compounds have proven to be used in the numerous applications as additives in the
food industries and due to their major demand as the feedstocks in the chemical
industries. These compounds are also used as the silages in the perspective of
drinking water. Organic acids could be produced through chemical and microbiological processes. But fermentation is considered as the major phenomena in the
commercial large-scale production of numerous organic acids. Mostly genetically
engineered strains could produce the high yield of organic acids using alternate
residues from the chemical feedstocks. The choice of raw material and microbial
sources is considered as the major significant factor for the enhanced productivity
and yield, especially in the large-scale production. Mainly solid-state fermentation
with renewable source as the feedstock was preferred because of the economic factor
of low cost and easy availability. Citric acid is considerably produced in large
quantities among the other acids with 1.6 million tons, whereas acetic acid and
lactic acid constitute to be the second and third place in the productivity of various
organic acids. These organic acids are extensively found to be used in the numerous
applications of food industries, dairy products, and pharmaceuticals and also in the
production of various components like inks, plastics, lacquers, etc.; they play a
prominent role as a chelating agent in the removal of various metal pollutants
from soil. The cost of the petrochemical derivatives tends to increase the usage
and provokes the strong interest toward the agricultural by-products to be used as the
major feedstock in the numerous organic acid production. These agricultural
by-products are considered to be both renewable and economically cheap material
as the feedstock to be easily consumed by numerous microorganisms in the commercial and large-scale production of various organic acids.
Keywords Agricultural by-products, Cost and production, Feedstock, Microbial
sources, Organic acids, Petrochemical derivatives
1 Introduction
Organic acids (OA) are considered to be the primary groups in the building block of
chemicals. They are synthesized from the numerous renewable materials by using
microbial phenomena [1]. Mainly they are produced either as the intermediaries
during microbial synthetic pathways else occur as the natural products that could be
secreted by the various microbes [2]. OA, as well as their derived products, are
extensively used in the chemical industries across worldwide due to their unique
functional groups which pave a way to emerge in the market [3]. The production of
OA and their derivatives could widely be used as the alternative source of numerous
petroleum-derived commodities. Maleic anhydride could be replaced with various
organic acids of fumaric, malic, and succinic acids which are considered to be more
economical, and it tends to provoke the interest on the production of OA in the
markets [4].
Agro-industrial wastes are prominently considered among the various industrial
by-products due to their abundant carbon and oxygen contents as well as the
68
D. Vishnu et al.
food industries and due to their major demand as the feedstocks in the chemical
industries. These compounds are also used as the silages in the perspective of
drinking water. Organic acids could be produced through chemical and microbiological processes. But fermentation is considered as the major phenomena in the
commercial large-scale production of numerous organic acids. Mostly genetically
engineered strains could produce the high yield of organic acids using alternate
residues from the chemical feedstocks. The choice of raw material and microbial
sources is considered as the major significant factor for the enhanced productivity
and yield, especially in the large-scale production. Mainly solid-state fermentation
with renewable source as the feedstock was preferred because of the economic factor
of low cost and easy availability. Citric acid is considerably produced in large
quantities among the other acids with 1.6 million tons, whereas acetic acid and
lactic acid constitute to be the second and third place in the productivity of various
organic acids. These organic acids are extensively found to be used in the numerous
applications of food industries, dairy products, and pharmaceuticals and also in the
production of various components like inks, plastics, lacquers, etc.; they play a
prominent role as a chelating agent in the removal of various metal pollutants
from soil. The cost of the petrochemical derivatives tends to increase the usage
and provokes the strong interest toward the agricultural by-products to be used as the
major feedstock in the numerous organic acid production. These agricultural
by-products are considered to be both renewable and economically cheap material
as the feedstock to be easily consumed by numerous microorganisms in the commercial and large-scale production of various organic acids.
Keywords Agricultural by-products, Cost and production, Feedstock, Microbial
sources, Organic acids, Petrochemical derivatives
1 Introduction
Organic acids (OA) are considered to be the primary groups in the building block of
chemicals. They are synthesized from the numerous renewable materials by using
microbial phenomena [1]. Mainly they are produced either as the intermediaries
during microbial synthetic pathways else occur as the natural products that could be
secreted by the various microbes [2]. OA, as well as their derived products, are
extensively used in the chemical industries across worldwide due to their unique
functional groups which pave a way to emerge in the market [3]. The production of
OA and their derivatives could widely be used as the alternative source of numerous
petroleum-derived commodities. Maleic anhydride could be replaced with various
organic acids of fumaric, malic, and succinic acids which are considered to be more
economical, and it tends to provoke the interest on the production of OA in the
markets [4].
Agro-industrial wastes are prominently considered among the various industrial
by-products due to their abundant carbon and oxygen contents as well as the
68
D. Vishnu et al.