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TRANSCRIPT
Marine Bacteria as Probiotics and Their
Applications in Aquaculture
Presented by:
Akram Najafi
History
• It is a composite of the Latin preposition pro ("for") and the
Greek adjective βιωτικός (biotic), the latter deriving from the
noun βίος (bios, "life").
• Introduction of the concept is generally attributed to Nobel
Prize recipient Elie Matchnikoff.
In 1907, he suggested that "the dependence
of the intestinal microbes on the food makes
it possible to adopt measures to modify the
flora in our bodies and to replace the harmful
microbes by useful microbes.
• The World Health Organization’s 2001 definition of probiotics
is "live microorganisms which, when administered in adequate
amounts, confer a health benefit on the host.
Types of bacteria in body
- 10 times of the whole body cells (10 14)
- 1.5 kg of whole body weight
- 35 to 50 % colon
- 60 % of fecal mass
- 300 to 1000 different species
- Useful bacteria = 85 % of whole intestine microorganisms
Probiotic bacteria may colonise the upper part of the intestine to
avoid the adhering of pathogens to the intestinal tract and may
help in digestion.
Bacteria
• Decrease of potentially pathogenic gastro-intestinal
microorganisms
• Reduction of lactose resistance by LAB
• Reduction of gastro-intestinal discomfort
• Strengthening of the immune system
• Improvement of the skin's function
• Nutrition absorption, vitamins, inorganic materials.
• Strengthening of the resistance to cedar pollen allergens
• Reduction of flatulence and bloating;
• The protection of DNA
• Protection of proteins and lipids oxidative damage
• Anticancer
Benefits of probiotics
The most important bacteria in probiotics
Bifidobacterium longum subsp. infantis
Saccharomyces boulardiiLactobacillus sp.
Two forms of consuming
• Powder
• Syrup
• Capsule
Probiotics in Iran
10 9 CFU
6 * 10 9 CFU1.5 * 10 10 CFU
Enriched foods
Milk Yakult
Kefir
Breakfast Cereal
Snack bar
Yogurt Kimchi
Chees Sauerkraut
Pickled vegetables
Prebiotic & Synbiotics
• Prebiotics are carbohydrates that cannot be digested by the human
body. They are food for probiotics. A prebiotic is a fiber such as
fructose oligosaccharide, galactose oligosaccharide, etc., and is
consumed that is intended to stimulate the microflora which is
already present in the large intestine.
• Synbiotics refer to nutritional supplements combining probiotics
and prebiotics in a form of synergism.
Good sources of prebiotics
AsparagusJerusalem artichokes Oatmeal
Aquaculture
• Aquaculture is the farming of aquatic
organisms such as fish, crustaceans,
molluscs, aquatic plants.
• Major constraints on successful
aquaculture production:
- bacterial & viral diseases & high
mortality
• Disinfection of the hatchery and rearing
facilities can cause loss in a stable
microbial balance through proliferation
of opportunistic bacteria that enter into
the system and thereby limit the natural
biological control of opportunistic
pathogens.
• New strategies: ban on antibiotic and growth promoters in
aquaculture practices.
• Developing novel dietary supplement strategies to produce health
and growth-promoting compounds in aquaculture as:
- Prebiotics
- Probiotics
- Symbiotics
- Phytobiotics
• Bacillus, Lactobacillus, Lactococcus, Enterococcus, Clostridium,
Leuconostoc, Pseudomonas, Vibrio, Aeromonas, Shewanella, yeasts
bacteriophages, unicellular algae have been studied for use as
probiotics in aquaculture.
• By manipulation of the gut/intestinal microbial environment, the
survival and health of the organism in intensive rearing system
could be improved.
Live microbial adjunct which has a
beneficial effect on the host by modifying
the host associated or ambient microbial
community, by ensuring improved use of
the feed or enhancing its nutritional value,
by enhancing the host response towards
disease, or by improving the quality of its
ambient environment.
Definition of Probiotics in aquaculture
Certain beneficial characteristics need to be present for a
microorganism to be a probiotic in aquaculture:
- They must isolate from the environment where the probiotic will be
applied and avoid risk of introduction of all autochthonous organisms to
the system.
- Show beneficial effect
- Be nontoxic or nonpathogenic to the host and to other living
organisms in the system such as phytoplankton.
Currently, a number of probiotics are
commercially available and have been
introduced in molluscan, shellfish, and fish as
feed additives and also in culture waters
Mechanism of probiotics
- Antagonism to pathogens
- Competitive exclusion for adhesion sites
- Ability to produce organic acids, hydrogen peroxide
- Metabolites like vitamins, enzymes, lysozyme, antimicrobials,
siderophores
- Modulation of host immunity and physiology
Probiotics as Immune Stimulants
Clostridium butyricum bacteria given
orally to rainbow trout have shown
increased phagocytic activity of
leukocytes & enhanced the resistance of
fish to Vibriosis.
Addition of Bacillus species (strain S11) to
tiger shrimp provided disease protection by
activating both humoral and cellular
immune defenses
Use of Lactobacillus rhamnosus or their cell
wall components as prophylactic factor to
low stress in Oreochromis niloticus has been
reported
Antiviral effects
Recently, it has been found that probiotics
have beneficial effects against viral infections
such as iridovirus in Epinephelus coioides.
It has been reported that strains of Vibrio sp.,
Aeromonas sp., Pseudomonas sp., and groups
of coryneforms isolated from freshwater
salmon hatcheries showed antiviral activity
(more than 50% plaque reduction) against
infectious hematopoietic necrosis virus
(IHNV)