SCP_Environmental Biotechnology Application.pptx

SCP_Environmental Biotechnology Application.pptx

• 1.
  Single Cell Protein Generationof Industrial Microbial Products
• 2.
  Introduction • Single cellprotein refers to a crude, refined or edible protein extracted from pure microbial culture as dead or dried cell biomass. They are also called as ‘Microbial protein’. • SCP can be used as protein supplements for both humans and animals and is classified as food grade and feed grade respectively. • Algae, yeast, fungi, bacteria have high protein content in their biomass. • SCP has advantages over conventional protein sources because they can be produced throughout the year regardless of the weather and microorganisms have rapid growth than plants and animals.
• 3.
  Nutritional Value ofSCP • Composition of microbial cells include proteins, amino acids, nucleic acids, fats, vitamins and minerals. Composition Fungi Algae Yeast Bacteria Protein 30-40% 40-60% 45-55% 50-65% Fats 9-14% 8-10% 5-10% 3-7% Nucleic acids 7-10% 3-8% 6-12% 8-12%
• 4.
  Basic steps ofSCP production 1. Raw materials/substrates 2. Selection of suitable strain 3. Fermentation 4. Harvesting 5. Post harvest treatment 6. Processing of SCP for food
• 5.
  1. Raw materials A.Hydrocarbons • Gaseous • Liquid B. Alcohols • Methanol • Ethanol C. Waste products • Wood/ Plant waste- Cellulose containing materials • Starch waste- Rice, potato, cassava etc. • Dairy waste- Whey • Waste from chemical industry- Carbon sources • Miscellaneous Substrates- Molasses
• 6.
  A. Hydrocarbons 1. GaseousHydrocarbon • Methane is used as a source of SCP as it is dominant in natural gas. Propane and butane are also used. • Different microorganisms are mixed together and grow on methane which provides high yield. • Bacteria utilize methane and produce methanol. Hyphomicrobium utilizes the produced methanol. Advantage: • No residual hydrocarbons in newly produced SCP. Disadvantage: • Highly inflammable 2. Liquid Hydrocarbons • Crude petroleum is used as source of SCP but this substrates are now less used.
• 7.
  B. Alcohols Methanol issuitable as a source because of • High water solubility • Explosion hazard of methanol is minimized comparing to methane-oxygen mixtures, • Readily available; • Easy purification process avoid of using toxic compounds. • Requires less oxygen Ethanol is mostly used as a substrate of yeast. Advantage: Highly miscible with water. Storage and transportation are safer Non-toxic and can be easily handled Requires less oxygen • Releases less heat. Disadvantage • Expensive
• 8.
  2. Selection ofsuitable strain • Properties required for microorganisms – 1. Absence of pathogenicity and toxicity: The organisms should not contain or produce toxic or carcinogenic materials. 2. Protein quality and content: The amount of protein should be high as per requirement. 3. Digestibility and organoleptic qualities: The organism should be digestible as well as should possess acceptable taste and aroma. 4. Growth rate: It must grow rapidly in a cheap, easily available medium. 5. Adaptability to unusual environmental conditions: Strain should grow at low pH or at high temperature.
• 9.
  List of microorganisms •Algae- • Spirulina sp. • Chlorella pyrenoidosa • Chondrus crispus • Yeast- • Saccharomyces cerevisiae • Candida utilis • Candida tropicalis
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  3. Fermentation • Itcan be carried out in a fermenter which is equipped with aerator, thermostat, pH, or in the trenches or ponds. • Microbes are cultured in fed batch culture. • Controlled conditions for different SCPs- Name of organisms Temperature (0 C) pH Yeast 25-26 4-4.4 Fungi 25-30 5-6 Algae 25 8-10 Bacteria 35-45 5-7
• 11.
  Harvesting and Postharvesting 4. Harvesting • When the colonies are fully developed they are ready for harvesting. • The bulk of cells are removed from the fermenter by decantation. 5. Post harvesting: After harvesting the cells they go through separation, washing and drying for purification. • Separation: Yeast and bacterial cells are recovered by centrifugation, flocculation, floatation. Filamentous organisms (fungi) are recovered by filtration. • Washing: Separated biomass are washed. • Drying: Water is removed as much as possible before final drying.
• 12.
  6. Processing ofSCP 1. Cell wall degradation of SCP products: • Mechanical method- Crushing, crumbling, grinding, Pressure homogenization • Chemical method – Enzyme (nuclease), salt (NaCl, sodium dodecyl sulfate etc.) • Physical method – Freeze-thaw, osmotic shock, heating and drying. 2. Nucleic acid removal from SCP: Higher level of nucleic acid is the reason of higher level of uric acid in blood plasma which may result in kidney stones and gout. Amount of nucleic acid carried by different SCP- algae, 4-6%; yeasts, 6-11%; bacteria, up to 16%. • Removal process: a) Growth and cell physiology method b) Extraction with chemicals c) Use of pancreatic juice d) Activation of endogenous RNA.
• 13.
  2. Nucleic acidremoval process a) Growth and cell physiology method: RNA content of cell depends on growth rate of microbes. By reducing growth rate, level of nucleic acid can be reduced but higher growth is one of the requirements of reducing costs in SCP. b) Extraction with chemicals: Bases such as NaOH or KOH and hot 10% NaCl can be used to hydrolyze and extraction of RNA. c) Use of pancreatic juice: RNAase from bovine pancreatic juice is used to hydrolyze yeast RNA at 80°C as at this temperature the cells are more permeable. d) Activation of endogenous RNA: The RNAase of the organism itself can be used to reduce the RNA content of yeasts.
• 14.
  Applications of SCP 1.As protein Supplemented food: • Source of vitamins, amino acids, minerals, crude fibers etc. along with proteins. • Useful for undernourished children. 2. As healthy food: • Controls obesity • Provides instant energy 3. As therapeutic and natural medicines: • Reduce body weight, cholesterol, stress • Lower body sugar level in diabetes • Healthy eyes, skin and due to beta carotene • Increase lactation
• 15.
  Applications… 4. In cosmetics: Maintainhealthy hair due to the presence of vitamin A and B Herbal beauty products Bioplastics and herbal face cream • Has potential of replacing coal tar dye based cosmetics 5. As poultry and cattle feeds: Convenient source of protein and other nutrients. • Used to feed cattle, fishes etc.