In vitro and in  vivo efficacy of Caenorhabditis elegans recombinant antimicrobial protein against Gram-negative bacteria.
This study reports how the C. elegans recombinant antibacterial factor (ABF-1) rapidly inhibited bacterial growth (Salmonella Typhi, Klebsiella pneumonia, Shigella sonnei and Vibrio alginolyticus). The ABF-1 exposure on S. Typhi, showed differential regulation in cell-cycle, DNA repair mechanism, membrane stability, and stress related proteins. The exogenous supply of ABF-1 protein has extended C. elegans survival by reducing the bacterial colony forming units on the nematode intestine. Together, these findings indicate the valuable and potential therapeutic applications of ABF-1 protein as antimicrobial agents against int...
Source: Biofouling - October 16, 2019 Category: Molecular Biology Authors: Mir DA, Balamurugan K Tags: Biofouling Source Type: research

Profiling the microbial contamination in aviation fuel from an airport.
In this study, culture-based combing with the culture-independent methods, were used to profile the microbial contamination in aviation fuel. High-throughput sequencing (HTS) modified by propidium monoazide (PMA) revealed a higher diversity of contaminating microorganisms in samples than the culture method. Proteobacteria (47%), Actinobacteria (21%) and Ascomycota (>99%, fungi) were the most abundant phyla, and the neglected archaea was also detected. Additionally, qPCR-based methods revealed all samples contained a heavy level of microbial contamination, which was more accurate than its culturable counterparts, and fun...
Source: Biofouling - October 11, 2019 Category: Molecular Biology Authors: Hu D, Lin W, Zeng J, Wu P, Zhang M, Guo L, Ye C, Wan K, Yu X Tags: Biofouling Source Type: research

Marine biofilm bacterial community response and carbon steel loss following Deepwater Horizon spill contaminant exposure.
Abstract Steel marine structures provide foci of biodiversity when they develop into artificial reefs. Development begins with deposition of a biofilm. The effects of contaminants from oil spills on biofilm microbiomes, microbially-induced corrosion (MIC) and metal loss may impact preservation of marine metal structures. A microcosm experiment exposed biofilms on carbon steel disks (CSDs) to crude oil, dispersant, and dispersed oil to address their impacts on bacterial composition and metal loss and pitting. Biofilm diversity increased over time in all exposures. Community composition in dispersant and dispersed o...
Source: Biofouling - October 11, 2019 Category: Molecular Biology Authors: Mugge RL, Lee JS, Brown TT, Hamdan LJ Tags: Biofouling Source Type: research

A data-driven approach to predicting the attachment density of biofouling organisms.
Abstract The attachment efficiency of biofouling organisms on solid surfaces depends on a variety of factors, including fouler species, nutrition abundance, flow rate, surface morphology and the stiffness of the solid to which attachment is to be made. So far, extensive research has been carried out to investigate the effects of these factors on the attachment of various fouling species. However, the results obtained are species-dependent and scattered. There is no universal rule that can be applied to predict the attachment efficiency of different species. To solve this problem, the authors carried out meta-analy...
Source: Biofouling - October 1, 2019 Category: Molecular Biology Authors: Vellwock AE, Fu J, Meng Y, Thiyagarajan V, Yao H Tags: Biofouling Source Type: research

Multispecies biofilm formation by the contaminating microbiota in raw milk.
This study evaluated the diversity of multispecies biofilms formed on stainless steel (SS) due to the contaminating microbiota in raw milk. Samples of raw milk were used: one was fresh milk and the other maintained in refrigerated bulk tanks for up to 48 h. The mesophilic aerobic contamination was ∼104 CFU ml-1 in fresh milk and 106 CFU ml-1 in bulk milk. SS coupons were kept immersed in the milk at 7 ±2 °C for 10 days, and every two days, the raw milk was changed for samples of the same origin collected on the current day. After incubation for 10 days, sessile cells in the biofilm reached 105 CFU cm-2 in th...
Source: Biofouling - September 26, 2019 Category: Molecular Biology Authors: Oliveira GS, Lopes DRG, Andre C, Silva CC, Baglinière F, Vanetti MCD Tags: Biofouling Source Type: research

In situ characterisation of biofilms formed by psychrotrophic meat spoilage pseudomonads.
Abstract Psychrotrophic Pseudomonas species form biofilms on meat during refrigerated and temperature abuse conditions. Biofilm growth leads to slime formation on meat which is a key organoleptic degradation characteristic. Limited research has been undertaken characterising biofilms grown on meat during chilled aerobic storage. In this work, biofilms formed by two key meat spoilage organisms, Pseudomonas fragi and Pseudomonas lundensis were studied in situ using five strains from each species. Biofilm structures were studied using confocal microscope images, cellular arrangement, cell counts and biomass quantific...
Source: Biofouling - September 26, 2019 Category: Molecular Biology Authors: Wickramasinghe NN, Ravensdale JT, Coorey R, Dykes GA, Scott Chandry P Tags: Biofouling Source Type: research

