Bioprospection of Indigenous Molds Obtained from Diospyros javanica Leaves as Agents of Plastic Biodegradation

Abstract

Plastic is a material that is difficult to decompose because it has long polymer chains, high molecular weight, and hydrophobic properties. Plastic degradation is often carried out chemically, but this results in various environmental problems such as the release of toxic by-products and pollutants. The environmentally friendly solution to reduce plastic is by natural decomposition with the help of microorganisms which is known as biodegradation. This research provides an appropriate solution to the problem of plastic degradation by utilizing indigenous mold obtained from the Diospyros javanica tree. Biodegradation tests were carried out to determine the ability of plastic degradation by these indigenous molds which are assumed to be efficient in an environmentally-friendly plastic degradation. Indigenous molds were identified and assumed to be three types of mold isolates of the genera Humicola, species Aspergillus flavus, and Aspergillus niger. Biodegradation analysis was carried out using Fourier Transform Infrared (FTIR) analysis in order to detect changes in functional groups (chemical compounds and bonds) and Scanning Electron Microscope (SEM) analysis to help visualize the plastic surface of the test results. The results show that the genera Humicola, Aspergillus flavus, and Aspergillus niger have potential for plastic biodegradation. The DJ1 isolate (Humicola genus) had the largest percentage of plastic degradation efficiency, namely 23.96 % after 15 days of incubation. The results within this research suggests that Humicola shows a great potential to fill in a role in plastic biodegradation.