Utilization of Noxious Weed Water Hyacinth Biomass as a Potential Feedstock for Biopolymers Production: A Novel Approach

Rijuta Ganesh Saratale,Dong-Su Kim,Gajanan S Ghodake,Yooheon Park,Ram Naresh Bharagava,Han-Seung Shin,Ganesh Dattatraya Saratale,Hee-Seok Lee,Si-Kyung Cho

doi:10.3390/polym12081704

Abstract

This study aims to utilize a noxious weed water hyacinth biomass (WH) for polyhydroxybutyrate (PHB) production. Alkaline and peracetic acid pretreatment was employed for the hydrolysis of WH and consequently enzymatic saccharification to produce fermentable sugars for PHB production. The pretreatment competence was determined using various operational parameters. By applying ambient conditions, alkaline pretreatment gave higher lignin removal of 65.0%, with 80.8% hydrolysis yield, and on enzyme hydrolysis (40 FPU/g of dry WH), produced total reducing sugar of about 523 mg/g of WH. The resulted WH enzymatic hydolysates were evaluated for the production of PHB by Ralstonia eutropha (ATCC 17699). The WH hydrolysates cultivation was compared to synthetic hydrolysates that contain a similar carbon composition in terms of bacterial growth and PHB synthesis. The effects of various supplements to enhance PHB production were estimated. Supplementation of corn steep liquor (CSL) as a cheap nitrogen source with WH hydrolysates favored a higher amount of PHB synthesis (73%), PHB titer of 7.30 g/L and PHB yield of 0.429 g/g of reducing sugar. Finally, using standard analytical tools, the physical and thermal characteristics of the extracted PHB were evaluated. The findings revealed WH was a promising and technically feasible option for transforming biomass into sustainable biopolymer conversion on a large scale.

Highlights

Durability and extraordinary mechanical and thermal properties make conventional plastics useful for many applications
Water hyacinth is regarded as a malicious aquatic weed because of its speedy proliferation and ecological adaptability which creates severe impacts on the aquatic ecosystem and socio-economic progress [12,24]
In water hyacinth biomass (WH) biomass, mainly cellulose and hemicellulose components can be converted into fermentable sugars after enzymatic hydrolysis

Summary

Introduction

Durability and extraordinary mechanical and thermal properties make conventional plastics useful for many applications. They are not readily biodegradable and accumulate in the environment and directly lead to waste disposal problems [1]. Biopolymers, notably polyhydroxyalkanoates (PHAs), can address numerous global environmental problems, for instance, ocean pollution and greenhouse gas emissions, as they can biodegrade into harmless products in various environments such as home compost, anaerobic digestion, and marine environments within a short time. Biodegradability makes PHAs an ideal substitute for conventional polymers in single-use products [5,6]. A significant development can be foreseen in the short- and long-term future for bio-based products [7]

Objectives

Methods

Results

Conclusion