Bioactive metabolites from Alternaria brassicicola ML-P08, an endophytic fungus residing in Malus halliana

Abstract

A total of 48 strains were isolated from the normal tissues of Malus halliana and the EtOAc extracts of their cultures were subjected to primary antimicrobial screening against four test bacteria and three fungi. As a result, 22 strains exhibited antimicrobial activity against at least one test microbe. Among them, Alternaria brassicicola ML-P08 showing strong activity (MICs: 0.31-2.50 mg/ml) was selected for further investigation on its secondary metabolites. Bioassay-guided fractionation of the EtOAc extract of its liquid culture afforded seven compounds, which were identified as alternariol (

Natural Dibenzo-α-Pyrones and Their Bioactivities

“…Alternaria alternata [21] Unidentified freshwater fungus belong to Tubeufiaceae [19] Malus halliana [28] Endophytic Alternaria tenuissima EN-192 isolated from Rhizophora stylosa [29] Endophytic Colletotrichum sp. isolated from Aristolochia sp.…”

“…PR-14 isolated from Paeonia delavayi [24] Endophytic Alternaria sp. isolated from Datura stramonium [25] Malus halliana [28] Endophytic Alternaria linicola isolated from Linum ustiatissimum [32] Alternaria tenuis [33] …”

“…Among Alternaria dibenzo-α-pyrones, alternariol (10) was the most active metabolite to have cytotoxic activity on L5178Y mouse lymphoma cells [9], as well as to have inhibitory activity on protein kinase and xanthine oxidase [28]. Further investigation showed that alternariol (10) was a topoisomerase I and II poison which might contribute to the impairment of DNA integrity in human colon carcinoma cells [73,76].…”

One Strain-Many Compounds Method for Production of Polyketide Metabolites Using the Sponge-Derived Fungus Arthrinium arundinis ZSDS1-F3

“…Detailed chemical investigation resulted in the isolation of a new natural product, phenethyl 5-hydroxy-4-oxohexanoate (1), which had been previously obtained by natural product biosynthesis [10] (4) [11], decarboxycitrinone (5) [12], and altechromone A (6) [13]. Their cytotoxic activities against the K562, MCF-7, HeLa, DU145, U937, H1975, SGC-7901, A549, MOLT-4, and HL60 cell lines were examined.…”

“…However, two carbon signals showed very high intensities at G C 129.4 and 129. 13 C NMR spectrum. From detailed investigation of the data from 1 H-1 H COSY, HMQC, and HMBC experiments, we were able to develop the structure of the linear part from C-7 through C-14.…”