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Enterococcus faecalis is a significant pathogen in healthcare settings and is frequently resistant to multiple antibiotics. This resistance is compounded by its ability to form biofilms, dense bacterial communities that are challenging to eliminate via standard antibiotic therapies. As such, targeting biofilm formation is considered a viable strategy for addressing these infections. This study assessed the effectiveness of surfactin, a cyclic lipopeptide biosurfactant synthesized by Bacillus subtilis natto NTU-18, in preventing biofilm formation by E. faecalis. Analytical characterization of surfactin was performed via liquid chromatography‒mass spectrometry (LC‒MS). Additionally, transcriptomic sequencing and quantitative PCR (qPCR) were used to investigate alterations in E. faecalis gene expression following treatment with surfactin. The data revealed notable suppression of crucial virulence-related genes responsible for pilus construction and exopolysaccharide synthesis, both of which are vital for E. faecalis adhesion and biofilm structure. Functional tests confirmed that surfactin treatment substantially reduced E. faecalis attachment to Caco-2 cell monolayers and curtailed exopolysaccharide production. Moreover, confocal laser scanning microscopy revealed significant thinning of the biofilms. These observations support the potential utility of surfactin as a therapeutic agent to manage biofilm-associated infections caused by E. faecalis. [ABSTRACT FROM AUTHOR]

[Display omitted] In laundry formulations, synergies between amphiphiles and other additives such as enzymes increase sustainability through a large decrease in energy consumption. However, traditional surfactants are derived from petroleum, requiring chemical modifications (sulfonation, ethoxylation, or esterification) and generating environmental pollution through toxicity and low degradability. Use of biosurfactants removes these issues. To provide a firmer basis for the use of biosurfactants, we report on the interactions between the industrial lipase LIPEX® and three common biosurfactants, rhamnolipids, sophorolipids, and surfactin. The model surfactant sodium dodecyl sulfate (SDS) is included in the study for comparison. A thorough characterization by Small-angle X-ray scattering (SAXS) provides valuable information on the enzyme's oligomerization and the surfactant micelles' ellipsoidal morphology. Additionally, the enzymatic activity and complex formation in different surfactant mixtures are studied using isothermal titration calorimetry, activity assays, and SAXS. SDS activates the enzyme while promoting a controlled association of monomers while the biosurfactants inhibit the enzyme, independent of their effects on its quaternary structure. Rhamnolipids and surfactin promote lipase dimerization while sophorolipids have no significant effect on lipase quaternary structure. Based on these data, we propose a partial replacement that allows the enzyme to retain enzymatic activity while improving the environmental footprint of the formulation. [ABSTRACT FROM AUTHOR]

This study investigated the antibacterial capacity and mechanism of surfactin (prepared by fermenting soybean meal with Bacillus subtilis SOPC5) against Staphylococcus aureus by examining its influences on the bacterial morphology, cell wall and membrane, as well as metabolic activity. The efficiency of surfactin in pork preservation was also investigated. HPLC-MS analysis showed that surfactin's purity reached 97.4%, containing five congeners. The minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) of surfactin against S. aureus were 1.6 and 3.2 mg/mL, respectively. The result of scanning electron microscopy observation revealed that 4 h of surfactin exposure resulted in deformation and even collapse of S. aureus. AKP assay, membrane potential analysis, extracellular protein and nucleic acid content measurement, and PI staining intensity assay showed that surfactin destroyed the cell wall and cell membrane of S. aureus. Decreases in iodonitrotetrazolium chloride levels and ATP enzyme activity indicated that surfactin could inhibit the metabolic ability of S. aureus. Furthermore, surfactin demonstrated an excellent antibacterial action on S. aureus within 5 days of pork storage without changing its texture. These findings suggest that sufactin has a great application potential in pork preservation. [ABSTRACT FROM AUTHOR]

Waste biomass deriving from agricultural activities has different destinations depending on the possibility of applying it to specific processes. As the waste biomass is abundant, cheap, and generally safe, it can be used for several applications, biogas production being the most relevant from the quantitative point of view. In this study, we have used a set of agricultural by-products (agro-waste) deriving from the post-harvest treatment of cereals and legumes as the growth substrate for selected biosurfactant-producing microbial strains. The agricultural by-products were easily metabolized and highly effective for the growth of microorganisms and the production of rhamnolipids and surfactin by Pseudomonas aeruginosa and Bacillus subtilis, respectively. In particular, the use of corn chaff ("bee-wings") was suitable for the production of rhamnolipids. Indeed, in corn-chaff-based media, rhamnolipids yields ranged from 2 to 18 g/L of fermentation broth. This study demonstrated that the use of waste raw materials could be applied to reduce the carbon footprint of the production of biosurfactants without compromising the possibility of having a suitable fermentation medium for industrial production. [ABSTRACT FROM AUTHOR]

