Quorum quenching (QQ)-based strategies are efficient for biofouling control.However,the feasibility of using QQ bacteria in antibiotic-stressed membrane bioreactors (MBRs) remains unknown.In this study,we isolated thr...Quorum quenching (QQ)-based strategies are efficient for biofouling control.However,the feasibility of using QQ bacteria in antibiotic-stressed membrane bioreactors (MBRs) remains unknown.In this study,we isolated three novel QQ strains (Bacillus sp.QX01 and QX03,Delftia sp.QX14) from the activated sludge of an actual MBR.They can degrade 11 N-acylhomoserine lactones (AHLs) with high efficiencies and rates through intracellular QQ pathways involving putative acylases and lactonases.Running two lab-scale MBRs,we found that introducing antibiotics (sulfamethoxazole,azithromycin,and ciprofloxacin,each at100μg/L) shortened the fouling cycle by 71.4%.However,the immobilized inoculation of QX01 into one MBR extended the fouling cycle by 1.5-2.0 times.Quantitative detection revealed that QX01 significantly reduced the concentrations of two AHLs (C4-HSL and C8-HSL),which were positively correlated with the contents of extracellular polymeric substances(EPS)(Pearson’s r=0.62-0.83,P<0.01).This suggests that QX01 could perform its QQ activity robustly under antibiotic stress,thereby inhibiting EPS production (proteins especially) and biofilm formation.Moreover,QX01 notably altered the succession patterns of both sludge and fouling communities,with more pronounced effects on abundant taxa.Genera associated with AHL synthesis and EPS production,such as Terrimonas and Rhodobacter,were significantly depleted,contributing to the mitigated biofouling.Additionally,QX01 increased the bacterial community diversity (evenness especially),which was inhibited by antibiotics.Overall,we demonstrate that the novel QQ bacteria could be effective for biofouling control in antibiotic-stressed MBRs,though future work is needed to develop practical approaches for prolonging QQ activity.展开更多
The assemblages of unicellular microalgae and bacteria in phytoplankton communities can generally result in biodeterioration of metals in marine environment.In this study,the self-promoted biofouling mechanism underne...The assemblages of unicellular microalgae and bacteria in phytoplankton communities can generally result in biodeterioration of metals in marine environment.In this study,the self-promoted biofouling mechanism underneath red-tide alga Phaeodactylum tricornutum and its symbiotic bacterium Bacillus altitudinis was systematically revealed.The mutualistic interaction of the bacteria and algae quadrupled the corrosion rate in comparison to the individual effect of the bacterium or algal strain alone.Reversely,the corroded metal appeared to be an accelerator that can stimulate the activity of the P.tricornutum and aggravate the biological pollution based on the result of 62.3%up-regulation of the key photosynthesis genes.The corrosion-biofouling-accelerated corrosion-deteriorated biofouling formed a vicious cycle.展开更多
High strength-to-weight ratio, commendable biocompatibility and excellent corrosion resistance make Ti alloys widely applicable in aerospace, medical and marine industries. However, these alloys suffer from serious bi...High strength-to-weight ratio, commendable biocompatibility and excellent corrosion resistance make Ti alloys widely applicable in aerospace, medical and marine industries. However, these alloys suffer from serious biofouling, and may become vulnerable to corrosion attack under some extreme marine conditions. The passivating and biofouling performance of Ti alloys can be attributed to their compact, stable and protective films. This paper comprehensively reviews the passivating and biofouling behavior, as well as their mechanisms, for typical Ti alloys in various marine environments. This review aims to help extend applications of Ti alloys in extremely harsh marine conditions.展开更多
This study on the characteristics of fouling communities in offshore areas south of Hainan Island, northern South China Sea, was conducted at four sites there. At each station, test panels on iron frames were hung on ...This study on the characteristics of fouling communities in offshore areas south of Hainan Island, northern South China Sea, was conducted at four sites there. At each station, test panels on iron frames were hung on the mooring system at different depths. Data on biofouling were mainly obtained by examination of the fouled test panels. Organisms attached to buoys and anchors were scraped off and examined also. The results showed that the thickness and biomass of marine growth that increased the fluid loading on offshore installations depended to a large extent on hard foulers, i.e. mollusks and acorn barnacles. Algae, hydroids, stalked barnacles and bryozoans were important fouling species. The occurrence frequency and biomass of acorn barnacles decreased with increasing distance from the shore.展开更多
Golden mussel Limnoperna fortunei(Dunker 1857) is a filter-collector species of fresh water mussel originating from southern China. In the water transfer tunnels from the East River to Shenzhen and Hong Kong, golden m...Golden mussel Limnoperna fortunei(Dunker 1857) is a filter-collector species of fresh water mussel originating from southern China. In the water transfer tunnels from the East River to Shenzhen and Hong Kong, golden mussels attach to the walls of pipelines and gates, causing serious biofouling, increased flow resistance, and resulted in corrosion of the tunnel wall. Golden mussel has very high environmental adaptability and may colonize habitats with low dissolved oxygen and a wide range of trophic levels. The colonization process of the species on solid surface was studied in the Xizhijiang River, a tributary of the East River and the main water resource of Shenzhen from March 2010 to April 2011. The results showed that the golden mussel completed three generations and reproduced six cohorts per year in the tropic zone. Water temperature was the controlling factor for the growth rate and maturity of each cohort. Based on the results, an ecological method for controlling the invasion of golden mussels in water transfer tunnels was proposed.展开更多
A series of orthogonal array experiments were conducted using carbon source, ammonia nitrogen and total phosphorus （TP） as major influencing factors to investigate the effects of nutrients on biofouling formation an...A series of orthogonal array experiments were conducted using carbon source, ammonia nitrogen and total phosphorus （TP） as major influencing factors to investigate the effects of nutrients on biofouling formation and preponderant bacteria diversity in the recirculatiug cooling water system. Carbon source was demonstrated to be the most significant determinant affecting the biofouling formation. A minimum biofouling outcome was obtained when BOD2, NHa＋-N and TP were 25, 10, and 1 mg/L, respectively. Then the preponderant bacteria strains in biofouling mass under two typical culture conditions （negative and favorable） were identified applying both traditional biochemical methods and further molecular biology technology with phylogenetic affiliation analysis, which indicated that Enterobacteriaceae Enterobacter, Micrococcaceae Staphylococcus, Bacillaceae Bacillus, Enterobacteriaceae Proteus, Neisseriaceae Neisseria and Pseudomonadaceae Pseudomonas were dominant under negative condition, while Enterobacteriaceae Klebsiella, Enterobacteriaceae Enterobacter and Microbacterium - under favorable one.展开更多
