Polysaccharides are the carbon sources which are found in huge amount in the biosphere used for food, pharmaceutical, and medical applications derives from the great diversity in structural and functional properties. xanthan, xylinan, gellan, curdlan, pullulan, dextran, scleroglucan, schizophyllan, and cyanobacterial polysaccharides The commercial value of polysaccharides is based on its ability to modify the flow characteristics of solutions (Rheology). They can incr viscosity and hence used as thickening and gelling agents.

1. FERMENTATION & INDUSTRIAL MICROBIOLOGY
MICROBIAL POLYSACCHARIDE, TYPES ,
PRODUCTION AND APPLICATION
N. MUTHUGANESAN
BTM14010

2. Introduction
• Polysaccharides are the carbon sources which are found in huge
amount in the biosphere
• used for food, pharmaceutical, and medical applications
• derives from the great diversity in structural and functional properties.
• xanthan, xylinan, gellan, curdlan, pullulan, dextran, scleroglucan,
schizophyllan, and cyanobacterial polysaccharides
• The commercial value of polysaccharides is based on its ability to
modify the flow characteristics of solutions (Rheology).
• They can incr viscosity and hence used as thickening and gelling
agents.

3. • Polysaccharides made by microrganisms are secreted from the cell to
form a layer over the surface of the organism,
• Certain microbes are known to produce nearly all the major
plant polysaccharides such as glucans, alginate-like materials

4. TYPE OF MICROBIAL POLYSACCHARIDE
Capsular polysaccharides
• protective capsule and thus
prevent the pathogenic micro-
organism from immune system
defenses.
• act as barrier in preventing the
harmful intruders
Exo-polysaccharides
• that are secreted out by the
micro-organisms
• are however evolved to avoid
any antibody responses.

5. Cont……
As extracting these polysaccharides at low cost in larger
quantities makes it more useful in any research industries
Bulk amount of these microbial polysaccharides are used in
food industry such as xanthan to dextran
Due to their unique structure and physical properties they
are widely used as emulsifiers, stabilizers, thickeners, viscosifiers,
film-formers and gelling agents

6. Microbial Polysaccharide MOs
Xanthan Xanthomonas Campestris
Gellan Sphingomonas paucimobilis
Pullulan Aureobasidium pullulans
Dextran Leuconostoc Mesenteroides and
Leuconostoc Dextranicum
Xylinan/Acetobacter xylinum
cellulose
Acetobacter xylinum
Alginates
Azotobacter chroococcum and
Azotobacter vinelandii
Curdlan Alcaligenes faecalis

7. Microbial PS
Plant PS
Cheap
Uncontrolled
Occurs for a short duration
20 PS of commercial adv and value
Dependent of rheological property
Only microbial polysaccharide currently
produced on a Large scale: XANTHAN

8. PRODUCTION OF XANTHAN GUM

9. • natural polysaccharide and an important industrial biopolymer
• It was discovered in the 1950s at the Northern Regional Research
Laboratories (NRRL)
• produced by the bacterium Xanthomonas campestris
• Heteropolysaccharide with a primary structure consisting of repeated
pentasaccharide units formed by two glucose units, two mannose
units, and one glucuronic acid units.

10. Process
• First, the selected microbial strain is preserved for possible long-term
storage by proven methods to maintain the desired properties.
• A small amount of the preserved culture is expanded by growth on
solid surfaces or in liquid media to obtain the inoculum for large
bioreactors.
• aerobic fermentation process
• such as the type of bioreactor used, the mode of operation (batch or
continuous),
• the medium composition, and the culture conditions (temperature,
pH, dissolved oxygen concentration).

11. Maintain stain Xanthomonas campestris Growth
InoculumBio reactorProduction medium and
operational conditions
Fermentation broth
Pasteurization
Cell removal
Precipitation
Separation
Washing, dewatering
and drying
Xanthan gum
Distillation
Alcohol or agent
Alcohol or agent
Alcohol or agent

12. Fermentation conditions
• X. campestris needs several nutrients, including micronutrients (e.g.
potassium, iron, and calcium salts) and macronutrients such as
carbon and nitrogen.
• Glucose and sucrose are the most frequently used carbon source
concentration of 2-4% is preferred
• Growth temperature X. campestris has been cultured at different
temperatures ranging from 25 to 30°C
• pH decreases from neutral pH to values close to 5 because of acid
groups present in xanthan.
• sparged stirred tank is employed most frequently. When the stirrer
speed was constant at < 500 rpm,

13. • At the end of the fermentation, the broth contains xanthan, bacterial
cells, and many other chemicals.
• For recovering the xanthan, the cells are usually removed first, either
by filtration or centrifugation (Flores Candia and Deckwer, 1999).
• Further purification may include precipitation using water-miscible
non-solvents (isopropanol, ethanol, acetone), addition of certain
salts, and pH adjustments (Flores Candia and Deckwer, 1999).
• The FDA regulations for food grade xanthan gum prescribe the use of
isopropanol for precipitation
• After precipitation, the product is mechanically dewatered and dried.
Downstream processing