Background: In biotechnology, B. subtilis is established for heterologous protein production. In addition, the species provides a variety of bioactive metabolites, including the non-ribosomally produced surfactin lipopeptide. However, to control the formation of the target product-forming enzyme, different expression systems could be introduced, including the principle of genetic code expansion by the incorporation of externally supplied non-canonical amino acids. Methods: Integration of an amber stop codon into the srfA operon and additional chromosomal integration of an aminoacyl-tRNA synthetase/tRNA mutant pair from Methanococcus jannaschii enabled site-directed incorporation of the non-canonical amino acid O-methyl-L-tyrosine (OMeY). In different fed-batch bioreactor approaches, OMeY-associated surfactin production was quantified by high-performance thin-layer chromatography (HPTLC). Physiological adaptations of the B. subtilis production strain were analyzed by mass spectrometric proteomics. Results: Using a surfactin-forming B. subtilis production strain, which enables high cell density fermentation processes, the principle of genetic code expansion was introduced. Accordingly, the biosynthesis of the surfactin-forming non-ribosomal peptide synthetase (NRPS) was linked to the addition of the non-canonical amino acid OMeY. In OMeY-associated fed-batch bioreactor fermentation processes, a maximum surfactin titre of 10.8 g/L was achieved. In addition, the effect of surfactin induction was investigated by mass spectrometric proteome analyses. Among other things, adaptations in the B. subtilis motility towards a more sessile state and increased abundances of surfactin precursor-producing enzymes were detected. Conclusions: The principle of genetic code expansion enabled a precise control of the surfactin bioproduction as a representative of bioactive secondary metabolites in B. subtilis. This allowed the establishment of inducer-associated regulation at the post-transcriptional level with simultaneous use of the native promoter system. In this way, inductor-dependent control of the production of the target metabolite-forming enzyme could be achieved. [ABSTRACT FROM AUTHOR]

A new lipopeptide-producing strain Cytobacillus sp. R3-1 was isolated from the production water of the Daqing oilfield in China and identified based on 16S rRNA gene sequence analyses. The strain R3-1 is capable of simultaneously producing both of the surfactin and fengycin, the two major families of the lipopeptide biosurfactant. The chemical structures of the surfactin and fengycin were confirmed by a combination of the ESI-MS, FT-IR, and amino acid analyses, and the impact of various temperatures, pH, and NaCl concentrations on the emulsifying activity (E24) was investigated. The lipopeptide biosurfactant produced by the strain R3-1 exhibited strong emulsifying activity with E24 value over 60% on crude oil and different hydrocarbons, including the cyclohexane, hexadecane, benzene, toluene, kerosene, diesel oil, and liquid paraffin. Meanwhile, it showed excellent emulsifying activity across a broad range of conditions of the temperature up to 60 °C, NaCl tolerance up to 100 g/L, and pH values between 5 and 9, which suggests that the strain R3-1 is a valuable microbial candidate for the simultaneous production of the surfactin and fengycin lipopeptide biosurfactant with strong emulsifying properties and stability under diverse environmental conditions and is a potential application in environmental bioremediation and enhanced oil recovery. [ABSTRACT FROM AUTHOR]

Potatoes are one of the most important food crops worldwide, but their growth and development are often seriously threatened by potato bacterial wilt. The wettable powder produced by Bacillus amyloliquefaciens C4 under optimized fermentation conditions effectively inhibits potato bacterial wilt. In this study, lipopeptide antibiotics were identified via PCR and MALDI-TOF-MS, and their antibacterial activity was determined. The optimal formulation of C4 wettable powder was optimized via a single-factor experiment combined with a response surface. The effect of C4 wettable powder on potato bacterial wilt was evaluated. In the antibacterial activity test, surfactin showed better inhibition ability. After determining the optimal liquid fermentation conditions and wettable powder formula, the surfactin activity increased to 540.15 mg/L, and the C4 wettable powder activity reached 69.67 × 108 cfu/g. The results of the pot experiment showed that the best cost-effectiveness was achieved under 500 times dilution and spraying, with a control effect of 79.05 ± 24.79%. The physiological and biochemical results showed that C4 wettable powder could induce rapid defense enzyme responses in leaves and enhance plant resistance to pathogenic bacteria. The results showed that C4 wettable powder effectively controlled potato bacterial wilt, and its application method was determined. [ABSTRACT FROM AUTHOR]

The increasing trend of antibiotic resistance among pathogenic bacteria is a worldwide problem. Streptomyces produce a number of bioactive compounds such as antibacterial. This study aimed to investigate the effect of different media and incubation time in increasing the antibacterial activity of marine sponge-associated Streptomyces spp. and characterize antibacterial compounds of marine sponge-associated Streptomyces spp. against pathogenic bacteria. Among the three tested media and some days of incubation times, Streptomyces spp. produce more antibacterial activity when grown using modified molasses medium at 15 days incubation. The ethyl acetate extracts of Dbi28t exhibited a significant inhibitory zone against Extended Spectrum β-Lactamase (ESBL)-producing Escherichia coli, Providencia rettgeri then followed by Proteus mirabilis and Pseudomonas putida and the results were higher than some commercial antibiotics. This study has identified nine antibacterial compounds in Dbi28t using Liquid Chromatography-tandem Mass Spectrometric (LC-MS/MS) analysis, with the most abundance belonging to pumilacidin A, then followed by pumilacidin B, surfactin B, surfactin A, phenazostatin B, chalcomycin B, neopyrrolomycin C, saquayamycin A and saphenamycin. This work provides the first report from a Streptomyces sp. Dbi28t produced pumilacidin, surfactin and other bioactive compounds with the modified molasses medium for optimization of characterization of its antibacterial compounds. [ABSTRACT FROM AUTHOR]

