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Biodegradation Of Polymers By Bacteria Isolated From Marine Environment

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Biological degradation is generally considered as a phenomenon of biological transformation of organic compounds by living organisms particularly microbes especially bacteria or fungi. The presence of plastic or polymer wastes in the environment brings about a challenge to wastewater treatment plants and pollution of groundwater and surface water. This work dedicated on the rise process of biodegradation by some synthetic polymers obtained from Plastic bottle waste and Polyvinyl Alcohol (PVA) which are non-biodegradable. In this study, bacteria have been isolated from the marine areas of Southern Bengal (two types of identified bacterial strains: Vibrio sp 1 from Frazerganj (Genbank accession no: KY828222.1, strain UR 1), and Vibrio sp 2 from Bakkhali (Genbank accession no: KY941137.1, strain PD 6) have been used for degrading Plastic bottle waste strips and PVA strips. These polymer film strips were degraded by the different bacterial strains by the weight loss and spectrophotometric analysis. The results indicated that the PVA sample lost its weight by 50 % and the sample from plastic bottle waste lost 40% of weight. Hence there are various polythene degradation methods available but the eco-friendly and acceptable method is by using microbes.


Degradation of plastics in marine environment is been considered as undesirable attribute as it shortens life span of a product and its durability. Recently, consciousness of the environmental problems by plastic waste as durable material has made biodegradable plastics an attractive alternative to conventional plastic materials. The study of plastic degradation was specified in using polymers and creating awareness for using plastic wastes on environmental hazards. Generally plastic bags and plastic polymers are quiet extensively used mainly for their cost effectiveness and for their large-scale production (Adane et al, 2011).

In this review work was carried out on biodegradability of polymers by using microorganisms and the polymers are natural and synthetic types. Disposal methods were used for the biodegradation of polymers. Numbers of test were used for the determination of biodegradation of microorganism. Many of the microbes are active at aerobically or some anaerobically. In experimental work weight loss of polymer, physical, chemical properties were measured. (Shaha et al, 2008).

The paper review found that bacterial strains from Frazerganj (Vibrio sp, Genbank accession no: KY828222.1, strain UR1) and Bakkhali (Vibrio sp., Genbank accession no: KY941137.1 , strain PD6) were natural to the places of plastic removal and indicate definite decomposability in regular situations and so similarly biodegradation in laboratory situations on minimal and Nutrient agar media. Conferring to this review bacteria cause highest degradation of polymers and plastics (Singh, et al, 2012).

In this research paper the isolation and characterization of plastic polymer degrading bacteria from plastic waste was done. Bacterial strains were successfully isolated from marine areas of Southern Bengal. The identified bacterial species were Vibrio sp 1 from Frazerganj(Genbank accession no : KY828222.1, strain UR1) and Vibrio sp 2 from Bakkali (Genbank accession no : KY941137.1, strain PD6) . The degradation was observed by changes in its characteristics. The percentage of weight loss analysis suggested that Vibrio sp. 2 degraded the plastic maximum and the degradation was observed anaerobically. The maximum amounts of plastic polymer degradation by weight loss method were observed (Pande et al., 2014).

Thus, the most effective way of biodegradable plastics is by the process of bioremediation which enhances on not accumulating the various hazardous chemicals to be replenished as environmental pollutants and to overcome the problems embellished by different efficient and durable plastic wastes.


The materials used for this research study is as follows:

Plastic bottle waste was procured from solid waste litter site, the commonly used polymer Polyvinyl Alcohol (PVA) was synthesized in laboratory.

For minimal media preparation, potassium dihydrogen phosphate (KH2PO4), sodium nitrate (NaNO3), magnesium sulphate heptahydrate (MgSO4.7H2O), potassium chloride (KCl), ferrous sulphate heptahydrate (FeSO4.7H2O) and ammonium chloride (NH4Cl) was procured from Lobachemie, India.


