Potential of fungi isolated from the dumping sites mangrove rhizosphere soil to degrade polythene

Manisha K Sangale,Avinash B Ade,Mohd Shahnawaz

doi:10.1038/s41598-019-41448-y

Abstract

Polythene is the most widely used plastic around the globe. Among the total plastic waste generated, polythene contributes the maximum share (64%). Various strategies/methods are being utilized to deal with the increasing rate of plastic waste, but among all the methods, bioremediation is regarded as the ecofriendly and widely accepted method. In the current investigation, we have attempted to discover the elite polythene deteriorating fungi (isolated from the rhizosphere soil of Avicennia marina). From 12 different eco-geographical locations along the West Coast of India, total 109 fungal isolates were recorded. The polythene deteriorating fungi were screened at varied pH (3.5, 7 and 9.5) based on changes in weight and tensile strength of the treated polythene at ambient temperature with continuous shaking for 60 days. BAYF5 isolate (pH 7) results in maximum reduction in weight (58.51 ± 8.14) whereas PNPF15 (pH 3.5) recorded highest reduction in tensile strength (94.44 ± 2.40). Surprisingly, we have also reported weight gain, with highest percent weight gain (28.41 ± 6.99) with MANGF13 at pH 9.5. To test the reproducibility of the results, the elite polythene degrading fungal isolates based on weight loss and reduction in tensile strength were only used for repetition experiment and the results based on the reduction in tensile strength were found only reproducible. Polythene biodegradation was further confirmed using Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The most efficient polythene deteriorating fungal isolates were identified as Aspergillus terreus strain MANGF1/WL and Aspergillus sydowii strain PNPF15/TS using both morphological keys and molecular tools.

Highlights

The word plastic is originated from the root word ‘plastikos’ (‘grow’ or ‘form’: able to be molded into different shapes) of the Greek language[1]
Maximum (31) fungal isolates were recorded from Mangalore locality whereas minimum (4) fungal isolates were reported in Surat, Mirya Bandar and Pudponnani
Chatterjee et al.[78] reported the formation of C-H stress group at peak 2915 and we reported similar peak at 2912.10 cm−1 in abiotic treated PE and documented the reduction in the peak with both the fungal strains (A. terreus strain MANGF1/WL and A. sydowii strain PNPF15/tensile strength (TS)) to 2912.09 cm−1 and 2912.92 cm−1 respectively

Summary

Introduction

The word plastic is originated from the root word ‘plastikos’ (‘grow’ or ‘form’: able to be molded into different shapes) of the Greek language[1]. Terrestrial animals usually consume discarded plastic bags along with foodstuff and experiences severe health issues, which lead to www.nature.com/scientificreports/ Their death[12,19]. The lack of provision for the proper disposal of post-consumer plastic wastes, results in littering on road which often chokes open drainage systems, and leads to flood like condition during rainy seasons At dumping sites, it mixes with the soil and release of the toxic compounds makes fertile land, infertile. In the current investigation, efforts were made to select those plastic waste dumping sites with growing mangroves surrounded by marine water along the West Coast of India for collection of the rhizosphere soil of Avicennia marina (Forsk.) Vierh., to isolate, screen, and characterize the potential polythene degrading fungi

Methods

Results

Discussion

Conclusion