This paper presents an environm centally friendly method of inhibiting biofouling especially acorn barnacles on surfaces under water by using nicotine and selenium in the form of Se（0）, or such a substance which can...This paper presents an environm centally friendly method of inhibiting biofouling especially acorn barnacles on surfaces under water by using nicotine and selenium in the form of Se（0）, or such a substance which can be converted into them. Both of the substances are necessary to oxygen dependent organisms and will be used after conversion, but are toxic in high doses. By adding the substances to paint or other surface treatment agent which marine surfaces are treated with, organisms which are trying to establish themselves on the surfaces will be exposed to so high doses, the reactions which the settling is based on are disturbed. When the substances leak out into the seas, they will act as environment protectors, as they promote the development of organisms. Nicotine is transformed to nicotine amid which is the reactive part in NADH and one of the most important substances for the transference of hydrogen. Selenite is reduced to Se（0）, also involved in the transport chain of hydrogen to reducible oxygen. However, large quantities Se（0） may disturb the reactions of sulphur b＇./binding to it and impairing the formation of S-S-bridges.展开更多
In this research,an Underwater Biofouling Panel(UWBFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of Mannar.Forty-four biofoulers were identified from four...In this research,an Underwater Biofouling Panel(UWBFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of Mannar.Forty-four biofoulers were identified from four types of selected test panels.Among these biofoulers,Amphibalanus amphitrite(Darwin,1854)was the dominant one.The concrete panel encouraged the highest barnacle density compared to the other panels.Three series of test panels were used to assess the seasonal density of biofouling communities.The overall variation in barnacle count in the seaward and shoreward sides of all these three series were tested.They were found to be significantly different from each other.The greater variations in the barnacle density observed in this study in A-series of test panels could be due to the lack of or absence of other foulers to compete within the fortnight.The Shannon-Wiener species diversity index showed the highest diversity in wood substratum among the three series with greater accumulation of different types of fouling organisms.Multivariate analyses were also performed to understand the seasonal variation as well as the settlement pattern on the different directions of test panels based on validated data.PCA showed a strong variability(PC1 between 70.8%and 98.6%variance)between the directions of the panels in connection with barnacle density.The shade plot and CAP analysis segregated the short-term A-series test panels from the long-term(B-and C-series)test panels.Hence,the output was helpful in understanding the recruitment status of various faunal resources involved in the biofouling processes.展开更多
From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang River Estuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Tota...From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang River Estuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Totally, 340 species (see Appendix I) have been recorded and identified, six of which are new. At the same time, research on the biology of the cirripede, bryozoan, polychaete and mollusc communities were also conducted. Twenty-three related papers have been published. This review summarizes works in Hong Kong over past twenty years, and some unpublished data are also reported.展开更多
The biofouling of RO （Reverse Osmosis） system is one of the most common problems in highly contaminated demineralization and wastewater reuse system. The biological fouling occurs due to the bacteria growth and prol...The biofouling of RO （Reverse Osmosis） system is one of the most common problems in highly contaminated demineralization and wastewater reuse system. The biological fouling occurs due to the bacteria growth and proliferation under nutritive environment, resulting in a dramatic increase of dP （differential pressure） in the RO system, which requires frequent system shutdown for cleaning. This paper discusses the effectiveness of low-dP RO element and periodic flushing on the biofouling scheme of industrial steel mill wastewater reuse system. The low-dP RO element is able to provide low RO system dP, which is expressed to be lower biofouling starting point during the industrial system operation. However, the periodic flushing utilizes fresh water to remove the biofilm deposit along with feed channel. The long term operation performance demonstrated strong caustic is effective in removing the biofilm and recovering RO system performance. It is experimentally validated that, in the case of a high biofouling environment, low-dP RO element and periodic flushing is able to extend the cleaning cycles by 36.6% and 11.4%, respectively. Meanwhile, a joint application of both methods is proven to improve the biofouling control and extend the cleaning cycle by 62.5%, as compared to standard RO technology.展开更多
The authors investigated the leaching rate of antifouling agents from marine paint using an instrument that allows direct measurement from the flat bottom of ship hulls shortly after dry dock. A similar procedure was ...The authors investigated the leaching rate of antifouling agents from marine paint using an instrument that allows direct measurement from the flat bottom of ship hulls shortly after dry dock. A similar procedure was also used for painted flat panels that were immersed in the ocean. The relationship between leaching rate and fouling condition was considered by quantifying the amount of ATP （adenosine triphosphate） on the surface of immersed flat panel using fluorescence spectroscopy. The leaching rate results from ship hulls showed good agreement with the value by reporting of leaching rate of antifouling agents. The fluorescence spectroscopy results showed that the amount of ATP on the surface of the panel increased over time as the leaching rate fell, which implies an inverse relationship between leaching rate and fouling index. Fluorescence spectroscopy was also seen to be a simple method for evaluating the relationship between biofouling indexes and leaching rate.展开更多
The IMO(International Maritime Organization)recognized the problem of invasive species invasion and adopted the“International Convention for the Control and Management of Ships’Ballast Water and Sediments”in 2004,w...The IMO(International Maritime Organization)recognized the problem of invasive species invasion and adopted the“International Convention for the Control and Management of Ships’Ballast Water and Sediments”in 2004,which came into force on September 8,2017.In 2011,the IMO approved the“Guidelines for the Control and Management of Ships’Biofouling to Minimize the Transfer of Invasive Aquatic Species”to minimize the movement of invasive species by hull-attached organisms and required ships to manage the organisms attached to their hulls.Invasive species enter new environments through ships’ballast water and hull attachment.However,several obstacles to implementing these guidelines have been identified,including a lack of underwater cleaning equipment,regulations on underwater cleaning activities in ports,and difficulty in accessing crevices in underwater areas.The shipping industry,which is the party responsible for understanding these guidelines,wants to implement them for fuel cost savings resulting from the removal of organisms attached to the hull,but they anticipate significant difficulties in implementing the guidelines due to the obstacles mentioned above.Robots or people remove the organisms attached to the hull underwater,and the resulting wastewater includes various species of organisms and particles of paint and other pollutants.Currently,there is no technology available to sterilize the organisms in the wastewater or stabilize the heavy metals in the paint particles.In this study,we aim to analyse the characteristics of the wastewater generated from the removal of hull-attached organisms and select the optimal treatment technology.The organisms in the wastewater generated from the removal of the attached organisms meet the biological treatment standard(D-2)using the sterilization technology applied in the ships’ballast water treatment system.The heavy metals and other pollutants in the paint particles generated during removal are treated using stabilization technologies such as thermal decomposition.The wastewater generated is treated using a two-step process:(1)development of sterilization technology through pretreatment filtration equipment and electrolytic sterilization treatment and(2)development of technology for removing particle pollutants such as heavy metals and dissolved inorganic substances.Through this study,we will develop a biological removal technology and an environmentally friendly processing system for the waste generated after removal that meets the requirements of the government and the shipping industry and lay the groundwork for future treatment standards.展开更多
