A Review: Plastics Waste Biodegradation Using Plastics-Degrading Bacteria

Journal of Environmental Treatment Techniques

2021, Volume 9, Issue 1, Pages: 148-157

J. Environ. Treat. Tech.

ISSN: 2309-1185

Journal web link: http://www.jett.dormaj.com

https://doi.org/10.47277/JETT/9(1)157

A Review: Plastics Waste Biodegradation Using

Plastics-Degrading Bacteria

Angga Puja Asiandu *, Agus Wahyudi , Septi Widiya Sari

Department of Biology, Gadjah Mada University, Yogyakarta, Indonesia

Department of Biology, Sriwijaya University, Indonesia

Department of Sociology, University of Bengkulu, Indonesia

Received: 25/09/2020

Accepted: 25/10/2020

Published: 20/03/2021

Abstract

Plastic is a synthetic polymer that is widely used in almost every field of life. The massive use of this synthetic polymer has led to the

accumulation of this polymer in the environment thus polluting the environment. The general techniques in preventing plastic waste as

landfill, incineration, recycling are considered less effective as they release some hazardous materials to the environment. Thus, the

appropriate technique is needed to overcome this problem. Biodegradation is an enzymatic degradation involving some microorganisms

including bacteria. This technique can be used to prevent the plastic waste problem. Plastic waste biodegradation occurred through several

steps, including biodeterioration, depolymerization, and assimilation. Within this process, bacteria will secrete many enzymes that will

degrade and convert plastic polymers into microbial biomass and gases. Thus, this process has fewer even no side effect.

Keywords: Bacteria, Biodegradation, Enzymes, Plastics Waste

Plastics are daily lives related products used in almost every

Introduction

field of life in all countries (9). They are widely used because of

their strength and durability. On the other hand, those characters

lead to plastic resistance to degradation. These insoluble

recalcitrant polymers take many years to be naturally degraded

in the environment. This problem encourages plastic waste

pollution that threatens many living things, including humans

Plastics are organic polymers containing molecules

composed of long carbon chains back-bone formed through the

polymerization (1). They are made of carbon and hydrogen, with

nitrogen, sulfur, and other various organic and inorganic

materials derived from fossil fuels (2). Plastics divided into

natural plastics, semi-synthetic plastics, synthetic plastics,

thermoplastics, and thermosetting plastics (3).

(

10).

The uncontrolled plastics uses started several decades ago

The massive plastics production has begun in the 1950s,

which is generally produced for disposable use. Most of the

plastics waste is non-biodegradable which takes thousands of

years to be decomposed or degraded (4). In 2010, China was the

highest plastic waste producer in the world with 8.8 million tons

per year or 27% of the total world plastic waste production.

Meanwhile, Indonesia was the second after China as the highest

plastic waste-producing country in the world with 3.2 million

tons per year or 10% of the total world plastic waste (5, 6, 4). In

Indonesia, approximately 15% of the individually daily wastes

are plastics (7). Based on the European Plastics in 2018, total

world plastic production reaches 335 million tons per year, as

much as 60 million of that amount is obtained in Europe. It is

estimated that the number of plastic productions will be two

times greater in the next 20 years. Meanwhile, plastic bags are

the most common form of plastic widely used in daily lives in

the world. Although plastic products are reusable, they are still

one of the main factors causing environmental pollution (8).

have caused many environmental problems related to the

disposal uses and pollutions of plastics waste. The

decomposition process of plastic polymers takes thousands of

years. People usually burn plastics waste to overcome the

accumulation of plastics waste in the environment yet the

burning of plastics waste leads to air pollution. It releases toxic

compounds, CO , and dioxins, into the air. Those released gases

cause lung diseases and cancer (11). As plastics waste is a

pollutant polluting the land, air, and water ecosystem (12),

threatening various living things (10), therefore the appropriate

processing method of plastic waste is necessarily needed to be

carried out. The application of reuse, reduce, and recycle is now

widely applied to prevent the problem caused by plastics waste.

However, this method is less effective, especially for plastics

waste that has been mixed with other types of waste (8). Also,

landfill plastics waste processing requires large space, and

incineration plastics waste processing can produce toxic gases

into the environment (13). Thus the more effective and

environmentally safe processing plastics waste method is

needed. Biodegradation is considered as a more profitable and

more effective method to prevent this worldwide problem.

Corresponding Author: Angga Puja Asiandu, Department of

Biology, Gadjah Mada University, Yogyakarta, Indonesia.

E-mail: anggahasiandu@gmail.com

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2021, Volume 9, Issue 1, Pages: 148-157

Biodegradation involves many kinds of plastics degrading

Plastics Waste Problems

microorganisms

(14,

15)

bacteria, such

The plastics degradation process in the environment takes up

0 to 100 years, even reaching 500 years to be degraded

D.nigrificans, and Pseudomonas alcaligenes (16). They can

produce various enzymes, both intracellular and extracellular,

that can degrade plastic polymers to protect the environment

completely (22). Furthermore, the degradation of plastic bags

and styrofoam containers spend 1000 years (4). It causes

negative impacts on the environment as decreasing soil fertility

that contaminated with plastics waste, contaminating water by

plastic constituents, interfering soil-decomposing organisms, and

accumulating toxic compounds through the food chains. Also,

buried plastic waste blocks waterways cause flooding (22).

Plastics waste in both terrestrial and aquatic environments is

the main problem of ecosystem balance. It will be worse when

the plastics have been transformed into invisible microplastics

that are harder to overcome. The large amount of plastics waste

dominated by plastic bags has caused various respiratory and

digestive system problems for thousands of species. Ingested

plastic waste by animals, mainly aquatic animals such as fish,

leads to bioaccumulation of the toxic compounds contained in

the plastic waste. Then the plastic contaminated fish possibly

consumed by humans resulting in many health problems. It is

estimated that in 2050 as many as 99% of seabirds will be

exposed to plastic waste through ingestion (4).

Plastics waste on the land can be broken down by sunlight

into smaller parts or fragments polluting soil and water. Those

toxic fragments may be involved in food chains threatening

many living things. For instance, polyethylene is gravely

hazardous for many aquatic species as aquatic mammals, sea

turtles, and waterbirds when it is consumed accidentally (11).

Plastics waste burning is not an effective solution to solve

plastics accumulation problems. That process releases toxic

gases into the environment including dioxins, heavy metals,

PCBs, and furans causing various respiratory system diseases

(

14, 15), and to stop plastics polluting the land, air, and water

10).

Type of Plastics

Plastics generally divided into two categories,

thermoplastics and thermosets. Thermoplastics are a group of

plastics that can be melted when heated and hardened when

cooled.

Thermoplastics

are

including

Polyethylene

Terephthalate (PET), Polyethylene (PE), Low-Density

Polyethylene (LDPE), High-Density Polyethylene (HDPE),

Polystyrene (PS), Expanded polystyrene (EPS), Polyvinyl-

chloride (PVC), Polycarbonate, Polypropylene (PP), Polylactic

acid (PLA) and Polyhydroxyalkanoates (PHA). Meanwhile,

thermosets are plastics which their chemical structures can be

changed when heated thus can not be re-melted. Thermoset

plastics are including Polyurethane (PUR), Phenolic resins,

Epoxy resins, Silicone, Vinyl ester, Acrylic resins,

Ureaformaldehyde (UF) resins (4).

