Aims: Biocontrol products based on microorganisms and natural substances are promising alternatives to chemical pesticides that could contribute to develop a more sustainable agriculture. Here, we investigated the potential of cell-free culture filtrates (CFCFs) from two strains of the Bacillus subtilis group to inhibit Zymoseptoria tritici, a major fungal pathogen of wheat.
Methods And Results: Foliar application of CFCFs from Bacillus velezensis GA1 and Bacillus sp.
Pseudomonas spp. colonize diverse aquatic and terrestrial habitats and produce a wide variety of secondary metabolites, including lipopeptides. However, previous studies have often examined a limited number of lipopeptide-producing strains.
View Article and Find Full Text PDFA Correction to this paper has been published: https://doi.org/10.1038/s42003-020-01488-x.
View Article and Find Full Text PDFThe synthesis of 3,5-dicaffeoylquinic acid (3,5-DiCQA) has attracted the interest of many researchers for more than 30 years. Recently, enzymes belonging to the BAHD acyltransferase family were shown to mediate its synthesis, albeit with notably low efficiency. In this study, a new enzyme belonging to the GDSL lipase-like family was identified and proven to be able to transform chlorogenic acid (5-O-caffeoylquinic acid, 5-CQA, CGA) in 3,5-DiCQA with a conversion rate of more than 60%.
View Article and Find Full Text PDFLignin is the second most abundant polymer after cellulose in lignocellulosic biomass. Its aromatic composition and recalcitrant nature make its valorization a major challenge for obtaining low molecular weight aromatics compounds with high value-added from the enzymatic depolymerization of industrial lignins. The oxidation reaction of lignin polymer using laccases alone remains inefficient.
View Article and Find Full Text PDFPseudomonas strains isolated from oil contaminated soils were screened for biosurfactant production. Three out of eleven Pseudomonas isolates were selected for their high emulsifying activity (E24 value on n-hexadecane ~ 78%). These isolates (E39, E311 and E313) were identified as members of the P.
View Article and Find Full Text PDFSeveral Bacillus strains have been well studied for their ability to control soil-borne plant diseases. This property is linked to the production of several families of lipopeptides. Depending of their structure, these compounds show antifungal and/or plant systemic resistance inducing activities.
View Article and Find Full Text PDFSurfactin, a lipopeptide produced by Bacillus subtilis, is one of the most powerful biosurfactants known. This molecule consists of a cyclic heptapeptide linked to a β-hydroxy fatty acid chain. The isomery and the length of the fatty acid (FA) chain are responsible for the surfactin's activities.
View Article and Find Full Text PDFEnterococcus faecalis 14, a strain previously isolated from meconium, displayed activity against four Clostridium perfringens isolates when co-cultured on agar plates. The anti-Clostridium activity was ascribed to the production of enterocin DD14, which was subsequently purified. The minimum inhibitory concentration (MIC) of enterocin DD14 against one collection strain and one clinical C.
View Article and Find Full Text PDFBiosurfactants are important in many areas; however, costs impede large-scale production. This work aimed to develop a global sustainable strategy for the production of biosurfactants by a novel strain of Bacillus amyloliquefaciens. Initially, Bacillus sp.
View Article and Find Full Text PDFBioprocess Biosyst Eng
February 2017
Innovations in novel enzyme discoveries impact upon a wide range of industries for which biocatalysis and biotransformations represent a great challenge, i.e., food industry, polymers and chemical industry.
View Article and Find Full Text PDFBased on the exploration of data generated by genome sequencing, a bioinformatics approach has been chosen to identify the biosynthetic pathway of the siderophores produced by Aeromonas species. The amonabactins, considered as a virulence factor, represent a family of four variants of catechol peptidic siderophores containing Dhb, Lys, Gly, and an aromatic residue either Trp or Phe in a D-configuration. The synthesis operon is constituted of seven genes named amoCEBFAGH and is iron-regulated.
View Article and Find Full Text PDFMethicillin-resistant Staphylococcus aureus (MRSA) has become a worrisome superbug. This work aimed at studying the effects of two class IIb bacteriocins, enterocins DD28 and DD93 as anti-MRSA agents. Thus, these bacteriocins were purified, from the cultures supernatants of Enterococcus faecalis 28 and 93, using a simplified purification procedure consisting in a cation exchange chromatography and a reversed-phase high-performance liquid chromatography.
View Article and Find Full Text PDFBovine cruor, a slaughterhouse by-product, contains mainly hemoglobin, broadly described as a rich source of antimicrobial peptides. In the current context of food safety, bioactive peptides could be of interest as preservatives in the distribution of food products. The aim of this work was to study the α137-141 fragment of hemoglobin (Thr-Ser-Lys-Tyr-Arg), a small (653Da) and hydrophilic antimicrobial peptide.