The study investigates the potential of the serpulid tubeworm Ficopomatus sp.,sourced from Jesolo Lido(Venice,Italy),for CCS(Carbon Capture and Storage).Specimens were processed to extract bioactive compounds using a ...The study investigates the potential of the serpulid tubeworm Ficopomatus sp.,sourced from Jesolo Lido(Venice,Italy),for CCS(Carbon Capture and Storage).Specimens were processed to extract bioactive compounds using a 50%polypropylene glycol-water solvent system.Extracts were analysed and purified using column gel filtration chromatography,with fractions identified by TLC(Thin Layer Chromatography)and further characterized for antioxidant and antibacterial activities.Antioxidant activity was detected via DPPH(2,2-Diphenyl-1-Picrylhydrazyl)spraying on TLC plates,while antibacterial activity was evaluated using the antibiogram paper disk diffusion method.Enzyme activity in the fractions was previously confirmed through a bromothymol blue test followed by spectrophotometric analysis.The primary goal was to explore the CCS potential,using an experimental module involving Arduino Uno embedded microprocessor for the CO_(2) measurement and to confirm the conversion into insoluble carbonates(storage).The most active fraction,identified as S1,showed significant CCS action,confirmed by microscopic observation of calcareous deposits on treated sponges.These findings suggest that Ficopomatus sp.can be used in CCS research highlighting its potential for biotechnological applications in mitigating climate change.The paper underscores the importance of marine organisms in CCS and offers insights into innovative strategies for environmental conservation and carbon management.展开更多
Marine biofouling causes severe economical and environmental challenges to marine industries and maritime activities.Biofouling prevention has emerged as one of the most pressing issues in water-related industries.Rec...Marine biofouling causes severe economical and environmental challenges to marine industries and maritime activities.Biofouling prevention has emerged as one of the most pressing issues in water-related industries.Recently,the slippery liquid-infused porous surfaces(SLIPSs)have shown great potential for biofouling prevention across a broad spectrum of fouling organisms.However,our understanding of the mechanisms by which SLIPSs prevent biofouling remains limited.In this study,we discovered that oil-infused polydimethylsiloxane elastomer(i-PDMS),a silicone-based SLIPS variant,significantly inhibited the sensory responses of the fouling mussel Mytilopsis sallei,particularly at its sensory organ,the foot.Using bioinformatics and molecular biology analyses,we demonstrated that i-PDMS disrupts larval settlement of M.sallei by interfering with the mechanosensitive transient receptor potential melastatin-subfamily member 7(TRPM7)channel,which is highly expressed in the foot during the settlement process.Furthermore,adhesion assays and molecular dynamics simulations revealed that the secreted foot proteins of the mussel are unable to effectively interact with the i-PDMS surface due to nanoscale fluctuations at the material interface.These findings enhance our understanding of how fouling organisms sense and adhere to surfaces and provide deeper insights into the antifouling mechanisms of SLIPS.展开更多
Thrombosis and infection are 2 major complications associated with central venous catheters(CVCs),resulting in substantial mortality and morbidity.The concurrent long-term administration of antibiotics and anticoagula...Thrombosis and infection are 2 major complications associated with central venous catheters(CVCs),resulting in substantial mortality and morbidity.The concurrent long-term administration of antibiotics and anticoagulants to address these complications have been demonstrated to cause severe side effects such as antibiotic resistance and bleeding.To mitigate these complications with minimal or no drug utilization,we developed a bioinspired zwitterionic block polymer-armored nitric oxide(NO)-generating functional coating for surface modification of CVCs.This armor was fabricated by precoating with a Cu-dopamine(DA)/selenocysteamine(SeCA)(Cu-DA/SeCA)network film capable of catalytically generating NO on the CVCs surface,followed by grafting of a zwitterionic p(DMA-b-MPC-b-DMA)polymer brush.The synergistic effects of active attack by NO and copper ions provided by Cu-DA/SeCA network and passive defense by zwitterionic polymer brush imparted the CVCs surface with durable antimicrobial properties and marked inhibition of platelets and fibrinogen.The in vivo studies confirmed that the surface-armored CVCs could effectively reduce inflammation and inhibit thrombosis,indicating a promising potential for clinical applications.展开更多
Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and n...Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and nano-copper oxide(CuO),reported to have biofouling resistance.Leaching of nano CuO from the net to the aquatic environment and its bioaccumulation in fish is the major concern against the technology adoption.The present study aimed to understand the accumulation of copper in fishes grown in a nano CuO treated aquaculture cage net.Studied the leaching pattern of nano CuO,biofouling inhibition and changes in strength of the cage net due to the nano CuO treatments.Fishes grown in the treated cages exhibited normal growth characteristics with no signs of abnormalities and also copper in their organs were within the prescribed standard limit.The CuO treated cage net exhibited excellent biofouling resistance and the percentage of occlusion of mesh by foulers were 56.77%more efficient than untreated cage net.Rate of nano CuO leached to the aquatic system was less than 8μg/g⋅d.The fouling organism assemblage on untreated and treated net was 18 and 11 species,respectively.Major calcareous shelled foulers were absent on treated nets.The study highlighted the potential application of nano CuO treatment to control biofouling in aquaculture cages.展开更多
