Fumaric acid production from hydrolysates of starch-based substrates

Area of Science:

• Biotechnology
• Industrial Microbiology
• Biochemical Engineering

Background:

• Fumaric acid is a valuable organic acid with diverse industrial applications.
• Optimizing fermentation conditions is crucial for cost-effective production of fumaric acid.
• Rhizopus arrhizus is a known producer of fumaric acid.

Purpose of the Study:

• To investigate the impact of initial glucose concentration and C:N ratio on fumaric acid production by Rhizopus arrhizus.
• To determine optimal fermentation parameters for maximizing fumaric acid yield and productivity.
• To evaluate the performance of optimized conditions with various starch-based substrates.

Main Methods:

• A 3(2) factorial experiment was conducted to study fumaric acid production.
• Response surface methodology and statistical analysis were employed to model yields and productivity.
• Optimal operating conditions were validated using different glucose and hydrolysate substrates.

Main Results:

• Fumaric acid (YF) and biomass (YX) yields, and fumaric acid productivity (PF) were significantly influenced by glucose concentration (S) and C:N ratio (R).
• Optimal ranges for S and R were determined as 100-130 g dm-3 and 150-210 g-atom C per g-atom N, respectively.
• The optimal condition (S=120, R=150) yielded significant improvements in YF (40-49%) and PF (7-8.5 g dm-3 day-1) across various starch hydrolysates.

Conclusions:

• The study established empirical models to predict fumaric acid production based on S and R.
• Optimized fermentation conditions significantly enhance fumaric acid yield and productivity.
• Utilizing acid hydrolysates of starch-based materials under optimized conditions offers a cost-effective strategy for fumaric acid production.