View Article and Find Full Text PDFBurkholderia is an important genus encompassing a variety of species, including pathogenic strains as well as strains that promote plant growth. We have carried out a global strategy, which combined two complementary approaches. The first one is genome guided with deep analysis of genome sequences and the second one is assay guided with experiments to support the predictions obtained in silico.
View Article and Find Full Text PDFConsumers and governments have become aware how the daily diet may affect the human health. All proteins from both plant and animal origins are potential sources of a wide range of bioactive peptides and the large majority of those display health-promoting effects. In the meat production food chain, the slaughterhouse blood is an inevitable co-product and, today, the blood proteins remain underexploited despite their bioactive potentiality.
View Article and Find Full Text PDFThe use of microbial products has become a promising alternative approach to controlling plant diseases caused by phytopathogenic fungi. Bacteria isolated from the date palm tree rhizosphere of the Tunisian oasis ecosystem could provide new biocontrol microorganisms adapted to extreme conditions, such as drought, salinity and high temperature. The aim of this study was to screen bacteria isolated from the rhizosphere of the date palm tree for their ability to inhibit phytopathogenic fungi, and to identify molecules responsible for their antifungal activity.
View Article and Find Full Text PDFThe goal of this study was to investigate the effect of the environmental conditions such as the temperature change, incubation time and surface type on the resistance of Staphylococcus aureus biofilms to disinfectants. The antibiofilm assays were performed against biofilms grown at 20 °C, 30 °C and 37 °C, on the stainless steel and polycarbonate, during 24 and 48 h. The involvement of the biofilm matrix and the bacterial membrane fluidity in the resistance of sessile cells were investigated.
View Article and Find Full Text PDFThe self-assembly in aqueous solution of three lipopeptides obtained from Bacillus subtilis has been investigated. The lipopeptides surfactin, plipastatin and mycosubtilin contain distinct cyclic peptide headgroups as well as differences in alkyl chain length, branching and chain length distribution. Cryogenic transmission electron microscopy and X-ray scattering reveal that surfactin and plipastatin aggregate into 2 nm-radius spherical micelles, whereas in complete contrast mycosubtilin self-assembles into extended nanotapes based on bilayer ordering of the lipopeptides.
View Article and Find Full Text PDFUnlabelled: In recent years, food protein-derived bioactive peptides have received considerable attention because of their numerous health benefits. Amongst bioactive peptides, those with antihypertensive activity are receiving special attention due to their role in cardiovascular diseases. Goby protein hydrolysates (GPHs) prepared by treatment with five different crude bacterial proteases were found to exhibit varying degrees of angiotensin I-converting enzyme (ACE) inhibitory activity.
View Article and Find Full Text PDFAn endophytic whorl-forming Streptomyces sp. designated as TS3RO having antifungal activity against a large number of fungal pathogens, including Sclerotinia sclerotiorum, Rhizoctonia solani, Colletotrichum gloeosporioides, Cryphonectria parasitica, Fusarium oxysporum, Pyrenophora tritici-repentis, Epidermophyton floccosum, and Trichophyton rubrum, was isolated from surface-sterilized Catharanthus roseus stems. Preliminary identification showed that Streptomyces cinnamoneus subsp.
View Article and Find Full Text PDFSeveral Mallotus species (Euphorbiaceae) are used in Vietnam as edible plants or as traditional medicines for different indications, some related to the treatment of inflammatory diseases. This study investigated the antioxidant activities of 33 samples from 17 Vietnamese Mallotus species. We also evaluated potential cytotoxic activity against human cervix carcinoma HeLa and human lung fibroblast WI-38 cells.
View Article and Find Full Text PDFEthnopharmacological Relevance: The aim of the study was to evaluate the in vitro antitrypanosomal and antileishmanial activity of crude extracts of 10 plant species traditionally used in Benin to treat parasitic infections.
Materials And Methods: For each species, dichloromethane, methanol and aqueous extracts were tested. Their antitrypanosomal and antileishmanial activities were evaluated in vitro on Trypanosoma brucei brucei (strain 427) (Tbb) and on promastigotes of Leishmania mexicana mexicana (MHOM/BZ/84/BEL46) (Lmm).
This paper describes a number of articles that have been published on amino acid analysis using CE during the period from June 2003 to May 2005. This review article follows the previous ones of Smith (Electrophoresis 1999, 20, 3078-3083), Prata et al. (Electrophoresis 2001, 22, 4129-4138), and Poinsot et al.
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