Crystallized polylactic acid (CPLA) is a prevalent bioplastic which, despite being biodegradable, is extremely resistant to decomposition in natural environments. As a result, CPLA waste contamination is rapidly becoming a prevalent issue. Lentinula edodes and Flammulina velutipes are two widespread white-rot fungi whose capabilities for bioplastic degradation have not been examined. This study aimed to determine a natural approach for reducing plastic waste by evaluating the ability of L. edodes and F. velutipes to degrade CPLA bioplastic. It was hypothesized that CPLA samples would decrease in mass when individually treated with L. edodes and F. velutipes due to their similarities to previously-examined fungi such as C. versicolor and P. chrysosporium1,2. To assess this hypothesis, 180 discs 6 mm in diameter were cut from Simple Truth™ CPLA knives and submerged in potato dextrose broth (PDB), L. edodes liquid culture, and F. velutipes liquid culture for 23 days. The initial and final masses were used to calculate the percent change in mass. The results showed that the group treated with L. edodes experienced the greatest decrease in mass at 0.2134%, followed by the control group at 0.3514%, and the F. velutipes group at 0.0537%. An ANOVA test showed that the p-value of 0.3234 was greater than the alpha value of 0.05. Hence, the results were not significant and the hypothesis was not supported. Therefore, bioplastic waste accumulation, particularly CPLA waste, remains a prevalent issue as the material is predominantly unaltered by fungal biodegradation.
"The Effect of Exposure to Lentinula edodes and Flammulina velutipes on the Biodegradation of Crystallized Polylactic Acid,"
Journal of the South Carolina Academy of Science: Vol. 21:
3, Article 9.
Available at: https://scholarcommons.sc.edu/jscas/vol21/iss3/9