1
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Liu Z, Kimyon O, Manefield M. Wastewater treatment bacteria show differential preference for colonizing natural biopolymers. Appl Microbiol Biotechnol 2024; 108:321. [PMID: 38709299 DOI: 10.1007/s00253-024-13162-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/07/2024]
Abstract
Most reduced organic matter entering activated sludge systems is particulate (1-100-µm diameter) or colloidal (0.001-1-µm diameter), yet little is known about colonization of particulate organic matter by activated sludge bacteria. In this study, colonization of biopolymers (chitin, keratin, lignocellulose, lignin, and cellulose) by activated sludge bacteria was compared with colonization of glass beads in the presence and absence of regular nutrient amendment (acetate and ammonia). Scanning electron microscopy and quantitative PCR revealed chitin and cellulose were most readily colonized followed by lignin and lignocellulose, while keratin and glass beads were relatively resistant to colonization. Bacterial community profiles on particles compared to sludge confirmed that specific bacterial phylotypes preferentially colonize different biopolymers. Nitrifying bacteria proved adept at colonizing particles, achieving higher relative abundance on particles compared to bulk sludge. Denitrifying bacteria showed similar or lower relative abundance on particles compared to sludge. KEY POINTS: • Some activated sludge bacteria colonize natural biopolymers more readily than others. • Nitrifying bacteria are overrepresented in natural biopolymer biofilm communities. • Biopolymers in wastewater likely influence activated sludge community composition.
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Affiliation(s)
- Zongzong Liu
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, 2052, Australia
| | - Onder Kimyon
- School of Civil and Environmental Engineering, University of New South Wales (UNSW), Sydney, 2052, Australia
| | - Mike Manefield
- School of Civil and Environmental Engineering, University of New South Wales (UNSW), Sydney, 2052, Australia.
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2
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Chigwada AD, Tekere M. The plastic and microplastic waste menace and bacterial biodegradation for sustainable environmental clean-up a review. ENVIRONMENTAL RESEARCH 2023; 231:116110. [PMID: 37172684 DOI: 10.1016/j.envres.2023.116110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 05/06/2023] [Accepted: 05/10/2023] [Indexed: 05/15/2023]
Abstract
Environment plastic litter accumulation is a significant concern, needing urgent advancements in plastic waste management. Recent investigations into plastic biodegradation by bacteria and their enzymes are creating exciting unique opportunities for the development of biotechnological plastic waste treatment methods. This review summarizes information on bacterial and enzymatic biodegradation of plastic in a wide range of synthetic plastics such as polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyurethane (PUR), polytetrafluoroethylene (PTFE) and polyvinyl chloride (PVC). Plastic biodegradation is facilitated by Acinetobacter, Bacillus, Brevibacillus, Escherichia, Pseudomonas, Micrococcus, Streptomyces, and Rhodococcus bacteria, and enzymes such as proteases, esterases, lipases, and glycosidases. Molecular and analytical procedures used to analyze biodegradation processes are outlined, as are the obstacles in verifying plastic breakdown using these methods. Taken together, the findings of this study will contribute significantly to the construction of a library of high-efficiency bacterial isolates and consortiums and their enzymes for use in plastic biosynthesis. This information is useful to researchers investigating plastic bioremediation and a supplement to the scientific and grey literature already accessible. Finally, the review focuses on expanding the understanding of bacterial capacity to break-down plastic utilizing modern biotechnological methods, bio-nanotechnological-based materials, and their future role in resolving pollution problems.
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Affiliation(s)
- Aubrey Dickson Chigwada
- Department Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa (UNISA), Florida Campus, Roodepoort, 1709, South Africa
| | - Memory Tekere
- Department Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa (UNISA), Florida Campus, Roodepoort, 1709, South Africa.
