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Wilt disease caused by Fusarium solani, a soil-borne plant pathogenic fungus, is a serious disease in tomato causing economic losses. In the present study, among the nine isolates of Chaetomium globosum Kunze (Chg1-Chg9), screened against F. solani No. Fs-1, Chg2 exhibited the maximum inhibition (49.2 %), followed by the isolates Chg6 (47.4%) and Chg1 (46.3%) in dual culture. Further, the crude secondary metabolites from these three isolates showed maximum reduction of the mycelial growth of Fs-1 compared to control. Gas Chromatography-Mass Spectrometry (GC-MS) analysis of the metabolites from Chg2 revealed the presence of major compounds, viz., benzothiazole, 2-(2-hydroxyethylthio) (7.51%); 9,12,15- octadecatrienoic acid, 2,3-bis[(trimethylsilyl)oxy] propyl ester (3.13%); and hexadecanoic acid, 1- (hydroxymethyl)-1,2-ethanediyl ester (2.69%). Fourier transform infrared (FTIR) spectroscopy revealed the presence of alcohol, secondary amine, aliphatic primary amine, carboxylic acid, allene, conjugated ketone, imine/oxime, sulphate, and halo compound groups with a weak to strong range of intensity. Pure compound of benzothiazole @ 5000 ppm exhibited higher antagonistic activity of Fs-1which decreased at lower concentration. In pot culture experiment, dipping tomato seedlings cv. PKM1 in 2% ethyl acetate-fractionated biomolecules of Chg2 recorded a minimum disease incidence of 20.0%, whereas seedlings dipped in the culture filtrate of Chg2 showed a disease incidence of 26.6% compared to control (86.6%). Besides, these seedlings treated with the culture filtrate showed the highest plant height of 37.68 cm and the maximum number of leaves and flowers (39.6 and 5.48, respectively), followed by those treated with the biomolecules of Chg2 (C. globosum) and the culture filtrate of T. asperellum. The results revealed that the antifungal efficacy of C. globosum Chg2 is due to the presence of antimicrobial metabolites including benzothiazole. Exploring the use of this novel antifungal compound in the management of plant diseases is highly warranted., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The current study was conducted to evaluate the antiproliferative and oxidative damage protection potential of endophytic fungi Aspergillus fumigatus and Chaetomium globosum isolated from Moringa oleifera. The chloroformic extract (CE) of both the fungi showed dose dependent antiproliferative activity against human prostate adenocarcinoma (PC-3) cell line with (IC 50 ) value of 0.055 mg/ml and 0.008 mg/ml, respectively. Further, CE of both the fungi was studied for their ability to induce apoptosis in PC-3 cell line. Various deformities in the cancerous cells treated with CE of both the fungi have been observed by confocal microscopy which indicates the cell death by apoptosis. Further apoptosis inducing ability of CE of both the fungi was observed using various flow cytometric studies. The chloroformic extract of both the fungi showed slight increase in the level of reactive oxygen species to induce apoptosis. It also showed arrest of cancerous cells at G0/G1 phase of cell cycle to induce apoptosis. The externalization of phosphatidylserine (PS) to induce apoptosis was also observed when analysed using Annexin V-FITC/PI double staining assay where the CE of A. fumigatus and C. globosum showed the total apoptosis of 94.2% and 90.3%, respectively, at the highest tested concentration of GI 70 . The CE of both the fungi further showed the protective behaviour for plasmid DNA pBR322, when tested for their effect against the oxidative stress caused by the Fenton's reagent. Thus, the studies demonstrated a good antiproliferative and oxidative damage protection potential of the endophytic fungi., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A novel β-1,3-glucanase gene, designated Ccglu17A, was cloned from the biological control fungus Chaetomium cupreum Ame. Its 1626-bp open reading frame encoded 541 amino acids. The corresponding amino acid sequence showed highest identity (67 %) with a glycoside hydrolase family 17 β-1,3-glucanase from Chaetomium globosum. The recombinant protein Ccglu17A was successfully expressed in Pichia pastoris, and the enzyme was purified to homogeneity with 10.1-fold purification and 47.8 % recovery yield. The protein's molecular mass was approximately 65 kDa, and its maximum activity appeared at pH 5.0 and temperature 45 °C. Heavy metal ions Fe 2+ , Mn 2+ , Cu 2+ , Co 2+ , Ag + , and Hg 2+ had inhibitory effects on Ccglu17A, but Ba 2+ promoted the enzyme's activity. Ccglu17A exhibited high substrate specificity, almost exclusively catalyzing β-1,3-glycosidic bond cleavage in various polysaccharoses to liberate glucose. The enzyme had a Km of 2.84 mg/mL and Vmax of 10.7 μmol glucose/min/mg protein for laminarin degradation under optimal conditions. Ccglu17A was an exoglucanase with transglycosylation activity based on its hydrolytic properties. It showed potential antifungal activity with a degradative effect on cell walls and inhibitory action against the germination of pathogenic fungus. In conclusion, Ccglu17A is the first functional exo-1,3-β-glucanase to be identified from C. cupreum and has potential applicability in industry and agriculture.

Among forty endophytic fungal isolates derived from the mangrove plant Avicennia marina, thirty-seven isolates (92.5 %) shown vary antimycotic activity against clinical Trichophyton, Microsporum, and Epidermophyton isolates. The hyperactive wild antagonistic strains Acremonium sp. MERV1 and Chaetomium sp. MERV7 were subjected to intergeneric protoplast fusion technique, and out of 20 fusants obtained, the fusant MERV6270 showed the highest antimycotic activity with the broadest spectrum against all dermatophytes under study. Solid-state fermentation (SSF) showed its superiority for antimycotic/antiviral metabolite production using cost-effective agroindustrial residues. Low-cost novel fermentation medium containing inexpensive substrate mixture of molokhia stalk, lemon peel, pomegranate peel, peanut peel (2:1:1:1) moistened with potato, and meat processing wastewaters (2:1, at moisture content of 60 %) provided a high antimycotic metabolite yield, 33.25 mg/gds, by the fusant MERV6270. The optimal parameters for antimycotic productivity under SSF were incubation period (4 days), incubation temperature (27.5-30 °C), initial pH (6), initial moisture level (60 %), substrate particle size (1.0 mm), and inoculum size (2 × 10(6) spores/gds), which elucidated antimycotic activity to 44.19 mg/gds. Interestingly, wild mangrove Acremonium sp. MERV1 and Chaetomium sp. MERV7 strains and their fusant MERV6270 showed significant inhibition of hepatitis C virus with viral knockdown percent of -82.48, -82.44, and -97.37 %, respectively, compared to the control (100 %), which open a new era in combat epidemic viral diseases.