This document discusses the importance of detecting microorganisms in food using biosensors as an alternative to traditional methods. It explains that biosensors work by combining a bioreceptor that interacts with the analyte of interest and a transducer that converts the bioreceptor/analyte interaction into a detectable signal. Specifically, some biosensors use bacteriophages that produce bioluminescence upon infecting target bacteria, allowing detection of pathogens like Listeria and Salmonella. While biosensors provide faster, easier detection than traditional methods, limitations include ensuring phages infect only the intended bacteria.

2. Why detection of micro
organisms in food is important?
“2.2 million people die annually due
to food and water borne illnesses,
and 1.9 millions among them are
children” -WHO

3. Why should We Use Biosensors as an
Alternative?
Less time consuming
Easy to use for on site
detection
No need of extensive
training

4. What is a Biosensor???
• A biosensor is an analytical
device, used for the
detection of an analyte,
that combines a biological
component with a
physicochemical detector.

5. How does a Biosensor Work?
Analyte
of
Interest
Bioreceptor Transducer Signal
Biosensor

6. Bacteriophages
• A bacteriophage is a virus that
infects and replicates within a
bacterium cell.
• Specific
• Attacks only to live cells
• Called as “Reporter-phage”

7. Bioluminescence
• Production of light by a
chemical reaction within a
living organism.
• Need Luciferase as the
enzyme
• And Luferin, photoprotein or
a long chain aldehyde as
substrate.

8. Reaction of Bioluminescence

9. Simply…

10. Applications in Food Industry
• A511::lux AB recombinant phage
is used to identify Listeria
bacterium in Spikked ricotta
cheese, chocolate pudding etc.
• A511::lux AB is used to check the
quality of minced meat and soft
cheese.
• P22::lux AB is used to identify
Salmonella Spp.
• ( ex:- in eggs )

11. Limitations
• Presence of specific phage
inhibition antiviral bacterial
immunity system.
• Selecting specific phages.

12. Future..
• You can check your
food at home..