Related Experiment Video
Updated: Sep 26, 2025
Production of Chemicals by Klebsiella pneumoniae Using Bamboo Hydrolysate as Feedstock
Published on: June 29, 2017
Efficient poly(β-L-malic acid) production from cassava hydrolysate by cell recycle of Aureobasidium pullulans
Wei Liu1,2, Zhenjun Si2, Huili Zhang2
1College of Food Science and Light Industry, Nanjing Tech University, Nanjing, 211816, China.
Abstract:
Poly(β-L-malic acid) (PMLA) is a water-soluble, biodegradable, and biocompatible polymer with broad prospective applications and can be hydrolyzed to produce widely used acidulant L-malic acid. In order to meet an increasing demand of PMLA, we employed two effective cell-recycling strategies to produce PMLA from raw cassava hydrolysate by Aureobasidium pullulans ZD-3d. In fed-batch fermentation with raw cassava hydrolysate, 101.9 g/L PMLA was obtained with the productivity and yield of 0.77 g/L/h and 0.40 g/g, respectively. Further, three times of membrane filtration-based cell recycling fermentation was carried out, with a high productivity and yield of 1.04-1.64 g/L/h and 0.5-0.84 g/g achieved, respectively. While harnessing centrifugation-based cell recycling fermentation for five times, the productivity and yield approached 0.98-1.76 g/L/h and 0.78-0.86 g/g, respectively. To our knowledge, the processes showed the highest average PMLA productivity compared with others using low-cost biomass, which offered efficient and economical alternatives for PMLA production. KEY POINTS: • PMLA production from raw cassava hydrolysate by Aureobasidium pullulans was studied • High PMLA productivity and yield were obtained via two cell recycling strategies • The highest average PMLA productivity from low-cost biomass to date was achieved.
Insights
Poly(β-L-malic acid) (PMLA) production was optimized using Aureobasidium pullulans and raw cassava. Cell recycling strategies significantly enhanced PMLA productivity and yield, offering economical alternatives for industrial applications.
Area of Science:
- Biotechnology and Industrial Microbiology
- Polymer Science
- Bioprocess Engineering
Background:
- Poly(β-L-malic acid) (PMLA) is a valuable biodegradable polymer with diverse applications, including its hydrolysis to L-malic acid.
- Increasing demand for PMLA necessitates efficient and cost-effective production methods.
- Aureobasidium pullulans is a microbial producer of PMLA, and raw cassava hydrolysate presents a low-cost substrate.
Purpose of the Study:
- To investigate and optimize Poly(β-L-malic acid) (PMLA) production from raw cassava hydrolysate using Aureobasidium pullulans.
- To evaluate the effectiveness of cell recycling strategies in enhancing PMLA productivity and yield.
- To establish efficient and economical alternatives for large-scale PMLA manufacturing.
Main Methods:
- Fed-batch fermentation of Aureobasidium pullulans ZD-3d using raw cassava hydrolysate.
- Implementation of membrane filtration-based cell recycling for enhanced fermentation.
- Application of centrifugation-based cell recycling for repeated fermentation cycles.
Main Results:
- Fed-batch fermentation achieved 101.9 g/L PMLA with a productivity of 0.77 g/L/h and yield of 0.40 g/g.
- Membrane filtration cell recycling yielded 1.04-1.64 g/L/h productivity and 0.5-0.84 g/g yield.
- Centrifugation cell recycling achieved 0.98-1.76 g/L/h productivity and 0.78-0.86 g/g yield, demonstrating superior performance.
Conclusions:
- Cell recycling strategies, particularly centrifugation, significantly improve PMLA productivity and yield from low-cost biomass.
- The developed processes represent the highest average PMLA productivity reported to date using inexpensive feedstocks.
- These findings offer efficient and economically viable methods for industrial PMLA production.