Biofilms are highly important to be controlled in food industries for two major reasons: (i) pathogenic microorganisms can impact public health causing foodborne illness outbreaks, and (ii) food-spoilage microorganisms can cause economic impacts due to the loss of organoleptic quality. Listeria monocytogenes and Pseudomonas fluorescens are ubiquitous and highly representative of both problems. The presence of these bacteria in biofilms must be controlled, and new strategies need to be implemented. Among those strategies, the use of biosurfactants is promising. The present work studied the application of a surfactin produced by Bacillus velezensis H2O-1 to inhibit corrosion, planktonic growth, microbial adhesion, and biofilm formation by two strains of L. monocytogenes and one strain of P. fluorescens. For that purpose, scanning electron microscopy, epifluorescence microscopy, and the determination of the physicochemical characteristics of different surfaces, microorganisms and biofilms were performed. Biofilm reduction on conditioned surfaces reached up to 75%. When the surfactin was added to the media, the planktonic inhibition values reached 87%, and biofilms were inhibited by up to 100%. The analyzed images suggest that this molecule has great potential to postpone steel corrosion. The results demonstrated the great potential of this biomolecule in the food industry against both microorganisms, thus enhancing food safety and shelf-life. [ABSTRACT FROM AUTHOR]

Abstract Spodoptera litura (S. litura) is a polyphagous pest of the family Lepidoptera, which causes damage and yields losses to many crops. The long-term use of chemical pesticides for control not only seriously threatens environmental health, but also causes S. litura to develop drug resistance. Therefore, there is an urgent need to develop environmentally safe and friendly biogenic pesticides. However, the mechanism of action of the secondary metabolite (surfactin) of Bacillus Vélezensis (B. vélezensis) on lepidopteran pests (S. litura) has not been reported yet. We found that several metabolites and genes in S. litura were affected by surfactin exposure. The expressions of the metabolites (protoporphyrinogen (PPO), gluconolactone (GDL), and L-cysteate) were significantly down-regulated while glutamate and hydroxychloroquine were significantly up-regulated. The expression levels of genes related to drug metabolism and detoxification, include the glutathione s-transferase (GST) gene family and acetaldehyde dehydrogenase (ALDH), and apoptosis-inhibiting genes (seven in absentia homolog 1(SIAH1)) were significantly decreased. In addition, pathological changes occurred in intestinal wall cells, Malpighian tubule cells, and nerve cells of S. litura under surfactin stress. Conclusively, our results suggest that surfactin induces an increase in reactive oxygen species (ROS) and damages S. litura cells. Furthermore, based on the integrated analysis of transcriptomic and metabolomic data, it is hypothesized that surfactin may also trigger neurotoxicity and cardiotoxicity in S. litura while hindering the insect’s detoxification processes. This study lays a foundation for further exploration of surfactin as a potential biopesticide.

Surfactin lipopeptides (LPs) are a compelling class of biosurfactants with notable antimicrobial and anticancer properties. This study presents a novel approach by integrating bioinformatics tools to assess the drug potential of Surfactin, specifically focusing on its antibacterial, antifungal activities, and cancer cell-line toxicity. Silver nanoparticles (AgNPs) were synthesized using Surfactin, a biosurfactant derived from Bacillus subtilis KLP2016, as a capping agent, both in the presence and absence of Surfactin, to evaluate its impact on nanoparticle stability and bioactivity. The Surfactin-capped AgNPs demonstrated enhanced stability, uniformity, and antimicrobial efficacy, confirmed through UV–VIS spectroscopy, FE-SEM, and X-ray diffraction analysis. The bioinformatics approach, including ADMET and PASS analysis, revealed the potential of Surfactin as a potent antimicrobial and anticancer agent. In addition, molecular docking studies further validated the interaction of Surfactin with key microbial cell-wall enzymes and proteins, underscoring its therapeutic potential. These findings suggest that Surfactin-stabilized AgNPs, combined with bioinformatic predictions, could pave the way for innovative antimicrobial and anticancer therapies. [ABSTRACT FROM AUTHOR]

