Etiket Arşivleri: Pathogens

Antimicrobial Activity of Lactic Acid Bacteria on Pathogens in Foods ( Prof.Dr. Dilek HEPERKAN )

Antimicrobial activity of lactic acid
bacteria on pathogens in foods
Why succesful?
How succesful?

Prof.Dr. Dilek Heperkan

Istanbul Technical University,

Faculty of Chemical and Metallurgical
Engineering, Dept. of Food Engineering

Food Technology2014 21-23 July, Las Vegas

Microorganisms especially bacteria can be used for a number of beneficial purposes. Among them some are more prominent like Lactic acid bacteria (LAB) and bifidobacteria.

Lactic acid bacteria have been used as natural food-grade preservatives against a variety of undesirable microorganisms.

LAB has been used for production of fermented foods for many years. As a matter of fact fermented foods existed long before mankind discovered microorganisms.

During their activity in production of fermented foods their inhibitory potential on pathogenic bacteria have been recognised and they gained increasing interest in the scientific community.

Thus LAB has been used as a tool to produce antimicrobial compounds and to control undesirable microorganisms.


On the other hand, acute diarrhea due to the loss of normal intestinal microbiota, drug-resistant strains and chronic toxicity due to widespread use of antibiotics are well known negative effects of antibiotics.


The risks of toxic residues in foods, as well as contamination of soil and water due to the use of xenobiotics in food production chain are considered negatively by the public.

Lab producing a wide range of antimicrobial metabolites thus, the last two decades have seen pronounced advancements in using LAB and their metabolites for natural food preservation, as well as crop protection, and health protection.

Emerging Foodborne Pathogens ( Prof. Dr. İrfan EROL )


Prof. Dr. İrfan EROL, DVM, Ph.D.
Turkish Representative of World Vet. Assoc.

Department of Food Hygiene and Technology
School of Veterinary Medicine
Ankara University

Despite advances in hygiene, consumer knowledge, food treatment and processing, foodborne diseases mediated by pathogenic microorganisms or microbial toxins still represent a significant treat to public health worldwide.

Globally, the WHO has estimated that approximately 1.5 billion episodes of diarrhea and more than 3 million deaths occurred in children under 5 years of age, and a significant proportion of these results from consumption of food mainly food of animal origin with microbial pathogens and toxins

Emerging & Reemerging Zoonotic Diseases

60 % of the human pathogens are zoonotic

75 % of emerging zoonotic

Emerging Foodborne Pathogens


   those causing illnesses that have only recently appeared or been recognised in a population or that are well recognised but are rapidly increasing in incidence or geographic range

Emerging Foodborne Diseases

Appeared recently

Extended to new vehicles of transmission

Started to increase rapidly in incidence or geographic range

Been widespread for many years but only recently identified through new or increased knowledge or methods of identification and analysis of the disease agent

Emerging Foodborne Diseases

Pose a threat to all persons; no matter on age, sex, lifestyle or socio-economic status etc.

Feel pain and death

Economic impact

Emerging Foodborne Diseases
Major trends

Changes in environment (technology, climate, etc)

Mass production and globalisation of food supply

Economic development

International travel and trade

Changing character of the population

Breakdown in public health

Lifestyle changes

Microbial adaptation

Emerging Foodborne Pathogens





Emerging foodborne bacteria

Salmonella (multidrug resistant strain)

Campylobacter  jejuni

E. coli O157:H7

Listeria monocytogenes

S. aureus MRSA

Vibrio vulnificus

Yersinia enterocolitica

Arcobacter spp.

Mycobacterium paratuberculosis

Emerging foodborne viruses

Hepatit A and E


(Avian influenza, AI)

Emerging foodborne parasites

Cryptosporidium parvum

Cyclospora cayetanensis

Anisakis spp.

