conventional test methods are simple, easily resilient, and usually inexpensive.
Mostly, conventional methods are very sensitive and laborious and may require
several days. Products that are minimally processed have a naturally short shelf life,
which prevents the use of many of these conventional methods. Therefore, extensive
research work has been executed to reduce assay time and reduce the amount of
manual labor by automating methods through the use of interdisciplinary approaches
to detect microorganisms and their toxins. It is against this background the detection
and monitoring of environmental pollutants are classified into the following groups:
Molecular and various sensor-based methods. These methods of detection can be
used to effectively combat environmental components and biological tissues. This
chapter presents the monitoring technologies for pathogen agents and their toxins
and to discuss the advantages, disadvantages, and various characteristics of those
methods. It gives an overview of environmental analytical methodologies reliable
for public safety and environmental surveillance.
9.1.1 Pathogen and Its Toxins
A pathogen and its toxins that are biological agents cause disease, disability, or
seizure to its host. The term is most often used for describing an infectious agent
such as a virus, bacterium, protozoa, prion, fungus, or other microorganisms that
disrupt the normal physiology of multicellular animals or plants.
9.1.2 Bacteria
Bacteria are microscopic single-celled organisms that flourish in different type of
environments. Most catastrophic diseases such as pneumonia, food-borne illness,
blood stream infection (sepsis), and sexually transmitted diseases like gonorrhea are
caused by bacteria. Pathogenic bacteria, like Streptococcus and Pseudomonas, cause
globally important diseases, such as pneumonia, and Shigella, Campylobacter, and
Salmonella cause food-borne illnesses. Hans Christian Gram, a microbiologist,
categorizes bacteria into two groups: (a) Gram-positive and (b) Gram-negative
bacteria, and the difference between them is in the cell structure of their wall. Nearly
95% of pathogenic bacteria are Gram-negative bacteria, and the rest are Grampositive bacteria.
9.1.3 Virus
A virus is a small infectious agent that cannot replicate itself. Viruses have either
DNA or RNA as genetic material. It can infect all types of life forms, from animals
and plants to microorganisms, including bacteria and archaea and directly instruct
the cell machinery to reproduce more and more virus cells.
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S. Purwar and S. Srivastava
Mostly, conventional methods are very sensitive and laborious and may require
several days. Products that are minimally processed have a naturally short shelf life,
which prevents the use of many of these conventional methods. Therefore, extensive
research work has been executed to reduce assay time and reduce the amount of
manual labor by automating methods through the use of interdisciplinary approaches
to detect microorganisms and their toxins. It is against this background the detection
and monitoring of environmental pollutants are classified into the following groups:
Molecular and various sensor-based methods. These methods of detection can be
used to effectively combat environmental components and biological tissues. This
chapter presents the monitoring technologies for pathogen agents and their toxins
and to discuss the advantages, disadvantages, and various characteristics of those
methods. It gives an overview of environmental analytical methodologies reliable
for public safety and environmental surveillance.
9.1.1 Pathogen and Its Toxins
A pathogen and its toxins that are biological agents cause disease, disability, or
seizure to its host. The term is most often used for describing an infectious agent
such as a virus, bacterium, protozoa, prion, fungus, or other microorganisms that
disrupt the normal physiology of multicellular animals or plants.
9.1.2 Bacteria
Bacteria are microscopic single-celled organisms that flourish in different type of
environments. Most catastrophic diseases such as pneumonia, food-borne illness,
blood stream infection (sepsis), and sexually transmitted diseases like gonorrhea are
caused by bacteria. Pathogenic bacteria, like Streptococcus and Pseudomonas, cause
globally important diseases, such as pneumonia, and Shigella, Campylobacter, and
Salmonella cause food-borne illnesses. Hans Christian Gram, a microbiologist,
categorizes bacteria into two groups: (a) Gram-positive and (b) Gram-negative
bacteria, and the difference between them is in the cell structure of their wall. Nearly
95% of pathogenic bacteria are Gram-negative bacteria, and the rest are Grampositive bacteria.
9.1.3 Virus
A virus is a small infectious agent that cannot replicate itself. Viruses have either
DNA or RNA as genetic material. It can infect all types of life forms, from animals
and plants to microorganisms, including bacteria and archaea and directly instruct
the cell machinery to reproduce more and more virus cells.
186
S. Purwar and S. Srivastava