Testing of novel net cleaning technologies for finfish aquaculture.
This study examined low-pressure-, cavitation-, and suction-based cleaning technologies as alternatives to conventional high-pressure cleaning. Using field experiments, cleaning efficacy, cleaning waste generation, and the impact of cleaning on coating integrity and net strength were evaluated. Cavitation and high-pressure cleaning achieved considerably higher cleaning efficacy than low-pressure and suction cleaning. However, a single high-pressure treatment caused up to 53% coating degradation, compared to 2% for cavitation. All technologies produced similar cleaning waste and neither reduced net strength significantly. T...
Source: Biofouling - September 20, 2019 Category: Molecular Biology Authors: Bloecher N, Frank K, Bondø M, Ribicic D, Endresen PC, Su B, Floerl O Tags: Biofouling Source Type: research

Portraying manganese biofilms via a merger of EPR spectroscopy and cathodic polarization.
Abstract Microbial biofilms on stainless steel surfaces exposed to water from a freshwater pond were dominated by manganese-oxidizing bacteria, as initially diagnosed by microscopy and elemental analysis. The application of electron paramagnetic resonance (EPR) spectroscopy revealed conspicuous sextet (six-line) patterns that intensified with immersion time, implying the gradual accumulation of Mn(II) in the biofilms. Correspondingly, cathodic polarization designated the manganese oxide (MnOx) reduction peak in the form of a distinctive 'nose', which grew increasingly more negative with biofilm growth. The progres...
Source: Biofouling - September 18, 2019 Category: Molecular Biology Authors: Lakshman Kumar A, Eashwar M, Sreedhar G, Vengatesan S, Prabu V, Shanmugam VM Tags: Biofouling Source Type: research

Effect of commercial herbal toothpastes and mouth rinses on the prevention of enamel demineralization using a microcosm biofilm model.
tilde;es AC Abstract This work evaluated the effects of commercial toothpastes and mouth rinses containing natural/herbal agents on biofilm viability, extracellular polysaccharide (EPS) production and on enamel demineralization in vitro. Microcosm biofilm was produced on bovine enamel for 5 days and treated daily with: Orgânico natural® (toothpaste/mouth rinse), Boni Natural Menta & Malaleuca® (toothpaste/mouth rinse), Propolis & Myrrh® (toothpaste), Colgate Total 12 Clean Mint® (toothpaste, positive control), Malvatricin® Plus (mouth rinse), PerioGard® (mouth rinse, po...
Source: Biofouling - September 13, 2019 Category: Molecular Biology Authors: Braga AS, Girotti LD, de Melo Simas LL, Pires JG, Pelá VT, Buzalaf MAR, Magalhães AC Tags: Biofouling Source Type: research

The effective photocatalysis and antibacterial properties of AgBr/Ag2MoO4@ZnO composites under visible light irradiation.
Abstract A novel Z-scheme AgBr/Ag2MoO4@ZnO photocatalyst was fabricated via a hydrothermal process and in situ growth method. X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy were used to determine the structure of the photocatalyst. The results showed that the composites were tightly connected by the (101) lattice plane of ZnO, the (222) plane of Ag2MoO4 and the (200) lattice plane of AgBr. Because of the strong redox activity and good separability of photoelectrons and holes induced by the Z-scheme structure, the photodegradation rate for ciprofloxacin (CIP) solution wa...
Source: Biofouling - September 10, 2019 Category: Molecular Biology Authors: Xu H, Zhang J, Lv X, Niu T, Zeng Y, Duan J, Hou B Tags: Biofouling Source Type: research

The anti-biofilm and anti-virulence activities of trans-resveratrol and oxyresveratrol against uropathogenic Escherichia coli.
In this study, the anti-biofilm activities of t-stilbene, stilbestrol, t-resveratrol, oxyresveratrol, ε-viniferin, suffruticosol A, and vitisin A were investigated against UPEC. t-Resveratrol, oxyresveratrol, and ε-viniferin, suffruticosol A, and vitisin A significantly inhibited UPEC biofilm formation at subinhibitory concentrations (10-50 μg ml-1). These findings were supported by observations that t-resveratrol and oxyresveratrol reduced fimbriae production and the swarming motility in UPEC. Furthermore, t-resveratrol and oxyresveratrol markedly diminished the hemagglutinating ability of UPEC, ...
Source: Biofouling - September 10, 2019 Category: Molecular Biology Authors: Lee JH, Kim YG, Raorane CJ, Ryu SY, Shim JJ, Lee J Tags: Biofouling Source Type: research

Interfacial water and its potential role in the function of sericin against biofouling.
ck GH Abstract Silk sericin is a globular protein whose resistance against fouling is important for applications in biomaterials and water-purification membranes. Here it is shown how sericin generates a water-exclusion zone that may facilitate antifouling behavior. Negatively charged microspheres were used to mimic the surface charge and hydrophobic domains in bacteria. Immersed in water, regenerated silk sericin formed a 100-µm-sized exclusion zone (for micron-size foulants), along with a proton gradient with a decrease of>2 pH-units. Thus, when in contact with sericin, water molecules near the s...
Source: Biofouling - August 30, 2019 Category: Molecular Biology Authors: Pedregal-Cortés R, Toriz G, Delgado E, Pollack GH Tags: Biofouling Source Type: research

