Chemical profile of the secondary metabolites produced by a deep-sea sediment-derived fungus Penicillium commune SD-118

Bioassay-guided fractionation of the crude extract from Penicillium commune SD-118, a fungus obtained from a deep-sea sediment sample, resulted in the isolation of a known antibacterial compound, xanthocillin X (1), and 14 other known compounds comprising three steroids (2-4), two ceramides (5 and 6), six aromatic compounds (7-12), and three alkaloids (13-15). Xanthocillin X (1) was isolated for the first time from a marine fungus. In the bioassay, xanthocillin X (1) displayed remarkable antimicrobial activity against Staphylococcus aureus and Escherichia coli, and significant cytotoxicity against MCF-7, HepG2, H460, Hela, Du145, and MDA-MB-231 cell lines. Meleagrin (15) exhibited cytotoxicity against HepG2, Hela, Du145, and MDA-MB-231 cell lines. This is the first report of the cytotoxicity of xanthocillin X (1).

Lithocarpinols A and B,a pair of diastereomeric antineoplastic tenellone derivatives from the deep-sea derived fungus Phomopsis lithocarpus FS508

Lithocarpinols A(1) and B(2), a pair of tenellone diastereoisomers with novel fused skeleton were isolated from the deep-sea derived fungus Phomopsis lithocarpus FS508. Their structures were elucidated by comprehensive spectroscopic analyses, X-ray diffraction and quantum molecular calculation. Their plausible biogenetic pathway featured an intriguing carbonyl-ene cyclization. Lithocarpinol A exhibited moderate inhibitory effect against HepG-2 and A549 tumor cell lines with IC_(50) values of 9.4 μmol/L and10.9 μmol/L,respectively.

Isolation and Neuroprotective Activity of Phenolic Derivatives from the Marine-Derived Fungus Penicillium janthinellum

A new phenolic compound, 6-(2-acetyl-3,5-dihydroxybenzyl)-4-hydroxy-3-methyl-2H-pyran-2-one(1), along with other six known phenolic derivatives(2-7), were isolated from the mangrove rhizosphere fungus Penicillium janthinellum HK1-6 cultured in potato dextrose broth medium containing 30 g L^(-1) of natural sea salt. The structure of the new compound(1) was elucidated by comprehensive analysis of spectroscopic data including 1D and 2D NMR spectra. The proposed biosynthetic pathway of compound 1 was also studied in this research. Interestingly, a brominated phenolic derivative, aryl bromide(compound 8), was obtained from this fungal strain cultured in medium containing 30 g L^-1 of NaBr instead of natural sea salt. Compound 8 is proposed as a new natural product and formed through bromination of compound 7 when the fungus was cultured with NaBr. The neuroprotective effect of compound 1 on oxygen-glucose deprivation(OGD)-induced injury was investigated in rat spinal cord astrocytes. MTT assay demonstrated that compound 1 can attenuate OGD-induced cell viability loss in rat spinal cord astrocytes.

New indole derivatives from endophytic fungus Colletotruchum sp. HK-08 originated from leaves of Nerium indicum

Objective: To study secondary metabolites from endophytic fungus Colletotruchum sp. HK-08 originated from the leaves of Nerium indicum.Methods: The compounds were isolated by various column chromatographic techniques, and their structures were elucidated by spectroscopic techniques [high resolution electrospray ionization mass spectroscopy(HRESIMS), one-dimensional(1D) and two-dimensional(2D) nuclear magnetic resonance spectroscopy(NMR)], as well as comparison with literature data. The Ellman method was used to determine the acetylcholinesterase(ACh E) inhibitory activity.Results: Four indole derivatives were identified from Colletotruchum sp. HK-08, including 6’-hydroxymonaspiloindole(1), 2-(2-oxoindolin-3-yl)ethyl 2-(4-hydroxyphenyl) acetate(2), 2-(2-oxoindolin-3-yl)ethyl 2-(2-hydroxyphenyl)acetate(3), and monaspiloindole(4). Compound 4 presented weak ACh E inhibitory activity with IC50value of(69.30 ± 6.27) μmol/L [tacrine as the positive control, with IC50value of(0.61 ± 0.07) μmol/L].Conclusion: Compounds 1–3 were new compounds, and compound 4 had weak ACh E inhibitory activity.