Transparent exopolymer particles(TEPs)are a class of transparent gel-like polysaccharides,which have been widely detected in almost every kind of feed water to membrane systems,including freshwater,seawater and wastew...Transparent exopolymer particles(TEPs)are a class of transparent gel-like polysaccharides,which have been widely detected in almost every kind of feed water to membrane systems,including freshwater,seawater and wastewater.Although TEP have been thought to be related to the membrane fouling,little information is currently available for their influential mechanisms and the pertinence to biofouling development.The present study,thus,aims to explore the impact of TEPs on biofouling development during ultrafiltration.TEP samples were inoculated with bacteria for several hours before filtration and the formation of“protobiofilm”(pre-colonized TEP by bacteria)was examined and its influence on biofouling was determined.It was observed that the bacteria can easily and quickly attach onto TEPs and form protobiofilms.Ultrafiltration experiments further revealed that TEP-protobiofilms served as carriers which facilitated and accelerated transport of bacteria to membrane surface,leading to rapid development of biofouling on the ultrafiltration membrane surfaces.Moreover,compared to the feed water containing independent bacteria and TEPs,more flux decline was observed with TEP-protobiofilms.Consequently,it appeared from this study that TEP-protobiofilms play a vital role in the development of membrane biofouling,but unfortunately,this phenomenon has been often overlooked in the literature.Obviously,these findings in turn may also challenge the current understanding of organic fouling and biofouling as membrane fouling caused by TEP-protobiofilm is a combination of both.It is expected that this study might promote further research in general membrane fouling mechanisms and the development of an effective mitigation strategy.展开更多
Microbial fuel cells(MFCs)incorporating air-breathing cathodes have emerged as a promising ecofriendly wastewater treatment technology capable of operating on an energy-free basis.However,the inevitable biofouling of ...Microbial fuel cells(MFCs)incorporating air-breathing cathodes have emerged as a promising ecofriendly wastewater treatment technology capable of operating on an energy-free basis.However,the inevitable biofouling of these devices rapidly decreases cathodic catalytic activity and also reduces the stability of MFCs during long-term operation.The present work developed a novel microbial separator for use in air-breathing MFCs that protects cathodic catalytic activity.In these modified devices,microbes preferentially grow on the microbial separator rather than the cathodic surface such that biofouling is prevented.Trials showed that this concept provided low charge transfer and mass diffusion resistance values during the cathodic oxygen reduction reaction of 4.6±1.3 and 17.3±6.8 U,respectively,after prolonged operation.The maximum power density was found to be stable at 1.06±0.07 W m2 throughout a long-term test and the chemical oxygen demand removal efficiency was increased to 92%compared with a value of 83%for MFCs exhibiting serious biofouling.In addition,a cathode combined with a microbial separator demonstrated less cross-cathode diffusion of oxygen to the anolyte.This effect indirectly induced the growth of electroactive bacteria and produced higher currents in air-breathing MFCs.Most importantly,the present microbial separator concept enhances both the lifespan and economics of air-breathing MFCs by removing the need to replace or regenerate the cathode during longterm operation.These results indicate that the installation of a microbial separator is an effective means of stabilizing power generation and ensuring the cost-effective performance of air-breathing MFCs intended for future industrial applications.展开更多
Evaluating species composition and dynamic shifts within fouling communities is essential for developing effective strate-gies to manage biofouling in marine fish aquaculture.The coastal area in the Yellow Sea is a ke...Evaluating species composition and dynamic shifts within fouling communities is essential for developing effective strate-gies to manage biofouling in marine fish aquaculture.The coastal area in the Yellow Sea is a key area for cage aquaculture in China;however,this region faces significant challenges from biofouling organisms.Here,we employed an experimental approach in a filed mesocosm in a net cage aquaculture area in the Yellow Sea,with weekly monitoring of changes in macrofouling species on mesh nets and in the seawater,to assess the utility of water eDNA metabarcoding for identifying macrofoulers.We compared the temporal variation patterns in the composition and diversity of macrofouling communities identified through morphological method as well as COI and 18S rRNA metabarcoding.The results showed that metabarcoding detected the majority of macrofoulers identified through morphological method(64%),and revealed additional species that were overlooked by traditional monitoring approach.Furthermore,the changes in diversity and community composition over sampling dates in COI data were generally consistent with those in morphological identification,although a temporal lag existed between these two approaches.A notable shift in the fouling community occurred at the end of June with the appearance of Ectopleura crocea and Caprella sp.,marking a pivotal change in its structure.Future research could focus on developing targeted primers for these key fouling species,which would enhance the efficiency of monitoring efforts.展开更多
Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of th...Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of the TCA cycle,emerges as a promising candidate for regulating energy metabolism.However,sus-tainable methods in providing energy metabolic substrates across the whole regenerating process has been neglected.Herein,a metabotissugenic membrane con-sisting of poly(octamethylene citrate)and L-lysine diisocyanate,POCL_(10),was developed to consistently biodegrade and provide citrate substrates.Furthermore,the POCL_(10) membrane exhibited self-sealing properties due to the introduction of strong hydrogen bonds and demonstrated anti-biofouling capacity in vitro.Intrigu-ingly,POCL_(10) showed excellent regenerative capability by promptly upregulating TSPC proliferation,energy metabolism and differentiation.In vivo,POCL_(10) was effortlessly wrapped around the injured Achilles tendon showcasing with anti-tissue adhesion and prominent collagen organization along with strengthened biomechanical properties.Hence,the development of POCL expands the reservoir of available biodegradable citrate-based biomaterials and provides a unique metabotissugenic biomaterial platform for tendon anti-biofouling and repair.展开更多
基金supported by the National Natural Science Foundation of China (Nos.51938001 and 52300073)。
文摘Quorum quenching (QQ)-based strategies are efficient for biofouling control.However,the feasibility of using QQ bacteria in antibiotic-stressed membrane bioreactors (MBRs) remains unknown.In this study,we isolated three novel QQ strains (Bacillus sp.QX01 and QX03,Delftia sp.QX14) from the activated sludge of an actual MBR.They can degrade 11 N-acylhomoserine lactones (AHLs) with high efficiencies and rates through intracellular QQ pathways involving putative acylases and lactonases.Running two lab-scale MBRs,we found that introducing antibiotics (sulfamethoxazole,azithromycin,and ciprofloxacin,each at100μg/L) shortened the fouling cycle by 71.4%.However,the immobilized inoculation of QX01 into one MBR extended the fouling cycle by 1.5-2.0 times.Quantitative detection revealed that QX01 significantly reduced the concentrations of two AHLs (C4-HSL and C8-HSL),which were positively correlated with the contents of extracellular polymeric substances(EPS)(Pearson’s r=0.62-0.83,P<0.01).This suggests that QX01 could perform its QQ activity robustly under antibiotic stress,thereby inhibiting EPS production (proteins especially) and biofilm formation.Moreover,QX01 notably altered the succession patterns of both sludge and fouling communities,with more pronounced effects on abundant taxa.Genera associated with AHL synthesis and EPS production,such as Terrimonas and Rhodobacter,were significantly depleted,contributing to the mitigated biofouling.Additionally,QX01 increased the bacterial community diversity (evenness especially),which was inhibited by antibiotics.Overall,we demonstrate that the novel QQ bacteria could be effective for biofouling control in antibiotic-stressed MBRs,though future work is needed to develop practical approaches for prolonging QQ activity.