Activity of sodium trimetaphosphate, associated or not with fluoride, on dual-species biofilms.
This study aimed to evaluate the effect of sodium trimetaphosphate (TMP), either with fluoride (F) or without fluoride, on dual-species biofilms of Streptococcus mutans and Candida albicans. The 72 h biofilms were treated with 0.25%, 0.5%, or 1% TMP solutions, combined or not with 500 ppm F, and analysed by quantification of viable plate counts, metabolic activity, biomass, and extracellular matrix components. Biofilm structure was evaluated by scanning electron microscopy (SEM). TMP significantly reduced the number of S. mutans cells and biomass only when associated to F. Furthermore, fluoride-free TMP promo...
Source: Biofouling - August 27, 2019 Category: Molecular Biology Authors: Cavazana TP, Hosida TY, Pessan JP, Sampaio C, Monteiro DR, Delbem ACB Tags: Biofouling Source Type: research

Dynamics of a biofouling community in finfish aquaculture: a case study from the South Adriatic Sea.
Abstract Biofouling is one of the challenges that can strongly affect the finfish farm economy. Although several studies on biofouling in aquaculture have been conducted in the Mediterranean Sea, they focused on specific taxa or were limited to a particular period of sampling. The present study investigated for the first time the development, composition and variation in a biofouling community in a finfish farm with immersion time, season and depth. The results indicate that all these factors influence biofouling succession and recruitment. Moreover, the species that had a crucial role in structuring the community...
Source: Biofouling - August 23, 2019 Category: Molecular Biology Authors: Pica D, Bloecher N, Dell'Anno A, Bellucci A, Pinto T, Pola L, Puce S Tags: Biofouling Source Type: research

Effects of inter-organism interactions in biofouling on microtopographic surfaces.
Abstract An extended model of the surface energetic attachment (SEA) model is introduced to study the fouling of marine organisms on microtopographic surfaces, taking into account the excluded volume interaction and the attraction between the organisms. It is shown that the excluded volume interaction leads to changes in the site-typed attachment probabilities which increase with the average spore density on the surface. As a result of these changes, the spore density map is flattened under very high density fouling. The attractive interaction on the other hand leads to aggregation of spores and the average aggreg...
Source: Biofouling - August 20, 2019 Category: Molecular Biology Authors: Hoang TX, Mai HTH, Brennan AB, Le L Tags: Biofouling Source Type: research

Bulk phase resource ratio alters carbon steel corrosion rates and endogenously produced extracellular electron transfer mediators in a sulfate-reducing biofilm.
Abstract Desulfovibrio alaskensis G20 biofilms were cultivated on 316 steel, 1018 steel, or borosilicate glass under steady-state conditions in electron-acceptor limiting (EAL) and electron-donor limiting (EDL) conditions with lactate and sulfate in a defined medium. Increased corrosion was observed on 1018 steel under EDL conditions compared to 316 steel, and biofilms on 1018 carbon steel under the EDL condition had at least twofold higher corrosion rates compared to the EAL condition. Protecting the 1018 metal coupon from biofilm colonization significantly reduced corrosion, suggesting that the corrosion mechani...
Source: Biofouling - August 11, 2019 Category: Molecular Biology Authors: Krantz GP, Lucas K, Wunderlich EL, Hoang LT, Avci R, Siuzdak G, Fields MW Tags: Biofouling Source Type: research

Control of biofouling on pearl oysters Pinctada imbricata using wax and Chinese herbs.
Abstract Biofouling poses severe challenges to pearl oyster Pinctada imbricata culture in China, and controlling it is both labor- and capital-intensive. The antifouling properties of wax, and wax mixed with Chinese herbs, sprayed onto pearl oyster shell surfaces during peak biofouling seasons were evaluated. Pearl oysters coated with three wax treatments (plain wax, Chinaberry seed extract, Chinese honeylocust fruit extract) and a control (no treatment), were cultured in nets for up to 60 days. Mortality rate, fouling organism and pearl-oyster weights, and shell height are reported for individual oysters o...
Source: Biofouling - August 1, 2019 Category: Molecular Biology Authors: Ye L, Wu L, Wang Z, Jiang J, Wang J Tags: Biofouling Source Type: research

Biofouling in marine aquaculture: a review of recent research and developments.
Abstract Biofouling in marine aquaculture is one of the main barriers to efficient and sustainable production. Owing to the growth of aquaculture globally, it is pertinent to update previous reviews to inform management and guide future research. Here, the authors highlight recent research and developments on the impacts, prevention and control of biofouling in shellfish, finfish and seaweed aquaculture, and the significant gaps that still exist in aquaculturalists' capacity to manage it. Antifouling methods are being explored and developed; these are centred on harnessing naturally occurring antifouling propertie...
Source: Biofouling - July 24, 2019 Category: Molecular Biology Authors: Bannister J, Sievers M, Bush F, Bloecher N Tags: Biofouling Source Type: research

Effect of aeration rate on the anti-biofouling properties of cellulose acetate nanocomposite membranes in a membrane bioreactor system for the treatment of pharmaceutical wastewater.
In this study, the effect of aeration rate in terms of specific aeration demand per membrane area (SADm) on the anti-biofouling properties of cellulose acetate (CA) nanocomposite membranes (CA/ND-NH2) in a membrane bioreactor system was investigated. The amount of EPS and soluble EPS under high aeration rate conditions was observed to be higher than under low aeration rate conditions. The results obtained showed that either lower or higher aeration rates had a negative impact on membrane permeability. The high aeration rate resulted in a severe breakage of sludge flocs, and promoted the release of soluble EPS from the micr...
Source: Biofouling - July 16, 2019 Category: Molecular Biology Authors: Etemadi H, Yegani R Tags: Biofouling Source Type: research

