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Explora: Environment
and Resource Enzymatic degradation

from a total of over 450 million tons produced annually then further metabolize these units into end products,
worldwide. 11,12 This increase in production is mainly due such as CO , H O, CH , and N . Ehrhardt and Rothenberg
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2
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to the manufacturing of single-use disposable plastics, noted that green hydrogen is also a realizable outcome.
which make up around 50% of all plastic products. The The by-products of microbial plastic degradation offer
significant increase in plastic waste disposal, which significant potential for addressing plastic pollution by
consists of materials that do not easily break down repurposing these products in other applications, thereby
and thus remain in the environment, has resulted in creating a recycling loop for these harmful materials
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land and ocean pollution. 14,15 Due to their practical that are otherwise difficult to eliminate and contribute
physicochemical qualities (e.g., crystallinity, molecular to environmental pollution. Municipal and public waste
weight, hydrophobicity, and additive composition), some management is currently the biggest environmental issue
polymers, such as low-density PE (LDPE), are utilized in a affecting emerging countries, especially Nigeria, 36-39 where
variety of applications. At present, PE is derived from thin some cities are stench-filled with tons of uncontrollable
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polyolefin plastic sheets and films utilized in the packaging solid and plastic waste. 40-44 As a result of Nigeria’s current
of products. Furthermore, plastic bags constitute 60% of economic state, LDPE sachets are commonly used for
the total plastic production, which includes LDPE, and are packaging water, popularly known as “pure water.” These
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considered the most common form of solid waste. LDPE pure water sachets (PWS) represent the most affordable
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is characterized by good strength, chemical resistance, packaging option. While the use of LDPE has gained
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flexibility, and transparency. Its hydrophobic nature widespread acceptance across various communities, it has
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prevents microorganisms from accessing it. The resistance unfortunately resulted in the rise of a solid waste stream, as
of LDPE to microbial degradation is largely due to its high LDPE degrades at an extremely slow rate.
molecular weight, which limits enzyme accessibility, and This study was initiated to investigate how Lip and
the absence of functional groups, which prevents effective laccase (Lac) enzymes impact the degradation rate of
microbial attachment or breakdown. In addition, its low LDPE wastes (specifically PWS). While several studies
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surface energy further hinders microbial colonization have explored LDPE degradation using microbial enzymes,
by reducing surface wettability and interaction with most have focused on either enzyme concentration or
enzymes. LDPE is characteristically inert, and its rate polymer structure in isolation. For instance, Liu et al.
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of degradation is extremely slow, taking several decades, examined LDPE degradation using Yarrowia lipolytica,
which causes it to remain in nature for an extended period. but without optimizing for both enzyme load and particle
Due to its complicated 3D structure and large molecular size simultaneously. Mazaheri and Nazeri reported the
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weight, it is recalcitrant to degradation. Despite being effectiveness of Stenotrophomonas spp. and Alcaligenaceae
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widely used for managing LDPE waste, incineration and in degrading LDPE, demonstrating microbial potential,
landfilling methods are linked to several environmental though their work did not incorporate enzymatic
drawbacks. Thus, biodegradation has been demonstrated concentration gradients or particle size variations as
to be the optimal choice for managing plastic waste. 22 interactive variables. Khandare et al. used marine
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Since it is virtually impossible to eliminate their bacteria for LDPE biodegradation and highlighted
manufacture, there is growing interest in developing more particle preparation and treatment time, but lacked an
effective and rapid methods for reducing the accumulation integrative assessment of enzyme-specific parameters,
of these widely used yet environmentally harmful plastic such as those studied with Aspergillus flavus enzymes in
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items. 23,24 It is highly likely that scientists, who are constantly this research. DSouza et al. worked with an Aspergillus
engaged in researching and developing biologically safe consortium to degrade LDPE under controlled conditions,
methods, will identify a solution to address the rapid yet did not combine enzyme concentration and plastic
accumulation of plastic waste. Researchers have identified size optimization, a gap this study aims to bridge using a
particular microorganisms that can generate enzymes bifunctional Lip-Lac system. The novelty of the study is
capable of decomposing these polymers. 25-28 Enzymes that that it is the first to simultaneously optimize both enzyme
degrade the carbon backbone of polymers are classified concentration and plastic particle size to maximize
under the hydrolase family, including esterases, lipases LDPE degradation using enzymes from A. flavus. The
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(Lips), depolymerases, and PETases. Buchholz et al. study supports Sustainable Development Goal (SDG) 12
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enumerated and discussed enzymes that require water (Responsible Consumption and Production) and SDG
to function. These enzymes can break down the plastic 13 (Climate Action). By utilizing microbial enzymes
polymer into simpler monomeric units that are easily from A. flavus (a naturally occurring fungus) for the
decomposable within the environment and can serve as a degradation of LDPE plastic waste, our study promotes
carbon source for microorganisms. The microorganisms the development of green technologies aligned with the
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Volume 2 Issue 3 (2025) 2 doi: 10.36922/EER025220042