基金The support of the National Key Research and Development Program of China(No.2017YFB0702100)the National Natural Science Foundation of China(key project No.51731008,general project Nos.51671163,51901198)。
文摘The assemblages of unicellular microalgae and bacteria in phytoplankton communities can generally result in biodeterioration of metals in marine environment.In this study,the self-promoted biofouling mechanism underneath red-tide alga Phaeodactylum tricornutum and its symbiotic bacterium Bacillus altitudinis was systematically revealed.The mutualistic interaction of the bacteria and algae quadrupled the corrosion rate in comparison to the individual effect of the bacterium or algal strain alone.Reversely,the corroded metal appeared to be an accelerator that can stimulate the activity of the P.tricornutum and aggravate the biological pollution based on the result of 62.3%up-regulation of the key photosynthesis genes.The corrosion-biofouling-accelerated corrosion-deteriorated biofouling formed a vicious cycle.
文摘High strength-to-weight ratio, commendable biocompatibility and excellent corrosion resistance make Ti alloys widely applicable in aerospace, medical and marine industries. However, these alloys suffer from serious biofouling, and may become vulnerable to corrosion attack under some extreme marine conditions. The passivating and biofouling performance of Ti alloys can be attributed to their compact, stable and protective films. This paper comprehensively reviews the passivating and biofouling behavior, as well as their mechanisms, for typical Ti alloys in various marine environments. This review aims to help extend applications of Ti alloys in extremely harsh marine conditions.
文摘This study on the characteristics of fouling communities in offshore areas south of Hainan Island, northern South China Sea, was conducted at four sites there. At each station, test panels on iron frames were hung on the mooring system at different depths. Data on biofouling were mainly obtained by examination of the fouled test panels. Organisms attached to buoys and anchors were scraped off and examined also. The results showed that the thickness and biomass of marine growth that increased the fluid loading on offshore installations depended to a large extent on hard foulers, i.e. mollusks and acorn barnacles. Algae, hydroids, stalked barnacles and bryozoans were important fouling species. The occurrence frequency and biomass of acorn barnacles decreased with increasing distance from the shore.
文摘Golden mussel Limnoperna fortunei(Dunker 1857) is a filter-collector species of fresh water mussel originating from southern China. In the water transfer tunnels from the East River to Shenzhen and Hong Kong, golden mussels attach to the walls of pipelines and gates, causing serious biofouling, increased flow resistance, and resulted in corrosion of the tunnel wall. Golden mussel has very high environmental adaptability and may colonize habitats with low dissolved oxygen and a wide range of trophic levels. The colonization process of the species on solid surface was studied in the Xizhijiang River, a tributary of the East River and the main water resource of Shenzhen from March 2010 to April 2011. The results showed that the golden mussel completed three generations and reproduced six cohorts per year in the tropic zone. Water temperature was the controlling factor for the growth rate and maturity of each cohort. Based on the results, an ecological method for controlling the invasion of golden mussels in water transfer tunnels was proposed.
基金supported by the National Natural Science Foundation of China (No.20707040)the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No. PCRRF08002).
文摘A series of orthogonal array experiments were conducted using carbon source, ammonia nitrogen and total phosphorus （TP） as major influencing factors to investigate the effects of nutrients on biofouling formation and preponderant bacteria diversity in the recirculatiug cooling water system. Carbon source was demonstrated to be the most significant determinant affecting the biofouling formation. A minimum biofouling outcome was obtained when BOD2, NHa＋-N and TP were 25, 10, and 1 mg/L, respectively. Then the preponderant bacteria strains in biofouling mass under two typical culture conditions （negative and favorable） were identified applying both traditional biochemical methods and further molecular biology technology with phylogenetic affiliation analysis, which indicated that Enterobacteriaceae Enterobacter, Micrococcaceae Staphylococcus, Bacillaceae Bacillus, Enterobacteriaceae Proteus, Neisseriaceae Neisseria and Pseudomonadaceae Pseudomonas were dominant under negative condition, while Enterobacteriaceae Klebsiella, Enterobacteriaceae Enterobacter and Microbacterium - under favorable one.
文摘This paper presents an environm centally friendly method of inhibiting biofouling especially acorn barnacles on surfaces under water by using nicotine and selenium in the form of Se（0）, or such a substance which can be converted into them. Both of the substances are necessary to oxygen dependent organisms and will be used after conversion, but are toxic in high doses. By adding the substances to paint or other surface treatment agent which marine surfaces are treated with, organisms which are trying to establish themselves on the surfaces will be exposed to so high doses, the reactions which the settling is based on are disturbed. When the substances leak out into the seas, they will act as environment protectors, as they promote the development of organisms. Nicotine is transformed to nicotine amid which is the reactive part in NADH and one of the most important substances for the transference of hydrogen. Selenite is reduced to Se（0）, also involved in the transport chain of hydrogen to reducible oxygen. However, large quantities Se（0） may disturb the reactions of sulphur b＇./binding to it and impairing the formation of S-S-bridges.