Polyethylene terephthalate (PET) is a transparent and thin

plastic that commonly used as a wrapper for various foods and

drinks. Low-density polyethylene (LDPE) is a flexible and

strong heat-resistant plastic usually used as a drink container.

High-density polyethylene (HDPE), made from heat-resistant

petroleum, is commonly used as plastic bags. While Polyvinyl

chloride (PVC) is a synthetic plastic containing many chemical

additives such as heavy metals, dioxins, BPA, and phthalates

resulting in various health problems as bronchitis and cancer.

This plastic is widely used as a wrapper, such as vegetable oil

wrapper. Polypropylene (PP), strong and semi-permanent

plastic, commonly used for medicine packaging. Polystyrene

(23, 18). Furthermore, the plastic burning produces CO into the

air, the gas is related to global warming. It will trap solar heat

that increases the earth's surface temperature (24, 18).

(

PS) is a petroleum-based plastic that contains benzene, a

The accumulated plastics waste on the land is hard to

degrade. It will inhibit the water infiltration into the soil (11),

leads to soil infertility. The plastics waste accumulation on the

land reduces the availability of oxygen in the soil. The amount

of plastics waste in the soil causes the reduction of soil-

decomposing organisms, thus decomposition of organic and

inorganic materials will be decreased that affects the soil fertility

and inhibits plant growth (22).

carcinogenic compound. This plastic widely used as cutleries.

Polycarbonate is a plastic that contains hazardous BPA material,

this plastic is usually used as a reusable bottle (17, 18).

Meanwhile, the most common single-use plastics are LDPE,

HDPE, PET, PS, EPS, and PP (4).

Based on Plastic Europe 2018, In Europe, the highest plastic

demands are LDPE, HDPE, polypropylene, polyvinyl chloride,

polyurethane, polystyrene, and polyethylene terephthalate. The

need for LDPE is 17.5% and HDPE 12.3%. While the need for

polypropylene is 19.3%, polyvinyl chloride 10.2%, polyurethane

Plastics Hazardous Substances

Plastics contain some hazardous substances affecting human

(

.7%, polystyrene 7.4%, and polyethylene terephthalate is 7.4%

19).

In addition to nonbiodegradable synthetic plastics,

health. Dangerous plastic components such as bisphenol A

found in PC and PVC can cause the reproductive system

disorders, mainly the ovaries. Phthalates contained in PS and

PVC lead to testosterone disorders and interfere with sperm

motility. The styrene monomers as those found in polystyrene-

type plastics are carcinogenic. Nonylphenol contained in PVC

causes estrogen disorders. Meanwhile, dioxins, persistent

organic pollutants (POPs), polycyclic aromatic hydrocarbons

biodegradable plastics are now being developed and used.

Biodegradable plastics and polymers are materials that are now

widely used in various industries. The use of biodegradable

plastics is related to environmental problems due to the

recalcitrant characteristic of petroleum-based plastics waste.

Some biodegradable plastics are polylactic acid (PLA) and

polybutylene adipate-co-terephthalate (20, 21). Although PLA is

biodegradable, the polymer still requires a long time to be

degraded in nature. The complete biodegradation process of a

biodegradable polymer in nature takes months or even years

(

PAHs), and polychlorinated biphenyls (PCBs) found in almost

all plastic types resulting in various health problems. Dioxins are

carcinogens interfering with testosterone disorders. POPs can

disrupt the nervous and reproductive systems. PAHs associated

with the reproductive system and development disorders, and

PCBs related to thyroid hormone disorders (25, 18).

(

21).

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2021, Volume 9, Issue 1, Pages: 148-157

kinds of acid compounds changing the pH of plastic polymers

leads to chemical plastic deterioration causing changes of the

polymer microstructures. These acids are including nitrous acid,

nitric acid or sulfuric acid, citric, fumaric, gluconic, glutaric,

glyoxylic, oxalic, and oxaloacetic (32). The plastic surface

damages associated with metabolites and extracellular enzymes

released by bacteria (34).

Depolymerization of the plastic constituents is carried out by

depolymerase enzymes. The results of this reaction can be in the

form of oligomers, dimers, and monomers that are simpler than

polymers. They will be further processed according to the

presence of oxygen molecules in metabolism. Aerobic

degradation of those components will produce microbial

General Plastics Waste Management

Plastics waste landfill and incineration are two commonly

used plastic waste management methods. However, these two

methods are considered as the managing plastic waste processes

which have side effects on the environment as they release

various toxic gases into the air, besides landfill also requires a

large space. Plastics recycling activities are also relatively

ineffective in dealing with the abundance of plastic waste (13).

The application of reuse, reduce, and recycle is now widely

promoted in addition to solve plastic waste problems. It is

appropriate for postindustrial plastics, yet it is not effective for

plastics that have been used or consumed by people that are

usually mixed with other organic and inorganic wastes.

Afterward, chemical methods of plastics waste management

systems are influenced by several factors and conditions related

to the polymer constituents of each plastic (8).

biomass, CO

change those components into microbial biomass, CO

and CH or H S (35).

, and H

O. While anaerobic degradation will

, H O,

Extracellular and intracellular depolymerase enzymes

secreted by microbes have important roles in plastic waste

degradation. During the degradation process, the released

enzymes will break down complex polymers into smaller and

simpler chains. These decomposed small molecules will be

easily dissolved in water then absorbed through microbial

semipermeable cell membranes to be used as carbon and energy

sources. Assimilation occurs in microbial cytoplasms in which

the metabolic process occurs to produce energy, biomass, food

reserves, primary and secondary metabolites (29). After

degraded into smaller ones, plastic fragments such as monomers

will enter the cells. These components enter the microbial cell

metabolism system to undergo a subsequent degradation process

to form energy and biomass for microorganisms. Even though

monomers have formed, sometimes they do not fully

assimilated. They will be released outside of the cells and will

be used by other microorganisms that have a suitable

assimilation pathway for those monomers (32).

The next process of biodegradation is mineralization.

Mineralization is the final metabolic process of plastic waste

toxic compounds. This process changes those hazardous

compounds into more environmentally safe compounds (36).

Mineralization is a process of converting biodegradable

materials or biomass into gases, water, salt, minerals, and other

residues. The formed gases include carbon dioxide, methane,

and nitrogen components. The mineralization process will be

ended when all biodegradable compounds have been consumed

by microorganisms and all carbons are converted to carbon

dioxide (37, 38).

Plastics Biodegradation

A plastics waste processing effective method is needed (14,

5) to balance the increasing uses of plastics every year (26). It

is Biodegradation. Biodegradation is an effective, profitable, and

economically valuable plastics waste processing method. The

ability of many microorganisms to break down plastic polymers

is an advantage that can be used in dealing with problems arising

from the increasing accumulation of plastics waste every day.

