Background: Cooling towers (CTs) are crucial to myriad industrial processes, supporting thermal exchange between fluids in heat exchangers using water from lakes and rivers as coolant. However, CT water can sometimes introduce microbial contaminants that adhere to and colonize various surfaces within the CT system. These microorganisms can form biofilms, significantly hindering the system's thermal exchange efficiency.
View Article and Find Full Text PDFIntroduction: The fungus significantly threatens maize crops in tropical soils. In light of this, biological control has emerged as a promising strategy to reduce fungicide costs and environmental risks. In this study, we aimed to test the antifungal activity of cell-free supernatant (CFS) from three (CT02, IM14, and LIS05) and one (LIS04) against , thereby contributing to the development of effective biocontrol measures.
View Article and Find Full Text PDFThe bacterial community from a cooling water system was investigated through culture-dependent and independent strategies, and the responses of planktonic and sessile bacteria (grown in glass slides and stainless-steel coupons) to antimicrobials of industrial and clinical use were assessed. The morphotypes with higher biofilm-forming potential were sp., sp.
View Article and Find Full Text PDFThe phytotelmata is a water-filled tank on a terrestrial plant, and it plays an important role in bromeliad growth and ecosystem functioning. Even though previous studies have contributed to elucidate the composition of the prokaryotic component of this aquatic ecosystem, its mycobiota (fungal community) is still poorly known. In the present work, ITS2 amplicon deep sequencing was used to examine the fungal communities inhabiting the phytotelmata of two bromeliads species that coexist in a sun-exposed rupestrian field of Southeastern Brazil, namely Aechmea nudicaulis (AN) and Vriesea minarum (VM).
View Article and Find Full Text PDFFusarium verticillioides is pathogenic to maize and mycotoxin-producer, causing yield losses, feed and food contamination, and risks to human and animal health. Endophytic (ISD04 and IPR45) and epiphytic (CT02 and IM14) bacteria from maize silks were tested in vitro and greenhouse against F. verticillioides and for hydrolytic enzyme production (cellulase, pectinase, protease, lipase, and chitinase).
View Article and Find Full Text PDFSuperbugs are a public health problem, increasing the need of new drugs and strategies to combat them. Our group has previously identified LyeTxI, an antimicrobial peptide isolated from spider venom. From LyeTxI, we synthesized and characterized a derived peptide named LyeTxI-b, which has shown significant and activity.
View Article and Find Full Text PDFBraz J Microbiol
September 2021
Yeasts can play important roles in promoting plant growth; however, little information is available in this regard for yeasts in water of bromeliad tanks. Here, we characterize the ability of 79 yeast isolates from tank bromeliad Vriesea minarum, an endangered species, to solubilize phosphate, secrete siderophores, and synthesize indole-3-acetic acid (IAA). The results showed that 67.
View Article and Find Full Text PDFBacterial extracellular polymeric substances (EPSs) present diverse properties of biotechnological interest, such as surface modification, metal adsorption and hydrophobic substances solubilization through surface tension reduction. Thus, there is a growing demand for new producing strains and structurally variable biomolecules with different properties. One approach for scanning this biodiversity consists of exploring environments under selective pressures.
View Article and Find Full Text PDFSci Rep
August 2019
Metataxonomic approach was used to describe the bacterial community from a creosote-contaminated aquifer and to access the potential for in situ bioremediation of the polycyclic aromatic hydrocarbons (PAHs) by biostimulation. In general, the wells with higher PAH contamination had lower richness and diversity than others, using the Shannon and Simpson indices. By the principal coordinate analysis (PCoA) it was possible to observe the clustering of the bacterial community of most wells in response of the presence of PAH contamination.
View Article and Find Full Text PDFBMC Microbiol
May 2019
Background: Although the most widely accepted mechanism of action for polymyxins is related to bacterial lysis via disruption, we hypothesized that this antimicrobial drug class could have other effects on Pseudomonas aeruginosa planktonic and sessile cells. Little is known regarding oxidative burst and zeta potential (ZP) data associated with the interaction between polymyxin B and P. aeruginosa cells.
View Article and Find Full Text PDFToxins (Basel)
April 2019
Bacterial keratitis is an ocular infection that can lead to severe visual disability. is a major pathogen of the eye. We recently demonstrated the strong antimicrobial activity of LyeTxI-b, a synthetic peptide derived from a toxin.
View Article and Find Full Text PDFThis study aimed to investigate for the first time the antibiofilm effectiveness of two chloramphenicol liposome formulations against biofilms of potentially pathogenic bacteria associated to corrosion isolated from the water of cooling towers from a Brazilian industry. Antibiofilm assays with liposomes were performed in 96-wells microtiter plates, and data was compared to free chloramphenicol treatment. Chloramphenicol-loaded liposomes were successfully produced using the dehydration-rehydration method, with vesicle diameters of 131 nm (100 nm membrane extrusion) and 182 nm (200 nm membrane extrusion) assessed by dynamic light scattering.
View Article and Find Full Text PDFBackground: New Delhi Metallo-b-lactamase (NDM-1) is an enzyme emerging around the world conferring resistance to a wide range of β-lactams agents and whose early detection is extremely important. We proposed to standardize the detection of the bla gene using the LOOP-mediated isothermal amplification technique (LAMP).
Methods: In all, 14 Gram-negative bacterial strains isolated from patients presenting pneumonia associated with mechanical ventilation were used for the bla standardization by LAMP.
Fungi have the ability to degrade vegetal cell wall carbohydrates, and their presence in the digestive tract of ruminants can minimize the effects of lignified forage on ruminal fermentation. Here, we evaluated enzyme production by Aspergillus spp. isolates from the digestive tracts of cattle grazed in tropical pastures during the dry season.
View Article and Find Full Text PDFis an important pathogen in opportunistic infections in humans. The increased incidence of antimicrobial-resistant isolates has highlighted the need for novel and more potent therapies against this microorganism. is known for presenting different compounds with diverse biological activities, such as anti-tumor and immunomodulatory activities.
View Article and Find Full Text PDFMem Inst Oswaldo Cruz
February 2015
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82 endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro assays.
View Article and Find Full Text PDFThe study was planned to quantify the distribution of bacteria between bulk water and biofilm formed on different materials in an industrial scale cooling tower system of an oil refinery operating with clarified and chlorinated freshwater (CCW) or chlorinated tertiary effluent (TRW) as makeup water. The sessile and planktonic heterotrophic bacteria and Pseudomonas aeruginosa densities were significantly higher in the cooling tower supplied with clarified and chlorinated freshwater (CTCW) (p < 0.05).
View Article and Find Full Text PDFBackground: The microbial bioemulsifiers was surface active compounds, are more effective in stabilizing oil-in-water emulsions. The yeasts have been isolated to produce bioemulsifiers from vegetable oils and industrial wastes.
Results: Trichosporon mycotoxinivorans CLA2 is bioemulsifier-producing yeast strain isolated from effluents of the dairy industry, with ability to emulsify different hydrophobic substrates.
The degradation of phenol (2-30 mM) by free cells and by alginate-immobilized cells of Aureobasidium pullulans FE13 isolated from stainless steel effluents was studied in batch cultures with saline solution not supplemented with nutrients or yeast extract. The rate at which the immobilized cells degrade phenol was similar to the rate at which the suspended cells could degrade phenol, for a concentration of up to 16 mM of phenol. The maximum phenol volumetric degradation rate for 16 mM phenol was found to be 18.
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