基金supported by the government of India through DOD-OSTC program entitled‘Biofouling and Antifouling Organisms in the Gulf of Mannar,Southeast Coast of India’(No.DOD/11-MRDF/4/11/UNI/97/P-15)funding by the Department of Ocean Development(Ministry of Earth Sciences,Government of India)through project(No.DOD/11-MRDF/4/11/UNI/97/P-15)。
文摘In this research,an Underwater Biofouling Panel(UWBFP)system was erected for the qualitative and quantitative estimation of macro fouling organisms in the Gulf of Mannar.Forty-four biofoulers were identified from four types of selected test panels.Among these biofoulers,Amphibalanus amphitrite(Darwin,1854)was the dominant one.The concrete panel encouraged the highest barnacle density compared to the other panels.Three series of test panels were used to assess the seasonal density of biofouling communities.The overall variation in barnacle count in the seaward and shoreward sides of all these three series were tested.They were found to be significantly different from each other.The greater variations in the barnacle density observed in this study in A-series of test panels could be due to the lack of or absence of other foulers to compete within the fortnight.The Shannon-Wiener species diversity index showed the highest diversity in wood substratum among the three series with greater accumulation of different types of fouling organisms.Multivariate analyses were also performed to understand the seasonal variation as well as the settlement pattern on the different directions of test panels based on validated data.PCA showed a strong variability(PC1 between 70.8%and 98.6%variance)between the directions of the panels in connection with barnacle density.The shade plot and CAP analysis segregated the short-term A-series test panels from the long-term(B-and C-series)test panels.Hence,the output was helpful in understanding the recruitment status of various faunal resources involved in the biofouling processes.
文摘From 1980 to 1998, biofouling communities in Hong Kong waters, the Zhujiang River Estuary and the Mirs Bay were studied and a total of 610 samples. The samples were collected from vessels, buoys, piers and cages. Totally, 340 species (see Appendix I) have been recorded and identified, six of which are new. At the same time, research on the biology of the cirripede, bryozoan, polychaete and mollusc communities were also conducted. Twenty-three related papers have been published. This review summarizes works in Hong Kong over past twenty years, and some unpublished data are also reported.
文摘The biofouling of RO （Reverse Osmosis） system is one of the most common problems in highly contaminated demineralization and wastewater reuse system. The biological fouling occurs due to the bacteria growth and proliferation under nutritive environment, resulting in a dramatic increase of dP （differential pressure） in the RO system, which requires frequent system shutdown for cleaning. This paper discusses the effectiveness of low-dP RO element and periodic flushing on the biofouling scheme of industrial steel mill wastewater reuse system. The low-dP RO element is able to provide low RO system dP, which is expressed to be lower biofouling starting point during the industrial system operation. However, the periodic flushing utilizes fresh water to remove the biofilm deposit along with feed channel. The long term operation performance demonstrated strong caustic is effective in removing the biofilm and recovering RO system performance. It is experimentally validated that, in the case of a high biofouling environment, low-dP RO element and periodic flushing is able to extend the cleaning cycles by 36.6% and 11.4%, respectively. Meanwhile, a joint application of both methods is proven to improve the biofouling control and extend the cleaning cycle by 62.5%, as compared to standard RO technology.
文摘The authors investigated the leaching rate of antifouling agents from marine paint using an instrument that allows direct measurement from the flat bottom of ship hulls shortly after dry dock. A similar procedure was also used for painted flat panels that were immersed in the ocean. The relationship between leaching rate and fouling condition was considered by quantifying the amount of ATP （adenosine triphosphate） on the surface of immersed flat panel using fluorescence spectroscopy. The leaching rate results from ship hulls showed good agreement with the value by reporting of leaching rate of antifouling agents. The fluorescence spectroscopy results showed that the amount of ATP on the surface of the panel increased over time as the leaching rate fell, which implies an inverse relationship between leaching rate and fouling index. Fluorescence spectroscopy was also seen to be a simple method for evaluating the relationship between biofouling indexes and leaching rate.
基金supported by IITP(Institute of Information&Communications Technology Planning&Evaluation)grant funded by the Korea government(MSIT)(RS-2023-0022378,Development of industry-level technology bridging ICT for coal2biomethane)and KIMST(Korea Institute of Marine Science&Technology Promotion)funded by the Ministry of Oceans and Fisheries,Korea(No.20210500,Development of treatment technology of marine bio-fouling on ship hull).
文摘The IMO(International Maritime Organization)recognized the problem of invasive species invasion and adopted the“International Convention for the Control and Management of Ships’Ballast Water and Sediments”in 2004,which came into force on September 8,2017.In 2011,the IMO approved the“Guidelines for the Control and Management of Ships’Biofouling to Minimize the Transfer of Invasive Aquatic Species”to minimize the movement of invasive species by hull-attached organisms and required ships to manage the organisms attached to their hulls.Invasive species enter new environments through ships’ballast water and hull attachment.However,several obstacles to implementing these guidelines have been identified,including a lack of underwater cleaning equipment,regulations on underwater cleaning activities in ports,and difficulty in accessing crevices in underwater areas.The shipping industry,which is the party responsible for understanding these guidelines,wants to implement them for fuel cost savings resulting from the removal of organisms attached to the hull,but they anticipate significant difficulties in implementing the guidelines due to the obstacles mentioned above.Robots or people remove the organisms attached to the hull underwater,and the resulting wastewater includes various species of organisms and particles of paint and other pollutants.Currently,there is no technology available to sterilize the organisms in the wastewater or stabilize the heavy metals in the paint particles.In this study,we aim to analyse the characteristics of the wastewater generated from the removal of hull-attached organisms and select the optimal treatment technology.The organisms in the wastewater generated from the removal of the attached organisms meet the biological treatment standard(D-2)using the sterilization technology applied in the ships’ballast water treatment system.The heavy metals and other pollutants in the paint particles generated during removal are treated using stabilization technologies such as thermal decomposition.The wastewater generated is treated using a two-step process:(1)development of sterilization technology through pretreatment filtration equipment and electrolytic sterilization treatment and(2)development of technology for removing particle pollutants such as heavy metals and dissolved inorganic substances.Through this study,we will develop a biological removal technology and an environmentally friendly processing system for the waste generated after removal that meets the requirements of the government and the shipping industry and lay the groundwork for future treatment standards.
