Secondary Metabolites from Aspergillus sparsus NBERC_28952 and Their Herbicidal Activities

Abstract

Fungi have been used in the production of a wide range of biologically active metabolites, including potent herbicides. In the search for pesticides of natural origin, Aspergillus sparsus NBERC_28952, a fungal strain with herbicidal activity, was obtained. Chemical study of secondary metabolites from NBERC_28952 resulted in the isolation of three new asperugin analogues, named Aspersparin A–C (2–4), and a new azaphilone derivative, named Aspersparin D (5), together with two known compounds, Asperugin B (1) and sydonic acid (6). The structures of these compounds were elucidated based on extensive spectroscopic data and single-crystal X-ray diffraction analysis. All of the isolated compounds were evaluated for their herbicidal activities on seedlings of Echinochloa crusgalli and Amaranthus retroflexus through Petri dish bioassays. Among them, compounds 5 and 6 exhibited moderate inhibitory activities against the growth of the roots and shoots of E. crusgalli seedlings in a dose-dependent manner, while 6 showed obvious inhibitory effect on seedlings of A. retroflexus, with an inhibitory rate of 78.34% at a concentration of 200 μg/mL. These herbicidal metabolites represent a new source of compounds to control weeds.

A novel method for the extraction and characterization of metabolites from Basidiomycota: Pleurotus ostreatus (Jacq.) P. Kumm., 1871 as a case study

“…Indeed, the extraction of primary and secondary metabolites from a mushroom may prove difficult, depending on many factors. Over the years, numerous protocols have been tried and tested, but for our objectives, aiming at a metabolomic analysis, for several reasons they have proved unsatisfactory: i) usual protocols are aimed at extracting metabolites produced by microorganisms cultivated on a petri dish [17,18]; ii) usual protocols perform the total extraction of metabolites produced by anamorphic fungi or yeasts that have less interference problems related to the presence of structural polysaccharides and their derivates, such as chitin, respect to macrofungi [17,19,20], and iii) the majority of protocols have been developed to extract a specific class of molecules, thus losing sight of all the other compounds produced by that particular fungal species [21].…”

Isolation, Characterization, and Herbicidal Activity of Streptomyces spp. from Diseased Potato Scab Tubers

“…The strains were grown in 150 mL G1 liquid medium in 250 mL Erlenmeyer ask at 28 ℃, 180 rpm for 7 days. The fermentation broth of cultures was obtained by ltering through cotton gauze, and screened for potential herbicidal activity against two monocotyledonous weeds, E. crusgalli and D. sanguinalis, and a dicotyledonous weed, A. theophrasti by the method described in the previous literature [25]. 30 pregerminated seeds with consistent status were selected to place in Petri dishes (9 cm diameter) with lter paper, and lled with 5 ml of Actinomyces fermentation broth.…”

Nature-Based Herbicides and Micro-/Nanotechnology Fostering Sustainable Agriculture

“…71 are well-studied for bioherbicide development. Among fungi, the most studied are Trichoderma ssp, 72−74 Aspergillus ssp, 75 Fusarium ssp, 76−78 and Phoma ssp. 66,79,80 Although many microorganisms demonstrate herbicidal activity, we must address some limitations to help improve their applications in agriculture.…”

“…are well-studied for bioherbicide development. Among fungi, the most studied are Trichoderma ssp, − Aspergillus ssp, Fusarium ssp, − and Phoma ssp. ,, Table lists the different bioherbicides prepared using microbial culture filtrates against various weeds.…”