Characterization of biosurfactants as insecticidal metabolites produced by Bacillus subtilis Y9

Abstract

Biosurfactants have been used for crop protection in integrated pest management programs, as they are generally biodegradable and environmentally friendly. While screening for insecticidal bacteria against green peach aphid, Myzus persicae, we found that a Bacillus isolate, Y9, exhibited strong surface tension activity and produced insecticidal metabolites. The insecticidal metabolites with surface tension activity were extracted from the cell‐free supernatant of Y9 and subjected to repetitive column chromatography and preparative high performance liquid chromatography (HPLC). Based on data from instrumental analyses, the metabolites were identified as surfactin isomers consisting of C14[Leu7], C14[Val7] and C15[Leu7]. The isomers with leucine showed higher insecticidal activity than the isomers with valine. Y9 was capable of producing biosurfactants as insecticidal metabolites against M. persicae, and showed potential for use as a biocontrol agent in an integrated pest management program.

Endophytic Bacillus spp. as a Prospective Biological Tool for Control of Viral Diseases and Non-vector Leptinotarsa decemlineata Say. in Solanum tuberosum L.

“…Bacterial endophytes have an advantage over bacteria inhabiting the rhizo- or phyllosphere, since living within a plant’s tissues represents an opportunity to be in constant “contact” with the plant’s cells, and endophytes become more integrated in plant metabolism than rhyzo- and phyllospheric microorganisms. PGPB strains show fungicidal ( Aydi Ben Abdallah et al, 2016 ), insecticidal ( Sorokan et al, 2016 ; Yang et al, 2017 ), and growth-promoting activities ( Sansinenea, 2019 ); synthesize antibiotics and biosurfactants ( Maksimov et al, 2020 ); and induce systemic resistance in plants against pathogens and pests ( Rashid and Chung, 2017 ). The entomopathogenic capacity of Bacillus thuringiensis strains to different orders of pests (Diptera, Lepidoptera, Hymenoptera, Coleoptera, Orthoptera, Hemiptera, etc.)…”

Endophytic Strain Bacillus subtilis 26DCryChS Producing Cry1Ia Toxin from Bacillus thuringiensis Promotes Multifaceted Potato Defense against Phytophthora infestans (Mont.) de Bary and Pest Leptinotarsa decemlineata Say

“…It has been shown that some surfactin-producing Bacillus strains can elicit ISR to Botrytis cinerea in grape, strawberry, and tomato plants [ 24 ] and Rhizoctonia solani in lettuce [ 25 ]. Recently, aphicidal and insecticidal activity of surfactin produced by B. subtilis and surfactin-producing strain B. subtilis 26D has been shown [ 13 , 14 , 26 ].…”

Identification of lipopeptide xantholysins from Pseudomonas sp. DJ15 and their insecticidal activity against Myzus persicae

“…Microorganisms with insecticidal activity were screened by mortality bioassays against M. persicae . Microbial cultures obtained as above were centrifuged at 12,000 x g for 20 min, and the resulting supernatant was used for bioassays as described earlier (Yang et al ). An isolate that exhibited the strongest insecticidal activity among the isolates was tested for the isolation of insecticidal metabolites.…”

“…Biosurfactants should have diverse effects on aphids because they consist of a wide range of molecules, such as glycolipids, lipopeptides, polysaccharide–protein complexes, and lipids (Lang & Wagner ). Recently, biosurfactants were introduced as alternative agents for aphid control (Kim et al ; Yang et al ). Because biosurfactants are generally safer environmentally than other chemicals are, they are a potentially sustainable tool in pest management programs (Crombie ).…”