Effects of surface texture and interrelated properties on marine biofouling: a systematic review.
Abstract This systematic review examines effects of surface texture on marine biofouling and characterizes key research methodologies. Seventy-five published articles met selection criteria for qualitative analysis; experimental data from 36 underwent quantitative meta-analysis. Most studies investigated fouling mechanisms and antifouling performance only in laboratory assays with one to several test species. Textures were almost exclusively a single layer of regularly arranged geometric features rather than complex hierarchical or irregular designs. Textures in general had no effect or an inconclusive effect on f...
Source: Biofouling - July 12, 2019 Category: Molecular Biology Authors: Carve M, Scardino A, Shimeta J Tags: Biofouling Source Type: research

Terpinen-4-ol and carvacrol affect multi-species biofilm composition.
In conclusion, specific concentrations of T4ol and carvacrol without toxicity towards the epithelial cells reduced the numbers of periodontal pathogens in single- and multi-species biofilms. PMID: 31282200 [PubMed - as supplied by publisher] (Source: Biofouling)
Source: Biofouling - July 8, 2019 Category: Molecular Biology Authors: Maquera Huacho PM, Rodriguez Herrero E, Verspecht T, Pauwels M, Marcantonio E, Palomari Spolidorio DM, Teughels W Tags: Biofouling Source Type: research

D-LL-31 in combination with ceftazidime synergistically enhances bactericidal activity and biofilm destruction in Burkholderia pseudomallei.
Abstract Melioidosis is a severe disease caused by Burkholderia pseudomallei. The biofilm of B. pseudomallei acquires resistance to several antibiotics and may be related to relapse in melioidosis patients. Here, the killing activity of antimicrobial peptides (LL-37, LL-31) and the D-enantiomers (D-LL-37, D-LL-31) in combination with ceftazidime (CAZ) against B. pseudomallei 1026b, H777 and a biofilm mutant M10, derived from H777 grown under biofilm-stimulating conditions was observed. Using static conditions, D-LL-31 exhibited the strongest killing activity against the three isolates in a dose-dependent manner. I...
Source: Biofouling - July 8, 2019 Category: Molecular Biology Authors: Wongkaewkhiaw S, Taweechaisupapong S, Anutrakunchai C, Nazmi K, Bolscher JGM, Wongratanacheewin S, Kanthawong S Tags: Biofouling Source Type: research

The oceans are changing: impact of ocean warming and acidification on biofouling communities.
Abstract Climate change (CC) is driving modification of the chemical and physical properties of estuaries and oceans with profound consequences for species and ecosystems. Numerous studies investigate CC effects from species to ecosystem levels, but little is known of the impacts on biofilm communities and on bioactive molecules such as cues, adhesives and enzymes. CC is induced by anthropogenic activity increasing greenhouse emissions leading to rises in air and water temperatures, ocean acidification, sea level rise and changes in ocean gyres and rainfall patterns. These environmental changes are resulting in al...
Source: Biofouling - July 8, 2019 Category: Molecular Biology Authors: Dobretsov S, Coutinho R, Rittschof D, Salta M, Ragazzola F, Hellio C Tags: Biofouling Source Type: research

Anoxybacillus and Geobacillus biofilms in the dairy industry: effects of surface material, incubation temperature and milk type.
This study proposes that the surface material, temperature and milk type had a cumulative effect on biofilm formation. PMID: 31273998 [PubMed - as supplied by publisher] (Source: Biofouling)
Source: Biofouling - July 5, 2019 Category: Molecular Biology Authors: Karaca B, Buzrul S, Coleri Cihan A Tags: Biofouling Source Type: research

A putative LysR-type transcriptional regulator inhibits biofilm synthesis in Pseudomonas aeruginosa.
Abstract Biofilm formation is an important virulence factor which is controlled by complex regulatory circuits in Pseudomonas aeruginosa. In this work, a biofilm hyper-producing strain, P2-7, was selected from a collection of transposon insertion mutants in which the PA2121 gene was disrupted. PA2121 was predicted as a putative LysR-type regulator. Analyses showed that it was involved in early biofilm formation, mature biofilm development, and colony morphology. Quantitative measurements revealed that PA2121 repressed biosynthesis of extracellular polysaccharides (alginate, psl and pel). Furthermore, it was observ...
Source: Biofouling - July 4, 2019 Category: Molecular Biology Authors: Yang X, Zhang Z, Huang Z, Zhang X, Li D, Sun L, You J, Pan X, Yang H Tags: Biofouling Source Type: research