Preparation of PVA

4 g of PVA granules were dissolved in 75 mL of water by heating at 95°C under moderate stirring for about 2 hrs. After 2 hrs, the PVA solution was casted on a sterile petri dish and then was cut into small uniform pieces to use in the biodegradation process.

Biodegradation study using bacterial strains

Biodegradation behaviour of the different polymer film samples was examined by the rate of degradation through marine microbes, namely different species of identified bacterial strains: Vibrio sp 1(Genbank accession no: KY828222.1 , strain UR1) (Frazerganj sp)., and Vibrio sp 2 (Genbank accession no : KY941137.1 , strain PD6) (Bakkhali sp.). The bacterial strains were isolated from the marine waters near Southern Bengal area. The first film sample was Plastic bottle waste obtained by cutting the Kinley mineral water bottle into square sized 1 cm diameter. The second film sample was PVA (Polyvinyl Alcohol), obtained by the process discussed above and then was cut into small uniform pieces. The polymer films samples were taken out at 1, 2, 3, 4, 5 and 6 weeks for plastic bottle wastes, and for PVA samples respectively, washed with ethanol, vacuum dried and thus percentage of weight loss of the samples with respect to biodegradation was examined.

Weight Loss Analysis

The characterization of the various types of polymer films can be calculated by the weight loss study measuring the rate of degradation at different time intervals from the minimal media, Plastic bottle wastes were taken out after keeping it for 6 weeks and PVA was taken out after keeping it for 4 weeks at an incubator temperature of about 36-37°C hence calculating the percentage of weight loss by the given equation,

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%Weight loss = {(T1-T2)/T1} * 100

Where, T1 is the initial weight of the polymer samples before biodegradation (before putting it in media) and T2 is the final weight of the polymer samples after biodegradation (after taking out from media) at different time intervals

Fixation of the bacterial isolate for SEM Analysis

Glutaraldehyde and ethanol were obtained from Merck, Germany, for fixation of the bacterial isolates on the polymer film surfaces (Plastic bottle waste and PVA film). The fixation was done by the following procedure:

2.5% glutaraldehyde was taken followed by 0.1 M PBS (Phosphate buffer saline) solution and dehydration by using varied concentrations of ethanol: 30%, 70% and 100% respectively and the incubation time for the polymer films was 10 mins in each of the solution and then finally were dried and examined for SEM analysis (Carl Zeiss). SEM analysis was done to identify the morphological changes in the polymer structures. All the samples were provided with vacuum and coated with platinum and polymer structures with fixed bacterial strains were observed on the film surfaces.


Weight loss study of the Plastic bottle wastes and Polymer PVA (Polyvinyl Alcohol)

The rate of degradation was studied as the weight loss study of the films were evaluated by the graph as a function of biodegradation time obtained from the study of growth of the bacterial strains on the plastic polymer samples in fig. 2(A, and B). PVA sample strips showed a higher % of weight loss as compared to plastic bottle waste. This study reflects a higher weight loss of polymer PVA with respect to the plastic bottle waste. The plastic bottle waste films showed a higher weight loss after 6 weeks and the PVA polymer sample films showed an effective percentage of weight loss after 4 weeks, (Plastic bottle waste around 32% and PVA polymer around 35%).

EM Analysis of the degraded polymer film surfaces fixed with glutaraldehyde

After the comparison of two bacteria, we can notice that Vibrio sp2 from Bakkhali shows a better degradation as compared to Vibrio sp1 from Frazergunj. Hence, we performed the SEM (Scanning Electron Microscopy) analysis using vibrio sp2.

SEM analysis technique allows examining of changes in the morphology of materials at the micro scale. In order to perceive the changes in the structure of the samples, images from the SEM were used. Surface morphology by scanning electron microscopy was determined. The experiment involved images of both the original samples and samples that underwent biodegradation process. SEM analysis exhibited the microbial activity of degradation on the bioplastic samples (Fig 4: A, B, C, D). The growth of the microorganism by the degradation process was clearly visualized under SEM. The surface structure of the material had lost its smoothness, and cracks were evident. The samples showed a significant change in the structure. SEM images confirmed the biodegradation process of the polymer samples.