Flax (Linum usitatissimum) is a versatile plant used in a range of applications, from textiles to nutrition. Surfactin, a cyclic lipopeptide biosurfactant produced by bacteria such as Bacillus subtilis, has potential as a biocontrol agent or as a plant defense inducer in agriculture. This work aims to determine the effects of surfactin treatment at two kinetic points on the metabolism of flax hydroponic cultures, using advanced metabolomic techniques, including 1H NMR and LC-MS analyses. Surfactin, detected in the roots, has a significant local impact on the metabolic profiles of flax roots, leading mainly to a higher content of cyanogenic compounds and amino acids and a lower content of carbohydrates. Surfactin, which is not detected in the aerial parts, also induces contrasted changes in amino acids, sugars, and secondary metabolite accumulation between stems and leaves. Surfactin treatment of flax leads to both a local and systemic effect on flax metabolism. These changes suggest that plant response to surfactin treatment could induce an enhanced plant defense. This could suggest potential applications of surfactin in the agricultural field as a biostimulant or biocontrol agent, to limit the use of chemical compounds in culture, and to limit their negative impact on both health and the environment. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION The extensive use of additives in ultra‐processed foods presents considerable health concerns. In light of the growing consumer demand for clean labels, a prominent trend is the development of multifunctional food additives that are both natural and beneficial to health. Surfactin, a compound produced by Bacillus subtilis, features both hydrophilic and hydrophobic groups and is noted for its safety, emulsifying and antimicrobial properties. This compound holds significant potential as a multifunctional additive in flour‐based products. The present study aimed to evaluate the effects of surfactin on the physicochemical properties of dough and the quality of steamed bread, as well as to investigate the underlying mechanisms.The results showed that the addition of surfactin significantly improved its rheological properties, increased elasticity and viscosity, improved extension resistance and increased disulfide bonding content in dough (P < 0.05), subsequently stabilizing the gluten network structure. With a 0.3% surfactin addition, the digestibility of steamed bread significantly reduced. After storing for 7 days, surfactin inhibited water migration, reduced the transfer from bound water to free water, delayed starch recrystallization, improved resistance to starch retrogradation and markedly extended the shelf life in steamed bread.The addition of surfactin improved the quality of steamed bread through stabilizing the gluten network structure and improving storage properties, presenting it as a promising natural, multifunctional food additive for flour product innovation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Discovering more novel antimicrobial compounds has become a keen research problem. In this study, YA215 genome was sequenced by the Illumina HiSeq + PacBio sequencing platform. Genome assembly was performed by Unicycler software and the gene clusters responsible for secondary metabolite biosynthesis were predicted by antiSMASH. The genome comprised 3976514 bp and had a 46.56% G + C content. 3809 coding DNA sequences, 27 rRNAs, 86 tRNAs genes, and 79 sRNA were predicted. Strain YA215 was re-identified as Bacillus velezensis based on ANI and OrthoANI analysis. In the COG database, 23 functional groups from 3090 annotations were predicted. In the GO database, 2654 annotations were predicted. 2486 KEGG annotations linked 41 metabolic pathways. Glycosyl transferases, polysaccharide lyases, auxiliary activities, glycoside hydrolases, carbohydrate esterases, and carbohydrate-binding modules were predicted among the 127 annotations in the CAZy database. AntiSMASH analysis predicted that B. velezensis YA215 boasted 13 gene clusters involved in synthesis of antimicrobial secondary metabolites including surfactin, fengycin, macrolactin H, bacillaene, difficidin, bacillibactin, bacilysin, and plantazolicin. Three of the gene clusters (gene cluster 5, gene cluster 9, and gene cluster 10) have the potential to synthesize unknown compounds. The research underscore the considerable potential of secondary metabolites, identified in the genomic composition of B. velezensis YA215, as versatile antibacterial agents with a broad spectrum of activity against pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Significant agricultural losses are caused by the phytopathogenic fungi Botrytis cinerea and Phytophthora infestans, as well as bacteria of the Ralstonia solanacearum species. The present work aimed to isolate rhizobacteria for simultaneous biocontrol of these three phytopathogenic species and to suggest the mechanisms of their antagonistic action. Among 120 Bacillus spp. isolated from soils, Bacillus velezensis and Bacillus licheniformis strains displayed the highest activity against all three phytopathogens. A rapid, polymerase chain reaction-based method for detecting nonribosomal peptide synthetase genes was developed to elucidate the genetic basis of these traits. The presence of fenA, srfAA, ppsA, and lchAA genes, encoding fengycin/surfactin/plipastatin synthetases and lichenysin synthase, was revealed in the strains' genomes. The whole genome sequencing (WGS) of B. velezensis R22 showed that it contains 4,081,504 bp (with G + C content 46.35%), 4087 genes for 3935 proteins, 72 tRNAs, 14 rRNAs, and 5 ncRNAs. WGS allowed the prediction of 10 complete clusters for secondary metabolites with putative antimicrobial activity: difficidin, fengycin, bacillaene, butyrosin, bacillibactin, bacilysin, surfactin, macrolactin H, macrolactin R22, and velezensin. LC-MS and high-sensitivity UHPLC-Q-TOF LC-MS/MS analysis were used to search for the predicted metabolites in cell-free supernatants of B. velezensis R22. The compounds with the strongest antifungal activity are surfactin with a C15 β-OH fatty acid chain; two homologous forms of fengycin A; and two fengycin B homologues containing C16 and C17 β-hydroxy fatty acid chains. The broad antimicrobial spectrum of B. velezensis R22 and its molecular characterization provide a good basis for the future development of plant protection preparations. [ABSTRACT FROM AUTHOR]

Anthracnose, caused by Colletotrichum spp., is a threat to strawberry production globally. Unlike their chemical counterparts, microbial biofungicides offer a method of postharvest fungal disease control that is safe, sustainable and less affected by pathogen resistance. The present study evaluated the antifungal effects of three bacteria, Bacillus velezensis strains SH1 and SH2 and Pseudomonas azotoformans strain SH3, obtained from sheep manure compost tea. The bacteria or their cell‐free filtrates were tested against Colletotrichum acutatum and Colletotrichum gloeosporioides in bioassays and against strawberry anthracnose. In addition, precipitated or extracted extracellular fractions were tested to determine the effects on membrane permeability of Colletotrichum spp. spores. Confrontation assay results showed all bacteria inhibited mycelial growth, with B. velezensis SH1 and P. azotoformans SH3 being the most effective. All cell‐free filtrates inhibited mycelial growth with B. velezensis SH1 and SH2 resulting in the highest inhibition. The bacteria suppressed anthracnose lesions on strawberry fruit although effective treatments varied by causal mould. B. velezensis SH1 and SH2 significantly permeabilized spore membranes, indicating antibiosis as a possible mode of action. Investigation into antimicrobial compound production found various homologues of the lipopeptides fengycin, iturin and surfactin were produced by B. velezensis SH1 and SH2. Results suggest that lipopeptides produced by B. velezensis strains permeabilize Colletotrichum cell membranes, and that fengycins were the most inhibitory of the lipopeptides against Colletotrichum spp. [ABSTRACT FROM AUTHOR]