Some microorganisms produce various kinds of enzymes, both

intracellular and extracellular, catalyze plastic polymers

degradation into safe smaller fragments (14, 15). The utilization

of microbial cells directly to degrade plastic C-C bonds is

considered more effective (27). Biodegradation is a specific

enzymatic process. Certain enzymes break down certain

substrates (28).

The plastic waste biodegradation process occurs through

several stages, including biodeterioration, depolymerization, and

assimilation. Biodeterioration is a cooperation between several

microbes and abiotic factors that breaks down polymers into

smaller ones. This process will be continued with

depolymerization. Depolymerization occurs in which microbes

secrete catalytic compounds in the form of enzymes and free

radicals to form biofilms helping them to break the polymer

chains progressively (29).

Biodeterioration is a process of changing or modifying

plastic polymers carried out by some microorganisms on the

plastic surface. The changes include chemical, physical, and

mechanical changes (30). This process will be accelerated by

biofilms formed by microorganisms on the plastic surface. A

biofilm is a form of living things community. Microbes attach

themselves and colonize the surface of an object to form

biofilms assisted by an extracellular compound produced by

them. In the form of biofilms, microbial cells attach one to

another in a polymer matrix containing polysaccharides and

proteins (13). Extracellular polymeric substances (EPS)

produced by microorganisms help them to break down the

plastic surface (31, 32). EPS consists of polysaccharides,

proteins, and nucleic acids (33).

Plastics Degrading Bacteria

Many plastics degrading bacteria have been widely reported

by researchers as compiled in table 1. Some of PE degrading

bacteria are including D.nigrificans and Pseudomonas

alcaligenes isolated from plastic waste contaminated soil

16), Enterobacter sp. D1 isolated from the guts of Galleria

(

mellonella (39) and P.putida MTCC 2475 isolated from garden

soil. P.putida MTCC 2475 reduced milk cover weight about

63.1

–

73.3% within

month incubation (40). In

the Enterobacter sp. D1 treated solution there was increasing of

alcohol, esters, acidic compounds, ethyl decanoate, and 6-

methyl-5-hepten-2-ol. Alcohol, alkaline, hydrocarbon, esters,

and acid compounds indicate bacterial metabolism in degrading

PE (41, 39). That process involves various oxidoreductase

enzymes (39).

EPS penetrates the plastic surface pores causing enlargement

of the pores. It is enhanced microbes, bacteria, to damage plastic

polymers, to form holes, and to encourage the physical

deterioration of plastic polymers (31, 32). Also, the formation of

biofilms on plastic surfaces encourages the formation of various

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2021, Volume 9, Issue 1, Pages: 148-157

Tabel 1: Plastics Degrading Bacteria

Observation of

Media

Plastic

Types

Incubation

References

Time

Bacteria

Isolate Sources

Garbage Soil

Degradation

32% of PWL

14% of PWL

Bacillus

Culture Broth Medium

Nutrient Broth

1 Month

(42)

(16)

amylolyticus

Bacillus subtilis

Desulfotomaculu

m nigrifans

Enterobacter sp.

Pseudomonas

alcaligenes

Pseudomonas

fluorescens

Pseudomonas

putida

Garbage Soil

Plastic Contaminated

Soil

Isolated from Gut of

Galleria mellonella

Plastic Contaminated

Soil

6.2% of PWL

1.98% of CD

1.98% of OI

A Carbon-Free Source

Agar Solid Medium

1 Days

(39)

(16)

(42)

6.2% of PWL

Nutrient Broth

1 Month

Garbage Soil

22% of PWL

18% of PWL

Culture Broth Medium

Pseudomonas

putida MTCC

Garden Soil

>10% of PWL

Mineral Salt Medium

1 Month

(40)

475

Streptomyces

SSP2

Streptomyces

SSP4

Sterptomyces

SSP14

Actinobacter

ursingii

Soil

8% of PWL

ATCC Medium

Solid MSM

1 Month

3 Days

(12)

(48)

Soil

11% of PWL

Soil

19% of PWL

Soil and Plastic Waste

Color Zone on the Medium

Alcanivorax

borkumensis

Marine Plastic Waste

Sedimentations

Liquid Medium Containing

0.05% Hexadecane

.5% of PWL

80 Days

(50)

Bacillus

carbonipphilus

25% of PWL

Mineral Broth

Mineral Agar

LDPE Contaminated

Soil

2 Months

(45)

(49)

34.55% of PWL

Bacillus

coagulans

Bacillus

licheniformis

KC2-MRL

Bacillus

LDPE Contaminated

Soil

16% of PWL

18.37% of PWL

Mineral Broth

Mineral Agar

Months

Soil

Plastic’s Surface Damage

Mineral Salt Medium

1 Month

2 Months

LDPE Contaminated

Soil

LDPE Contaminated

Soil

LDPE Contaminated

Soil

34.48% of PWL

21% of PWL

36.07% of PWL

14% of PWL

16.40% of PWL

8% of PWL

Mineral Agar

Mineral Broth

Mineral Agar

Mineral Broth

Mineral Agar

Mineral Broth

(45)

megaterium

Bacillus nedei

Bacillus smithii

Bacillus sp. KC3-

MRL

Bacillus

sporothermo-

durans

Soil

Plastic Surface Damage

36.54% of PWL

21% of PWL

Mineral Salt Medium

Mineral Agar

1 Month

(49)

(45)

LDPE

LDPE Contaminated

Soil

2 Months

Mineral Broth

Bacillus

weihenstephanens

Hydrocarbon enriched

soil

32.61% of TPBWL and

35.64% of ThPBWL

C-zopek-Dox Broth

6 Months

(82)

Burkholderia

cepacia

Hydrocarbon Enriched

Soil

31.43% of TPBWL and

36.34% of ThPBWL

C-zopek-Dox Broth

6 Months

(82)

Hydrocarbon Enriched

Soil

23.27% of TPBWL and

23.57% of ThPBWL

Escherichia coli

Pseudomonas

aeruginosa

Pseudomonas

fluorescens

Serratia sp. KCI-

MRL

Stenotropphomon

as sp. KC4-MRL

Streptomyces

coelicoflavus

Landfill Soil

Garbage Soil

Soil

18.75% of PWL

Mineral Salt Broth

45 Days

1 Month

4 weeks

(47)

(42)

(49)

(51)

22% of PWL

Culture Broth Medium

Mineral Salt Medium

Mineralt Salt Agar

Plastic Surface Damage

30% of PWL

Soil

Oil Contaminated Soil

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2021, Volume 9, Issue 1, Pages: 148-157

Plastic

Types

Observation of

Degradation

Incubation

References

Time

Bacteria

Isolate Sources

Media

NBRC 15399^T

Streptomyces

SSP2

Streptomyces

SSP4

Sterptomyces

SSP14

Ochrobacterum

anthropi

Soil

6% of PWL

9% of PWL

17% of PWL

20% of PWL

12% of PWL

11% of PWL

ATCC Medium

Mineral Salt Broth

Mineral Broth

1 Month

1 Bulan

1 Month

45 Days

40 Days

(12)

(47)

(53)

Soil

HDPE

Landfill Soil

Mangrove sediment

Bacillus cereus

Sporosacrina

globispora

Mineral Broth

0% of PWL in NB and

8.82% of PWL in BHB

Bacillus subtilis

Culture

NB and BHB

1 Month

(54)

Pseudomonas

auroginosa

5% of PWL in NB and

11% of PWL in BHB

Staphylococcus

aureus

4.76% of PWL in NB and

37.5% of PWL in BHB

Staphylococcus

pyogenes

8.33% of PWL in NB and

11.11% of PWL in BHB

4.59% of PWL in NB and

.75% of PWL in BHB

Bacillus subtilis

Culture

NB and BHB

1 Month

(54)

Staphylococcus

pyogenes

3.85% of PWL in NB and

3.92% of PWL in BHB

PET

Staphylococcus

aureus

8.75% of PWL in NB and

3.85% of PWL in BHB

Hydrolysis Zone Formed

on PHB Containing

Medium

Turbid Medium

Containing PHB as Carbon

Source

Streptomyces

lydicus MM10

Soil, Sand and

Wastewater

PHB

PLA

7 Days

(56)

Bacillus sp.

