maintenance by adding neutralizers with glucose as the substrate, and immobilization technique with the cells or enzymes, the yield could be enhanced drastically than
any other methods [59]. The disadvantage in the fermentation process is the purification and separation technique results in the development of the classical methods
to reduce the cost of the downstream process [57]. Also, many studies have focused
on the agro-based by-products to be used as the substrate to meet the demand and to
reduce the cost since they are readily available in abundance with eco-friendlier
nature [58].
6.3 Fumaric Acid
Fumaric acid is mainly the intermediary product produced in the tricarboxylic acid
and are mainly used as beverages in the food industries. Fumaric acid could either be
produced from the chemical synthesis and fermentative methods. Also, these could
be produced as the by-products from the microbial sources as the result of oxidative
metabolism [60]. Rhizopus is mainly used with numerous substrates like starch,
molasses, sucrose, and glucose in the fermentation phenomena to produce a sufficient quantity of fumaric acid [60]. It could also be synthesized from the maleic acid
isomerization and are mainly used in manufacturing the different resins which could
be used in the paper industry [61].
The other acids like glucaric acid, galactonic acid, and lactobionic acid are
produced in the very less quantity by the chemical methods and by the microbial
sources is shown in Table 6. Glucose is the majorly used substrate used to produce
these acids by fermentation phenomena. Microbial sources like Pseudomonas,
Gluconobacter, Aspergillus niger, E. coli, and Streptomyces cerevisiae involved in
the large-scale production on commercial purposes [62].
7 Production of Organic Acids by Genetically Engineered
Organisms
Numerous approaches like genome shuffling and random mutagenesis have been
widely used in the wild-type strain to increase the optimum yield of the various
organic acid productions [69]. It is one of the evolutionary methods that limit the
Table 5 Numerous applications in the production of succinic acid
Application
% usage of succinic acid in the market
Plasticizer
9.0
Polybutylene succinate
13.0
Solvent and lubricant
9.5
Polyols
7.0
Pharmaceutical
15.0
Other industrial usages
15.0
78
D. Vishnu et al.
any other methods [59]. The disadvantage in the fermentation process is the purification and separation technique results in the development of the classical methods
to reduce the cost of the downstream process [57]. Also, many studies have focused
on the agro-based by-products to be used as the substrate to meet the demand and to
reduce the cost since they are readily available in abundance with eco-friendlier
nature [58].
6.3 Fumaric Acid
Fumaric acid is mainly the intermediary product produced in the tricarboxylic acid
and are mainly used as beverages in the food industries. Fumaric acid could either be
produced from the chemical synthesis and fermentative methods. Also, these could
be produced as the by-products from the microbial sources as the result of oxidative
metabolism [60]. Rhizopus is mainly used with numerous substrates like starch,
molasses, sucrose, and glucose in the fermentation phenomena to produce a sufficient quantity of fumaric acid [60]. It could also be synthesized from the maleic acid
isomerization and are mainly used in manufacturing the different resins which could
be used in the paper industry [61].
The other acids like glucaric acid, galactonic acid, and lactobionic acid are
produced in the very less quantity by the chemical methods and by the microbial
sources is shown in Table 6. Glucose is the majorly used substrate used to produce
these acids by fermentation phenomena. Microbial sources like Pseudomonas,
Gluconobacter, Aspergillus niger, E. coli, and Streptomyces cerevisiae involved in
the large-scale production on commercial purposes [62].
7 Production of Organic Acids by Genetically Engineered
Organisms
Numerous approaches like genome shuffling and random mutagenesis have been
widely used in the wild-type strain to increase the optimum yield of the various
organic acid productions [69]. It is one of the evolutionary methods that limit the
Table 5 Numerous applications in the production of succinic acid
Application
% usage of succinic acid in the market
Plasticizer
9.0
Polybutylene succinate
13.0
Solvent and lubricant
9.5
Polyols
7.0
Pharmaceutical
15.0
Other industrial usages
15.0
78
D. Vishnu et al.