Fig represents SEM images of the different surfaces of the polymer films after and before degradation. The films before degradation shows a smoother surface compared to the films after degradation which shows a rougher surface. For further study and identification of biodegradation behaviour of the polymer films, SEM analysis of the films with 2.5% glutaraldehyde solution was carried out. The polymer films in minimal media, from which it was isolated were kept under an incubation period of 6 weeks after which the SEM analysis was done.

Effect of temperature on the polymer films

The different polymer films (Plastic bottle waste and PVA) with the bacterial strains were kept under an incubation period of 3 weeks at varied temperatures: 25°C, 35°C and 45°C so as to investigate the best temperature for the polymer films and we can say that 35°C is the best optimum temperature for the growth of bacteria.

Effect of pH on the polymer films by the bacterial strains

The polymer films with the bacterial isolates after kept at an incubation period of 2 weeks were studied for different pH: 1,3,9,11. As pH increases, rate of degradation increases since bacterial growth takes place best at alkaline pH.

Effect of inoculum dose on the polymer films

The plastic polymer films of bottle waste and PVA inoculated with the different bacterial strains were kept for incubation for 2 weeks with different inoculum concentrations of 1ml, 3 ml, 5 ml and 7 ml respectively. Hence, we can evaluate that the higher concentrations results in higher rate of degradation.


The present study deals with the influence of different plastic polymer samples like Plastic bottle wastes and Polyvinyl Alcohol (PVA) on the biological degradation using microbial strains, (two types of bacterial strains: Vibrio sp 1(Genbank accession no: KY828222.1, strain UR1) (Frazergunj sp.) and Vibrio sp 2 (Genbank accession no : KY941137.1, strain PD6) (Bakkhali sp.). The degradation can be evaluated by the weight loss method and spectrophotometric analysis. The results indicated that the rate of degradation by PVA sample strips was more as compared to the degradation by Plastic bottle waste strips since the PVA showed a higher and effective percentage of weight loss as compared to the Plastic bottle waste. Thus, the methods showed that microbial degradation is an efficient way for different plastic polymers.


  1. Shah Amir Ali, Hasan Fariha, Hameed Abdul, Ahmed Safia, (Journal of Biotechnology Advances), (January 2012), (volume 26), “Biological Degradation of plastics: a comprehensive review”, (246-65).
  2. Merina Paul Das, Santosh Kumar, (Journal 3 Biotech), (February 2015), (volume 5) “An Approach to Low density Polyethylene Biodegradation by Bacillus amyloloquefaciens”, (81-86).
  3. Gauri Singh, Ashok Kumar Singh, Kalpana Bhatt, (International Journal of Research and Development in Pharmacy and Life Sciences), (December 2015), (volume 5), “Biodegradation of Polythenes By Bacteria Isolated from Soil “, (2056-2062).
  4. Pramod K Pandey, Philip H Kass, Michelle L Soupir, Sagor Biswas, Vijaya P Singh, (International Journal of Biotechnology), (May 2014), (volume 10) “Contamination of Water resources By Pathogenic bacteria”, (451-568).
  5. Swapan Kumar Ghosh, Sujoy Pal, Sumanta Ray, (International Journal of Environmental Science and Pollution), (April 2013), (volume 20), “Study of microbes having potentiability for biodegradation of plastics” (4339-4355).
  6. Manisha K Sangale, Mohd Shahnawaz and Avinash B Ade, (Journal of Bioremediation and Biodegradation), (2012), (volume 10), “A Review on Biodegradation of Polythene: The Microbial Approach”, (2155-6199)

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Biodegradation Of Polymers By Bacteria Isolated From Marine Environment. (2022, February 21). Edubirdie. Retrieved December 5, 2022, from
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