Isolation and characterization of three pairs of verrucosidin epimers from the marine sediment‑derived fungus Penicillium cyclopium and confguration revision of penicyrone A and related analogues

Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological diseases.Despite the signifcance of verrucosidins as neurotoxins,the absolute confgurations of most of the derivatives have not been accurately characterized yet.In this study,three pairs of C-9 epimeric verrucosidin derivatives,including the known compounds penicyrones A and B(1a/1b)and 9-O-methylpenicyrones A and B(2a/2b),the new compounds 9-O-ethylpenicyrones A and B(3a/3b),together with the related known derivative verrucosidin(4),were isolated and identifed from the culture extract of Penicillium cyclopium SD-413,which was obtained from the marine sediment collected from the East China sea.Their structures were established based on an in-depth analysis of nuclear magnetic resonances(NMR)and mass spectroscopic data.Determination of the absolute confgurations of these compounds was accomplished by Mosher’s method and time-dependent density functional theory(TDDFT)calculations of electronic circular dichroism(ECD)and optical rotation(OR).The confgurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute confguration of verrucosidin derivatives needs to be revised from(6S)to(6R).The 9R/9S epimers of compounds 1–3 were found to exhibit growth inhibition against some pathogenic bacteria,indicating that they have potential as lead compounds for the creation of antimicrobial agents.

Meroterpenthiazole A, a unique meroterpenoid from the deep-sea-derived Penicillium allii-sativi, significantly inhibited retinoid X receptor (RXR)-α transcriptional effect

A novel meroterpenoid,named meroterpenthiazole A(1),was isolated from the deep-sea-derived Penicillium allii-sativi.Its structure was established by extensive spectroscopic and computational methods.Meroterpenthiazole A bears a rare benzothiazole moiety in nature.Compound 1 significantly inhibited retinoid X receptor(RXR)-α transcriptional effect(K_(D)=12.3 μmol/L) through a novel binding mechanism.

Penicacids E-G, three new mycophenolic acid derivatives from the marine-derived fungus Penicillium parvum HDN17-478

Three new mycophenolic acid derivatives, penicacids E-G(1-3), together with three known analogues, mycophenolic acid(4), 4′-hydroxy-mycophenolic acid(5) and mycophenolic methyl ester(6), were isolated from a marine-derived fungus Penicillium parvum HDN17-478 from a South China Sea marine sediment sample. The structures of compounds 1-3 were elucidated by HRMS, NMR, and Mosher’s method. Among them, compounds 1 and 2 were the first examples of mycophenolic acid analogs with a double bond at C-3′/C-4′ position. The cytotoxicity of 1-6 was evaluated against the HCT-116, BEL-7402, MGC-803, SH-SY5 Y, HO-8910 and HL-60 cell lines, and compounds 4 and 6 showed potent cytotoxicity with IC50 values ranging from 1.69 to 12.98 μmol·L–1.

Rubratoxin C,a new nonadride derivative from an endophytic fungus Penicillium sp.F-14

One new nonadride derivative rubratoxin C （1） together with a known compound rubratoxin B （2） were isolated from an endophytic fungus Penicillium sp. F-14. Their structures were elucidated by various spectroscopic methods. Bioassays showed that 2 had moderate cytotoxic effect against HCT-8, BEL-7402, Ketr3, A2780, MCF-7 and BGC-823 human cancer cell lines, and 1 exhibited weak activity.

Cytotoxic diaporindene and tenellone derivatives from the fungus Phomopsis lithocarpus

Nine new compounds,including five natural rarely-occurring 2,3-dihydro-1H-indene derivatives named diaporindenes E−I(1−5),and four new benzophenone analogues named tenellones J−M(6−9)were isolated from the deep-sea sediment-derived fungus Phomopsis lithocarpus FS508.All the structures for these new compounds were fully characterized on the basis of spectroscopic data,NMR spectra,and ECD calculation and single-crystal X-ray diffraction analysis.The potential anti-tumor activities of compounds 1−9 against four tumor cell lines SF-268,MCF-7,HepG-2,and A549 were evaluated using the SRB method.Compound 7 exhibited cytotoxic activity against the SF-268 cell line with an IC50 value of 11.36μmol·L^(−1).

A CORRECTION OF SCHRDTER'S TEMPERATURE EQUIVALENCE EQUATION FOR FUNGUS GROWTH

Based on the experimental data of Cohen and Yarwood on growth curves of some hundred fungi, Schr(?)dter worked out a mathematical model, a function named temperature equivalence equation for fungus growth, to describe the growth curves in relation to temperature. Schr(?)dter’s model is valid in theoretical background and

PHOTOCHEMISTRY OF HYPOCRELLIN A (Ⅰ) PHOTOOXIDATION OF HYPOCRELLIN A

A new effective phototherapeutic drug from Hypocrella bambusae (B. et Br.) Sacc., which is a kind of parasitic fungus growing in Yunnan Province, China, has been successfully used in the treatment of White Lesions of Vulva upon irradiation with a visible ray. The main constituent of Hypocrellab ambusae (B. et Br.). Sacc., Hypocrellin A (Ⅰ), which is a derivative of 4.9-dihydoxyperylene-3,10-quinone, was separated and identified by Wan Xiangyi et al. in 1980. When I is exposed under the sunlight in solution for a long period of time, Ⅰ can be completely photooxidized to its peroxide Ⅱ, which does not retain its phototherapeutic activity at all. The possible pathway towards its oxidation has been suggested to go through an intermediate stage