MKY2

Pseudomonas sp.

MKY1

Digester Sludge

Morphological Damage

PLA-Agar Plate

40 Days

(21)

PWL: Plastic’s Weight Loss; TPBWL: Thin Plastic Bag’s Weight Loss; ThPBWL: Thin Plastic Bag’s Weight Loss; CD: Carbon Decreasing; OI: Oxygene

Increasing; NB: Nutrient Broth; BHB: Bushnell Hash Broth.

Four polyethylene plastic degrading bacteria isolated from

soil were also reported by Patil (42). They were Bacillus

amylolyticus, B.subtilis, Pseudomonas putida, and Pseudomonas

fluorescens. These bacteria were separately incubated in a broth

medium containing polyethylene films and incubated for a

month. Based on the research, B.amylolyticus was able to reduce

were incubated in culture broth media for a month. Based on

that research, B.amylolyticus was able to reduce plastic samples

about

20%, B.firmus 12%, P.putida 30%, P.fluroscence 16%,

and B.subtilis 22%. FTIR analysis showed that the plastics were

damaged (44).

Bacillus spp. are potential LPDE degrading agents. By using

agar minerals incubated for two months, B.carbonipphilus was

able to degrade LDPE about 34.55%. Meanwhile,

B.sporothermo-durans degraded the sample about 36.54%,

B.sporothermodurans degraded it about 36.54%, B.coagulans

degraded the sample about 18.37%, B.neidei decreased the

plastic’s weiht about 36.07%, B.smithii degraded it about 16.0%,

and B.megaterium degraded it about 34.48%. In Mineral Broth

polyethylene

film

weight,

followed

by P.fluorescens with 22%, P.putida 18%, and B.subtilis 14%.

FTIR analysis stated that there was a rapid process of carbon

chain degradation through wave absorption. These bacteria

break down polythene polymers then serve them as their carbon

source (42). P.aeruginosa and P.stutzeri are also included as PE

degrading bacteria (15). Pseudomonas spp. have an inducible

operon system initiating the formation of certain enzymes that

are useful in unusual carbon sources metabolisms. Enzymes

produced by Pseudomonas spp. are including serine hydrolase,

esterase, and lipase (43).

media, B.carbonipphilus degraded

LDPE

about

25%, B.sporothermodurans 21%, B.coagulans 16%, B.neidei

14%, B.smithii 8%, and B.megaterium 21% (45).

microorganisms adhere to the plastic surfaces, they will start

trying to use those polymers as their carbon source (46).

The other LDPE degrading bacteria are Bacillus

When

The other 5 isolates of polyethylene degrading bacteria were

successfully isolated from dumped soil. The five bacteria

were Bacillus

amylolyticus, Bacillus

firmus, Pseudomonas

weihenstephanensis, Burkholderia cepacia, and Escherichia

coli. Within six months, B.weihenstephanensis was able to

putida, Pseudomonas fluroscence, and Bacillus subtilis. They

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2021, Volume 9, Issue 1, Pages: 148-157

reduce the weight of thick LDPE plastic bags around 32.61%

and thin plastic bags about 35.64%. B.cepacia can reduce the

weight of thick plastic bags about 31.43%, and 36.34% for thin

plastic bags. Whereas E.coli reduced 23.72% of thick plastic

bags weight and 23.57% for thin plastic bags (Mukherjee and

Chatterjee, 2014). LDPE weight reduction by Pseudomonas

depolymerase (56).

Enzymes Involved in Plastics Biodegradation

Many microbes produce various kinds of important enzymes

in plastic biodegradation. Enzymes such as laccase, lignin

peroxidase, manganese peroxidase, lipase, esterase, and amylase

are potential catalysts of plastic constituent polymers

degradation (59, 60). Lignin peroxidase, manganese peroxidase,

and laccase are the three main lignolytic enzymes (61, 62).

Lignolytic enzymes are including phenol oxidase or laccase,

heme peroxidase consisting of lignin peroxidase, manganese

peroxidase, and versatile peroxidase (63, 62).

There are two reactions involved in the polymer

biodegradation process, hydrolysis and oxidation. Hydrolysis is

the breaking down of polymers catalyzed by hydrolases

enzymes, while oxidation is a biodegradation process catalyzed

by various oxidoreductase enzymes. Hydrolase enzymes

catalyze the hydrolyzing reactions of esters, carbonates, amides,

and glycosidic bonds of various hydrolyzed polymers to produce

monomers. Meanwhile, oxidoreductase enzymes catalyze

oxidizing and reducing reactions of ethylene, carbonate, amide,

urethane, and others (59, 60).

The polymers hydrolysis process usually includes a reaction

involving three amino acid residues including aspartate,

histidine, and serine. Aspartate will interact with the histidine

ring to form hydrogen bonds. The histidine ring will interact

with serine. Histidine conducts the deprotonating process with

serine to form a nucleophilic alkoxide (-O), a group attacking

the ester bonds. This process results in an alcohol tip and an

acyl-enzyme complex. Then, water attacks the acyl-enzyme

complex to form a carboxyl-end and free enzyme that will be

further processed by microorganisms (64, 35). Bacillus sp.

BCBT21 is one of the hydrolases producing bacteria. It produces

lipase, CMCase, xylanase, chitinase, and protease that are

important in the degradation of plastic polymers (65).

When some polymer compounds can not be degraded by

certain enzymes, the other appropriate enzymes will work

together to break down those compounds. This phenomenon is

known as oxidation. For instance, monooxygenase and

dioxygenase will be coalesced to form a more fragmented

alcohol or peroxyl groups. The further reaction will be catalyzed

by peroxidase, breaking down these components into smaller

components. Peroxidases catalyze the reaction between a

peroxyl molecule and an electron acceptor such as phenol,

phenyl, amino, carboxyl, thiol, or unsaturated aliphatic

compound (64, 35).

aeruginosa was

18.75%

within

month

(47).

Moreover, P.fluorescens and Actinobacter ursingii are also

considered as LDPE degrading bacteria (48).

Furthermore, Jamil et al. (49), reported that Serratia sp.

