Related Experiment Video
Updated: Mar 12, 2026
Production of Chemicals by Klebsiella pneumoniae Using Bamboo Hydrolysate as Feedstock
Published on: June 29, 2017
Polymalic acid fermentation by Aureobasidium pullulans for malic acid production from soybean hull and soy molasses:
Chi Cheng1, Yipin Zhou2, Meng Lin3
1William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH 43210, USA.
Abstract:
Polymalic acid (PMA) production by Aureobasidium pullulans ZX-10 from soybean hull hydrolysate supplemented with corn steep liquor (CSL) gave a malic acid yield of ∼0.4g/g at a productivity of ∼0.5g/L·h. ZX-10 can also ferment soy molasses, converting all carbohydrates including the raffinose family oligosaccharides to PMA, giving a high titer (71.9g/L) and yield (0.69g/g) at a productivity of 0.29g/L·h in fed-batch fermentation under nitrogen limitation. A higher productivity of 0.64g/L·h was obtained in repeated batch fermentation with cell recycle and CSL supplementation. Cost analysis for a 5000 MT plant shows that malic acid can be produced at $1.10/kg from soy molasses, $1.37/kg from corn, and $1.74/kg from soybean hull. At the market price of $1.75/kg, malic acid production from soy molasses via PMA fermentation offers an economically competitive process for industrial production of bio-based malic acid.
Insights
Aureobasidium pullulans ZX-10 efficiently produces polymalic acid (PMA) from soy molasses, yielding high concentrations of bio-based malic acid. This fermentation process is economically competitive for industrial-scale production.
Area of Science:
- Biotechnology
- Industrial Microbiology
- Biochemical Engineering
Background:
- Polymalic acid (PMA) is a biopolymer with various applications.
- Efficient microbial production of malic acid is crucial for its industrial viability.
- Soy-based feedstocks offer potential for sustainable bioprocessing.
Purpose of the Study:
- To optimize polymalic acid (PMA) production by Aureobasidium pullulans ZX-10.
- To evaluate the economic feasibility of bio-based malic acid production from different feedstocks.
- To enhance fermentation productivity through process optimization.
Main Methods:
- Fermentation of Aureobasidium pullulans ZX-10 using soybean hull hydrolysate and corn steep liquor (CSL).
- Fed-batch fermentation of soy molasses with nitrogen limitation.
- Repeated batch fermentation with cell recycle and CSL supplementation.
- Cost analysis for industrial-scale malic acid production.
Main Results:
- Malic acid yield of ~0.4g/g and productivity of ~0.5g/L·h from soybean hull hydrolysate.
- High titer (71.9g/L) and yield (0.69g/g) from soy molasses in fed-batch fermentation.
- Enhanced productivity of 0.64g/L·h via repeated batch fermentation with cell recycle and CSL.
- Cost-effective production at $1.10/kg from soy molasses.
Conclusions:
- Aureobasidium pullulans ZX-10 is a robust strain for producing polymalic acid from diverse soy-based feedstocks.
- Fermentation of soy molasses offers a highly efficient and economically competitive route to bio-based malic acid.
- Process optimization, including cell recycle and CSL supplementation, significantly boosts productivity.
Related Concept Videos
01:14Alkylation of β-Diester Enolates: Malonic Ester Synthesis
01:23Microbial Fermentation
01:35Loss of Carboxy Group as CO2: Decarboxylation of Malonic Acid Derivatives
01:18Amino Acid Catabolism
01:20Fates of Pyruvate
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...