14. Xanthan gum
• The high viscosity at very low concentrations makes it an excellent agent as food additive for
syruping, stabilizer and as a thickening agent
• low calorie drinks which increase the thinning consistency where the total or partial sugars are
replaced by artificial sweeteners
• stabilizer in most liquid and semi-liquid foods and gives a body form to most dairy products
• freeze thaw stability its major food additive in frozen food industries.
• extensively used in bakery products to help retention of water in baking food and therefore
increases the shelf life of the food
• It’s used in low fat food to increase the viscosity of the aqueous phase and stabilize the food
system
• mayonnaise, cheese, ready-to-eat meals etc.
• Xanthan was approved by FDA as food additive
• it’s widely used in commercial food industry.

16. Gellan
• synthesized by bacterium Sphingomonas paucimobilis
• It was approved by FDA as a food additive in the year 1992
• used as stabilizer, gelling agent and as thickening agent in many food sources.
• It provides structure; texture and mouth feel in many food substances rather than gelatin.
• It’s mostly used in confectionary units to reduce the set time of gelling such as starch jellies
• prevents the moisture loss in these sugary foods.
• Gellan can replace pectin in jams with low concentrations use when compared to pectins.
• modified starch food to increase the stability as stabilizer and water binding agent preventing the
“blunting effect”
• Fabricated food like
• meat, fruits, confectioneries fall into this category.

17. Polysaccharide Food in which used Concentration required(%) Functionality

18. Pullulan
• Pullulan is a type of exo-polysaccharide which is derived from a
fungus Aureobasidium pullulans
• A white to off-white tasteless, odorless powder that forms a viscous
non-hygroscopic solution when dissolved in water at 5-10%.
• used in the production of capsule shells as well as coated tablets for
the preparation of dietary supplements.
• It has particularly used to make snack foods in Japan which are based
on cod roe and powdered cheese
• used at low doses as it is slowly digested in humans
• It is used to make packaging film for ham

19. Polysaccharide Food in which used Concentration
required(%)
Functionality

20. Dextran
• Dextran is a linear polysaccharide which is obtained from the
Leuconostoc Mesenteroides,
• It is the first microbial polysaccharide that has got commercialized
and approved for used in food.
• It is used in pudding mixes to provide them with texture and mouth
feel.

21. Polysaccharide Food in which used Concentration
required(%)
Functionality

22. Xylinan/Acetobacter xylinum cellulose
• Xylinan is the microbial exo-polysaccharide i.e.
• Obtained from the Acetobacter xylinum gram-negative bacteria.
• This component has made its place in the food industry as
viscosifying and gelling agent having high gel strength, water-holding
capacity and is easy to mold.
• Actually, it is the major component in nata de coco, a confectionery
which is widespread in Japan and Philippines.
Polysaccharide Food in which used Concentration required(%) Functionality

23. Alginates
• mainly from the liquid bacterial cultures such as Pseudomonas
aeruginosa, Azotobacter chroococcum and Azotobacter vinelandii
• one as they can be used for large-scale industrial production of
alginates
• aeruginosa which is an infective agent which is found to be associated
with respiratory disease and cystic fibrosis
• due to their thickening, stabilizing and gelling properties which can be
applied to wide range of foods such as jams, soups, sauces, meat,fish,
beverages, dairy products and confectionery
• they possess anti-inflammatory and detoxifying properties

24. Polysaccharide Food in which used Concentration required(%) Functionality

25. Curdlan
• Curdlan is a high molecular weight polysaccharide obtained from
Alcaligenes faecalis
• It is the improved version of the gums providing viscosity, rehydration,
gelling and texture-modification properties
Polysaccharide Food in which used Concentration required(%) Functionality

26. CONCLUSION
• The family of polysaccharides derived from microbes
plays a pivotal role in many industries and an
inevitable role in food processing industries.
• These microbial polysaccharides enhance the
quality, texture, mouth feel and flavor of the food as
thickeners, stabilizers, and texturizer and also as a
gelling agent.
• This ensures food processed packages available
today in the market has uplifted the expectations of
food quality from ready- to-eat meals to instant mix
as boon to the mankind in today’s era.

27. Reference
• Xanthan gum: production, recovery, and properties
F. GarcõÂa-Ochoaa,*, V.E. Santosa, J.A. Casasb, E. GoÂmeza
Departamento IngenierõÂa QuõÂmica, Facultad de Ciencias QuõÂmicas, Universidad Complutense de
Madrid,
E-28040 Madrid, Spain
Departamento de QuõÂmica±FõÂsica Aplicada, Facultad de Ciencias, Universidad AutoÂnoma de Madrid,
E-28049 Madrid, Spain
• Applications of Microbial Polysaccharides in Food Industry:Dr Ramalingam C*1, Jhanu Priya1, Shraddha
Mundra1
School of biosciences and technology, VIT University, Vellore, Tamilnadu, India.
Corresponding author’s E-mail: cramalingam@vit.ac.in