WHO Surveillance Programme for Control of Foodborne Infections and Intoxications in Europe  8th Report 1999-2000 Country Reports: Turkey

Salmonella serotype distribution in Turkey
(Erol et al., 2009)

S. Agona

S. Kentucky  Spices

S. Bredeney

Some Important Campylobacter Outbreaks in the World

Campylobacter jejuni

  Quinolone- and fluoroquinolone-resistant Campylobacter jejuni in the United States, 1982–2001

Campylobacter jejuni

Thermophilic Campylobacter spp. in turkey meat (n=270)
(Cakmak and Erol, 2009)

Thermophilic Camylobacter spp. 123 (45.5%)

C. jejuni 109 (40.3 %)

C. coli    11 (  4.0 %)

Not typed   3

Antibiotic resistance profile of C. jejuni isolates in turkey meat (Cakmak and Erol, 2009)

E. coli O157:H7 isolates found in fecal samples of cattle and sheep at slaughter in Turkey (Erol et al., 2008)

Toxin profiles of 11 E. coli O157:H7 isolates within the PFGE groups in cattle in Turkey (Erol et al., 2008)

Some Important Listeria outbreaks in the World

Contamination level of turkey meat with

  1. monocytogenes is 17.8 % (32/180)

(Ayaz and Erol 2008)

L. monocytogenes serotype distribution

  • 44.9 % 1/2a

  • 37.2 % 4b

  • 9.0 % 1/2b

  • 9.0 % 1/2c

Antibiotic resistance profiles of L. monocytogenes  in turkey meat (n:24) (Ayaz and Erol, 2008)

Occurrence of Cryptosporidium spp. oocysts in Turkey
(Kursun and Erol, 2003)

Antibiotic resistance

It’s a global concern of the antibiotic resistance of major foodborne pathogens such as;

Salmonella Typhimurium DT 104

Campylobacter  spp.

Listeria monocytogenes

  1. coli O157:H7

Staphylococcus aureus (MRSA)

Enterococcus (VRE)


  Risk management  Epidemiological   evaluation /

  Risk assessment


Control of Foodborne Disease

From farm to table approach

Implementation of GMP and HACCP

Public Health Approach

Public health system


Epidemiology for earlier diagnosis

Early response to outbreaks

Provide to disease patterns changing

Public health lab. support for rapid and accurate diagnosis

Rapid communication links

Communication to public

Education on prevention and/or detection

Factors contributing to the global incidence of foodborne disease

  • Poor sanitary conditions

  • Malnutrition

  • Changing demographics (increasing population of infants, elderly)

  • Inadequate public health infrastructure

  • Inadequate hygienic and technological conditions of food production

  • Inadequate cooking, reheating and storage conditions

  • Increasing tourism and international trade

  • Increasing animal movement and insufficient control of borders

  • Increasing international trade of animal and food

  • Inadequate legislation and official control system

  • Emerging/reemerging foodborne pathogens

  • Acquisition of virulence and antibiotic genes by nonpathogenic bacteria

  • Adaptation and enhanced survival of pathogens in food

  • Inadequate consumer education

outbreak in Turkey

Although there is a religious restriction on pork meat consumption, in January 2004 there was a big trichinellosis outbreak occurred by consuming çiğ köfte (raw ground meat ball-traditional food) in Izmir

542 people were affected and  samples were found to be contaminated with T. britovi

One World One Health (OWOH)

The medical and veterinary professions have a common interest in many diseases, primarily zoonotic diseases such as BSE, SARS and, most recently, Avian Influenza (H5N1), have highlighted the need for interprofessional collaboration not just locally and nationally, but on a global scale.

Improving animal and human health globally through collaboration among all the health sciences, especially between the veterinary and human medical professions to address critical needs.

Coliform Analysis in Water/ Membrane Filtration

General introduction:

Membrane  filtration  systems  are  especially  used  when  the  sample  like  drinking  water  or  fruit j uices   which  can  easily  pass through the filter  and  contain  really small  amount  of  microorganisms  less than   1 CFU/ ml.