Short-term succession of marine microbial fouling communities and the identification of primary and secondary colonizers.
This study was undertaken to follow temporal shifts in biofouling communities in order to identify primary and secondary colonizers. Quantitative analysis revealed a significant increase in total biomass, coverage of macrofoulers, chlorophyll a concentrations, and bacterial counts with time. The relative abundance of the adnate diatoms increased with time, whereas it decreased in the case of the plocon diatoms. Non-metric multidimensional scaling (NMDS) ordination based on MiSeq data placed the bacterial communities in three distinct clusters, depending on the time of sampling. While the relative abundance of Alphaproteoba...
Source: Biofouling - June 20, 2019 Category: Molecular Biology Authors: Abed RMM, Al Fahdi D, Muthukrishnan T Tags: Biofouling Source Type: research

In situ spectroscopic analysis of Lactobacillus rhamnosus GG flow on an abiotic surface reveals a role for nutrients in biofilm development.
e;s F Abstract In this work, infrared spectroscopy was used to monitor the changes in the biochemical composition of biofilms of the probiotic bacterium Lactobacillus rhamnosus GG (LGG) in three nutritive media (10-fold diluted MRS, AOAC, and mTSB), in situ and under flow conditions. Epifluorescence microscopy was used to observe the shape of LGG cells and their distribution on the surface. Spectroscopic fingerprints recorded as a function of time revealed a medium-dependent content of nucleic acids, phospholipids and polysaccharides in the biofilms. In addition, time-dependent synthesis of lactic acid was observe...
Source: Biofouling - June 10, 2019 Category: Molecular Biology Authors: Yunda E, Quilès F Tags: Biofouling Source Type: research

Periodic ultraviolet-C illumination for marine sensor antifouling.
This study field-tested the effects of periodic ultraviolet-C illumination on marine macrofouling. Across four experiments, several UV illumination duty cycles were tested against controls with no illumination. Duty cycles between 1:2 (time with UV:total time per cycle) and 1:20 were all similarly effective, inhibiting almost all macrofouling at three different temperate Northeast Pacific and Northwest Atlantic sites. Susceptible taxa included barnacles, bryozoans, tunicates (colonial and solitary), and, to a slightly lesser extent, mussels. Duty cycles of 1:30 and 1:60 reduced but did not eliminate biofouling. Measurement...
Source: Biofouling - June 10, 2019 Category: Molecular Biology Authors: MacKenzie AF, Maltby EA, Harper N, Bueley C, Olender D, Wyeth RC Tags: Biofouling Source Type: research

Ex vivo biofilm-forming ability of dermatophytes using dog and cat hair: an ethically viable approach for an infection model.
Branco DSCM Abstract The aim of this study was to establish an ex vivo model for dermatophyte biofilm growth, using hair from dogs and cats. Strains of Microsporum canis, M. gypseum, Trichophyton mentagrophytes and T. tonsurans were assessed for in vitro and ex vivo biofilm production. All T. mentagrophytes and T. tonsurans isolates and 8/12 M. canis and 1/7 M. gypseum isolates formed biofilms in vitro, while all tested isolates presented biofilm growth on ex vivo models. T. mentagrophytes and M. canis formed more homogeneous and better-structured biofilms with greater biomass production on cat hair ...
Source: Biofouling - June 2, 2019 Category: Molecular Biology Authors: Brilhante RSN, Aguiar L, Sales JA, Araújo GDS, Pereira VS, Pereira-Neto WA, Pinheiro AQ, Paixão GC, Cordeiro RA, Sidrim JJC, Bersano PRO, Rocha MFG, Castelo-Branco DSCM Tags: Biofouling Source Type: research

The complex barnacle perfume: identification of waterborne pheromone homologues in Balanus improvisus and their differential expression during settlement.
This study aimed to identify WSP homologues in Balanus improvisus and to investigate their expression during settlement. Six WSP homologues were identified, all containing an N-terminal signal peptide, a conserved core region, and a variable C-terminus comprising several -GR- and -HDDH- motifs. The B. improvisus WSP homologues were expressed in all settlement stages but showed different expression patterns. The homologue most similar to the B. amphitrite WSP was the most abundant and was constantly expressed during settlement. In contrast, several of the other WSP homologues showed the greatest expression in the juvenile s...
Source: Biofouling - May 30, 2019 Category: Molecular Biology Authors: Abramova A, Lind U, Blomberg A, Rosenblad MA Tags: Biofouling Source Type: research

The influence of chlorination timing and concentration on microbial communities in labyrinth channels: implications for biofilm removal.
In this study, the dynamic of microbial communities was examined under different residual chlorine concentrations on the biofilms attached to labyrinth channels for drip irrigation using reclaimed water. The results indicated that the microbial phospholipid fatty acids, extracellular polymeric substances, microbial dynamics, and the ace and Shannon microbial diversity indices showed a gradual decrease after chlorination. However, chlorination increased microbial activity by 0.5-19.2%. The increase in the relative abundances of chloride-resistant bacteria (Acinetobacter and Thermomonas) could lead to a potential risk of chl...
Source: Biofouling - May 30, 2019 Category: Molecular Biology Authors: Song P, Zhou B, Feng G, Brooks JP, Zhou H, Zhao Z, Liu Y, Li Y Tags: Biofouling Source Type: research