Bacillus lipopeptides have been reported to display anti-obesity effects. In the present study, Lipopeptides from Bacillus velezensis FJAT-45028 that consisted of iturin, fengycin and surfactin were reported. The lipopeptides exhibited a strong lipase inhibition activity in a concentration-dependent manner with a half maximal inhibitory concentration of 0.012 mg/mL, and the inhibition mechanism and type were reversible and competitive, respectively. Results of CCK8 assay showed that 3T3-L1 preadipocyte cells were completely viable under treatment of 0.050–0.2 mg/mL lipopeptides for 24 or 48 h. It was found that the lipopeptides could increase lipid droplets in the differentiated 3T3-L1 adipocytes in tested concentration and suppress the expression of peroxisome proliferator-activated receptor gamma (PPARγ). These results indicated the potential anti-obesity mechanism of the tested lipopeptides might be to inhibit lipase activity but not to suppress lipid accumulation in the adipocytes. Moreover, the lipopeptides could elevate glucose utilisation by 14.43%–33.81% in the differentiated 3T3-L1 adipocytes. [ABSTRACT FROM AUTHOR]

Spodoptera litura (S. litura) is a polyphagous pest of the family Lepidoptera, which causes damage and yields losses to many crops. The long-term use of chemical pesticides for control not only seriously threatens environmental health, but also causes S. litura to develop drug resistance. Therefore, there is an urgent need to develop environmentally safe and friendly biogenic pesticides. However, the mechanism of action of the secondary metabolite (surfactin) of Bacillus Vélezensis (B. vélezensis) on lepidopteran pests (S. litura) has not been reported yet. We found that several metabolites and genes in S. litura were affected by surfactin exposure. The expressions of the metabolites (protoporphyrinogen (PPO), gluconolactone (GDL), and L-cysteate) were significantly down-regulated while glutamate and hydroxychloroquine were significantly up-regulated. The expression levels of genes related to drug metabolism and detoxification, include the glutathione s-transferase (GST) gene family and acetaldehyde dehydrogenase (ALDH), and apoptosis-inhibiting genes (seven in absentia homolog 1(SIAH1)) were significantly decreased. In addition, pathological changes occurred in intestinal wall cells, Malpighian tubule cells, and nerve cells of S. litura under surfactin stress. Conclusively, our results suggest that surfactin induces an increase in reactive oxygen species (ROS) and damages S. litura cells. Furthermore, based on the integrated analysis of transcriptomic and metabolomic data, it is hypothesized that surfactin may also trigger neurotoxicity and cardiotoxicity in S. litura while hindering the insect's detoxification processes. This study lays a foundation for further exploration of surfactin as a potential biopesticide. [ABSTRACT FROM AUTHOR]

(1) T-2 toxin synthesized by Fusarium oxysporum (F. oxysporum) can cause deterioration of dried fish and endanger human health. (2) The molecular mechanism by which antibacterial lipopeptides surfactin inhibited F. oxysporum growth and toxin production was elucidated by investigating the intracellular ROS production pathway and the subcellular distribution and transcriptional activity of the transcription factor Yap1 and its regulation of Tri5 gene in F. oxysporum. (3) Surfactin caused hyphal damage and nucleic acid and protein leakage; thus, the growth of F. oxysporum was disrupted. Surfactin's excessive accumulation of intracellular ROS triggered the translocation of transcription factor Yap1 into the nucleus, resulting in toxin cluster gene Tri5 expression inhibition, thereby blocking T-2 toxin synthesis. (4) This is a novel mechanism by which surfactin inhibits the growth and T-2 toxin synthesis of F. oxysporum from multiple aspects, including cell structural integrity and the ROS-Yap1 signaling pathway. (5) This study provides a theoretical basis for the application of surfactin in the antifungal control of aquatic dry products. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi (e.g., Rhizophagus species) recruit specific bacterial species in their hyphosphere. However, the chemical interplay and the mutual benefit of this intricate partnership have not been investigated yet, especially as it involves bacteria known as strong producers of antifungal compounds such as Bacillus velezensis. Here, we show that the soil-dwelling B. velezensis migrates along the hyphal network of the AM fungus R. irregularis , forming biofilms and inducing cytoplasmic flow in the AM fungus that contributes to host plant root colonization by the bacterium. During hyphosphere colonization, R. irregularis modulates the biosynthesis of specialized metabolites in B. velezensis to ensure stable coexistence and as a mechanism to ward off mycoparasitic fungi and bacteria. These mutual benefits are extended into a tripartite context via the provision of enhanced protection to the host plant through the induction of systemic resistance. [Display omitted] • B. velezensis colonizes the entire mycelial network more efficiently than roots • Bacillus uses fungal hyphae as highways for soil invasion and to colonize new plant • The lipopeptide surfactin plays key roles in the chemical ecology of the interaction • The microbial partnership enhances the systemic resistance of tomato against Botrytis Anckaert et al. investigate the dynamics of Rhizophagus hyphae colonization by B. velezensis. Reduced production of bacterial toxic metabolites triggered by the fungus leads to an unsuspected stable coexistence. This interaction brings benefits to both microbes and provides positive effects to the host plant, which is more resistant to disease. [ABSTRACT FROM AUTHOR]

