Concentration of metabolites from Phoma sp. using microfiltration membrane for increasing bioherbicidal activity

Abstract

This study is focused on the concentration of fermented broth from Phoma sp. to increase its herbicidal activity. For this purpose, biomolecules produced by submerged fermentation using Phoma sp. were concentrated by hollow fiber microfiltration membranes. The membrane feed was separated into two streams (retentate and permeate) and the crude broth was concentrated to 10, 30, 50, 70 and 90% (relative to the initial volume). The retentate samples were submitted to bioassays (triplicate) for evaluating their phytotoxic effects on five young leaves of species of Cucumis sativus and also on pre-emergence of weeds as Bidens pilosa and Amaranthus retroflexus. The highest herbicidal activity was 80.7% obtained for a concentration of 30% in the retentate fraction. At this condition, the bioherbicide presented severe damage symptoms on the detached leaves of Cucumis sativus if compared to the crude fermented broth. In the pre-emergence of B. pilosa and A. retroflexus, 100% control was obtained for assays performed in a germination chamber. For greenhouse assays using the substrate, the control rate of A. retroflexus was dependent of concentration of bioherbicide. The promising results achieved in the research with membrane separation process allow us to propose and develop further studies for evaluating this technology in the concentration of other metabolites produced by fermentation which also have bioherbicidal activity.

Evaluation of the herbicidal potential of some fungal species against Bidens pilosa, the coffee farming weeds

“…The results of the laboratory bioassays indicate that the herbicidal constituents present in these fungi are highly effective against the target weed and significantly reduced seed germination as well as early growth of the tested weed in a concentration-dependent manner. This finding is in agreement with those found by ( Todero et al, 2019 ), where the metabolites from Phoma spp showed an inhibitory effect on the germination of B. pilosa seeds. Similarly, the bioherbicidal activity of Trichoderma and Aspergillus species against parthenium has been well documented ( Javaid et al, 2013 , Javaid et al, 2014 ).…”

Mycoherbicide associated with the leaf spot of Chenopodium album L

“…There are numerous Phoma-like phytopathogenic fungi that are phytotoxin-producing. Todero et al (2018) reported that combining adjuvants with culture filtrate of Phoma sp. showed phytotoxic efficiency against Bidens pilosa L., Amaranthus retroflexus L. and Conyza canadensis L. Brun et al (2016) reported that metabolites produced by submerged fermentation of Phoma sp.…”

Bioherbicidal action of Phoma dimorpha fermented broth on seeds and plants of Senna obtusifolia 1

“…The gerbox boxes were conditioned in a BOD incubator chamber with temperature of 25 ºC and photoperiod of 12/12 h of light/darkness. The evaluations were carried out on the 3rd, 6th and 9th day after the application (Pedras & Ahiahonu 2004, Todero et al 2018b for the analysis of the appearance of symptoms, according to the scale presented in Table 1.…”

“…The Phoma fungi are a source of secondary metabolites with high biological activity, as some species secrete secondary metabolites, which may be used for the manufacturing of products with bio-biocidal activity, as well as others, aimed at the biological control of phytopathogenic fungi and insects (Wijeratne et al 2013). Several studies have shown that fungi of this genus produce a large variety of secondary metabolites with biological potential and they may be used for the formulation of bioproducts aimed at the agricultural environment (Hubbard et al 2014, Brun et al 2016, Todero et al 2018b.…”