KCI-MRL, Bacillus licheniformis KC2-MRL, Bacillus sp. KC3-

MRL, and Stenotrophomonas sp. KC4-MRL isolated from the

soil in Khasmir Smast, Pakistan, were able to damage the

surface of LDPE plastic films within one month of incubation.

Harshvardhan and Jha, cited from Jamil et al. (49) stated that

LDPE biodegradation through a series of enzymatic reactions

involving various enzymes that catalyze chemical changes of

plastic polymers such as oxidation, reduction, hydrolysis,

esterification, and molecular inner conversion.

Another

studi

also

reported

that Alcanivorax

borkumensis was able to form large biofilms on the surface of

LDPE waste. This bacterium is a species of hydrocarbon-

degrading bacteria which able to degrade LDPE (50). Based on

Golyshin et al., and Sabirova et al., the LDPE degradation

mechanism by this bacterium is carried out through several

enzymatic reactions involving various enzymes, such as alkane

hydroxylase (alkB1, alkB2), cytochrome P50, and Ferredoxin

(

50).

The ability of actinomycetes in degrading plastic waste was

also reported by some researchers. Some LDPE degrading

actinomycetes including Streptomyces coelicoflavus NBRC

5399T (51), Streptomyces SSP2, Streptomyces SSP4,

and

Streptomyces SSP14 are potential agents of plastic waste

biodegradation. They are also considered to be able to produce

bioemulsifier. Bioemulsifier is

a molecule produced by

microorganisms during the degradation of plastic polymers. The

microorganisms used in that study were able to produce

biosurfactants that are also important in plastics degradation

(

12). Actinomycetes produce various kind of metabolites which

play a vital role in plastics degradation (52).

One of the HDPE degrading bacteria is Ochrobacterum

anthropi. This bacterium degraded HDPE film by 20% in 45

days (47). PP degrading bacteria are including Bacillus

cereus and Sporosarcina globispora. The plastic degradation

ability

of B.cereus was

0.003

grams

per

day,

while S.globispora was 0.002 grams per day (53). Two PLA

degrading

and Bacillus sp.

bacteria

including Pseudomonas sp.

were reported by

MKY1

(21).

As the first step of PE degradation, carbonyl grub of the PE

is converted into alcohol. The process is catalyzed by the

monooxygenase enzyme. Then it will be converted into an

aldehyde catalyzed by alcohol dehydrogenase. Furthermore, the

formed aldehyde will be converted into fatty acids by the

aldehyde dehydrogenase. They will be entered into the β-

oxidation process for further processing inside microbial cells

MKY2

Meanwhile, B.subtilis, S.aureus, and S.pyogenes considered as

important PET and PS degrading bacteria (54). Ideonella

sakaiensis was also reported to degrade PET polymer (55, 19).

Another plastic degrading actinomycetes is Streptomyces

lydicus MM10. This filamentous bacterium produces Poly-

hydroxybutyrate (PHB) depolymerase, an enzyme that breaks

down PHB polymer (56). Furthermore, other PHB degrading

(

66, 38). Meanwhile, the oxidation process carried out by

laccase breaks down polyethylene polymers into carboxylic

acids. These formed acids will be entered fl-oxidation with

coenzyme-A. This reaction breaks the two carbon fragments of

the carboxylic acids to form acetyl-CoA. This result will be

included in the citric acid cycles for further metabolism. In the

end, water and carbon dioxide will be produced as the final

bacteria

are

Azotobacter and Bacillus (57).

Meanwhile,

Moritella sp.,

Shewanella sp., Psychrobacter sp.,

and Pseudomonas sp. play a role in PCL degradation (58).

Under the appropriate conditions and environments, various

kinds of bacteria can accumulate Poly-hydroxybutyrate (PHB) in

their cells then break down that polymer catalyzed by PHB

153

Journal of Environmental Treatment Techniques

2021, Volume 9, Issue 1, Pages: 148-157

products of PE biodegradation carried out by microorganisms

catalyzed by laccase (67).

microorganism's surface and the plastic film surface, the

polymeric bonds, and the level of plastic surface roughness.

Environmental factors also affect the biodegradation process,

including temperature and humidity (79, 80). Nutrition also has

important roles in the biodegradation (81).

PET degradation by Ideonella sakaiensis catalyzed by two

correlated types of enzymes, PETase (PET-digesting enzyme)

and MHETase (MHET-digesting enzyme). PETase converts

PET into mono (2-hydroxyethyl) terephthalic acid or MHET.

That process also produces secondary products such as

terephthalic acid (TPA) and bis (2-hydroxyethyl)-TPA.

Furthermore, the MHETase enzyme converts the formed MHET

into two monomers, TPA and ethylene glycol or EG (55, 68).

Polyurethane degraded by polyurethane degrading bacteria

such as Pseudomonas chlororaphis (69, 70). Two proteolytic

enzymes used in polyurethane polyester degradation are papain

and urease. Polymer degradation by papain is carried out by the

hydrolysis reaction of urethane and urea bonds. This hydrolysis

reaction produces free amines and hydroxyl groups (71, 62).

Meanwhile, aliphatic polyester such as PEA, PES, PPA, and

PBA can be degraded by hydrolase enzymes including lipase,

PEA depolymerase, and PHB depolymerase (72, 38). PHB

depolymerase is widely produced by some bacteria

including Alcaligenes faecalis, Rhodospirillum rubrum,

B.megaterium, A.beijerinckii and Pseudomonas lemoignei (73,

0 Conclusions

Biodegradation of plastic waste using plastics degrading

bacteria is a valuable plastic waste treatment that must be

implemented to maintain the environment quality of the

problems caused by plastic waste. This process has less even no

side effect that pollutes the environment. Plastic biodegradation

involves some hydrolase and oxidase enzymes produced by

many microbes including bacteria. This enzymatic process

breaks down the recalcitrant plastic polymers into microbial

biomass and other environmentally safe compounds throughout

several steps, including biodeterioration, depolymerization,

assimilation, and mineralization. Optimization of proper

environmental factors is the main factor to enhance the ability of

bacteria to degrade plastics waste.

Aknowledgment

We thank all the researchers for their valuable and important

studies about plastic waste biodegradation using plastic

degrading bacteria that cited by us in this review.

6).

PVA can be degraded by Pseudomonas spp. Those bacteria

secrete PVA degrading enzyme, polyvinyl alcohol

dehydrogenase (PVADH). PVA degradation occurs through two

stages. The first stage is the conversion of the 1,3-glycol

structure to β-ketone through random oxidative dehydrogenation

reactions or hydroxyl group oxidations to form a monoketone

structure. This process is catalyzed by alcohol oxidase. The

second step is breaking down the carbon-carbon bond and

changing the ketone groups to carboxylic (37, 38). Two possible

mechanisms occurred in this step. The first possibility is the

hydrolysis of the β-diketone structure of oxidized PVA

Ethical issue

Authors are aware of, and comply with, best practice in

publication ethics specifically with regard to authorship

(

avoidance of guest authorship), dual submission, manipulation

of figures, competing interests and compliance with policies on

research ethics. Authors adhere to publication requirements that

submitted work is original and has not been published elsewhere

in any language.