【Objective】The study aimed to construct a transposable mutant library of highly efficient insecticidal Bacillus subtilis YZ-1 and screen for mutant strains with high yields of surfactant, thereby providing preliminary materials for the analysis and development of the regulation mechanism of surfactant synthesis in YZ-1. 【Method】 The strain YZ-1 was transformed using the shuttle vector pMarA carrying the transposon TnYLB-1 and a temperature-sensitive replicative protein. The transposon was induced to transpose at a high temperature of 50 ℃, and the transposon mutants were subjected to resistance culture rescreening to construct a transposon mutant library for the YZ-1 strain. A combination of initial screening with the blood agar plate method, rescreening with bromothymol blue colorimetry, and quantitative detection with HPLC was used to select mutants with significantly enhanced surfactin synthesis from the mutant library. 【Result】 Through natural transformation, the pMarA plasmid was successfully introduced into B.subtilis YZ-1, resulting in a YZ-1 mutant library containing 3000 transposon mutants. From this library, 11 candidate strains with enhanced surfactin synthesis were screened. HPLC detection revealed that compared to the YZ-1 wild type, there were 5 mutants (M1, M6, M7, M8 and M9) with increased or similar levels of surfactin synthesis, and 6 mutants (M2, M3, M4, M5, M10 and M11) with significantly decreased synthesis. Among them, the M8 mutant, which had the highest surfactin yield at 282.4 mg/L, showed a 13.7% increase compared to the wild type, while the M2 strain, with the lowest yield at 47.53 mg/L, experienced an 80.9% decrease compared to the wild type. 【Conclusion】 The addition of a resistance rescreening cultivation step can improve the accuracy of the YZ-1 mutant library. High-throughput screening based on blood agar culture and bromothymol blue assay can preliminarily select mutant strains with significant changes in lipopeptide products. [ABSTRACT FROM AUTHOR]

[Objectives] The paper aimed to evaluate the lactogenic immunity of sows by orally surfactin (fermentation product of Bacillus subtilis OKB105), so as to improve the intestinal immunity of piglets and reduce the incidence rate of Porcine epidemic diarrhea in piglets. [Methods] 0.05% surfactin (1 g·d-1) was added to the diet of pregnant sows, and colostrum on the first day after delivery was collected. First, the composition of milk was analyzed, and then the number and proliferation capacity of immune cells in colostrum were determined by flow cytometry. Subsequently, ELISA experiments were conducted to determine the content of cytokines and antiviral proteins in milk. Finally, the plaque assay was used to verify the ability of milk supernatant to inhibit Porcine epidemic diarrhea virus. [Results] Oral administration of surfactin significantly increased the content of milk protein in colostrum in sows (P<0.05), significantly increased the number of CD14+ monocytes and CD3+T lymphocytes in colostrum (P<0.01), significantly enhanced the proliferation ability of lymphocytes in colostrum (P<0.01), significantly increased the content of IFN-γ and CCL28 (P<0.01), and significantly increased the contents of sIgA, IgG, TGF-β, IL-6 and lactoferrin (P<0.05) . The titer of sow oral surfactin colostrum supernatant against PEDV was 1:16, while the blank sow was 1:4. [Conclusions] Oral administration of surfactin could improve the cellular and humoral immune levels in sow colostrum, providing sufficient lactogenic immunity protection against diarrhea caused by neonatal piglet PED. [ABSTRACT FROM AUTHOR]

