In-vitro antibacterial and antibiofilm activities and in-silico analysis of a potent cyclic peptide from a novel Streptomyces sp. strain RG-5 against antibiotic-resistant and biofilm-forming pathogenic bacteria.

The proliferation of multidrug-resistant and biofilm-forming pathogenic bacteria poses a serious threat to public health. The limited effectiveness of current antibiotics motivates the search for new antibacterial compounds. In this study, a novel strain, RG-5, was isolated from desert soil.

Antibacterial and antibiofilm properties of two cyclic dipeptides produced by a new desert Streptomyces sp. HG-17 strain against multidrug-resistant pathogenic bacteria.

Introduction: The emergence of multidrug-resistant bacteria and biofilms requires discovering new antimicrobial agents from unexplored environments.

Objectives: This study aims to isolate and characterize a new actinobacterial strain from the Hoggar Mountains in southern Algeria and evaluate its ability to produce bioactive molecules with potential antibacterial and antibiofilm activities.

Methods: A novel halotolerant actinobacterial strain, designated HG-17, was isolated from the Hoggar Mountains, and identified based on phenotypic characterizations, 16S rDNA sequence analysis, and phylogenetic analysis.

Effect of Cell-Free Supernatants on the Fungal Development, Transcriptome, and Aflatoxin B1 Production of .

Crop contamination by aflatoxin B1 (AFB1), an produced toxin, is frequently observed in tropical and subtropical regions. This phenomenon is emerging in Europe, most likely as a result of climate change. Alternative methods, such as biocontrol agents (BCAs), are currently being developed to reduce the use of chemicals in the prevention of mycotoxin contamination.

Rare Halophilic from Algerian Saharan Soils as Tools for Biotechnological Processes in Pharmaceutical Industry.

The Sahara Desert, one of the most extreme ecosystems in the planet, constitutes an unexplored source of microorganisms such as mycelial bacteria. In this study, we investigated the diversity of halophilic actinobacteria in soils collected from five regions of the Algerian Sahara. A total of 23 halophilic actinobacterial strains were isolated by using a humic-vitamin agar medium supplemented with 10% NaCl.

The Detection of Potential Native Probiotics spp. against Enteritidis, Infantis and Kentucky ST198 of Lebanese Chicken Origin.

continues to be a major threat to public health, especially with respect to strains from a poultry origin. In recent years, an increasing trend of antimicrobial resistance (AMR) in spp. was observed due to the misuse of antibiotics.

A New Saharan Strain of Streptomyces sp. GSB-11 Produces Maculosin and N-acetyltyramine Active Against Multidrug-Resistant Pathogenic Bacteria.

Multi-resistant bacterial pathogens are a major public health problem for treating nosocomial infections owing to their high resistance to antibiotics. The objective of this research was to characterize the bioactive molecules secreted by a novel moderately halophilic actinobacterium strain, designated GSB-11, exhibiting a strong antagonistic activity against several multidrug-resistant pathogenic bacteria. This potential strain was identified by phenotypic, genotypic (16S rRNA), and phylogenetic analyses.

New Antioxidant Active Packaging Films Based on Yeast Cell Wall and Naphtho-γ-Pyrone Extract.

The main objective of this work is the development of new active films based on yeast cell wall obtained by high-pressure homogenization (YCW-H) supplemented with naphtho-γ-pyrone (CL-NGP) extract, which is a bioactive compound produced by Aspergillus tubingensis G131 with great antioxidant potential. A complete characterization of the functional properties of the bioactive films, such as their structural, colour, thermal, mechanical, hydration and water vapour transport, was carried out to evaluate the influence of the addition of the antioxidant compounds. Likewise, the antioxidant capacity of the developed materials and the specific migration of NGPs in food simulants were evaluated.

Impact of the Inoculation Method of , Used as Biocontrol Agent, on T-2 Toxin Produced by and during the Malting Process.

In malt production, steeping and germination steps offer favorable environmental conditions for fungal proliferation when barley is already contaminated by species, T-2 toxin producers. However, the use of as a biocontrol agent can prevent this proliferation. Indeed, in previous work, a correlation between phenyllactic acid (PLA) production by and the reduction in and growth and T-2 toxin concentration was demonstrated.

A national study through a 'Farm-to-fork' Approach to determine Salmonella dissemination along with the Lebanese poultry production chain.

This cross-sectional study was conducted to determine the prevalence of Salmonella at different stages of the broiler production chain and layer flocks in addition to their antibiotic resistance profile and molecular patterns. Over a period of 3 years, different sample matrices were collected from Lebanese farms, slaughterhouses and retail markets. Out of 672 Salmonella serotyped, 514 were analysed for antimicrobial resistance and 214 for clonality using Pulsed-field gel electrophoresis (PFGE).

Whole-genome characterisation of TEM-1 and CMY-2 β-lactamase-producing Salmonella Kentucky ST198 in Lebanese broiler chain.

Objectives: Salmonella enterica subsp. enterica serovar Kentucky has been associated with the worldwide ciprofloxacin-resistant (CIP) Salmonella Kentucky sequence type 198 (ST198) epidemic clone, mostly recovered from poultry farms and products. The aim of this study was to examine whether this expanding clone exists in the Lebanese broiler chain.

Saccharothrix algeriensis NRRL B-24137, the first non-Streptomyces actinobacterium, produces holomycin after cystine feeding.

