Isolation and identification of bioactive compounds from Antrodia camphorata against ESKAPE pathogens.

Antimicrobial resistance is a major threat to human health globally. Antrodia camphorata was grown in a malt/yeast extract broth liquid medium for 15 days. Then, 4-L fermentation broth was harvested, yielding 7.13 g of the ethyl acetate extract. By tracing the antimicrobial activity, 12.22 mg of the antimicrobial compound was isolated. The structure of 5-methyl-benzo [1,3]-dioxole-4,7-diol (MBBD) was elucidated using NMR and MS data analyses. The antibacterial activity of MBBD was detected through the microbroth dilution method. MBBD exhibited broad-spectrum antibacterial activity. The minimum inhibitory concentration (MIC) range of MBBD for drug-resistant pathogenic bacteria was 64-256 µg/mL, with the lowest MIC observed for Acinetobacter baumannii (64 µg/mL), followed by Pseudomonas aeruginosa (MIC = 128 µg/mL). Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli were also sensitive, with an MIC of 256 µg/mL. The MIC range of MBBD against 10 foodborne pathogens was 12.5-100 µg/mL. Based on the results of this study, MBBD exhibits broad-spectrum antibacterial activity, particularly demonstrating excellent inhibitory effects against A. baumannii. MBBD will be good candidates for new antimicrobial drugs.

Chronic ethanol exposure during adolescence impairs simple spike activity of cerebellar Purkinje cells in vivo in mice.

Cerebellar Purkinje cells (PCs) play critical roles in motor coordination and motor learning through their simple spike (SS) activity. Previous studies have shown that chronic ethanol exposure (CEE) in adolescents impairs learning, attention, and behavior, at least in part by impairing the activity of cerebellar PCs. In this study, we investigated the effect of CEE on the SS activity in urethane-anesthetized adolescent mice by in vivo electrophysiological recordings and pharmacological methods. Our results showed that the cerebellar PCs in CEE adolescent mice expressed a significant decrease in the frequency and an increase in the coefficient of variation (CV) of SS than control group. Blockade of ɤ-aminobutyric acid A (GABAA) receptor did not change the frequency and CV of SS firing in control group but produced a significant increase in the frequency and a decrease in the CV of SS firing in CEE mice. The CEE-induced decrease in SS firing rate and increase in CV were abolished by application of an N-methyl-D-aspartate (NMDA) receptor blocker, D-APV, but not by anα-amino-3-hydroxy-5-methyl -4-isoxazolepropionic acid (AMPA) receptor antagonist, NBQX. Notably, the spontaneous spike rate of molecular layer interneurons (MLIs) in CEE mice was significantly higher than control group, which was also abolished by application of D-APV. These results indicate that adolescent CEE enhances the spontaneous spike firing rate of MLIs through activation of NMDA receptor, resulting in a depression in the SS activity of cerebellar PCs in vivo in mice.

A novel chloro-substituted pentenamide from the fruiting bodies of Amanita virgineoides.

One unusual chloro-substituted pentenamide, (3R)-4-chloro-3-hydroxy-4-pentenamide (1), together with 11 known compounds (2-12) were isolated from the fruiting bodies of Amanita virgineoides. The structure of 1 including the absolute configuration was characterized by extensive spectroscopic analyses and quantum calculation. Compound 1 displayed no obvious activity against herpes simplex virus (HSV), human enterovirus 71 (EV71) or coxsackievirus B3 (CVB3).

The Use of a Combination of RDC and Chiroptical Spectroscopy for Determination of the Absolute Configuration of Fusariumin A from the Fungus Fusarium sp.

A new alkylpyrrole derivative, fusariumin A (1), was isolated from the culture broth of the fungus Fusarium sp. The absolute configuration of fuasiumin A has been established as (2'R,3'R) using a combination of RDC (residual dipolar coupling)-based NMR and DFT-supported chiroptical spectroscopy. It is worth to note that in this study without the aid of the RDC analysis, an unambiguous determination of configuration and conformation was not feasible due to the excessive conformational possibilities of this open-chain compound.

Five new phenolic compounds from Dendrobium aphyllum.

One new phenanthrene, aphyllone A (1) and four new bibenzyl derivatives, aphyllone B (2) and aphyllals C-D (3-5), together with nine known compounds (6-14), were isolated from the stems of Dendrobium aphyllum (Roxb.) C. E. Fischer. The structures of these new compounds were elucidated by means of extensive spectroscopic analyses, and the absolute configuration of compound 1 was determined by single crystal X-ray diffraction and quantum calculations. Compounds 6, 8 and 14 inhibited NO production at the concentration of 25 µM in LPS-stimulated RAW264.7 cells with the inhibition (%) of 32.48, 35.68, and 38.50. Compound 2 possessed significant DPPH radical scavenging activity with scavenging percentage of 87.97% at the concentration of 100 µg/mL.

Nine new farnesylphenols from the basidiomycete albatrellus caeruleoporus.

Nine previously-unreported farnesylphenols, involving eight neogrifolin derivatives (1-8) and one grifolin analogue (9), together with three known compounds, were isolated from the fruiting bodies of the mushroom Albatrellus caeruleoporus. Their structures were elucidated as (S)-17-hydroxy-18,20-ene-neogrifolin (1), (S)-18,19-dihydroxyneogrifolin (2), (S)-9-hydroxy-10,22-ene-neogrifolin (3), (9S,10R)-6,10-epoxy-9-hydroxyneo grifolin (4), (9S,10R)-6,9-epoxy-10-hydroxyneogrifolin (5), (-)-13,14-dihydroxyneogrifolin (6), albatrelin G (7), albatrelin H (8), and one grifolin analogue, (S)-10-hydroxygrifolin (9), grifolin (10), neogrifolin (11), and albatrellin (12) by extensive spectroscopic analyses and chemical methods. Compounds 7 and 8 showed weak cytotoxic activity to cell lines HL-60, SMMC-7721, A-549, and MCF-7, in vitro.

Two new sesquiterpenoids from the fungus Ceriporia alachuana.

Two new sesquiterpenoids, tremulenolide D (1) and muurolane-10ß,15-diol (2), together with four known sesquiterpenoids, tremulenediol A (3), 2ß-hydroxy-α-candinol (4), epicubenol (5), and 3ß-hydroxy-δ-candinol (6), were isolated from cultures of the fungus Ceriporia alachuana. The structures of new compounds were determined by extensive spectroscopic analyses. Structurally, compounds 1 and 3 are tremulane-type sesquiterpenoids with an unusual perhydroazulene carbon skeleton.

Meroterpenoid pigments from the basidiomycete Albatrellus ovinus.

Eight grifolin derivatives, involving three new monomers, albatrelins A-C (1-3), three novel dimers (meroterpenoid pigments), albatrelins D-F (4-6), and two known ones, 6a,7,8,9,10,10a-hexahydro-3,6,9-trimethyl-6-(4-methyl-3-penten-1-yl)-1,9-epoxy-6H-dibenzo[b,d]pyran (7) and confluentin (8), were isolated from Albatrellus ovinus. Their structures were established by extensive spectroscopic analysis. The absolute configurations of compounds 2-4 were determined as 9R by comparing their optical rotations with data reported in the literature. Albatrelin F (6) was isolated as a pair of C-2' tautomers with a ratio of 1.3:1. Confluentin (8) showed weak cytotoxicity against four human tumor cell lines, HL-60, SMMC-7712, A-549, and MCF-7, in vitro.