Milan K. Pal

Bio: Milan K. Pal is an academic researcher from University of Calcutta. The author has contributed to research in topics: Anaphalis & Amide. The author has an hindex of 2, co-authored 2 publications receiving 17 citations.

Bioactive Phenylalanine Derivatives and Cytochalasins from the Soft Coral-Derived Fungus, Aspergillus elegans

Abstract: One new phenylalanine derivative 4′-OMe-asperphenamate (1), along with one known phenylalanine derivative (2) and two new cytochalasins, aspochalasin A1 (3) and cytochalasin Z24 (4), as well as eight known cytochalasin analogues (5–12) were isolated from the fermentation broth of Aspergillus elegans ZJ-2008010, a fungus obtained from a soft coral Sarcophyton sp. collected from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods. The absolute configuration of 1 was determined by chemical synthesis and Marfey’s method. All isolated metabolites (1–12) were evaluated for their antifouling and antibacterial activities. Cytochalasins 5, 6, 8 and 9 showed strong antifouling activity against the larval settlement of the barnacle Balanus amphitrite, with the EC50 values ranging from 6.2 to 37 μM. This is the first report of antifouling activity for this class of metabolites. Additionally, 8 exhibited a broad spectrum of antibacterial activity, especially against four pathogenic bacteria Staphylococcus albus, S. aureus, Escherichia coli and Bacillus cereus.

Two new Penicillium species Penicillium buchwaldii and Penicillium spathulatum, producing the anticancer compound asperphenamate.

Abstract: Penicillium buchwaldii sp. nov. (type strain CBS 117181T = IBT 6005T = IMI 30428T) and Penicillium spathulatum sp. nov. (CBS 117192T = IBT 22220T) are described as new species based on a polyphasic taxonomic approach. Isolates of P. buchwaldii typically have terverticillate conidiophores with echinulate thick-walled conidia and produce the extrolites asperphenamate, citreoisocoumarin, communesin A and B, asperentin and 5′-hydroxy-asperentin. Penicillium spathulatum is unique in having restricted colonies on Czapek yeast agar (CYA) with an olive grey reverse, good growth on CYA supplemented with 5% NaCl, terverticillate bi- and ter-ramulate conidiophores and consistently produces the extrolites benzomalvin A and D and asperphenamate. The two new species belong to Penicillium section Brevicompacta and are phylogenetically closely related to Penicillium tularense. With exception of Penicillium fennelliae, asperphenamate is also produced by all other species in section Brevicompacta (P. tularense, Penicillium brevicompactum, Penicillium bialowiezense, Penicillium olsonii, Penicillium astrolabium and Penicillium neocrassum). Both new species have a worldwide distribution. The new species were mainly isolated from indoor environments and food and feedstuffs. The fact that asperphenamate has been found in many widely different plants may indicate that endophytic fungi rather than the plants are the actual producers. © 2012 Federation of European Microbiological Societies.