About coliform bacteria and why do we do this test:  

Coliform   bacteria  are   present   in  the  environment  and  feces  of  all  warm-blooded  animals  and   humans.  Coliform  bacteria  are  unlikely  to  cause  illness.  However,  their  presence  in  drinking  water   indicates that  disease-causing  organisms  (pathogens)  could  be  in the  water  system.  Most  pathogens   that  can  contaminate  water  supplies  come  from  the  feces  of  humans  or  animals.  Testing  drinking   water   for   all   possible   pathogens   is   complex,   time-consuming,   and   expensive.   It   is   easy   and   inexpensive to test for coliform  bacteria.  If testing detects coliform  bacteria  in a water sample, water   services  search  for  the  source  of  contamination  and  restore  safe  drinking  water.  There  are  three   groups  of  coliform  bacteria.  Each  is  an  indicator  of  drinking  water  quality  and  each  has  a  different   level  of  risk. Total  coliform  is  a  large  collection  of  different  kinds  of  bacteria.  Fecal  coliform  are types   of  total  coliform  that  exist  in  feces.  E.  coli  is  a  subgroup  of  fecal  coliform.  Labs  test  drinking  water   samples for total  coliform.  If total  coliform  is  present, the  lab  also tests the sample for fecal  coliform   or E. coli, depending on the lab testing method.    Total  coliform  bacteria  are  common  in  the  environment  (soil  or  vegetation)  and  are  generally   harmless.  If  a  lab  detects  only  total  coliform  bacteria  in  drinking  water,  the  source  is  probably   environmental  and  fecal  contamination  is  unlikely.  However,  if  environmental  contamination  can   enter  the  system,  pathogens  could  get  in,  too.  It  is  important  to  find  and  resolve  the  source  of  the   contamination.     Fecal  coliform  bacteria  are  a  subgroup  of  total  coliform  bacteria.  They  exist  in  the  intestines  and   feces  of  people  and  animals.  The  presence  of  fecal  coliform  in  a  drinking  water  sample  often   indicates  recent fecal  contamination. That  means there  is  a  greater  risk that  pathogens  are  present.   E.  coli  is  a  subgroup  of  the  fecal  coliform  group.  Most  E.  coli  bacteria  are  harmless  and  exist  in  the   intestines  of   people  and  warm-blooded  animals.  However,  some  strains  can  cause   illness.  The   presence  of  E.  coli  in  a  drinking  water  sample  usually  indicates  recent  fecal  contamination.  That   means there is a greater risk that pathogens are present.    Note:  E.  coli  outbreaks  receive  a  lot  of  media   coverage.  A  specific  strain  of  E.  coli  bacteria   known as E. coli O157:H7 causes most of those   outbreaks.  When  a  drinking  water  sample  is   reported as  “E. coli  present,”  it does  not  mean   that   O157:H7   is   present.   However,   it   does   indicate  recent fecal  contamination.  Boiling  or   disinfecting       contaminated         drinking      water   destroys      all   forms      of   E.    coli,   including   O157:H7.

Recontamination Issues in the Food Processing Industry What, Where, and How Important are They? ( Dr. Paul A. Hall )

Producing Safe Food is Our Top Priority!

• Consumer protection and trust

– Consumers must be able to trust the brands they buy and the food they

– Food safety is absolutely critical to that trust

• Business survival/self-interest

– Our brands are our most important asset

– History is replete with brands and businesses being destroyed because

• Industry responsibility

– Moral obligation to produce food as safe as practical

– Industry pledge not to make safety a competitive issue eat of a lapse in food safety

Why is Food Safety our Top Priority?

• It is a cost of doing business

• The changing global food safety landscape demands more diligence, flexibility, and speed than ever before.

• The cost impact of not doing food safety right is higher than it’s ever been.

• The benefits of doing food safety right contributes directly to the bottom line – and not just in cost avoidance.

• Consumer and regulatory scrutiny are at an all time high.

• World class companies that win in the marketplace have world class food safety principles.

Causes of Foodborne Contamination

• Food Products can become contaminated via several routes:

– Naturally occurring (raw foods)

– Underprocessing/improper processing

– Recontamination/cross-contamination

• Pathogens

• Spoilage organisms

• Allergens

• Chemical contaminants

– Intentional contamination

• Economic adulteration (e.g melamine)

• Bioterrorism