Phytotoxic and Antibacterial Metabolites from Fusarium proliferatum ZS07 Isolated from the Gut of Long-horned Grasshoppers

Abstract

In the proceeding of screening new bioactive natural products, the ethyl acetate extract of the fermentation broth of Fusarium proliferatum ZS07, a fungus residing in the gut of long-horned grasshoppers (Tettigonia chinensis), was found possessing selective phytotoxic activity against the radicle growth of Amaranthus retroflexus L. Bioactivity-guided fractionation lead to the isolation of six fungal metabolites 1-6, including a new polyketide derivate O-methylated SMA93 (2) and five known compounds SMA93 (1), rhodolamprometrin (3), radicinin (4), dehydroallogibberic acid (5), and 3-methyl-6,8-dihydroxyisocoumarin (6). Their structures were identified on the basis of spectroscopic analysis and by comparison of the corresponding data to those reported in the literature previously. Phytotoxic effects of the four isolated compounds 1-4 on the radicle growth of A. retroflexus L. seeds were investigated under laboratory conditions, and compounds 2 and 4 showed good phytotoxic activity in the concentration of 100 μg/mL, with the inhibition rates of 83.0 and 65.2%, respectively. Furthermore, the antibacterial activity of compounds 1-5 were evaluated against selected bacteria. Compounds 1-3 were found to possess potent antibacterial activity against Bacillus subtilis (ATCC 6633), with the minimum inhibitory concentration (MIC) values of 3.13-12.50 μg/mL, while Escherichia coli (ATCC 8739) and Salmonella typhimurium [CMCC(B) 50115] were not susceptible. These results suggest that the new polyketide derivate 2 and known compounds 1, 3, and 4 have potential to be used as biocontrol agents in agriculture.

Phytotoxic and Antifungal Metabolites from Curvularia crepinii QTYC-1 Isolated from the Gut of Pantala flavescens

“…The strain was isolated based on methods described previously [ 21 ]. P. flavescens were collected from the suburb of Jinhua, Zhejiang Province, PR China during the growing season.…”

Diversity, Bacterial Symbionts and Antibacterial Potential of Gut-Associated Fungi Isolated from the Pantala flavescens Larvae in China

“…Surface sterilization and isolation of symbiotic fungi were accomplished by following our previously established procedures [ 23 ]. Briefly, the samples were promptly transported to the laboratory and starved for 24 h. Prior to dissection, the larvae of P .…”

Isolation, identification, derivatization and phytotoxic activity of secondary metabolites produced by Cladosporium oxysporum DH14, a locust-associated fungus

“…Daldinia eschscholzii associated with mantis (Zhang et al 2011b), and a number of compounds with biological activity derived from fungus residing in the gut of insect (Zhang et al 2011a;Li et al 2014). During our ongoing efforts to find new biological active metabolites from the insect gut microbial (Zhang et al 2008a), we found that the ethyl acetate extract from the fermentation broth of the fungus strain DH14, isolated from the gut of locust, exhibited strongly phytotoxic activity against the radicle growth of Amaranthus retroflexus L. We herein described the isolation, structural [键入文字] 3 elucidation, dramatization and phytotoxic activity of secondary metabolites produced by the strain DH14.…”

“…The phytotoxic effects of ethyl acetate extract of DH14 were evaluated on radicle growth of E. crusgalli L. and A. retroflexus L. under the concentration of 100 μg mL -1 , along with selected crops (B. rapa L., S. durra, B. campestris L., C. annucm and R. sativus L.) to evaluate the bio-security on [键入文字] 7 the base of petri dish bioassay (Silva et al 2012). The bioassay was performed at 25°C (Li et al 2014) with 2,4-D used as a positive control. All experiments were performed in triplicate and data were showed as mean values±standard deviation.…”