anticarcinogenic properties of probiotics

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Anticarcinogenic properties of probiotics

• Debika Roy
• Department of Dairy Microbiology
• Faculty of Dairy Technology
• WBUAFS

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understanding the definitions

• Prebiotic - (greek - before life) a substance
  (usually an oligosaccharide) that cannot be
  digested but does promote the growth of
  beneficial bacteria or probiotics.
• Probiotic - (for life) a substance that contains
  microorganisms or bacteria that are beneficial to
  the host organism.
• Symbiotic - (plus life) a substance containing
  both a prebiotic and probiotic.

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What are Probiotics

• Probiotic organisms are live microorganisms
  thought to be beneficial to the host organism.
  According to the currently adopted definition by
  FAO/WHO, probiotics are "Live microorganisms
  which when administered in adequate amounts
  confer a health benefit on the host". Lactic acid
  bacteria (LAB) and bifidobacteria are the most
  common types of microbes used as probiotics but
  certain yeasts and bacilli may also be used.

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Probiotics microorganisms

• Probiotics consist specific microbial cultures
  and/ or ingredients that stimulate gut micro
  flora capable of modifying the gastrointestinal
  environment which keeps the host healthy
• Lactic acid producing bacteria
• Lactobacilli and Bifidobacterium
• Yeast
• Others
• Commercially available products may contain pure
  and combined cultures of
• Lactobacillus
• Bifidobacterium
• Streptococcus
• Pedicococcus
• Aspergillus
• Bacillus

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Probiotics health benefits
Elimination of lactose intolerance Anti-diarrheal
Immunomodulatory Antidiabetic Anticarcinogenic
Hypocholesterolemic Antihypertensive
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Probiotics and Cancer

• Colorectal cancer represents a major public
  health problem accounting for over 1 million
  cases and about half a million deaths worldwide .
  Survival from colon cancer at 5 years has been
  found to vary demographically and estimated to be
  65 in North America, 54 in Western Europe, 34
  in Eastern Europe, and 30 in India.
• Although chemotherapy and radiotherapy have been
  applied as the surgical adjuvant treatments of
  colon cancer, they vary in success rates for
  local recurrence, disease-free survival, and
  overall survival . In addition, these treatments
  may present some side effects such as an
  increased risk for infections, hair loss,
  fatigue, vomiting, diarrhea, and bloody stools.

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Probiotics and Cancer

• Diet interventions and natural bioactive
  supplements have now been extensively studied to
  reduce the risks of colon cancer, as a cause of
  prevention instead of cure. Postulated mechanisms
  include reduction in the activity of several
  cancer causing bacteria, desmutagenic and
  anticarcinogenic properties.
• Prebiotics, being indigestible, have been
  associated with improved bowel functions and
  metabolisms of the distal colon, including a
  reduced risk of colon cancer.

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Probiotics and Cancer

• Enzymes (Glycosidase, B- glucuronidase ,
  azoreductase , and nitroreductase ) of the
  intestinal flora convert the precarcinogens to
  active carcinogens
• Probiotics reduce
• Faecal concentrations of enzymes
• Secondary bile salts
• Reduce absorption of harmful mutagens that may
  contribute to colon carcinogenesis.

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Some proposed mechanisms

• Several mechanisms have been proposed as to how
  lactic acid bacteria may inhibit colon cancer
• Enhancing the hosts immune response
• Altering the metabolic activity of the
  intestinal microflora
• Binding and degrading carcinogens
• Producing antimutagenic compounds
• Altering the physiochemical conditions in the
  colon

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Research on cancer still
experimental
The strongest evidence for the anti-cancer
effects of probiotics comes from animal studies
evidence from human studies (epidemiology and
experimental) is still limited. An important goal
for the future should be carefully designed human
clinical trials to corroborate the wealth of
experimental studies.
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