Microbial lipopeptides are synthesized by nonribosomal peptide synthetases and are composed of a hydrophobic fatty acid chain and a hydrophilic peptide moiety. These structurally diverse amphiphilic molecules can interact with biological membranes and possess various biological activities, including antiviral properties. This study aimed to evaluate the cytotoxicity and antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of 15 diverse lipopeptides to understand their structure-activity relationships. Non-ionic lipopeptides were generally more cytotoxic than charged ones, with cationic lipopeptides being less cytotoxic than anionic and non-ionic variants. At 100 µg/mL, six lipopeptides reduced SARS-CoV-2 RNA to undetectable levels in infected Vero E6 cells, while six others achieved a 2.5- to 4.1-log reduction, and three had no significant effect. Surfactin, white line-inducing principle (WLIP), fengycin, and caspofungin emerged as the most promising anti-SARSCoV-2 agents. Detailed analysis revealed that these four lipopeptides affected various stages of the viral life cycle involving the viral envelope. Surfactin and WLIP significantly reduced viral RNA levels in replication assays, comparable to neutralizing serum. Surfactin uniquely inhibited viral budding, while fengycin impacted viral binding after pre-infection treatment of the cells. Caspofungin demonstrated a lower antiviral effect compared to the others. Key structural traits of lipopeptides influencing their cytotoxic and antiviral activities were identified. Lipopeptides with a high number of amino acids, especially charged (preferentially anionic) amino acids, showed potent anti-SARS-CoV-2 activity. This research paves the way for designing new lipopeptides with low cytotoxicity and high antiviral efficacy, potentially leading to effective treatments. IMPORTANCE This study advances our understanding of how lipopeptides, which are molecules mostly produced by bacteria, with both fat and protein components, can be used to fight viruses like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). By analyzing 15 different lipopeptides, researchers identified key structural features that make some of these molecules particularly effective at reducing viral levels while being less harmful to cells. Specifically, lipopeptides with certain charged amino acids were found to have the strongest antiviral effects. This research lays the groundwork for developing new antiviral treatments that are both potent against viruses and safe for human cells, offering hope for better therapeutic options in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: Surfactin, usually produced by microbial metabolism, has many advantages including low toxicity, high biodegradability, and stability at extreme pH levels and temperatures, making it suitable for industry. However, its commercial production has not yet been achieved. RESULTS: A strain with a strong surfactin‐producing ability was isolated and identified as Bacillus subtilis SOPC5, based on the appearance of colonies, microscopic observation, and 16S rDNA sequencing. The isolate exhibited significant tolerance to acid, bile, gastric, and intestinal juices, and was sufficiently susceptible to antibiotics. Bacillus subtilis SOPC5 showed high levels of auto‐aggregation and surface hydrophobicity, and a strong capacity to secrete protease, amylase, and cellulase. The strain also exhibited antibacterial activity against Staphylococcus aureus 10 306 with a antibacterial circle diameter of 18.0 ± 1.1 mm. The maximal yield of surfactin (1.32 mg mL−1) was obtained by fermenting soybean meal (SBM) using the isolate under the following conditions: SBM 86 g L−1, inoculation 1.5 × 107 CFU mL−1, FeSO4 1.2 mg L−1, MnSO4 2.6 mg L−1, MgSO4 0.5 mg mL−1, L‐Glu 4 mg L−1, temperature 33 °C, duration 120 h, and shaking at 210 rpm. The purity of surfactin was 97.42% as measured by high‐performance liquid chromatography (HPLC). The half inhibitory concentration (IC50) values for surfactin to scavenge 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cation (ABTS·+) were 1.275 ± 0.11 and 0.73 ± 0.08 mg mL−1, respectively. CONCLUSION: This study provides a scientific basis for the application of B. subtilis SOPC5 (as a potential probiotic) and the preparation of its metabolic product (surfactin). © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Bacillus spp. produce numerous antimicrobial metabolites. Among these metabolites, cyclic lipopeptides (CLP) including fengycins, iturins, and surfactins are known to have varying antifungal activity against phytopathogenic fungi. The differential activities of CLP have been attributed to diverse mechanisms of action on fungal membranes. However, the precise biochemical determinants driving their antifungal modes of action have not been conclusively identified. In this study, three plant pathogenic fungi of varying lipopeptide sensitivities, Alternaria solani , Cladosporium cucumerinum , and Fusarium sambucinum , were studied to determine how their cell membrane lipid compositions may confer sensitivity and/or tolerance to fengycin, iturin, and surfactin. Results indicated that sensitivity to all three lipopeptides correlated with lower ergosterol content and elevated phospholipid fatty acid unsaturation. Fungal sensitivity to surfactin was also notably different than fengycin and iturin, as surfactin was influenced more by lower phosphatidylethanolamine amounts, higher levels of phosphatidylinositol, and less by phospholipid fatty acyl chain length. Results from this study provide insight into the fungal membrane composition of A. solani , F. sambucinum , and C. cucumerinum and the specific membrane characteristics influencing the antifungal effectiveness of fengycin, iturin, and surfactin. Understanding of these determinants should enable more accurate prediction of sensitivity-tolerance outcomes for other fungal species exposed to these important CLP. • Fungi were differentially sensitive to Bacillus lipopeptides. • Lipopeptide sensitivity correlated with ergosterol content. • Phospholipid fatty acid unsaturation and chain length were sensitivity determinants. • Surfactin sensitivity was different and influenced by phospholipid polar headgroups. [ABSTRACT FROM AUTHOR]

Surfactin, a potent biosurfactant produced by Bacillus subtilis, is synthesized using a non-ribosomal peptide synthetase (NRPS) encoded by the srfAA-AD operon. Despite its association with quorum sensing via the ComX pheromone, the dynamic behavior and in vivo quantification of the NRPS complex remain underexplored. This study established an in vivo quantification system using fluorescence labeling to monitor the availability of surfactin-forming NRPS subunits (SrfAA, SrfAB, SrfAC, and SrfAD) during bioprocesses. Four Bacillus subtilis sensor strains were constructed by fusing these subunits with the megfp gene, resulting in strains BMV25, BMV26, BMV27, and BMV28. These strains displayed growth and surfactin productivity similar to those of the parental strain, BMV9. Fluorescence signals indicated varying NRPS availability, with BMV27 showing the highest and BMV25 showing the lowest relative fluorescence units (RFUs). RFUs were converted to the relative number of NRPS molecules using open-source FPCountR package. During bioprocesses, NRPS availability peaked at the end of the exponential growth phase and declined in the stationary phase, suggesting reduced NRPS productivity under nutrient-limited conditions and potential post-translational regulation. This study provides a quantitative framework for monitoring NRPS dynamics in vivo, offering insights into optimizing surfactin production. The established sensor strains and quantification system enable the real-time monitoring of NRPS availability, aiding bioprocess optimization for industrial applications of surfactin and potentially other non-ribosomal peptides. [ABSTRACT FROM AUTHOR]

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Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Endocrine disrupting chemicals (EDCs) as benzene phenolic derivatives being hydrophobic partition to organic matter in sludge/soil sediments and show slow degradation rate owing to poor bioavailability to microbes. Methods: In the present study, the potential of a versatile white rot fungal isolate S5 identified as Hypocrea lixii was monitored to degrade bisphenol A (BPA)/triclosan (TCS) under shake flask conditions with concomitant production of lipopeptide biosurfactant (BS) and plant growth promotion. Results: Sufficient growth of WRF for 5 days before supplementation of 50 ppm EDC (BPA/TCS) in set B showed an increase in degradation rates by 23% and 29% with corresponding increase in secretion of lignin-modifying enzymes compared to set A wherein almost 84% and 97% inhibition in fungal growth was observed when BPA/TCS were added at time of fungal inoculation. Further in set B, EDC concentration stimulated expression of laccase and lignin peroxidase (Lip) with 24.44 U/L of laccase and 281.69 U/L of Lip in 100 ppm BPA and 344 U/L Lip in 50 ppm TCS supplemented medium compared to their respective controls (without EDC). Biodegradation was also found to be correlated with lowering of surface tension from 57.02 mN/m (uninoculated control) to 44.16 mN/m in case of BPA and 38.49 mN/m in TCS, indicative of biosurfactant (BS) production. FTIR, GC-MS, and LC-ESI/MSMS confirmed the presence of surfactin lipopeptide isoforms. The WRF also displayed positive plant growth promoting traits as production of ammonia, indole acetic acid, siderophores, Zn solubilization, and 1-1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, reflecting its soil restoration ability. Discussion: The combined traits of biosurfactant production, EDC degradation and plant growth promotion displayed by WRF will help in emulsifying the hydrophobic pollutants favoring their fast degradation along with restoration of contaminated soil in natural conditions. [ABSTRACT FROM AUTHOR]

