Four butyrolactones and diverse bioactive secondary metabolites from terrestrial Aspergillus flavipes MM2: isolation and structure determination

Abstract

The chemical constituents and biological activities of the terrestrial Aspergillus flavipes MM2 isolated from Egyptian rice hulls are reported. Seven bioactive compounds were obtained, of which one sterol: ergosterol (1), four butyrolactones: butyrolactone I (2), aspulvinone H (3), butyrolactone-V (6) and 4,4'-diydroxypulvinone (7), along with 6-methylsalicylic acid (4) and the cyclopentenone analogue; terrien (5). Structures of the isolated compounds were deduced by intensive studies of their 1D & 2D NMR, MS data and comparison with related structures. The strain extract and the isolated compounds (1-7) were biologically studied against number of microbial strains, and brine shrimp for cytotoxicity. In this article, the taxonomical characterization of A. flavipes MM2 along with its upscale fermentation, isolation and structural assignment of the obtained bioactive metabolites, and evaluate their antimicrobial and cytotoxic activities were described.

Derivatives of Holomycin and Cyclopropaneacetic Acid from Streptomyces sp. DT‐A37

“…Inspection of the 1D-and 2D-NMR data revealed that it had similar structure to that of compound 4 except an additional methine group d(H) 3.38 (H-C(5″)), d(C) 72.5 (C(5″)). 1 Fig. 4) indicated that the methine group was located at C(5″).…”

“…In recent decades, numerous bioactive natural products have been isolated from strains of bacteria collected from different environments such as plants, animals, soils and sediments. [1] Among these bacteria, members of the order Actinomycetales play the most important roles in the production of secondary metabolites. [2] This order produce about 75% original scaffolds of marketed antibiotics, among which the genus Streptomyces stands out as the best explored.…”

Antibacterial Metabolites from the Sri Lankan Demosponge-Derived Fungus, <i>Aspergillus flavipes</i>

“…The fungi isolated in the current study could be either obligatory or facultative 'marine fungi', hence other than using the term marine fungi, referring to them as marine/sponge-derived fungi is more appropriate as we have not determined the origin. A. flavipes has been reported from both terrestrial and marine sources [20][21][22][23] . Therefore, whether A. flavipes isolated in this study is a facultative marine fungus, that has been accumulated through filter feeding or an obligatory marine fungus, which has originated in the internal tissues, is open to conjecture.…”

Mass Spectrometric Characteristics of Prenylated Indole Derivatives from Marine-Derived Penicillium sp. NH-SL

“…In recent years, numerous biologically active natural products have been isolated from microbes collected from different environments such as plants, animals, soils, and sediments [3]. Marine microbes have been proven to possess a unique metabolic mechanism and an adaptive mechanism due to their special living environment, which is quite different from a terrestrial environment specialized in high pressure, high salt, low temperature, and a lack of nutrition [4].…”