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Explora: Environment
and Resource Enzymatic degradation

Figure 1. Weight loss (%) of low-density polyethylene as a function of
enzyme concentration for all systems (lipase [Lip], laccase [Lac], and Figure 3. Weight loss (%) of low-density polyethylene as a function of
Lip-Lac) enzyme concentration for the lipase-laccase enzyme system

Figure 4. Weight loss (%) of low-density polyethylene as a function of
Figure 2. Weight loss (%) of low-density polyethylene as a function of enzyme concentration for the laccase enzyme system
enzyme concentration for the lipase enzyme system
available for enzymatic action, leading to more efficient
applications. Therefore, achieving higher weight loss is degradation. The influence of incubation time is most
desirable for effective waste management. The Lip-Lac pronounced in the 0.5 cm particle size across all enzyme
system exhibited the most significant weight loss (Figure 3). systems, particularly in the Lip-Lac system. Weight loss
At 100% concentration, the weight loss reaches 15.21%, percentages increased significantly from day 10 to day 30,
indicating a high degradation rate. This suggests that the indicating that longer exposure enhances degradation. If
combined action of Lip and Lac enzymes synergistically the incubation period were extended to 60 days, it would
enhanced LDPE degradation. be reasonable to anticipate further degradation, potentially

3.2. Effect of LDPE particle size on LDPE degradation leading to higher weight loss percentages, assuming
enzyme activity remains stable over time. Notably, no
Harrat et al. previously reported weight loss of 7.6% and formal enzyme activity assay was conducted before the
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5.53% using Candida tropicalis SLNEA04 and Rhodotorula degradation experiments. This assumption is supported by
mucilaginosa SLNEA05, respectively. Their findings are DSouza et al., who reported a peak weight loss of 26.15%
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consistent with our results for the Lip system on day 10 after 55 days of incubation. Similarly, Awasthi et al.
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for 0.5–1 cm LDPE samples. Table 2 presents the initial conducted experiments over a comparable timeframe
and final weights of LDPE samples with varying particle (10–30 days) using Rhizopus oryzae, a fungus known to
sizes after enzymatic treatment. The data indicate that
smaller particles (0.5 cm) experienced greater weight loss secrete Lip.
compared to larger ones (1.5 and 2.0 cm). This suggests According to Table 2 and Figures 5-8, the smallest
that reducing particle size enhances the surface area particle size of 0.5 cm consistently resulted in the highest

Volume 2 Issue 3 (2025) 5 doi: 10.36922/EER025220042