Surfactin is a natural surfactant almost exclusively produced by Bacillus species with excellent physical‐chemical, and biological properties. Among innovative applications, surfactin has been recently used as an ingredient in formulations. The antibacterial and anti‐acne activities, as well as the anti‐wrinkle, moisturizing, and cleansing features, are some of the reasons this lipopeptide is used in cosmetics. Considering the importance of biosurfactants in the world economy and sustainability, their potential properties for cosmetic and dermatological products, and the importance of patents for technological advancement in a circular bioeconomy system, the present study aims to review all patents involving surfactin as an ingredient in cosmetic formulas. This review was conducted through Espacenet, wherein patents containing the terms "cosmetic" and "surfactin" in their titles, abstracts, or claims were examined. Those patents that detailed a specific surfactin dosage within their formulations were selected for analysis. All patents, irrespective of their publication date, from October 1989 to December 2022, were considered. Additionally, a comprehensive search was performed in the MEDLINE and EMBASE databases, spanning from their inception until the year 2023. This complementary search aimed to enrich the understanding derived from patents, with a specific emphasis on surfactin, encompassing its associated advantages, efficacy, mechanisms of action on the skin, as well as aspects related to sustainability and its merits in cosmetic formulations. From the 105 patents analysed, 75% belong to Japan (54), China (14), and Korea (9). Most of them were submitted by Asian companies such as Showa Denko (15), Kaneka (11) and Kao Corporation (5). The formulations described are mainly emulsions, skincare, cleansing, and haircare, and the surfactin dose does not exceed 5%. Surfactin appears in different types of formulas worldwide and has a high tendency to be used. Surfactin and other biosurfactants are a promising alternative to chemical ingredients in cosmetic formulations, guaranteeing skin health benefits and minimizing the impact on the environment. [ABSTRACT FROM AUTHOR]

The emergence of multidrug-resistant fungi Candida auris is a worldwide health crisis connected with high rates of mortality. There is a critical need to find novel and unique antifungal compounds for treating infections of multidrug-resistant fungi such as C. auris. This study aimed to illustrate that biosynthetic gene clusters in native bacterial isolates are able to produce antifungal compounds against the multidrug-resistant fungus C. auris. It was successfully achieved using large-scale antifungal activity screening, cytotoxicity analysis, and whole genome sequencing integrated with genome mining-guided analysis and liquid chromatography–mass spectrometry (LC/MS). A list of possible gene candidates was initially identified with genome mining methods to predict secondary metabolite gene clusters of antifungal-compound-producing bacteria. Then, gene clusters present in the antifungal-compound-producing bacteria were identified and aligned with the reference genome using comparative genomic approaches. Bacillus halotolerans AQ11M9 was identified through large-scale antifungal activity screening as a natural compound-producer against multidrug-resistant C. auris, while it was nontoxic to normal human skin fibroblast cells (confirmed using a cell viability assay). The genome (4,197,347 bp) of B. halotolerans AQ11M9 with 2931 predicted genes was first mined for detecting and characterizing biosynthetic gene clusters, which revealed 10 candidate regions with antifungal activity. Clusters of AQ11M9 encoded non-ribosomal peptide synthase (NRPS) (bacilysin, bacillibactin, paenibactin, surfactin, plipastin, and fengycin) and polyketide (macrobrevin). The presence of gene clusters with anti-C. auris activity, and surfactin identified through LC/MS, from AQ11M9 suggests the potential of utilizing it as a source for a novel and powerful anti-C. auris compound. [ABSTRACT FROM AUTHOR]

IntroductionSurfactins, a class of lipopeptide biosurfactants secreted by plant growth-promoting rhizobacteria (PGPR), have garnered significant attention due to their dual functionality in promoting plant growth and controlling plant diseases. Their potential as biopesticides is underscored by their unique physicochemical properties and biological activities. However, the practical application of surfactin is currently limited by its low yield in natural strains.MethodsThis study aimed to optimize the culture conditions for Bacillus velezensis BN, a strain with exceptional biocontrol properties, to enhance its surfactin yield. Critical factors, including nitrogen sources and amino acid supplementation, were systematically investigated to determine their impact on surfactin production.ResultsThe study revealed that nitrogen sources and amino acid supplementation were pivotal factors influencing surfactin yield. Compared to the baseline, these factors resulted in a remarkable 5.94-fold increase in surfactin production. Furthermore, a positive correlation was established between surfactin yield and biocontrol efficacy. Enhanced surfactin yield was associated with improved antifungal activity, biofilm formation, and rhizosphere colonization capacity of B. velezensis BN on potato plantlets.DiscussionThese findings provide novel insights into the practical application of surfactin and establish a scientific foundation for the development of innovative and eco-friendly antifungal agents suitable for agricultural use. The results demonstrate that optimizing culture conditions can significantly enhance surfactin yield and biocontrol efficacy, thereby highlighting the potential for sustainable agricultural practices.