(

oxiPVA) catalyzed by β-diketone hydrolase (oxiPVA

hydrolase). The second possibility is the aldolase reaction

involving the monoketone structure of the oxidized PVA (74,

Competing interests

The authors declare that there is no conflict of interest that

would prejudice the impartiality of this scientific work.

8).

Another important plastic degradation catalyst is the PHA

hydrolase enzyme. It is classified as serine hydrolase that attacks

the branch chains and cyclic components of PHA (75, 62).

Meanwhile, PCL degradation can be carried out by

microorganisms by producing PCL enzymes hydrolases, lipases,

and esterases. PCL can be degraded by some microbes such

as Rhizopus arrhizuz (76, 38). PLA can be hydrolyzed by lipase,

proteinase K, and polyester polyurethane depolymerase (77, 38).

Moreover, nylon degradation involves the hydrolysis reaction of

amine bonds (-CONH-) of Nylon polymers that forms 12-amino

dodecanoic acid. This acid then oxidized to carboxyl and other

products. One of the nylons degrading bacteria is Geobacillus

thermocatenulatus (78, 38).

Authors’ contribution

All authors of this study have a complete contribution for

data collection, data analyses and manuscript writing.

References

Koushal V, Sharma R, Sharma M, Sharma R, Sharma V. Plastics:

Issues Challenges and Remediation. International Journal of Waste

Resources. 2014 Feb 10;4(1):1-6.

Kumari P, Murthy NS. A Novel Mathematical Approach for

Optimization of Plastic Degradation. International Journal of

Engineering Trends and Technology. 2013 August; 4(8):3539-42.

Kumar S, Das ML, Rebecca J, Sharmila S. Isolation and

identification of LDPE degrading fungi from municipal solid waste.

Journal of Chemical and Pharmaceutical Research. 2013 May;

Factors Affecting Biodegradation

Biodegradation is influenced by several factors including the

(3):78-81.

chemical structure of the polymers, the phase structure

amorphous or crystalline) of plastic polymers, molecular

UNEP. Single-Use Plastics: A Roadmap for Sustainability. 2018

June 5.

Jambeck R, Geyer R, Wilcox C, Siegler TR, Perryman M, Andrady

A, Narayan R, Law KL. Plastic waste inputs from land into the

ocean. Science. American Association for the Advancement of

Science. 2015 Feb 12;347(6223):768-71.

(

weight, miscibility of the polymer's constituent. Moreover, the

presence of hydrolyzed and oxidized compounds also affect the

biodegradation process carried out by microorganisms. Other

factors that also affect the rate of the biodegradation process are

hydrophobicity or hydrophilicity compatibility between the

154

Journal of Environmental Treatment Techniques

2021, Volume 9, Issue 1, Pages: 148-157

Geyer R, Jambeck JR, Law KL. Production, Use, and Fate of All

Plastics Ever Made. Science Advaces. 2017 Jul;3(7):1-5.

Arico Z, Jayanthi S. Pengolahan Limbah Plastik Menajdi Produk

Kreatif sebagai Peningkatan Ekonomi Masyarakat Pesisir. Martabe:

Jurnal Pengabdian Masyarakat. 2017 Nov 13;1(1): 1-6.

Drzyzga O, Prieto A. Plastic Waste Management, a Matter for the

Community. Microbial Biotechnology. 2018 Nov 8;12(1):66-8.

Mrowiec B. Plastic Pollutans in Water Environtment.

Environmental Protection and Natural Resources. 2017; 28(4): 51-5.

Sowmya H, Ramalingappa V, Krishnappa, Thippeswamy B. Low

Density Polyethylene Degrading Fungi Isolated from Local

Dumpsite of Shivamogga District. International Journal of

Biological Research. 2014 May 31;2(2): 39-43.

26 Pratomo H, Rohaeti E. Bioplastik Nata De Casava sebagai Bahan

Edible Film Ramah Lingkungan. Jurnal Penelitian Saintek. 2011

Oct;16(2):172-90.

27 Wei R, Zimmermann W. Microbial Enzymes for the Recycling of

Recalcitrant Petroleum-Based Plastics: How Far Are We?.

Microbial Biotechnology. 2017 Mar 28;10(6):1308-22.

28 Adamcová

Vaverková

Degradation

Biodegradable/Degradable Plastics in Municipal Solid-Waste

Landfill. Polish Journal of Environmental Studies. 2014 Jan;23(4):

1071-8.

29 Marjayandari L, Shovitri M. Potensi Bakteri Bacillus sp. dalam

Mendegradasi Plastik. Jurnal Sains dan Seni ITS. 2015;4(2):59-62.

30 Helbling C, Abanilla M, Lee L, Karbhari VM. Issues of variability

and durability under synergistic exposure conditions related to

advanced polymer composites in civil infrastructure. Composites

Part A: Applied Science and Manufacturing. 2006 Aug;37(8):1102–

10.

31 Bonhomme S, Cuer A, Delort AM, Lemaire J, Sancelme M, Scott

G. Environmental biodegradation of polyethylene. Polymer

Degradation and Stability. 2003 Jan;81(3): 441-52.

Kale SK, Deshmukh AG, Dudhare MS, Patil VB. Microbial

Degradation of Plastic:

a Review. Journal of Biochemical

Technology. 2015 Dec 25;6(2): 952-61.

Soud SA. Biodegradation of Polyethylene LDPE Plastic Waste

using Locally Isolated Streptomyces sp. Journal of Pharmacetical

Sciences and Research.. 2019;11(4):1333-9.

Kumar VR, Kanna GR, Elumalai S. Biodegradation of Polyethylene

Bioremediation&Biodegradation. OMICS Publishing Group.

017;8(1):1-8.

Okmoto K, Izawa M, Yanase H. Isolation and Application of a

Styrene-Degrading Strain of Pseudomonas putida to Biofiltration.

Journal of Bioscience and Bioengineering. Elsevier. 2003

Jan;95(6):633-6.

Green

Photosynthetic

Microalgae.

Journal

32 Sharma B, Rawat H, Pooja, Sharma R. Bioremediation-A

Progressive Approach toward Reducing Plastic Wastes.

International Journal of Current Microbiology adn Applied Science.

2017 Dec 10;6(12):1116-31.

33 Gilan 1, Sivan A. Extracellular DNA Plays an Important Structural

Role in the Biofilm of the Plastic Degrading Actinomycete

Rhodococcus ruber. Advances in Microbiology. 2013;3(03):543-51.

34 Rosario LLD, Baburaj S. Isolation and Screening of Plastic

Degrading Bacteria from Polythene Dumped Garbage Soil.

Agrawal P, Singh RK. Breaking Down of Polyethylene by

Pseudomonas

Species.

International

Journal

Scientific&Engineering Research. 2016 March;7(3):124-7.

International Journal for Research in Applied Science

Engineering Technology. 2017;5(12):1028-32.

35 Tiwari AK, Gautam M and Maurya HK. Recent Development of

Biodegradation Techniques of Polymer. International Journal of

Research-GRANTHAALAYAH. 2018 Jun 30;6(6): 414-52.

