The genus Dalbergia contains approximately 250 species with many valuable trees being destroyed by targeted and illegal logging. DNA barcoding is a reliable method for the molecular identification of different species and resources conservation. In the present study, the specimen discrimination ability of internal transcribed spacer (ITS), matK, rbcL and psbA-trnH barcoding were tested on Dalbergia sequences, downloaded from the National Center for Biotechnology Information (NCBI), and the combined barcoding ITS+matK+rbcL was used to identify unknown specimens. It was found that ITS+matK+rbcL have good discrimination rates based on the analysis methods best match (BM) and best close match (BCM). These barcodes also have the best performance concerning barcode gap distribution, and are able to discriminate unknown specimens from South-China. Furthermore, it was demonstrated that D. tamarindifolia and D. rubiginosa are also relatively close to sister-species D. pinnata and D. candenatensis within the phylogenetic Dalbergia tree. Considering the overall performance of these barcodes, we suggest that the ITS+matK+rbcL region is a suitable barcode for identifying Dalbergia species.
Phomeroids A (1) and B (2), two novel meroterpenoids representing two types of skeletons, together with one known homologous analogue (3) were isolated from the deep-sea-derived fungus Phomopsis tersa FS441. Phomeroid A is the first example of tropolonic sesquiterpenes consisting of a highly fused 6/6/11/6/5/5 ring system, while phomeroid B is the first example of meroterpenoids featuring an unusual 7/6/11/6-5 spiral core skeleton. All of them showed considerable cytotoxicity against the tested cell lines, and their biosynthetic pathways were also discussed.
Four phenylfuropyridone racemates, (±)-tersones A-C and E (1–3, 5), one phenylpyridone racemate, (±)-tersone D (4), one new pyridine alkaloid, tersone F (6), single new phenylfuropyridone, tersone G (7) and two known analogs 8 and 9 were isolated from the deep-sea fungus Phomopsis tersa. Their structures and absolute configurations were characterized on the basis of comprehensive spectroscopic analyses, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) calculations. Moreover, compounds 1–9 were evaluated for in vitro antimicrobial and cytotoxic activity. Compounds 5b and 8b exhibited antibacterial activity against S. aureus with the MIC value of 31.5 μg/mL, while compound 5b showed cytoxic activities against SF-268, MCF-7, HepG-2 and A549 cell lines with IC50 values of 32.0, 29.5, 39.5 and 33.2 μM, respectively.
The pre-aerobic process of coking wastewater treatment has strong capacity of decarbonization and detoxification, which contribute to the subsequent dinitrogen of non-carbon source/heterotrophic denitrification. The COD removal rate can reach > 90% in the first aerobic bioreactor of the novel O/H/O coking wastewater treatment system during long-term operation. The physico-chemical characteristics of influent and effluent coking wastewater in the first aerobic bioreactor were analyzed to examine how they correlated with bacterial communities. The diversity of the activated sludge microbial community was investigated using a culture-independent molecular approach. The microbial community functional profiling and detailed pathways were predicted from the 16S rRNA gene-sequencing data by the PICRUSt software and the KEGG database. High-throughput MiSeq sequencing results revealed a distinct microbial composition in the activated sludge of the first aerobic bioreactor of the O/H/O system. Proteobacteria, Bacteroidetes, and Chlorobi were the decarbonization and detoxification dominant phyla with the relative abundance of 84.07 ± 5.45, 10.89 ± 6.31, and 2.96 ± 1.12%, respectively. Thiobacillus, Rhodoplanes, Lysobacter, and Leucobacter were the potential major genera involved in the crucial functional pathways related to the degradation of phenols, cyanide, benzoate, and naphthalene. These results indicated that the comprehensive understanding of the structure and function diversity of the microbial community in the bioreactor will be conducive to the optimal coking wastewater treatment.
9 January 2020 in Organic & Biomolecular Chemistry
Photeroids A (1) and B (2), two structurally fascinating meroterpenoids, were isolated from the deep-sea-derived fungus Phomopsis tersa FS441. Their structures were sufficiently established by a comprehensive interpretation of the spectroscopic data, NMR spectra, and ECD calculation. Photeroids A and B represented the first phenolic sesquiterpene meroterpenoids featuring a highly fused 6/6/6/6 tetracyclic ring system derived through a rarely-occurring hetero-Diels–Alder reaction via an orthoquinone methide intermediate. Additionally, they were also evaluated for their cytotoxic activities against four human cancer cells, wherein compounds 1 and 2 exhibited moderate cytotoxic activities.