Mini-review: efficacy of lytic bacteriophages on multispecies biofilms.
Abstract There is potential for phages to prevent and control bacterial biofilms, but few studies have examined the effect of phages on the multispecies biofilms that characterize most bacterial infections. This paper reviews the mechanism of action of phages, the evidence supporting the view that phage therapy will be effective against bacterial targets and the opposite viewpoint, phage application approaches, and the comparative advantage of phage therapy in multispecies biofilms. The few reports measuring the actions of lytic phages against multispecies biofilms are also reviewed. The authors are cautiously opt...
Source: Biofouling - May 30, 2019 Category: Molecular Biology Authors: Geredew Kifelew L, Mitchell JG, Speck P Tags: Biofouling Source Type: research

Virulence targeted inhibitory effect of linalool against the exclusive uropathogen Proteus mirabilis.
In this study, linalool exhibited concentration dependent anti-biofilm activity against crystalline biofilm of P. mirabilis through reduced production of the virulence enzyme urease that raises the urinary pH and drives the formation of crystals (struvite) in the biofilm. The results of q-PCR analysis unveiled the down regulation of biofilm/virulence associated genes upon linalool treatment, which was in correspondence with the in vitro bioassays. Thus, this study reports the feasibility of linalool acting as a promising anti-biofilm agent against P. mirabilis mediated CAUTI. PMID: 31144520 [PubMed - as supplied by pu...
Source: Biofouling - May 30, 2019 Category: Molecular Biology Authors: Durgadevi R, Veera Ravi A, Alexpandi R, Krishnan Swetha T, Abirami G, Vishnu S, Karutha Pandian S Tags: Biofouling Source Type: research

Plume height and surface coverage analysis of methicillin-resistant Staphylococcus aureus isolates grown in a CDC biofilm reactor.
In this study, three strains of methicillin-resistant Staphylococcus aureus (MRSA) (USA300, USA400 and a clinical isolate) were grown in brain heart infusion broth (BHI) or tryptic soy broth (TSB). Following growth, SEM images were captured for 3-D analysis to assess plume height. TSB produced significantly higher plume heights of USA300 and USA400 compared to BHI. Broth type was less influential on the clinical isolate. The data indicate that broth type and time may be important factors to consider when assessing maturation and plume height formation of MRSA biofilms. PMID: 31144524 [PubMed - as supplied by publisher...
Source: Biofouling - May 30, 2019 Category: Molecular Biology Authors: Rasmussen RM, Epperson RT, Taylor NB, Williams DL Tags: Biofouling Source Type: research

Ecological role of Acinetobacter calcoaceticus GSN3 in natural biofilm formation and its advantages in bioremediation.
This study assessed the role of a new Acinetobacter calcoaceticus strain, GSN3, with biofilm-forming and phenol-degrading abilities. Three biofilm reactors were spiked with activated sludge (R1), green fluorescent plasmid (GFP) tagged GSN3 (R2), and their combination (R3). More than 99% phenol removal was achieved during four weeks in R3 while this efficiency was reached after two and four further operational weeks in R2 and R1, respectively. Confocal scanning electron microscopy revealed that GSN3-gfp strains appeared mostly in the deeper layers of the biofilm in R3. After four weeks, almost 7.07 &tim...
Source: Biofouling - May 23, 2019 Category: Molecular Biology Authors: Irankhah S, Abdi Ali A, Mallavarapu M, Soudi MR, Subashchandrabose S, Gharavi S, Ayati B Tags: Biofouling Source Type: research

Analysis of marine microbial communities colonizing various metallic materials and rust layers.
Abstract High-throughput sequencing was used to visualize microbial biocoenoses on different metallic surfaces and rust layers of highly corroded steels after immersion in coastal marine water for 30 months at Sanya, China. Distinct microbial community compositions were observed on these metallic surfaces. The dominant genus was the copper-tolerant, acid-producing Lactobacillus on copper alloys, the common aerobic surface colonizers Bacillus and Ruegeria on aluminum alloys, and aerobic biofilm-forming Pseudomonas on carbon steel. Most of these are copiotrophic microbes compared to planktonic microbes, which are ol...
Source: Biofouling - May 20, 2019 Category: Molecular Biology Authors: Zhang Y, Ma Y, Duan J, Li X, Wang J, Hou B Tags: Biofouling Source Type: research

Sediment challenge to promising ultra-low fouling hydrophilic surfaces in the marine environment.
n A Abstract Hydrophilic coatings exhibit ultra-low fouling properties in numerous laboratory experiments. In stark contrast, the antifouling effect of such coatings in vitro failed when performing field tests in the marine environment. The fouling release performance of nonionic and zwitterionic hydrophilic polymers was substantially reduced compared to the controlled laboratory environment. Microscopy and spectroscopy revealed that a large proportion of the accumulated material in field tests contains inorganic compounds and diatomaceous soil. Diatoms adhered to the accumulated material on the coating, but not t...
Source: Biofouling - May 15, 2019 Category: Molecular Biology Authors: Koc J, Simovich T, Schönemann E, Chilkoti A, Gardner H, Swain GW, Hunsucker K, Laschewsky A, Rosenhahn A Tags: Biofouling Source Type: research

