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Natural pigments derived from microorganisms have many advantages and are widely studied in the food industry. A filamentous fungus, DBFL05, was identified as Aspergillus ustus, which produces a bright and abundant brown pigment. This extracellular, water-soluble pigment is highly polar and slightly soluble in alcohol but insoluble in other organic solvents. The pigment is stable under sunlight, at pH 2–10, and below 100°C. However, it is sensitive to Zn2+, Fe3+, Fe2+, and Cu2+. The pigment is mainly composed of two chemical components, pyrropyrazine diketone and dianthrone, and is classified as a polyketone pigment. Both components of the pigment exhibit inhibitory effects on bacteria and scavenging abilities for •OH and DPPH. The pigment showed no significant toxicity to plants and low toxicity to brine shrimp larvae. These findings indicate that the easily obtainable A. ustus pigment is a polyketone with attractive colour, stability, safety, and bioactivity. [ABSTRACT FROM AUTHOR]

A new austin-type meroterpene, namely, ustusaustin A (1), together with seven related known analogues (2–8), were isolated and identified from the culture extract of Aspergillus ustus TK-5, an endophytic fungus obtained from the marine ascidian Pyura momus. The structures of these compounds were established on the basis of detailed interpretation of their NMR and MS data, and the relative and absolute configurations of 1 was confirmed by X-ray crystallographic analysis. Among them, ustusaustin A (1) represents the first example of 1'-nor-austin analogues with an unique 7-benzoylation. Compounds 1–4, 6, and 7 exhibited potent neuraminidase inhibitory activity and this is the first report of neuraminidase inhibitory activity for austin-type meroterpenes. [ABSTRACT FROM AUTHOR]

One new dihydrobenzofuran derivative (1), known depsipeptide emericellamide A (2), three known drimanes (3–5) and two artifact drimane derivatives (6, 7) were isolated from the marine-derived fungus Aspergillus ustus KMM 4664. Their structures were determined by detailed analysis of spectroscopic data and by comparison with related known compounds. The absolute configuration of 1 was determined by time-dependent density functional theory (TD-DFT) calculations of ECD spectra. Compound 7 showed significant ability of the inhibition of spermatozoa to fertilize egg-cells of the sea urchin Strongylocentrotus intermedius with IC50 value 21 µM. [ABSTRACT FROM AUTHOR]

Aspergillus ustusis among the most ubiquitous soil species and has been implicated in human infections. The complete mitochondrial genome ofA. ustushas been determined by high-throughput sequencing technology in this work. Our study revealed that the mitochondrial genome ofA. ustusis 33,007 bp long, with AT content of 74.84%, which consists of a usual set of mitochondrial proteins and RNA genes, including large and small ribosomal RNAs, 15 proteins and 20 tRNA genes and contains two introns. Notably, it also contains three hypothetical proteins without obvious homology to any known proteins. All structural genes are located on one strand and are apparently transcribed in one direction. The complete mitochondrial genomes ofA. ustuswould be useful for future investigation of the genetics, evolution and clinical identification ofAspergillusspecies. [ABSTRACT FROM AUTHOR]