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3
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Fate of Biofilm Activity in Cascade Aerating Trickling Filter for Wastewater Treatment: Comparison of Two Types of Indigenous Support Media. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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4
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Zhang Y, Pedersen JN, Eser BE, Guo Z. Biodegradation of polyethylene and polystyrene: From microbial deterioration to enzyme discovery. Biotechnol Adv 2022; 60:107991. [PMID: 35654281 DOI: 10.1016/j.biotechadv.2022.107991] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/10/2022] [Accepted: 05/26/2022] [Indexed: 11/24/2022]
Abstract
The global production of plastics has continuously been soaring over the last decades due to their extensive use in our daily life and in industries. Although synthetic plastics offer great advantages from packaging to construction and electronics, their low biodegradability induce serious plastic pollution that damage the environment, human health and make irreversible changes in the ecological cycle. In particular, plastics containing only carbon-carbon (C-C) backbone are less susceptible to degradation due to the lack of hydrolysable groups. The representative polyethylene (PE) and polystyrene (PS) account for about 40% of the total plastic production. Various chemical and biological processes with great potential have been developed for plastic recycle and reuse, but biodegradation seems to be the most attractive and eco-friendly method to combat this growing environmental problem. In this review, we first summarize the current advances in PE and PS biodegradation, including isolation of microbes and potential degrading enzymes from different sources. Next, the state-of-the-art techniques used for evaluating and monitoring PE and PS degradation, the scientific toolboxes for enzyme discovery as well as the challenges and strategies for plastic biodegradation are intensively discussed. In return, it inspires a further technological exploration in expanding the diversity of species and enzymes, disclosing the essential pathways and developing new approaches to utilize plastic waste as feedstock for recycling and upcycling.
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Affiliation(s)
- Yan Zhang
- Department of Biological and Chemical Engineering, Aarhus University, 8000 Aarhus, Denmark
| | | | - Bekir Engin Eser
- Department of Biological and Chemical Engineering, Aarhus University, 8000 Aarhus, Denmark
| | - Zheng Guo
- Department of Biological and Chemical Engineering, Aarhus University, 8000 Aarhus, Denmark.
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Singh Jadaun J, Bansal S, Sonthalia A, Rai AK, Singh SP. Biodegradation of plastics for sustainable environment. BIORESOURCE TECHNOLOGY 2022; 347:126697. [PMID: 35026422 DOI: 10.1016/j.biortech.2022.126697] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/31/2021] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
Plastics are a kind of utility product that has become part and parcel of one's life. Their continuous usage, accumulation, and contamination of soil and water pose a severe threat to the biotic and abiotic components of the environment. It not only increases the carbon footprints but also contributes to global warming. This calls for an urgent need to develop novel strategies for the efficient degradation of plastics. The microbial strains equipped with the potential of degrading plastic materials, which can further be converted into usable products, are blessings for the ecosystem. This review comprehensively summarizes the microbial technologies to degrade different plastic types, such as polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl chloride (PVC), polypropylene (PP), and polyurethane (PU). The study also describes the utilization of degraded plastic material as feedstock for its conversion into high-value chemicals.
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Affiliation(s)
- Jyoti Singh Jadaun
- Department of Botany, Dayanand Girls Postgraduate College, Kanpur 208001, Uttar Pradesh, India
| | - Shilpi Bansal
- ICAR-Indian Agricultural Research Institute, Pusa, New Delhi 10012, India
| | - Ankit Sonthalia
- SRM Institute of Science and Technology, NCR Campus, Modi Nagar- 201204, Ghaziabad, Uttar Pradesh, India
| | - Amit K Rai
- Institute of Bioresources and Sustainable Development, Regional Centre, Tadong, Sikkim, India
| | - Sudhir P Singh
- Center of Innovative and Applied Bioprocessing, SAS Nagar, Mohali-140306, Punjab, India.
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Kotova IB, Taktarova YV, Tsavkelova EA, Egorova MA, Bubnov IA, Malakhova DV, Shirinkina LI, Sokolova TG, Bonch-Osmolovskaya EA. Microbial Degradation of Plastics and Approaches to Make it More Efficient. Microbiology (Reading) 2021. [DOI: 10.1134/s0026261721060084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Abstract—
The growing worldwide production of synthetic plastics leads to increased amounts of plastic pollution. Even though microbial degradation of plastics is known to be a very slow process, this capacity has been found in many bacteria, including invertebrate symbionts, and microscopic fungi. Research in this field has been mostly focused on microbial degradation of polyethylene, polystyrene, and polyethylene terephthalate (PET). Quite an arsenal of different methods is available today for detecting processes of plastic degradation and measuring their rates. Given the lack of generally accepted protocols, it is difficult to compare results presented by different authors. PET degradation by recombinant hydrolases from thermophilic actinobacteria happens to be the most efficient among the currently known plastic degradation processes. Various approaches to accelerating microbial plastic degradation are also discussed.