Quorum sensing: an emerging link between temperature and membrane biofouling in membrane bioreactors.
Abstract Lab-scale membrane bioreactors (MBRs) were investigated at 12, 18, and 25 °C to identify the correlation between quorum sensing (QS) and biofouling at different temperatures. The lower the reactor temperature, the more severe the membrane biofouling measured in terms of the transmembrane pressure (TMP) during filtration. More extracellular polymeric substances (EPSs) that cause biofouling were produced at 18 °C than at 25 °C, particularly polysaccharides, closely associated with QS via the production of N-acyl homoserine lactone (AHL). However, at 12 °C, AHL pro...
Source: Biofouling - May 15, 2019 Category: Molecular Biology Authors: Nahm CH, Kim K, Min S, Lee H, Chae D, Lee K, Choo KH, Lee CH, Koyuncu I, Park PK Tags: Biofouling Source Type: research

Candida albicans enhances initial biofilm growth of Cutibacterium acnes under aerobic conditions.
The objective of this study was to evaluate the ability of these species to interact and form polymicrobial biofilms. SEM imaging and adhesion assays showed that C. acnes adhesion to C. albicans did not have a preference for a specific morphological state of C. albicans; bacteria adhered to both hyphal and yeast forms of C. albicans. C. albicans did not influence growth of C. acnes under anaerobic growth conditions, however under aerobic growth condition, C. albicans enhanced early C. acnes biofilm formation. This favorable impact of C. albicans was not mediated by secreted compounds accumulating in the medium, but require...
Source: Biofouling - May 14, 2019 Category: Molecular Biology Authors: Bernard C, Lemoine V, Hoogenkamp MA, Girardot M, Krom BP, Imbert C Tags: Biofouling Source Type: research

Anti-biofilm activities of essential oils rich in carvacrol and thymol against Salmonella Enteritidis.
This study revealed that the EO's and EOC's (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO's and EOC's in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO's and EOC's (the essential oil components, carvacrol and thymol) on eradication of preformed 48 h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time. PMID: 31088182 [PubMed - as s...
Source: Biofouling - May 14, 2019 Category: Molecular Biology Authors: Čabarkapa I, Čolović R, Đuragić O, Popović S, Kokić B, Milanov D, Pezo L Tags: Biofouling Source Type: research

Upregulation of peroxide scavenging enzymes and multidrug efflux proteins highlight an active sodium hypochlorite response in Pseudomonas fluorescens biofilms.
Abstract The oxidative biocide sodium hypochlorite is among the most commonly used antimicrobial agents in the control of surface-attached microbial communities (biofilms). Clarifying the genetic response of microorganisms in biofilms to hypochlorite may contribute to improved biofilm control strategies. Here, RNA-seq was used to investigate the differential gene expression response of industrially relevant Pseudomonas fluorescens biofilms to sub-lethal concentrations of sodium hypochlorite. Pseudomonas biofilms responded to hypochlorite exposure with increased transcription of genes encoding peroxide scavenging e...
Source: Biofouling - May 8, 2019 Category: Molecular Biology Authors: Lipus D, Vikram A, Gulliver D, Bibby K Tags: Biofouling Source Type: research

Diacetylcurcumin: a new photosensitizer for antimicrobial photodynamic therapy in Streptococcus mutans biofilms.
This study evaluated the effect of antimicrobial photodynamic therapy (aPDT) on S. mutans using diacetylcurcumin (DAC) and verified DAC toxicity. In vitro, S. mutans biofilms were exposed to curcumin (CUR) and DAC and were light-irradiated. Biofilms were collected, plated and incubated for colony counts. DAC and CUR toxicity assays were conducted with Human Gingival Fibroblast cells (HGF). In vivo, G. mellonella larvae were injected with S. mutans and treated with DAC, CUR and aPDT. The hemolymph was plated and incubated for colony counts. Significant reductions were observed when DAC and CUR alone were used and when aPDT ...
Source: Biofouling - May 8, 2019 Category: Molecular Biology Authors: Sanches CVG, Sardi JCO, Terada RSS, Lazarini JG, Freires IA, Polaquini CR, Torrezan GS, Regasini LO, Fujimaki M, Rosalen PL Tags: Biofouling Source Type: research

Antifungal effects of the flavonoids kaempferol and quercetin: a possible alternative for the control of fungal biofilms.
This study aimed to determine the minimum inhibitory concentration (MIC) of kaempferol and quercetin against planktonic and biofilm forms of the Candida parapsilosis complex. Initially, nine C. parapsilosis sensu stricto, nine C. orthopsilosis and nine C. metapsilosis strains were used. Planktonic susceptibility to kaempferol and quercetin was assessed. Growing and mature biofilms were then exposed to the flavonoids at MIC or 10xMIC, respectively, and theywere also analyzed by confocal laser scanning microscopy. The MIC ranges were 32-128 µg ml-1 for kaempferol and 0.5-16 µg ml-1 for quercetin. Kaempferol and q...
Source: Biofouling - May 8, 2019 Category: Molecular Biology Authors: Rocha MFG, Sales JA, da Rocha MG, Galdino LM, de Aguiar L, Pereira-Neto WA, de Aguiar Cordeiro R, Castelo-Branco DSCM, Sidrim JJC, Brilhante RSN Tags: Biofouling Source Type: research