文摘The study investigates the potential of the serpulid tubeworm Ficopomatus sp.,sourced from Jesolo Lido(Venice,Italy),for CCS(Carbon Capture and Storage).Specimens were processed to extract bioactive compounds using a 50%polypropylene glycol-water solvent system.Extracts were analysed and purified using column gel filtration chromatography,with fractions identified by TLC(Thin Layer Chromatography)and further characterized for antioxidant and antibacterial activities.Antioxidant activity was detected via DPPH(2,2-Diphenyl-1-Picrylhydrazyl)spraying on TLC plates,while antibacterial activity was evaluated using the antibiogram paper disk diffusion method.Enzyme activity in the fractions was previously confirmed through a bromothymol blue test followed by spectrophotometric analysis.The primary goal was to explore the CCS potential,using an experimental module involving Arduino Uno embedded microprocessor for the CO_(2) measurement and to confirm the conversion into insoluble carbonates(storage).The most active fraction,identified as S1,showed significant CCS action,confirmed by microscopic observation of calcareous deposits on treated sponges.These findings suggest that Ficopomatus sp.can be used in CCS research highlighting its potential for biotechnological applications in mitigating climate change.The paper underscores the importance of marine organisms in CCS and offers insights into innovative strategies for environmental conservation and carbon management.
基金supported by the National Natural Science Foundation of China(grant numbers 42106103,U22A20112,and 42306223)the Project of the High-quality Development of Marine and Fishery Industry of Fujian(grant number FJHYF-L-2023-14)the Shandong Provincial Natural Science Foundation(grant number ZR2022QD006).
文摘Marine biofouling causes severe economical and environmental challenges to marine industries and maritime activities.Biofouling prevention has emerged as one of the most pressing issues in water-related industries.Recently,the slippery liquid-infused porous surfaces(SLIPSs)have shown great potential for biofouling prevention across a broad spectrum of fouling organisms.However,our understanding of the mechanisms by which SLIPSs prevent biofouling remains limited.In this study,we discovered that oil-infused polydimethylsiloxane elastomer(i-PDMS),a silicone-based SLIPS variant,significantly inhibited the sensory responses of the fouling mussel Mytilopsis sallei,particularly at its sensory organ,the foot.Using bioinformatics and molecular biology analyses,we demonstrated that i-PDMS disrupts larval settlement of M.sallei by interfering with the mechanosensitive transient receptor potential melastatin-subfamily member 7(TRPM7)channel,which is highly expressed in the foot during the settlement process.Furthermore,adhesion assays and molecular dynamics simulations revealed that the secreted foot proteins of the mussel are unable to effectively interact with the i-PDMS surface due to nanoscale fluctuations at the material interface.These findings enhance our understanding of how fouling organisms sense and adhere to surfaces and provide deeper insights into the antifouling mechanisms of SLIPS.
基金supported by the National Natural Science Foundation of China(82072072,32261160372,52275199,32171326,and 32371377)Guang Dong Basic and Applied Basic Research Foundation(2022B1515130010 and 2021A1515111035)+4 种基金Wenzhou Science and Technology Major Project(Y2023138)Wenzhou Institute,University of Chinese Academy of Sciences startup fund(WIUCASQD2023013)Beijing-Tianjin-Hebei Fundamental Research Cooperation Project(J230001)Leading Talent Project of Guangzhou Development District(2020-L013)Dongguan Science and Technology of Social Development Program(20231800906311).
文摘Thrombosis and infection are 2 major complications associated with central venous catheters(CVCs),resulting in substantial mortality and morbidity.The concurrent long-term administration of antibiotics and anticoagulants to address these complications have been demonstrated to cause severe side effects such as antibiotic resistance and bleeding.To mitigate these complications with minimal or no drug utilization,we developed a bioinspired zwitterionic block polymer-armored nitric oxide(NO)-generating functional coating for surface modification of CVCs.This armor was fabricated by precoating with a Cu-dopamine(DA)/selenocysteamine(SeCA)(Cu-DA/SeCA)network film capable of catalytically generating NO on the CVCs surface,followed by grafting of a zwitterionic p(DMA-b-MPC-b-DMA)polymer brush.The synergistic effects of active attack by NO and copper ions provided by Cu-DA/SeCA network and passive defense by zwitterionic polymer brush imparted the CVCs surface with durable antimicrobial properties and marked inhibition of platelets and fibrinogen.The in vivo studies confirmed that the surface-armored CVCs could effectively reduce inflammation and inhibit thrombosis,indicating a promising potential for clinical applications.
文摘Biofouling is a major issue in aquaculture cages and nano materials based antifouling strategies became more prominent in recent years.Polyethylene aquaculture cage net surface which is modified with polyaniline and nano-copper oxide(CuO),reported to have biofouling resistance.Leaching of nano CuO from the net to the aquatic environment and its bioaccumulation in fish is the major concern against the technology adoption.The present study aimed to understand the accumulation of copper in fishes grown in a nano CuO treated aquaculture cage net.Studied the leaching pattern of nano CuO,biofouling inhibition and changes in strength of the cage net due to the nano CuO treatments.Fishes grown in the treated cages exhibited normal growth characteristics with no signs of abnormalities and also copper in their organs were within the prescribed standard limit.The CuO treated cage net exhibited excellent biofouling resistance and the percentage of occlusion of mesh by foulers were 56.77%more efficient than untreated cage net.Rate of nano CuO leached to the aquatic system was less than 8μg/g⋅d.The fouling organism assemblage on untreated and treated net was 18 and 11 species,respectively.Major calcareous shelled foulers were absent on treated nets.The study highlighted the potential application of nano CuO treatment to control biofouling in aquaculture cages.
基金This work was financially supported by the National Natural Science Foundation of China(Grant Nos.51808019 and 51708338).
