Fumaric acid, production and

In the present study, we evaluated a two-step process for succinic acid production. The first process was fumaric acid production by Rhizopus sp. using rice bran, and the second process was succinic acid production by Enterococcus faecalis RKY1 (5-7) using fungal culture broth obtained in the first process. We investigated the effects of rice bran on fumaric acid production and optimized the culture medium for fumaric acid fermentation. Furthermore, we optimized the culture conditions for succinic acid conversion from fumaric acid produced by the first process. 

Another way to improve morphology of Rhizopus species utilizes immobilization techniques for the possibility of a continuous operation mode for fumaric acid production and to reduce oxygen transfer problems. ... 

FUMARIC ACID PRODUCTION AND APPLICATION ASPECTS TABLE 8.6 Different Immobilization-Based Studies for Fumaric Acid Production ... 

Maleic anhydride and the two diacid isomers were first prepared in the 1830s (1) but commercial manufacture did not begin until a century later. In 1933 the National Aniline and Chemical Co., Inc., installed a process for maleic anhydride based on benzene oxidation using a vanadium oxide catalyst (2). Maleic acid was available commercially ia 1928 and fumaric acid production began in 1932 by acid-catalyzed isomerization of maleic acid. 

Acetylenedicarboxylic acid is known to combine with a number of pyrroles but only in the case of 1-benzylpyrrole have the products been rigorously examined. Mandell and Blanchard showed that in this case a mixture of the maleic anhydride (35), the fumaric acid (36), and the Diels-Alder type adduct (38) was formed. 

A large amount of rice bran caused excessive fungal growth rather than enhance fumaric acid production. In addition, we could produce fumaric acid without the addition of zinc and iron. Fungal culture broth containing approx 25 g/L of fumaric acid was directly employed for succinic acid conversion. The amount of glycerol and yeast extract required for succinic acid conversion was reduced to 70 and 30%, respectively, compared with the amounts cited in previous studies. 

To optimize the culture medium for fumaric acid production, we investigated the effects of rice bran concentrations and various carbon sources. When rice bran was used as a nitrogen source, the effects of additional elements (phosphate, magnesium, zinc, and iron) on fumaric acid production were also investigated. The medium previously reported by Zhou et al. (11) was used as the basal medium. Fermentations were performed in 250-mL Erlenmeyer flasks containing 100 mL of medium. 

Effect of Phosphate, Magnesium, Zinc, and Iron on Fumaric Acid Production Using Rice Bran ... 

With the use of rice bran as a nitrogen source, we studied the effect of phosphate, magnesium, zinc, and iron on fumaric acid production. Although magnesium, zinc, and iron did not cause any effect (Mg2+ trials 1 and 4, Zn2+ trials 1 and 3, Fe2+ trials 1 and 2), phosphate was crucial to fumaric acid production (trials 12 and 16). 

Batch fermentations were carried out using rice bran and glucose as nitrogen and carbon sources, respectively. Figure 4 shows the profile of fumaric acid production in a 2.5-L jar fermentor. The fumaric acid concentration reached 25.3 g/L. The yield (fumaric acid produced/glucose consumed) and the productivity were 52% and 0.21 g/(L-h), respectively. For the following experiment, the fungal culture broth was used as a medium for the bioconversion of fumaric acid into succinic acid. 

Fig. 5. Effect of glycerol concentration on succinic acid production, fumaric acid consumption, and cell growth. The culture conditions were as follows 50-mL vial (40 mL of medium) 15 g/L of yeast extract 5 g/L of K2HP04 initial pH of 7.0.

Finally, we investigated the inhibition of concentrated fungal culture broth on succinic acid production and fumaric acid consumption. As shown in Fig. 8, we found that concentrated fungal culture broth slightly inhibited the bacterial conversion. Succinic acid could be efficiently produced from fungal culture broth until it was concentrated to three-fold (64 g/L of fumaric acid). However, the conversion time needed was severely prolonged when it was concentrated to more than four-fold (84 g/L of fumaric acid). Since E.faecalis RKY1 could efficiently convert fumaric acid... 

Palladium on carbon (10%, 0.10g) was added to a solution of the Step 4 product (2.0 mmol) in methyl alcohol and stirred 18 hours at room temperature under a hydrogen atmosphere. The mixture was filtered through a filter aid, concentrated, and the residue isolated in 96% yield. The residue was converted into the fumaric acid salt and crystallized from methyl alcohol/diethyl ether and the product isolated as a colorless solid, mp = 150-152°C. 

Zhou, Y., Du, J., and Tsao, G.T. 2002. Comparison of fumaric acid production by Rhizopus oryzae using different neutralizing agents. Bioprocess and Biosystems Engineering 25 179-181. 

Fumaric acid production using immobilized Rhizopus cells has also been studied. Petruccioli et al. [74] immobilized R. arrhizus NRRL 1526 on polyurethane sponge to carry out repeated batch fumaric acid production from glucose syrup with KOH/KCO3 as the neutralization agent and CO2 source. Although the yield (12.3 g/1) is low, it provides the possibility of using immobilized Rhizopus for the continuous production of fumaric acid. 

Fumaric acid production from starch hydrolysate by R. arrhizus NRRL 1526 was studied by Federici et al. [75] in a 3-1 stirred-tank fermentor with CaCO, and KOH/KCO3 as the neutralizing agent and CO2 source. The fermentation conditions for fumaric acid production by this fungus from potato flour has been optimized by Moresi et al. [76]. 

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