Begum MA, Varalakshmi B, Umamagheswari K. Biodegradation of

Polythene Bag using Bacteria Isolated from Soil. International

Journal of Current Microbiology and Applied Sciences. 2015; 4(11):

74-80.

Proshad R, Islam MS, Kormoker T, Haque MA, Rahman MM,

Mithu MMR. Toxict Effect of Plastic on Human Health and

36 Alshehrei F. Biodegradation of Low Density Polyethylene by Fungi

Isolated from Red Sea Water. International Journal of Current

Microbiology and Applied Sciences. 2017 Aug 10;6(8):1703-9.

37 Kyrikou J, Briassoulis D. Biodegradation of Agricultural Plastic

Environment:

a Sequences of Health Risk Assessment in

Bangladesh. International Journal of Health. 2018;6(1):1-5.

Alabi OA, Ologbonjaye KI, Awosolu O, Alade OE. Public and

Films: A Critical Review. Journal of Polymers and the

Environmental Health Effects of Plastic Wastes Disposal:

Review. Journal of Toxicology and Risk Assessment. 2019 Apr 5;

(2):1-13.

Oberbeckmann S, Labrenz M. Marine Microbial Assemblages on

Microplastics: Diversity, Adaptation, and Role in Degradation.

Annual Review of Marine Science. 2020 Jan 3;12(1):209-32.

Weng Y-X, Jin Y-J, Meng Q-Y, Wang L, Zhang M, Wang Y-Z.

Biodegradation behavior of poly (butylene adipate-coterephthalate)

Environment. 2007 Aug 1;15(3).

38 Leja K, Lewandowicz G. Polymer Biodegradation and

Biodergadable Polymers-a Review. Polish Journal of Environmental

Studies. 2010;19(2):255-66.

39 Ren L, Men L, Zhang Z, Guan F, Tian J, Wang B, Wang J, Zhang

Y, Zhang W. Biodegradation of Polyethylene by Enterobacter sp.

D1 from the Guts of Wax Moth Galleria Mellonella. International

Journal of Environtmental Research and Public Health. 2019 May

31;16(11):1-11.

(PBAT), poly (lactic acid) (PLA), and their blend under soil

conditions. Polymer Testing. 2013 Aug;32(5): 918-26.

40 Saminathan P, Sripriya A, Nalini K, Sivakumar T, Thangapandian

V. Biodegradation of Plastics by Pseudomonas putida isolated from

Garden Soil Samples. Journal of Advanced Botany and Zoology.

2014 May 1;1(3):1-4.

41 Shahnawaz M, Sangale MK, Ade AB. Bacteria-based polythene

degradation products: GC-MS analysis and toxicity testing.

Environmental Science and Pollution ResearchEnviron. 2016 Feb

18;23(11); 10733–41.

42 Patil RC. Screening and Characterization of Plastic Degrading

Bacteria from Garbage Soil. British Journal of Environmental

Sciences. 2018;6(4):33-40.

43 Sriningsih A, Shovitri M. Potensi Isolat Bakteri Pseudomonas

sebagai Pendegredasi Plastik. Jurnal Sains dan Seni ITS. 2015;4(2):

67-70.

Kim MY, Kim C, Moon J, Heo J, Jung SP, Kim JR. Polymer Film-

Based Screening and Isolation of Polylactic Acid (PLA)-Degrading

Microorganisms. Journal of Microbiol and Biotechnol. Korean

Society for Microbiology and Biotechnology. 2017 Feb 28;27(2):

42-9.

Purwaningrum, P. Upaya Mengurangi Timbulan Sampah Plastik di

Lingkungan. Indonesian Journal of Urban and Environmental

Technology. 2016 Dec 6;8(2):141-7.

Hamlet C, Matte T, Mehta S. Combating Plastic Air Polution on

Earth’s Day. Vital Strategies Environmental Division. 2018.

Chandegara VK, Cholera SP, Nandasana JN, Kumpavat MT, Patel

KC. Plastic Packaging Waste Impact on Climate Change and its

Mitigation. In: Subbaiah R, Prajapati GV, Water management and

climate smart agriculture. Adaptation of Climatic Resilient Water

Management and Agriculture, Gyan Publishing House, New Delhi,

India, 2015; 3: 404-15.

44 Jumaah, O. S. Screening of Plastic Degrading Bacteria from

Dumped Soil Area. Journal of Environmental Sinece, Toxicology

and Food Technology. 2017 May;11(5): 93-8.

Halden RU. Plastics and Health Risk. Annual Review of Public

Health. 2010 Apr 21;31:179-94.

45 Shresta JK, Joshi DR, Regmi P, Badahit G. Isolation and

Identification of Low Density Polyethylene (LDPE) Degrading

155

Journal of Environmental Treatment Techniques

2021, Volume 9, Issue 1, Pages: 148-157

Bacillus spp. from

Microbiology. 2019 Mar 5;2(4):30-4.

Soil of Landfill Site. Acta Scientific

63 Dashtban M, Schraft H, Syed TA, Qin W. Fungal Biodegradation

and Enzymatic Modification of Lignin. International Journal of

Biochemistry and Molecular Biology. 2010 May 23;1(1):36-50.

64 Lucas N, Bienaime C, Belloy C, Queneudec M, Silvestre F, Nava-

Saucedo J-E. Polymer biodegradation: Mechanisms and estimation

Deepika S, Madhuri JR. Biodegradation of Low Density

Polyethylene by Microorganisms from Garbage Soil. Journal of

Experimental Biology and Agricultural Science. 2015;3(1):15-21.

Riandi MI, Kawuri R, Sudirga SK. Potential of Pseudomonas sp.

and Ochrobacterum sp. Isolated from Various Soil Sample as

Degrading Bacteria of High Density Polyethylene (HDPE) and Low

Density Polyethylene (LDPE) Plastic. SIMBIOSIS Journal of

Biological Science. 2017 Sep 30;5(2):58-63.

Hussein AA, Al-Mayaly IK, Khudeir SH. Isolation, Screening and

Identification of Low Density Polyethylene (LDPE) Degrading

Bacteria from Contaminated Soil With Plastic Wastes. Mesopotamia

Environmental Journal. 2015;1(4):1-14.

techniques – A review. Chemosphere. Elsevier BV. 2008

Sep;73(4):429–42.

65 Dang TCH, Nguyen DT, Thai H, Nguyen TC, Tran TTH, Le VH,

Nguyen VH, Tran XB, Pham TPT, Nguyen TG, Nguyen QT. Plastic

Degradation by Thermophilic Bacillus sp. BCBT21 Isolated from

Composting Agricultural Residual in Vietnam. Advances in Natural

Sciences: Nanoscience and Nanotechnology. 2018 Mar 29;9(1):1-

11.

66 Gautam R, Bassi AS, Yanful EK. A Review of Biodegradation of

Synthetic Plastic and Foams. Applied Biochemistry and

Biotechnology. 2007 Apr;141(1):85–108.

67 Khalil MI, Ramadan NA, Albarhawi RK. Biodegradation of

Polymers by Fungi Isolated from Plastic Garbage and the Optimum

Condition Assessment of Growth. J. Raff. Env. 2013 May;1(1):33-

43.