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Naresh Yadav D, Naz I, Anand Kishore K, Saroj D. Evaluation of tire derived rubber (TDR) fixed biofilm reactor (FBR) for remediation of Methylene blue dye from wastewater. ENVIRONMENTAL TECHNOLOGY 2021; 42:3627-3640. [PMID: 32114965 DOI: 10.1080/09593330.2020.1737736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 02/24/2020] [Indexed: 06/10/2023]
Abstract
The present investigation is focused on development of aerobic biofilm on tire-derived rubber (TDR) media and then evaluation of such system for bioremediation of Methylene blue (MB) dye for 9 weeks. After 9 weeks of operation, the COD, BOD, ammonia and color values have been declined by 89.2%, 98.3%, 99.61% and 99.81%, respectively, While SEM-EDX results showed a variance in weight percent of various elements in TDR without biofilm i.e. raw TDR media, as well as in the 1st and 9th-week samples. Moreover, fine and strong peaks were observed in both the MB simulated wastewater and 9th week TDR samples at 1190, 1300, 1400, 1450, 1500 and 1618 cm-1 respectively by Raman Spectroscopic analysis. Further, FTIR analysis was performed for the MB simulated wastewater, and absorbance peaks ranging from 1591 to 1363 cm-1 and 3410 cm-1 were observed in all the samples with different intensities. To assess the biodeterioration of the TDR media, ATR was performed for the raw, 1st, 2nd and 9th week TDR media samples and in the raw TDR, two important bands, 842 and 2962 cm-1 were noticed representing -CH = CH and -CH3. A clear variation of bands and peak intensities were observed in different support media samples. The results indicate that TDR media is a resilient, chemically resistant material and could be employed for the biofilm growth for biological treatment of textile dye wastewater.
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Affiliation(s)
- D Naresh Yadav
- Department of Chemical Engineering, National Institute of Technology, Warangal, India
- Faculty of Engineering and Physical Sciences, Department of Civil and Environmental Engineering, University of Surrey, Surrey, UK
| | - Iffat Naz
- Faculty of Engineering and Physical Sciences, Department of Civil and Environmental Engineering, University of Surrey, Surrey, UK
- Department of Biology, Deanship of Educational Services, Qassim University, Buraidah, Saudi Arabia
| | - K Anand Kishore
- Department of Chemical Engineering, National Institute of Technology, Warangal, India
| | - Devendra Saroj
- Faculty of Engineering and Physical Sciences, Department of Civil and Environmental Engineering, University of Surrey, Surrey, UK
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8
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Donkadokula NY, Naz I, Kola AK, Saroj D. Assessment of the aerobic glass beads fixed biofilm reactor (GBs-FBR) for the treatment of simulated methylene blue wastewater. Sci Rep 2020; 10:20705. [PMID: 33244058 PMCID: PMC7692555 DOI: 10.1038/s41598-020-77670-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 11/09/2020] [Indexed: 11/19/2022] Open
Abstract
The present research is focused on the application of glass beads (GBs) in fixed biofilm reactor (FBR) for the treatment of simulated methylene blue (MB) wastewater for 9 weeks under aerobic conditions. The COD of MB wastewater showed a reduction of 86.48% from 2000 to 270.4 mg/L, and BOD was declined up to 97.7% from 1095.5 to 25.03 mg/L. A drastic increase in the pH was observed until the 3rd week (8.5 to 8.28), and later, marginal changes between 8.30 ± 0.02 were noticed. A dramatic fluctuation was observed in ammonia concentration which increased (74.25 mg/L) up till the 2nd week, and from the 3rd week it started declining. In the 9th week, the ammonia concentration dropped to 16.5 mg/L. The color intensity increased significantly up till the 2nd week (259,237.46 Pt/Co) of the experiment and started decreasing slowly thereafter. The SEM-EDX analysis has shown the maximum quantity of carbon content in the GBs without biofilm, and then in the GB samples of 1st, and 9th-week old aerobic biofilms. Furthermore, Raman spectroscopy results revealed that the 9th-week GBs has a fine and strong MB peak and matched with that of the MB stock solution. Overall, the results have shown that the GBs filter media were suitable for the development of active biofilm communities for the treatment of dye wastewater. Thus, GBs-FBR system can be used for wastewater treatment to solve the current problem of industrial pollution in many countries and to protect the aquatic environment from dye pollution caused by the textile industry.