Saccharothrix algeriensis NRRL B-24137 is an actinobacterium isolated from Algerian Saharan soil. This strain has the ability to produce several dithiolopyrrolone antibiotic derivatives depending on the precursors added to the culture medium. This group of antibiotics is known for their potent antimicrobial and anticancer activities.

Biocontrol Agents and Natural Compounds Against Mycotoxinogenic Fungi.

Mycotoxins are toxic fungal secondary metabolites that contaminate food and feed. Mycotoxin contamination occurs as soon as environmental conditions are favorable for fungal growth and mycotoxin production, in the fields, during storage of raw materials and during industrial processes [..

Phenyllactic Acid Produced by Reduces and Growth and T-2 Toxin Concentration.

and are present in barley crops. Their toxic metabolites, mainly T-2 toxin, affect the quality and safety of raw material and final products such as beer. Therefore, it is crucial to reduce .

Mzabimycins A and B, novel intracellular angucycline antibiotics produced by sp. PAL114 in synthetic medium containing L-tryptophan.

In our previous studies, the production of four bioactive molecules by sp. PAL114 in complex ISP2 broth medium has been described. Three of these molecules belong to the angucycline family.

Impact of Spray-Drying on Biological Properties of Chitosan Matrices Supplemented with Antioxidant Fungal Extracts for Wine Applications.

Black aspergilli produce many bioactive compounds: enzymes, organic acids, and secondary metabolites. One such fungus, Aspergillus tubingensis G131, isolated from French Mediterranean vineyards, produces secondary metabolites with antioxidant properties that can be extracted with ethanol. In this study, crude antioxidant extracts obtained from A.

Antimicrobial activities of novel bipyridine compounds produced by a new strain of isolated from Saharan soil.

The actinobacterium strain ABH26 closely related to , isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium.

, A Promising Biocontrol Agent Against , the Main Aflatoxin B₁ Producer.

Crop contamination by aflatoxin B₁ is a current problem in tropical and subtropical regions. In the future, this contamination risk may be expanded to European countries due to climate change. The development of alternative strategies to prevent mycotoxin contamination that further contribute to the substitution of phytopharmaceutical products are thus needed.

Identification of multiple-derived peptides produced by Saccharomyces cerevisiae involved in malolactic fermentation inhibition.

An oenological strain of Saccharomyces cerevisiae was previously shown to produce a 5-10 kDa peptidic fraction responsible for the inhibition of malolactic fermentation (MLF). In the present study, we aim to further purify the anti-MLF peptides of this fraction. The yeast fermented synthetic grape juice medium was fractionated by ammonium sulfate precipitation combined with ultrafiltration.

Whole-genome sequencing of Aspergillus tubingensis G131 and overview of its secondary metabolism potential.

Background: Black Aspergilli represent one of the most important fungal resources of primary and secondary metabolites for biotechnological industry. Having several black Aspergilli sequenced genomes should allow targeting the production of certain metabolites with bioactive properties.

Results: In this study, we report the draft genome of a black Aspergilli, A.

Modeling-based optimization approaches for the development of Anti-Agrobacterium tumefaciens activity using Streptomyces sp TN71.

A new aerobic bacterium TN71 was isolated from Tunisian Saharan soil and has been selected for its antimicrobial activity against phytopathogenic bacteria. Based on cellular morphology, physiological characterization and phylogenetic analysis, this isolate has been assigned as Streptomyces sp. TN71 strain.

OTA Prevention and Detoxification by Actinobacterial Strains and Activated Carbon Fibers: Preliminary Results.

Ochratoxin A (OTA) is a mycotoxin produced by several species of and that contaminate food and feed raw materials. To reduce OTA contamination, we first tested in vitro, actinobacterial strains as potential biocontrol agents and afterward, through a physical decontamination method using activated carbon fibers (ACFs). Actinobacterial strains were screened for their ability to reduce OTA in solid co-culture with , which is the major OTA-producing species in European vineyards.

Ability of Soil Isolated Actinobacterial Strains to Prevent, Bind and Biodegrade Ochratoxin A.

Ochratoxin A (OTA) is one of the most important mycotoxins, and contaminates several agricultural products, particularly cereals, grapes, maize, barley, spices and coffee. The aim of this project was to reduce the levels of OTA by supplementing the artificially contaminated solutions with seven strains of actinobacteria (AT10, AT8, SN7, MS1, ML5, G10 and PT1) in order to evaluate their capacity for binding and metabolizing the OTA, as well as their ability to reduce the expression of the genes responsible for its production in . In the first part of this study, we evaluated the capacity of strains for binding OTA on their surfaces after 0, 30 and 60 min of incubation with PBS solution supplemented with OTA.

Antifungal and Antiochratoxigenic Activities of Essential Oils and Total Phenolic Extracts: A Comparative Study.

This study is intended to prevent ochratoxin A (OTA) production by S402 using essential oils (EOs) and total phenolic compounds extracted from plants and herbs. The EOs used in this study are the following: bay leaves, cumin, fenugreek, melissa, mint, and sage. As for the phenolic compounds, they were extracted from bay leaves, cumin, fenugreek, melissa, mint, sage, anise, chamomile, fennel, rosemary, and thyme.

Streptomyces sp. AT37 isolated from a Saharan soil produces a furanone derivative active against multidrug-resistant Staphylococcus aureus.

A novel actinobacterium strain, named AT37, showed a strong activity against some multidrug-resistant Staphylococcus aureus, including methicillin-resistant S. aureus MRSA ATCC 43300, other clinical isolates of MRSA and vancomycin resistant S. aureus VRSA S1.