文摘Transparent exopolymer particles(TEPs)are a class of transparent gel-like polysaccharides,which have been widely detected in almost every kind of feed water to membrane systems,including freshwater,seawater and wastewater.Although TEP have been thought to be related to the membrane fouling,little information is currently available for their influential mechanisms and the pertinence to biofouling development.The present study,thus,aims to explore the impact of TEPs on biofouling development during ultrafiltration.TEP samples were inoculated with bacteria for several hours before filtration and the formation of“protobiofilm”(pre-colonized TEP by bacteria)was examined and its influence on biofouling was determined.It was observed that the bacteria can easily and quickly attach onto TEPs and form protobiofilms.Ultrafiltration experiments further revealed that TEP-protobiofilms served as carriers which facilitated and accelerated transport of bacteria to membrane surface,leading to rapid development of biofouling on the ultrafiltration membrane surfaces.Moreover,compared to the feed water containing independent bacteria and TEPs,more flux decline was observed with TEP-protobiofilms.Consequently,it appeared from this study that TEP-protobiofilms play a vital role in the development of membrane biofouling,but unfortunately,this phenomenon has been often overlooked in the literature.Obviously,these findings in turn may also challenge the current understanding of organic fouling and biofouling as membrane fouling caused by TEP-protobiofilm is a combination of both.It is expected that this study might promote further research in general membrane fouling mechanisms and the development of an effective mitigation strategy.
基金supported by the National Nature Science Foundation of China(Grant No.52100021)the China Postdoctoral Science Foundation(Grants No.2022M720004 and No.2022M710208)。
文摘Microbial fuel cells(MFCs)incorporating air-breathing cathodes have emerged as a promising ecofriendly wastewater treatment technology capable of operating on an energy-free basis.However,the inevitable biofouling of these devices rapidly decreases cathodic catalytic activity and also reduces the stability of MFCs during long-term operation.The present work developed a novel microbial separator for use in air-breathing MFCs that protects cathodic catalytic activity.In these modified devices,microbes preferentially grow on the microbial separator rather than the cathodic surface such that biofouling is prevented.Trials showed that this concept provided low charge transfer and mass diffusion resistance values during the cathodic oxygen reduction reaction of 4.6±1.3 and 17.3±6.8 U,respectively,after prolonged operation.The maximum power density was found to be stable at 1.06±0.07 W m2 throughout a long-term test and the chemical oxygen demand removal efficiency was increased to 92%compared with a value of 83%for MFCs exhibiting serious biofouling.In addition,a cathode combined with a microbial separator demonstrated less cross-cathode diffusion of oxygen to the anolyte.This effect indirectly induced the growth of electroactive bacteria and produced higher currents in air-breathing MFCs.Most importantly,the present microbial separator concept enhances both the lifespan and economics of air-breathing MFCs by removing the need to replace or regenerate the cathode during longterm operation.These results indicate that the installation of a microbial separator is an effective means of stabilizing power generation and ensuring the cost-effective performance of air-breathing MFCs intended for future industrial applications.
基金supported by grants from the National Key Research and Development Program of China(No.2023YFD2401103)the Fundamental Research Funds for the Central Universities.
文摘Evaluating species composition and dynamic shifts within fouling communities is essential for developing effective strate-gies to manage biofouling in marine fish aquaculture.The coastal area in the Yellow Sea is a key area for cage aquaculture in China;however,this region faces significant challenges from biofouling organisms.Here,we employed an experimental approach in a filed mesocosm in a net cage aquaculture area in the Yellow Sea,with weekly monitoring of changes in macrofouling species on mesh nets and in the seawater,to assess the utility of water eDNA metabarcoding for identifying macrofoulers.We compared the temporal variation patterns in the composition and diversity of macrofouling communities identified through morphological method as well as COI and 18S rRNA metabarcoding.The results showed that metabarcoding detected the majority of macrofoulers identified through morphological method(64%),and revealed additional species that were overlooked by traditional monitoring approach.Furthermore,the changes in diversity and community composition over sampling dates in COI data were generally consistent with those in morphological identification,although a temporal lag existed between these two approaches.A notable shift in the fouling community occurred at the end of June with the appearance of Ectopleura crocea and Caprella sp.,marking a pivotal change in its structure.Future research could focus on developing targeted primers for these key fouling species,which would enhance the efficiency of monitoring efforts.
基金supported by National Key R&D Program of China(2024YFA1107800)National Natural Science Foundation of China(Grant No.52403205,82172408,82425035 and 9236810338)+8 种基金Shanghai Jiao Tong University Medical College“Two-hundred Talent”Program(No.20191829)Program of Shanghai Academic/Technology Research Leader(No.22XD1422600)Shanghai Municipal Health Commission(No.2022YQ073)The Second Three-Year Action Plan for Promoting Clinical Skills and Clinical Innovation in Municipal Hospitals of Shanghai Shenkang(No.SHDC2020CR4032)Original Exploration project of Shanghai Science and Technology Innovation Action Plan(No.22ZR1480300)Shanghai“Medical Star”Young Medical Talent Training Funding Program(Outstanding Youth)Shanghai Health Commission Health Industry Research Project(Excellent Project)Shanghai Municipal Health Commission Research Project(No.20234Z0008)Foundation of Muyuan Laboratory(Program ID:13166022401).
文摘Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of the TCA cycle,emerges as a promising candidate for regulating energy metabolism.However,sus-tainable methods in providing energy metabolic substrates across the whole regenerating process has been neglected.Herein,a metabotissugenic membrane con-sisting of poly(octamethylene citrate)and L-lysine diisocyanate,POCL_(10),was developed to consistently biodegrade and provide citrate substrates.Furthermore,the POCL_(10) membrane exhibited self-sealing properties due to the introduction of strong hydrogen bonds and demonstrated anti-biofouling capacity in vitro.Intrigu-ingly,POCL_(10) showed excellent regenerative capability by promptly upregulating TSPC proliferation,energy metabolism and differentiation.In vivo,POCL_(10) was effortlessly wrapped around the injured Achilles tendon showcasing with anti-tissue adhesion and prominent collagen organization along with strengthened biomechanical properties.Hence,the development of POCL expands the reservoir of available biodegradable citrate-based biomaterials and provides a unique metabotissugenic biomaterial platform for tendon anti-biofouling and repair.
