Search Results (5)

Memnoniella is a fungal genus from which a wide range of diverse biologically active compounds have been isolated. A Memnoniella dichroa CF-080171 extract was identified to exhibit potent activity against Plasmodium falciparum 3D7 and Trypanosoma cruzi Tulahuen whole parasites in a high-throughput screening (HTS) campaign of microbial extracts from the Fundación MEDINA’s collection. Bioassay-guided isolation of the active metabolites from this extract afforded eight new meroterpenoids of varying potencies, namely, memnobotrins C-E (1–3), a glycosylated isobenzofuranone (4), a tricyclic isobenzofuranone (5), a tetracyclic benzopyrane (6), a tetracyclic isobenzofuranone (7), and a pentacyclic isobenzofuranone (8). The structures of the isolated compounds were established by (+)-ESI-TOF high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Compounds 1, 2, and 4 exhibited potent antiparasitic activity against P. falciparum 3D7 (EC₅₀ 0.04–0.243 μM) and T. cruzi Tulahuen (EC₅₀ 0.266–1.37 μM) parasites, as well as cytotoxic activity against HepG2 tumoral liver cells (EC₅₀ 1.20–4.84 μM). The remaining compounds (3, 5–8) showed moderate or no activity against the above-mentioned parasites and cells. Full article

Anthracnose, caused by fungi of the genus Colletotrichum, is present in the main areas where rubber trees (Hevea brasiliensis) are planted. Thus, considering that biological agents can be an alternative for disease control, the present study aimed to carry out initial studies to investigate the response of rubber tree seedlings inoculated with Colletotrichum and treated with saprobes fungi from the semiarid region of Northeast Brazil (Curvularia eragrostidis, Memnoniella levispora, Myrothecium roridum and Phialomyces macrosporus). Seedlings of the rubber tree clone RRIM600 were sprayed with biocontrol agents as preventive and curative treatments seven days before and after C. tamarilloi inoculation, respectively. Assessments included plant response to disease expression based on the percentage of symptomatic area on treated leaves, percentage of graft death, and percentage of apical death in seedlings 30 days after inoculation with C. tamarilloi. In addition, the enzymes peroxidase and phenylalanine ammonia lyase (PAL) had their activity quantified by their association with plant resistance to pathogens. The fungus C. eragrostidis had the best result in controlling anthracnose when applied as a preventive treatment, showing 10% less disease than the untreated plant. The same was observed for the fungus P. macrosporus when used in the curative form. These fungi also reduced the graft death. In these cases, PAL activity was higher and may be linked to the induction of resistance against the pathogen. The peroxidase activity was not expressive for treatments with saprobic fungi in the periods studied. Therefore, among the tested fungi, C. eragrostidis and P. macrosporus are promising for the control of anthracnose, deserving further studies. Full article

Stachybotrys chartarum is one of the world’s ten most feared fungi within the family Stachybotryaceae, although to date, not a single mitogenome has been documented for Stachybotryaceae. Herein, six mitogenomes of four different species in Stachybotryaceae are newly reported. The S. chartarum mitogenome was 30.7 kb in length and contained two introns (one each in rnl and cox1). A comparison of the mitogenomes of three different individuals of S. chartarum showed few nucleotide variations and conservation of gene content/order and intron insertion. A comparison of the mitogenomes of four different Stachybotryaceae species (Memnoniella echinata, Myrothecium inundatum, S. chartarum, and S. chlorohalonata), however, revealed variations in intron insertion, gene order/content, and nad2/nad3 joining pattern. Further investigations on all Hypocreales species with available mitogenomes showed greater variabilities in gene order (six patterns) and nad2/nad3 joining pattern (five patterns) although a dominant pattern always existed in each case. Ancestral state estimation showed that in each case the dominant pattern was always more ancestral than those rare patterns. Phylogenetic analyses based on mitochondrion-encoded genes supported the placement of Stachybotryaceae in Hypocreales. The crown age of Stachybotryaceae was estimated to be approximately the Early Cretaceous (141–142 Mya). This study greatly promotes our understanding of the evolution of fungal species in Hypocreales. Full article

A study was conducted to investigate saprobic fungal niches of Stachybotryaceae (Hypocreales) associated with leaves of Musa (banana) in China and Thailand. Three hyphomycetous taxa were collected during the dry season of 2018 and 2019. After a careful phenotypic characterization (both macro- and microscopically) and a phylogenetic tree reconstruction using a concatenated sequence dataset of internal transcribed spacer (ITS), calmodulin (cmdA), RNA polymerase II second largest subunit (rpb2), β-tubulin (tub2), and the translation elongation factor 1-alpha (tef1) gene regions, we report three species of Stachybotryaceae. Stachybotrys musae is introduced as a novel taxon from Yunnan, China, while S.microsporus is reported from Chiang Rai Province in Thailand on Musa. In addition, Memnoniella levispora is also reported from China for the first time. Full article

Fumonisins are phytotoxic mycotoxins which are synthesized by various species of the fungal genus Fusarium such as Fusarium verticillioides (Sacc.) Nirenberg (ex F.moniliforme Sheldon) and Fusarium proliferatum. The trichothecene (TC) mycotoxins are secondary metabolites produce by species that belong to several fungal genera, especially Fusarium, Stachybotrys, Trichothecium, Trichoderma, Memnoniella and Myrothecium. Fusarium mycotoxins are widely dispersed in cereals and their products. Zearalenone (ZEA) is an estrogenic compound produced by Fusarium spp. such as F. graminearum and F. culmorum. Fumonisins, the TCs and ZEA are hazardous for human and animal health. Contamination with TCs causes a number of illnesses in human and animal such as decrease in food consumption (anorexia), depression or inhibition on immune system function and haematoxicity. The purpose of this paper is to give a review of the papers published on the field of fumonisin, TC and ZEA mycotoxins in cereals consumed in the world. Full article