Developing Microbial Co-Culture System for Enhanced Polyhydroxyalkanoates (PHA) Production Using Acid Pretreated
Rijuta Ganesh Saratale1, Si-Kyung Cho2, Avinash Ashok Kadam1
1Research Institute of Biotechnology and Medical Converged Science, Dongguk University-Seoul, Ilsandong-gu, Goyang-si 10326, Gyeonggi-do, Korea.
Polymers
|February 26, 2022
Summary
This study optimized polyhydroxyalkanoates (PHA) bioplastics production from sugarcane bagasse using a microbial co-culture. Co-culturing enhanced sugar utilization and PHA yield, demonstrating a sustainable bioplastics production method.
Area of Science:
- Biotechnology and Bioengineering
- Polymer Science
- Microbiology
Background:
- The polymer industry seeks biodegradable and biocompatible bioplastics.
- Polyhydroxyalkanoates (PHA) are promising bioplastics derived from microbial fermentation.
- Agricultural waste, like sugarcane bagasse (SCB), offers a sustainable feedstock for bioplastics production.
Purpose of the Study:
- To evaluate PHA production by individual microbial strains and a co-culture using SCB hydrolysates.
- To optimize SCB pretreatment and co-culture conditions for enhanced PHA yield.
- To investigate the impact of nutrient supplementation on PHA synthesis.
Main Methods:
- Sugarcane bagasse (SCB) pretreatment using acidic and acidified sodium chlorite methods.
- Enzymatic hydrolysis of SCB to produce fermentable sugars.
- Polyhydroxyalkanoates (PHA) production by individual and co-cultures of *Lysinibacillus* sp. RGS and *Ralstonia eutropha* ATCC 17699.
- Optimization of hydrolysate concentration and supplementation with nutrients (corn steep liquor, spent coffee waste extracted oil) and volatile fatty acids (VFAs).
Main Results:
- Acidic pretreatment achieved 60% delignification and a maximum hydrolysis yield of 74.9%.
- Co-culture demonstrated superior sugar assimilation, bacterial growth, and PHA production kinetics compared to individual strains.
- Optimal conditions with nutrient supplementation yielded maximum cell growth (11.68 g/L), PHA accumulation (76%), and PHA titer (8.87 g/L).
Conclusions:
- A microbial co-culture strategy using SCB hydrolysates is effective for efficient PHA bioplastics production.
- Optimization of pretreatment and co-culture conditions significantly enhances PHA yield.
- Utilizing agricultural waste like SCB for PHA production offers a sustainable and cost-effective approach.
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