68 Austin HP, Allen MD, Donohoe BS, Rorrer NA, Kearns FK,

Silveira RL, Pollard BC, Dominick G, Duman R, Omari KE,

Mykhaylyk V, Wagner A, Michener WE, Amore A, Skaf MS,

Crowley MF, Thorne AW, Johnson CW, Woodcock HL, McGeehan

JE, Beckham GT. Characterization and Engineering of a Plastic-

degrading Aromatic Polyesterase. Proceedings of the National

Academy of Sciences. 2018 Apr 17;115(19):4350–7.

Jamil SUU, Zada S, Khan I, Sajjad W, Rafiq M, Shah AA, Hasan F.

Biodegradation of Polyethylene by Bacterial Strains Isolated from

Kashmir Cave, Buner, Pakistan. Journal of Cave and Karst Studies.

017;79(1): 73-80.

Delacuvellerie A, Cyriaque V, Gobert S, Benali S, Wattiez R. The

Plastisphere in Marine Ecosystem Hosts Potential Specific

Microbial Degraders Including Alcanivorax borkumensis as a Key

Player for the Low Density Polyethylene Degradation. Journal of

Hazardous Materials. 2019 Dec;380:1-11.

Duddu MK, Tripura KL, Gantuku G, Divya DS. Biodegradation of

Low Density Polyethylene (LDPE) by

Producing Thermophilic Streptomyces coelicoflavus NBRC 15399 .

African Journal of Biotechnology. 2015;14(4):327-40.

a New Biosurfactant-

Waithaka PN, Gathuru EM, Githaiga BM, Ochieng EO, Laban LT.

Microbial Degradation of Polythene using Actinomycetes Isolated

from maize Rhizosphere, Forest and Waste Damping Sites Within

Egerton University, Kenya. International Journal on Emerging

Technologies. 2017;8(1):05-10.

69 Howard GT, Ruiz C, Hillard NP. Growth of Pseudomonas

chlororaphis on a polyester-polyurethane and the purification and

characterization of a polyurethane-esterase enzyme. International

Biodeterioration & Biodegradation.1999 Mar;43(1-2):7-12.

70 Caruso G. Plastic Degrading Microorganisms as

a Tool for

Helen AS, Uche EC, Hamid FS. Screening of Polyptopylene

Degdradation Potential of Bacteria Isolated from Mangrove

Ecosystems in Peninsular Malaysia. International Journal of

Bioscience, Biochemistry and Bioinformatics. 2017;7(4): 245-251.

Asmita K, Shubhamsingh T, Tejashree S. Isolation of PlASTIC

Degrading Microorganisms from Soil Samples Collected at Various

Locations in Mumbai, India. International Research of

Environetmental Sciences. 2015;4(3):77-85.

Yoshida S, Hiraga K, Takehana T, Taniguchi I, Yamaji H, Maeda J,

Toyohara K, Miyamoto K, Kimura Y, Oda K. A bacterium that

degrades and assimilates poly(ethylene terephthalate). Science. 2016

Mar 11;351(6278):1196–99.

Bioremediation of Plastic Contamination in Aquatic Environments.

Journal of Pollution Effects&Control. 2015;3(3): 1-2.

71 Phua SK, Castillo E, Anderson JM, Hiltner A. Biodegradation of a

Polyurethane in vitro. Journal of Biomedical Materials Research.

1987 Feb;21(2): 231-46.

72 Kim DY, Rhee YH. Biodegradation of Microbial and Synthetic

Polyesters by Fungi. Applied Microbiology and Biotechnology.

2003 Jan 25;61(4):300-8.

73 Panagiotidou E, Konidaris C, Baklavaridis A, Zuburtikudis 1,

Achilias D, Mitlianga P. A simple route for purifying extracellular

poly3- hydroxybutyrate- depolymerase from

Penicillium

pinophilum. Enzyme Research. 2014 Sep 23; 2014:1-6.

Aly MM, Tork S, Qari HA, Al-Seeni MN. Poly-β-hydroxy butyrate

Depolymerase from Streptomyces lydicus MM10, Isolated from

Wastewater Sample. International Journal of Agriculture & Biology.

74 Kawai F, Hu X. Biochemistry of microbial polyvinyl alcohol

degradation. Applied Microbiology and Biotechnology. 2009 Jul

10;84(2):227-37.

015 Sep1;17(5):891-900.

75 Tokiwa Y, Calabia BP, Ugwu CU, Aiba S. Biodegradability of

Plastics. International Journal of Molecular Sciences. 2009 Aug

26;10(9):3722-42.

76 Tokiwa Y, Suzuki T. Hydrolysis of polyesters by lipases. Nature.

Springer Science and Business Media LLC. 1977 Nov;270:76-8.

77 Kim JM, Jeon CO. Isolation and Characterization of a New

Benzene, Toluene, and Ethylbenzene Degrading Bacterium,

Acinetobacter sp. B113. Current Microbiology. 2008 Oct

7;58(1):70-5.

78 Tomita K, Ikeda N, Ueno A. Isolation and characterization of a

thermophilic bacterium, Geobacillus thermocatenulatus, degrading

nylon 12 and nylon 66. Biotechnology Letter. 2004; 25:1743-6.

79 Bikiaris DN. Nanocomposites of aliphatic polyesters: An overview

of the effect of different nanofillers on enzymatic hydrolysis and

biodegradation of polyesters. Polymer Degradation and Stability.

2013 Sep;98(9):1908-28.

80 Râpă M, Popa ME, Cornea PC, Popa VL, Grosu E, Geicu-Cristea

M, Stoica P, Tanase EE. Degradation Study by Trichoderma spp. of

poly (3-hydroxybuthyrate) and Wood Fibers Composites. Romanian

Biotechnological Letters. 2014;19(3): 9390-9.

Aburas MMA. Degradation of Poly (3-hydroxybuthyrate) using

Aspergillus oryzae obtained from Uncultivated Soil. Life Science

Journal. 2016;13(3):51-6.

Sekiguchi T, Sato T, Enoki M, Kanehiro H, Uematsu K, Kato C.

Isolation and Characterization of Biodegradable Plastic Degrading

Bacteria from Deep-Sea Environments. JAMSTEC Report of

Research and Development. 2011;11:33-41.

Matsumura S. Mechanism of biodegradation. Biodegradable

polymers for industrial applications. El Sevier. 2005; 357-410.

Ganesh P, Dineshraj D, Yoganathan K. Production and Screening of

Depolymerasing Enzymes by Potential Bacteria and Fungi Isolated

from Plastic Waste Dump Yard Sites. International Journal of

Applied Research. 2017;3(3):693-695.

Hofrichter M, Lundell T, Hatakka A. Conversion of Milled Pine

Wood by Manganese Peroxidase from Phlebia radiata. Applied and

Environmental Microbiology. 2001 Oct 1;67(10):4588-93.

Bhardwaj H, Gupta R, Tiwari A. Microbial Population Associated

with Plastic Degradation. Open Acces Scientific Reports. 2012;

(5):1-4.

156