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Affiliation(s)
- Naresh Yadav Donkadokula
- Department of Chemical Engineering, National Institute of Technology Warangal, Warangal, Telangana, India
- Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
| | - Iffat Naz
- Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
- Department of Biology, Scientific Unit, Deanship of Educational Services, Qassim University, Buraidah, 51452, Kingdom of Saudi Arabia
| | - Anand Kishore Kola
- Department of Chemical Engineering, National Institute of Technology Warangal, Warangal, Telangana, India.
| | - Devendra Saroj
- Centre for Environmental Health and Engineering (CEHE), Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
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9
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Raddadi N, Fava F. Biodegradation of oil-based plastics in the environment: Existing knowledge and needs of research and innovation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 679:148-158. [PMID: 31082589 DOI: 10.1016/j.scitotenv.2019.04.419] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/25/2019] [Accepted: 04/27/2019] [Indexed: 05/26/2023]
Abstract
The production of synthetic oil-based plastics has led to the accumulation of huge amounts of the plastic waste in the environment, especially in the marine system, very often the final sink for many types of conventional wasted plastics. In particular, (micro)plastics account for the majority of litter items in the marine environment and a high percentage of such litter is originating from land sources. Attempts to mitigate the harmful effects of conventional plastics such as the development of novel management strategies together with the gradual substitution of them with biodegradable (bio)plastics are representing future solutions. However, high amounts of conventional plastics have been accumulating in the environment since several years. Although many studies reported on their potential biodegradation by microbes in and from terrestrial environments, very little is known about the biodegradability of these plastics in freshwater systems and only recently more reports on their biodegradation by marine microorganisms/in marine environment were made available. In this review, we first provide a summary of the approaches applied for monitoring and assessing conventional plastics biodegradation under defined conditions. Then, we reviewed historical and recent findings related to biodegradation of four major plastics produced in European Union (EU), i.e. Polyethylene, Polyvinyl Chloride, Polypropylene and Polystyrene, in terrestrial and aquatic environments and by pure and mixed microbial cultures obtained from them.
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Affiliation(s)
- Noura Raddadi
- Department of Civil, Chemical, Environmental and Materials Engineering; Alma Mater Studiorum-University of Bologna, Italy.
| | - Fabio Fava
- Department of Civil, Chemical, Environmental and Materials Engineering; Alma Mater Studiorum-University of Bologna, Italy
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10
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Ho BT, Roberts TK, Lucas S. An overview on biodegradation of polystyrene and modified polystyrene: the microbial approach. Crit Rev Biotechnol 2017; 38:308-320. [DOI: 10.1080/07388551.2017.1355293] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Ba Thanh Ho
- Faculty of Environment and Natural Resources, Nong Lam University, Ho Chi Minh City, Vietnam
| | - Timothy K. Roberts
- The Tom Farrell Institute for The Environment, University of Newcastle, Newcastle, NSW, Australia
| | - Steven Lucas
- The Tom Farrell Institute for The Environment, University of Newcastle, Newcastle, NSW, Australia
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11
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Next-generation pyrosequencing analysis of microbial biofilm communities on granular activated carbon in treatment of oil sands process-affected water. Appl Environ Microbiol 2015; 81:4037-48. [PMID: 25841014 DOI: 10.1128/aem.04258-14] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 03/30/2015] [Indexed: 11/20/2022] Open
Abstract
The development of biodegradation treatment processes for oil sands process-affected water (OSPW) has been progressing in recent years with the promising potential of biofilm reactors. Previously, the granular activated carbon (GAC) biofilm process was successfully employed for treatment of a large variety of recalcitrant organic compounds in domestic and industrial wastewaters. In this study, GAC biofilm microbial development and degradation efficiency were investigated for OSPW treatment by monitoring the biofilm growth on the GAC surface in raw and ozonated OSPW in batch bioreactors. The GAC biofilm community was characterized using a next-generation 16S rRNA gene pyrosequencing technique that revealed that the phylum Proteobacteria was dominant in both OSPW and biofilms, with further in-depth analysis showing higher abundances of Alpha- and Gammaproteobacteria sequences. Interestingly, many known polyaromatic hydrocarbon degraders, namely, Burkholderiales, Pseudomonadales, Bdellovibrionales, and Sphingomonadales, were observed in the GAC biofilm. Ozonation decreased the microbial diversity in planktonic OSPW but increased the microbial diversity in the GAC biofilms. Quantitative real-time PCR revealed similar bacterial gene copy numbers (>10(9) gene copies/g of GAC) for both raw and ozonated OSPW GAC biofilms. The observed rates of removal of naphthenic acids (NAs) over the 2-day experiments for the GAC biofilm treatments of raw and ozonated OSPW were 31% and 66%, respectively. Overall, a relatively low ozone dose (30 mg of O3/liter utilized) combined with GAC biofilm treatment significantly increased NA removal rates. The treatment of OSPW in bioreactors using GAC biofilms is a promising technology for the reduction of recalcitrant OSPW organic compounds.
