloids from the fungal strain Monascus pilosus BCRC 38093.

Four new pyridine derivatives, monasnicotinates A–D (1–4) were isolated from the red yeast rice of Monascus pilosus BCRC 38093. Their structures were elucidated on the basis of physicochemical evidence, in-depth NMR spectroscopic analysis, and high-resolution mass spectrometry. Their inhibitory effects on NO production was also evaluated.

Isolation and structure determination of one new metabolite isolated from the red fermented rice of Monascus purpureus

The n-BuOH-soluble portion of the 95% EtOH extract of red fermented rice fermented with the yellow mutant of the fungus Monascus purpureus BCRC 38113 (Monascaceae) led to the isolation of one new pyran-2-one derivative, namely peroxymonascuspyrone (1), along with nine known compounds, monasfluore A (2), monasfluore B (3), 3-epi-betulinic acid (4), 3-epi-betulinic acid acetate (5), α-tocospiro A (6), friedelan-3-one (7), α-cadinol (8), anticopalol (9), and spathulenol (10). Interestingly, this is the first report of a naturally occurring pyran-2-one skeleton isolated from Monascus sp. Their structures and relative configurations were elucidated by spectroscopic methods, including 1D- and 2D-NMR (1H,1H-COSY, HMQC, HMBC and NOESY), as well as low- and high-resolution mass spectrometric analyses. In addition, cytotoxicities against MCF-7, NCI-H460 and SF-268 cancer cell lines were measured in vitro; the results revealed that these metabolites have no cytotoxicity against the selected tumour cells.

Six new metabolites produced by Colletotrichum aotearoa 09F0161, an endophytic fungus isolated from Bredia oldhamii

Six new compounds, colletobredins A–D (1–4) and colletomelleins A and B (5 and 6), along with 12 previously identified compounds, were isolated from the culture broth of Colletotrichum aotearoa BCRC 09F0161, a fungal endophyte residing in the leaves of an endemic Formosan plant Bredia oldhamii Hook. f. (Melastomataceae). The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESIMS and extensive 1D and 2D NMR techniques. The effects of some isolates on the inhibition of nitric oxide (NO) production in lipopolysaccharide-activated murine macrophage RAW264.7 cells were evaluated. All these compounds inhibited NO production in activated macrophages without any cytotoxicity at a concentration of 100 μM. Of these isolates, 1 showed weak NO inhibitory activity with IC50 value of 182.2 μM. To the best of our knowledge, this is the first report on isochroman glycoside metabolites (1–4) from the genus Colletotrichum.

Secondary Metabolites from the Endophytic Fungus Annulohypoxylon stygium BCRC 34024

A new γ-butyrolactone, annulostygilactone (1), along with nine known compounds consisting of seven benzenoids [p-hydroxybenzaldehyde (2), methylparaben (3), p-hydroxybenzoic acid (4), syringaldehyde (5), eugenol (6), vanillic acid (7), and ferulic acid (8)], and two triterpenoids [ursolic acid (9) and _-daucosterol (10)] were isolated from the endophytic fungus Annulohypoxylon stygium BCRC 34024. Their structures were determined based on their 1D and 2D NMR and HR-ESI-MS spectral data as well as comparison with previous literature data. All compounds were found for the first time in this species. It is worthy of note that this is the first report of secondary metabolites isolated from this fungus. The inhibitory effects of some isolates (compounds 1, 9, and 10) on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated macrophages were evaluated. Compound 1 showed stronger inhibition of NO production than the positive control quercetin.

Monascusazaphilones A–C, three new azaphilone analogues isolated from the fungus Monascus purpureus BCRC 38108

Investigation of the 95% EtOH extract of red yeast rice fermented with the pink mutant of the fungus Monascus purpureus BCRC 38108 led to the isolation of three new azaphilone derivatives, namely monascusazaphilones A–C (1–3), together with two known compounds. Compounds 1–3 were isolated from this species for the first time. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy together with HR–ESI–MS analysis and comparison of the spectroscopic data with those reported in the literatures. All isolates were evaluated for their inhibitory effects on nitric oxide (NO) production by macrophages. Among the isolates, compound 1 demonstrated stronger inhibition on NO production.

Phytochemical Investigation of Annulohypoxylon ilanense, an Endophytic Fungus Derived from Cinnamomum Species

Cultivation of the fungal strain Annulohypoxylon ilanense, an endophytic fungus isolated from the wood of medicinal plant Cinnamomum species, resulted in the isolation of one new furanoid derivative, ilanefuranone (1), one new pyrrole alkaloid, ilanepyrrolal (2), and one new biarylpropanoid derivative, ilanenoid (3), together with 22 known compounds, of which one α‐tetralone analog, (−)‐(4R)‐3,4‐dihydro‐4,6‐dihydroxynaphthalen‐1(2H)‐one (4) was isolated for the first time from a natural source. The structures were elucidated on the basis of physicochemical evidence, in‐depth NMR spectroscopic analysis, and high‐resolution mass spectrometry, and the antimycobacterial activities were also evaluated.

Secondary metabolites from the red mould rice of Monascus purpureus BCRC 38113

One new tetralone, monaspurpurone (1), was isolated from the EtOH extract of a yellow mutant of the fungus Monascus purpureus BCRC 38113 (Eurotiaceae) grown on rice, along with five known compounds, β-sitosteryl palmitate (2), ergosterol (3), ankaflavin (4), monascin (5) and p-nitrophenol (6). They were characterised on the basis of spectral analysis and comparison with literature data. All the isolates were also evaluated for the scavenging properties towards the DPPH in TLC autographic and spectroscopic assays.

SECONDARY METABOLITES ISOLATED FROM THE FUNGUS MONASCUS KAOLIANG-FERMENTED RICE

A chemical study of the EtOAc-soluble ethanolic extract of Monascus kaoliang BCRC 31506 (Eurotiaceae) fermented rice led to the isolation of a new furan-3-one derivative along with 9 known compounds, monascin (2), ankaflavin (3), N-trans-feruloyltyramine (4), vanillic acid (5), 4-acetonyl-3,5-dimethoxy-p-quinol (6), (+)-s-eudesmol (7), trans-phytol (8), aesculetin dimethyl ether (9) and (-)-matairesinol (10). Structure 1 is proposed for monascuskaoliaone on the basis of spectroscopic evidence (NMR, UV, IR, and HRMS). None of the compounds exhibited significant scavenging activity toward DPPH radical in bioautography or spectroscopic assays.