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Explora: Environment
and Resource Enzymatic degradation

Table 2. Percentage weight loss of enzyme‑treated LDPE
samples with varying particle sizes
Enzyme Sample Initial Final weight Weight loss
size (cm) weight (g) (g) (%)
Day Day Day Day
10 30 10 30
Lipase 0.5 0.0015 0.0014 0.0012 6.67 20.00
1.0 0.0036 0.0034 0.0032 5.56 11.11
2.0 0.0117 0.0116 0.0114 0.85 2.56
Lip-Lac 0.5 0.0021 0.0019 0.0016 9.52 23.81
1.0 0.0046 0.0043 0.0039 6.52 15.21
2.0 0.0111 0.0108 0.0104 2.70 6.31
Laccase 0.5 0.0016 0.0016 0.0014 0.00 12.5
1.0 0.0038 0.0037 0.0035 2.63 7.89
2.0 0.0105 0.0105 0.0103 0.00 1.90
Abbreviations: Lac: Laccase; LDPE: Low-density polyethylene; Figure 6. Relationship between low-density polyethylene weight loss (%)
Lip: Lipase. and particle size for the lipase enzyme system

Figure 5. Relationship between low-density polyethylene weight loss (%)
and particle size for all enzyme systems (lipase [Lip], laccase [Lac], and Figure 7. Relationship between low-density polyethylene weight loss (%)
Lip-Lac). and particle size for the lipase-laccase enzyme system

percentage weight loss across all enzyme systems. However, Reducing the particle size below 0.5 cm could potentially
on day 10, 0% weight loss was recorded for particle sizes of increase degradation rates due to a greater surface area.
0.5 and 2 cm in the Lac system, despite Lac being among However, practical limitations, such as handling difficulties
the main fungal enzymes involved in PE biodegradation. and potential agglomeration, may arise. Conversely,
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Smaller particle sizes provide a larger surface area-to-volume increasing the particle size beyond 2 cm would likely
ratio, facilitating better enzyme-substrate interactions. This decrease degradation efficiency, as the reduced surface area
principle is well-established in biodegradation studies, where would limit enzyme access to the polymer chains. Optimal
increased surface area enhances microbial and enzymatic LDPE biodegradation is achieved by combining smaller
activity, thereby resulting in higher degradation rates. particle sizes (0.5 cm) with higher enzyme concentrations
During LDPE degradation, several physical and mechanical (100%). Such a combination maximizes the surface area
properties have been reported to decline, including tensile for enzyme interaction and ensures sufficient enzymatic
strength, tear strength, elongation at break, Young’s activity to effectively break down the polymer chains. The
Modulus, stiffness, hardness, and weight by 10.15%. 63 Lip-Lac system demonstrates the most favorable results,

Volume 2 Issue 3 (2025) 6 doi: 10.36922/EER025220042