Two phytotoxic azaphilone derivatives fromChaetomium globosum, a fungal endophyte isolated fromAmaranthus viridisleaves

Abstract

A fungal endophyte isolated from the leaves of the allelopathic plant Amaranthus viridis of the family Amaranthaceae was identified as Chaetomium globosum through molecular means using internal transcribed spacer (ITS) region of rDNA gene. This is the first report of the isolation of C. globosum from Amaranthaceae. Chromatographic separation of the EtOAc extract of the fungal fermentation in potato dextrose broth yielded two known chlorine-containing azaphilone derivatives, chaetomugilin D (1) and chaetomugilin J (2). Compounds 1 and 2 were found to show phytotoxic activity in the lettuce (Lactuca sativa) seed germination bioassay. The IC50 values of 1 and 2 for root growth inhibition were 24.2 and 22.6 ppm, respectively, while IC50 values for shoot growth inhibition were 27.8 and 21.9 ppm, respectively. Phytotoxic activities of the chaetomugilin group of compounds have been reported for the first time, although their antifungal, antimicrobial and cytotoxic activities are known.

Bioactive sesquiterpenes from an endophytic fungus Bipolaris sorokiniana isolated from a popular medicinal plant Costus speciosus

“…Both EtOAc extracts were found to show a similar TLC pattern. The combined EtOAc extract was screened for antifungal activity against C. cladosporioides using the TLC bioautography method (Homans and Fuchs 1970), antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (Alakolanga et al 2015), brine shrimp lethality (Howlader et al 2006), phytotoxicity against lettuce seed germination (Piyasena et al 2015) and αamylase enzyme inhibitory bioassays (Nickavar et al 2008). Repeated chromatographic separation of the EtOAc extract over silica gel (hexane-EtOAc), Sephadex LH-20 (30% CHCl 3 -MeOH) and final separation by PTLC (developed with hexane-EtOAc, 4:1 for 1 and 3:2 for 2) furnished helminthosporal acid (1, 26 mg), helminthosporol (2, 30 mg) and ergosterol (115 mg).…”

Antibacterial Activity of Austdiol Isolated from Mycoleptodiscus indicus Against Xanthomonas axonopodis pv. Passiflorae

“…21 For example of azaphilones obtained from endophytic fungi with phytotoxic activity able to be cited the azaphilones chaetomugilin D and chaetomugilin J isolated from Chaetomium globasum, a endophytic from leaves of the Amaranthus viridis. 22 For the azaphilone austdiol isolated in the present work was described cytotoxic activity against tumor cells and leishmanicidal activity on Leishmania major and L. dovani. 15 However, there are no studies on its activity against agricultural pests such as the bacterial blight of passion fruit, this being the first report of this important activity for the austdiol, which can open the possibility of production of a new antibacterial agent for the control of X. axonopodis pv.…”

Formation and Functioning of Chaetomium Cochliodes / Fagopyrum Еsculentum Endophytic Association

“…A large number of the Chaetomium metabolism biologically active products are known. Micromycete C. atrobrunneum L. M. Ames produces fungicides fuscoatroside and heteatrosine (Hwangatal., 2000;Kobayashi et al, 2005), C. cochliodes Palliserantibiotic hetamine (Geigeretal., 1944), C. globosum Kunse -phytotoxinazophilone and hematomohiline D and J, antibiotics Hetamine and Hetirovidine (Piyasena et al, 2015). C. gracile Udagawa is an antimicrobial hetochromin A (Bai et al, 2015).…”