2. • All living organisms get the energy required to
perform cellular functions by respiration.
• In most of the animals, respiration occurs in
the presence of oxygen (aerobically). Some
organisms like bacteria, yeast, etc. can
produce energy in the absence of oxygen
(anaerobically).
3. Metabolites
• Small molecules
• Intermediate products produced during
metabolism
• The various functions of metabolites include;
fuel, structure, signalling, catalytic activity,
defence and interactions with other
organisms.
4. Primary metabolite Secondary metabolite
required for the growth and maintenance
of cellular function
not required for the growth and
maintenance of the cellular functions
Also known as Trophophase Also known as Idiophase
Occurs at growth phase Occurs at stationary phase
These are produced in large quantities These are produced in small quantities
extraction is easy extraction is difficult
produce the same products in every
species
Produce different products depending on
the species
play the significant role in the cell growth,
reproduction and development.
indirectly support the cell, in sustaining
their life for long duration.
Vitamins, carbohydrates, proteins,
alcohols, organic acids and lipids
Antibiotics, Phenolics, steroids,
gibberellins, essential oils, alkaloids
5. • Fermentation term was coined by Louis Pasteur
for a phenomenon of bubbling of sugar solution.
• Fermentation is an anaerobic process
• Fermentation is an enzyme catalysed, metabolic
process whereby organisms convert starch or
sugar to alcohol or an acid anaerobically releasing
energy.
• The science of fermentation is called “zymology”
6. Biochemical Process
• In fermentation, the first process is the same
as cellular respiration, which is the formation
of pyruvic acid by glycolysis where net 2 ATP
molecules are synthesised.
• In the next step, pyruvate is reduced to lactic
acid, ethanol or other products. Here NAD+ is
formed which is re-utilized back in the
glycolysis process.
7.
8. Types
• Homo fermentation : only one type of product
formation
• Hetero fermentation: more than one product
formed
• Based on end products it can be categorized into
– Lactic acid fermentation
– Alcoholic fermentation
– Acetic acid Fermentation
– Butyric acid Fermentation
– Formic acid fermentation
– Propionic acid fermentation
– Acetic acid fermentation
– Gluconic acid fermentation
9. • Alcoholic fermentation
– Many fungi and some bacteria, algae, and
protozoa ferment sugars to ethanol and CO2 in a
process called Alcoholic fermentation.
– Alcoholic fermentation by yeasts produces
alcoholic beverages; CO2 from this fermentation
causes bread to rise.
• Lactic acid fermentation
– Lactic acid fermentation, the reduction of
pyruvate to lactate
10. • Formic acid fermentation
– can metabolize Pyruvate to Formic acid and other
products in a process sometimes called the Formic
acid fermentation.
• Butyric acid fermentation
– The fermentation of Carbohydrates with the
predominant formation of Butyric acid is causes by
many Anaerobic bacteria belonging to the genus
Clostridium
• Propionic acid fermentation
– The bacteria Propionibacterium sp. coverts the
Succinic acid to Propionic acid, Acetic acid and CO2.
11. • Acetic acid fermentation
– Bacteria of the genus Acetobacter sp. oxidize
Ethanol to Acetic acid.
• Gluconic acid fermentation
– Certain mold fungi capable of oxidizing the
aldehydes group of Glucose to Gluconic acid.
13. • Two main steps/stages
– Up-stream process
– Downstream process
• Upstream process comprises of obtaining a
desired microorganism, and its improvement
so as to enhance the productivity and yield. It
also includes the maintenance of strain purity,
preparation of inocula and further efforts to
improve the economic efficiency of the
process.
14.
15. • Downstream process includes the selection of
suitable fermentation media, optimization of
important fermentation condition to give rise
maximum yield and recovery.
17. • A batch fermentation is a closed culture system,
because initial and limited amount of sterilized
nutrient medium is introduced into the
fermenter. Batch fermentation may be used to
produce biomass, primary metabolites and
secondary metabolites under cultural conditions.
• A continuous fermentation is a closed system of
fermentation, run for indefinite
period. Continuous culture fermentation has
been used for the production of single cell
protein, antibiotics, organic solvents, starter
cultures etc.
18. • Fed Batch fermentation is a modification to the
batch fermentation. Fed-batch with recycle of
cells can also be used for specific purpose such as
ethanol fermentation and waste water treatment.
• A fermentation process carried out in the
absence of oxygen is called as anaerobic
fermentation. Anaerobic conditions in the
fermenter are created either by withdrawing the
oxygen present in the head space by an exhaust
pump and pumping some inert gases like
nitrogen, argon etc.
19. • A fermentation process carried out in the
presence of oxygen is called as aerobic
fermentation.
• Surface fermentations are those where the
substratum may be solid or liquid. These types of
fermentations are desirable where the products
are based on sporulation.
• Submerged Fermentations are those in which the
nutrient substratum is liquid and the organism
grows inside the substratum. Most of the
industrial fermentations are of this type.
20. • Solid state (substratum) fermentation (SSF) is
generally defined as the growth of the
microorganism on moist solid materials in the
absence or near the absence of free water.
Enzymes, bread making, antibiotic production,
sewage treatment, steroid production can all
be produced using this type