Two new aromatic polyketides from a sponge-derived Fusarium

Abstract

In our natural product screening program from marine fungi, two new aromatic polyketides karimunones A (1) and B (2) and five known compounds (3–7) were isolated from sponge-associated Fusarium sp. KJMT.FP.4.3 which was collected from an Indonesian sponge Xestospongia sp. The structures of these compounds were determined by the analysis of NMR and MS spectroscopic data. The NMR assignment of 1 was assisted by DFT-based theoretical chemical shift calculation. Compound 2 showed antibacterial activity against multidrug resistant Salmonella enterica ser. Typhi with a MIC of 125 µg/mL while 1 was not active.

Antioxidant and antimicrobial screening of an unidentified yellow pigmented marine-derived fungus

“…According to Trianto et al [31], this diameter of inhibition zone is categorized as weak activity. Although several records stated pigments from marine fungi had a strong antimicrobial activity [4][5][6], our study got a reverse result. It is north worthy to be considered that all pathogens in this study were clinical isolates and noted as multidrug-resistant organisms (MDRO).…”

“…In addition, a red-pigmented fungi exhibit antibacterial activity against several multidrug-resistant (MDR) bacteria [4]. Sibero et al [5] also stated that sponge-associated fungi produce antimicrobial substances, which is a pigmented fungus from sponge-derived Fusarium [6].…”

A critical review on the use of DP4+ in the structural elucidation of natural products: the good, the bad and the ugly. A practical guide

“…For example, DP4+ allowed to establish the substitution pattern of the aromatic frames in compounds 18-21. 29,104,111,214 Another interesting study was conducted with compound 16 as case study, in which the DP4+ calculations were done to examine the C1-C2 0 and the C1-C3 0 linkage in two regioisomers, further supporting the connection of the xanthone to the ribose via C1-C2 0 . 146 The elucidation of compounds 17, 212 When the connectivity or regiochemistry of chiral molecules is unsure, a lack of certainty in the congurational analysis might be expected as well (e.g.…”

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“…Spot identification using the value of R f (Retention Factor) and spraying with staining reagents. After the elution process, TLC was visualized by UV light (365 nm), 2% vanillin-H 2 SO 4 , 0.25% ninhydrin in acetone, and 1% ferric (III) chloride in methanol (Harborne, 1984;Sen et al, 2012;Trianto et al, 2019). Furthermore, the TLC plate was heated at 110 o C for 2-3 minutes.…”