Population dynamics of a dual Pseudomonas putida-Pseudomonas fluorescens biofilm in a capillary bioreactor.
Abstract Most biofilm studies employ single species, yet in nature biofilms exist as mixed cultures, with inevitable effects on growth and development of each species present. To investigate how related species of bacteria interact in biofilms, two Pseudomonas spp., Pseudomonas fluorescens and Pseudomonas putida, were cultured in capillary bioreactors and their growth measured by confocal microscopy and cell counting. When inoculated in pure culture, both bacteria formed healthy biofilms within 72 h with uniform coverage of the surface. However, when the bioreactors were inoculated with both bacteria simult...
Source: Biofouling - April 26, 2019 Category: Molecular Biology Authors: Gazzola G, Habimana O, Quinn L, Casey E, Murphy CD Tags: Biofouling Source Type: research

Biofouling of stainless steel surfaces by four common pathogens: the effects of glucose concentration, temperature and surface roughness.
Abstract There is a wide range of factors affecting bacterial adhesion and biofilm formation. However, in both food processing and medical settings, it is very hard to obtain suitably controlled conditions so that the factors that reduce surface colonisation and biofouling can be studied. The aim of this study was to evaluate the effect of glucose concentration, temperature and stainless steel (SS) surface roughness on biofouling by four common pathogens (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and L. monocytogenes). Among the tested variables, the untreated SS surface (3C) was shown to be ...
Source: Biofouling - April 26, 2019 Category: Molecular Biology Authors: Bezek K, Nipič D, Torkar KG, Oder M, Dražić G, Abram A, Žibert J, Raspor P, Bohinc K Tags: Biofouling Source Type: research

Brazilian red propolis reduces orange-complex periodontopathogens growing in multispecies biofilms.
This study investigated the antimicrobial effects of the ethanolic extract of Brazilian red propolis (BRP) on multispecies biofilms. A seven-day-old subgingival biofilm with 32 species was grown in a Calgary device. Biofilms were treated with BRP (1,600, 800, 400 and 200 μg ml-1) twice a day for 1 min, starting from day 3. Chlorhexidine (0.12%) and dilution-vehicle were used as positive and negative controls, respectively. On day 7, metabolic activity and the microbial composition of the biofilms by DNA-DNA hybridization were determined. The viability data were analyzed by one-way ANOVA followed by Tukey's...
Source: Biofouling - April 24, 2019 Category: Molecular Biology Authors: Miranda SLF, Damasceno JT, Faveri M, Figueiredo L, da Silva HD, Alencar SMA, Rosalen PL, Feres M, Bueno-Silva B Tags: Biofouling Source Type: research

Multistep approach to control microbial fouling of historic building materials by aerial phototrophs.
cki B Abstract The scientific multistep approach described herein is a result of two years of research into a control method against microbial fouling and biodeterioration of historic building materials by phototrophs. A series of tests were conducted to select the best antifouling agent for eliminating 'green' coatings and protecting surfaces against biofouling. Of the seven active compounds, two with the best penetration abilities were subjected to a photosynthetic activity inhibition test using confocal microscopy. Of the two, a quaternary ammonium salt (QAC) - didecyldimethylammonium chloride (DDAC) - was foun...
Source: Biofouling - April 23, 2019 Category: Molecular Biology Authors: Nowicka-Krawczyk P, Żelazna-Wieczorek J, Koziróg A, Otlewska A, Rajkowska K, Piotrowska M, Gutarowska B, Brycki B Tags: Biofouling Source Type: research

The role of biofouling development in the loss of seed mussels in aquaculture.
Abstract The efficient seeding of juvenile mussels is critical to the sustainability and profitability of mussel aquaculture. However, seeding mussels is highly inefficient, with many juveniles being lost in the following few months. One possible cause of these losses could be the development of biofouling assemblages. Therefore, the relationships between biofouling accumulation and losses of juveniles were assessed. Losses of juvenile mussels were initially high (42.9-49.1% over approximately one to two weeks), with lower rates of loss over the following four to five months. Biofouling development followed a succ...
Source: Biofouling - April 14, 2019 Category: Molecular Biology Authors: South PM, Floerl O, Jeffs AG Tags: Biofouling Source Type: research

Towards an absolute scale for adhesion strength of ship hull microfouling.
Abstract In-water ships' hull cleaning enables significant fuel savings through removal of marine fouling from surfaces. However, cleaning may also shorten the lifetime of hull coatings, with a subsequent increase in the colonization and growth rate of fouling organisms. Deleterious effects of cleaning would be minimized by matching cleaning forces to the adhesion strength of the early stages of fouling, or microfouling. Calibrated waterjets are routinely used to compare different coatings in terms of the adhesion strength of microfouling. However, an absolute scale is lacking for translating such results into cle...
Source: Biofouling - April 10, 2019 Category: Molecular Biology Authors: Oliveira DR, Larsson L, Granhag L Tags: Biofouling Source Type: research

Bacillus cereus biofilm formation on central venous catheters of hospitalised cardiac patients.
This study clearly shows that B. cereus persisting in hospital ward environments may constitute a risk factor from repeated contamination of CVCs. PMID: 30950292 [PubMed - as supplied by publisher] (Source: Biofouling)
Source: Biofouling - April 5, 2019 Category: Molecular Biology Authors: Ikram S, Heikal A, Finke S, Hofgaard A, Rehman Y, Sabri AN, Økstad OA Tags: Biofouling Source Type: research