Nine new azaphilones, including penicilazaphilones I–N (1, 2 and 6–9), epi-geumsanol D (3) and penidioxolanes C (4) and D (5) were isolated from the culture of the marine-derived fungus Penicillium sclerotiorum E23Y-1A. The structures of the isolates were deduced from extensive spectroscopic data (1D and 2D NMR), high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. All the azaphilones from P. sclerotiorum E23Y-1A were tested for their anti-inflammatory and antitumor activities. Penicilazaphilone N (9) showed moderate anti-inflammatory activity with an IC50 value of 22.63 ± 2.95 μM, whereas penidioxolane C (4) exhibited moderate inhibition against human myeloid leukemia cells (K562), human liver cancer cells (BEL-7402), human gastric cancer cells (SGC-7901), human non-small cell lung cancer cells (A549), and human hela cervical cancer cells, with IC50 values of 23.94 ± 0.11, 60.66 ± 0.13, 46.17 ± 0.17, 60.16 ± 0.26, and 59.30 ± 0.60 μM, respectively.
Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis islimited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1–7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment.These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production.
1 June 2020 in European Journal of Plant Pathology
Three new phenolic compounds, epicocconigrones C–D (1–2) and flavimycin C (3), together with six known phenolic compounds: epicocconigrone A (4); 2-(10-formyl-11,13-dihydroxy-12-methoxy-14-methyl)-6,7-dihydroxy-5-methyl-4-benzofurancarboxaldehyde (5); epicoccolide B (6); eleganketal A (7); 1,3-dihydro-5-methoxy-7-methylisobenzofuran (8); and 2,3,4-trihydroxy-6-(hydroxymethyl)-5-methylbenzyl-alcohol (9), were isolated from fermentation cultures of a deep-sea sediment-derived fungus, Aspergillus insulicola. Their planar structures were elucidated based on the 1D and 2D NMR spectra and HRESIMS data. The absolute configurations of compounds 1–3 were determined by ECD calculations. Compound 3 represented a rare fully symmetrical isobenzofuran dimer. All compounds were evaluated for their α-glucosidase inhibitory activity, and compounds 1, 4–7, and 9 exhibited more potent α-glucosidase inhibitory effect with IC50 values ranging from 17.04 to 292.47 μM than positive control acarbose with IC50 value of 822.97 μM, indicating that these phenolic compounds could be promising lead compounds of new hypoglycemic drugs.
Two undescribed p-terphenyl derivatives, asperterphenylcins A–B (1–2), and two undescribed diphenyl ether derivatives, asperdiphenylcins A–B (3–4), together with three previously described p-terphenyl derivatives—4″-deoxyterprenin (5), terphenyllin (6), and 3″-hydroxyterphenyllin (7)—were obtained from the solid-rice culture of the marine-derived fungus Aspergillus candidus HM5-4, which was isolated from sponges from the South China Sea. Their structures were elucidated by HRESIMS data and NMR spectroscopic analysis. Compound 1 showed a strong inhibitory effect on Neoscytalidium dimidiatum, with an inhibition circle diameter of 31.67 ± 2.36 mm at a concentration of 10.0 µg/disc. Compounds 5 and 7 displayed cytotoxic activity against human chronic myeloid leukemia cells (K562), human liver cancer cells (BEL-7402), human gastric cancer cells (SGC-7901), human non-small cell lung cancer cells (A549) and human HeLa cervical cancer cells, with IC50 values ranging from 3.32 to 60.36 µM, respectively. Compounds 2, 6 and 7 showed potent inhibitory activity against α-glucosidase, with IC50 values of 1.26 ± 0.19, 2.16 ± 0.44 and 13.22 ± 0.55 µM, respectively.
Six undescribed capnosane-type macrocyclic diterpenes sarcocrassolins A–F (1–6) and one related known analog pavidolide D (7) were isolated from Sarcophyton crassocaule, a soft coral collected off the Nansha Islands, in the South China Sea. Their complete structures, relative configurations and absolute configurations were established through comprehensive spectroscopic analysis, quantum mechanical nuclear magnetic resonance (QM-NMR) and single-crystal X-ray diffraction. Sarcocrassolins D (4) and E (5) showed inhibitory activity against lipopolysaccharide (LPS)-stimulated inflammatory responses in RAW264.7 cells with IC50 values of 76.8 ± 8.0 μM and 93.0 ± 3.8 μM, respectively.