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12
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Douterelo I, Boxall JB, Deines P, Sekar R, Fish KE, Biggs CA. Methodological approaches for studying the microbial ecology of drinking water distribution systems. WATER RESEARCH 2014; 65:134-156. [PMID: 25105587 DOI: 10.1016/j.watres.2014.07.008] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/08/2014] [Accepted: 07/04/2014] [Indexed: 06/03/2023]
Abstract
The study of the microbial ecology of drinking water distribution systems (DWDS) has traditionally been based on culturing organisms from bulk water samples. The development and application of molecular methods has supplied new tools for examining the microbial diversity and activity of environmental samples, yielding new insights into the microbial community and its diversity within these engineered ecosystems. In this review, the currently available methods and emerging approaches for characterising microbial communities, including both planktonic and biofilm ways of life, are critically evaluated. The study of biofilms is considered particularly important as it plays a critical role in the processes and interactions occurring at the pipe wall and bulk water interface. The advantages, limitations and usefulness of methods that can be used to detect and assess microbial abundance, community composition and function are discussed in a DWDS context. This review will assist hydraulic engineers and microbial ecologists in choosing the most appropriate tools to assess drinking water microbiology and related aspects.
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Affiliation(s)
- Isabel Douterelo
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, UK.
| | - Joby B Boxall
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, UK
| | - Peter Deines
- Institute of Natural and Mathematical Sciences, Massey University, New Zealand
| | - Raju Sekar
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, China
| | - Katherine E Fish
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, UK
| | - Catherine A Biggs
- Department of Chemical and Biological Engineering, The University of Sheffield, UK
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Khatoon N, Naz I, Ali MI, Ali N, Jamal A, Hameed A, Ahmed S. Bacterial succession and degradative changes by biofilm on plastic medium for wastewater treatment. J Basic Microbiol 2013; 54:739-49. [PMID: 24115187 DOI: 10.1002/jobm.201300162] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 07/13/2013] [Indexed: 12/14/2022]
Abstract
Biofilms contain a diverse range of microorganisms and their varying extracellular polysaccharides. The present study has revealed biofilm succession associated with degradative effects on plastic (polypropylene) and contaminants in sludge. The wet weight of biofilm significantly (p < 0.05) increased; from 0.23 ± 0.01 to 0.44 ± 0.01 g. Similarly, the dry weight of the biofilm increased from 0.02 to 0.05 g. Significant reduction in pathogens (E. coli and feacal coliforms) by MPN technique (>80%) and in chemical parameters (decrease in COD, BOD5 of 73.32 and 69.94%) representing diminution of organic pollutants. Energy dispersive X-ray spectroscopy (EDS) of plastic revealed carbon and oxygen contents, further surface analysis of plastic by scanning electron microscopy (SEM) revealed emergence of profound bacterial growth on the surface. Fourier transform infrared (FTIR) spectroscopy conforms its biotransformation under aerobic conditions after 8 weeks. New peaks developed at the region 1050 and 969 cm(-1) indicating CO and CC bond formation. Thus plastic with 6 weeks old aerobic biofilm (free of pathogens, max. weight, and OD, efficient COD & BOD removal ability) is suggested to be maintained in fixed biofilm reactors for wastewater treatment.
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Affiliation(s)
- Nazia Khatoon
- Microbiology Research Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
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