Cultivation of Microbes(just as animals and plants)

By Muhammad Haider Ali

Cultivation of Microbes(just as animals and plants)

Growth and Production of Microbes

We are living in a modern age of science and technology where the scientists invented a lot of things for human facilitation. Some are really helpful for example uncountable medicines, machines and technology. Computer and information technology aids almost all fields of science to improve in a better way and with hundreds time greater speed as compared to previous. But when we compared developing countries, like Pakistan, technologies and inventions with developed countries we realize that we need improvements, studies and research in the field of science and technology. Most of the people think that its only duty of government, although government should take care of it to compete with the world but its individual duty of all citizens and education cells like schools, colleges, universities and research institutes to produce quality education and students whom can bring improvements in future.

You may have listened about the growth of farm animals, plants, poultry and wild animals etc. But in this article, I am going to talk about growth and production of microorganisms. The word “microorganisms” used for those minute creatures which can only be seen under the microscope. The living organisms can’t be seen by naked eye. In some literature, they defined by size which is <0.1mm. These includes bacteria, viruses, fungi, some protozoan and some parasites. The interesting fact is that they present at every place in all type of environments even in below freezing temperature and above boiling temperature. They have many beneficial aspects like complete natural cycles, decompose waste materials, fermentation, produce different medicines etc. At the same time, they also cause diseases in human, plants and animals. They spoil our food materials. The scientific study of these too much small living organisms is termed as “Microbiology”.

If we talk about history, Antoni Van Leeuwenhoek (1673) was a scientist who probably the first person to observe living cells with a simple microscope, ground his own lenses and described what we know today as bacteria. But the Golden Age of Microbiology starts with Pasteur’s work who practically prove the existence of microbes. Before his work people believe on spontaneous generation theory which says living things arise from nonliving things by vital force. Many scientists worked on it but Pasteur put an end to this theory.

There is another advanced and applied term “Biotechnology” which deals with their use for human welfare. This starts from Edward Jenner’s work of inventing the first vaccine for smallpox. Then different scientists developed vaccines from viruses against different diseases like polio. But a wonderful invention was the penicillin by Alexander Fleming from fungi. This was first naturally secreted chemical effective against wide range of bacterial infections and still has applications in the field of medicine and antibiotics. Then different antibiotics and hormones were produced by fungi as well bacteria. For all these productions we should have an appropriate population of these living organisms or their growth and reproduction just like we need the cow for milk production and fruit trees for fruit production. But the growth requirements and procedure of microbes are somewhat different than animals and plants.

Bacterial Growth:
Just like all other living organisms, bacteria also have some basic requirements for their life, growth and reproduction. When we grow them in a laboratory, all physical factors are provided by special growth chambers and incubators. While basic nutrients (organic and inorganic) provided by food called culture media like nutrient agar, nutrient broth, blood agar and chocolate agar (just like bread, rice, fruits and vegetables for human). The media for their growth (food of microbes) is available in the market. You can also prepare media in your lab if you have knowledge and experience.

Take the nutrition media in a test tube or Petri plate and inoculate it with bacteria sample and place in incubator or growth chamber at 370C. They will start to reproduce in logarithmic order and increase in millions just in hours. After their production we can use them:

For bacterial studies

  • For classification and taxonomy studies
  • For research purposes
  • For bioremediation
  • For fermentation e.g. Yogurt
  • For antimicrobial resistant analysis of antibiotics
  • For growing bacteriophages (viruses)
  • For antibiotics production
  • For the production of different hormones used in food, textile and medicine industry etc.

Fungal Growth:
Fungi, a wide range of living organisms some can be seen by naked eye e.g. mushrooms (edible fungi) and mostly seen by microscope (pathogenic fungi). They are fomenters and decomposers so play important role in nature but some cause different diseases in human, plants and animals. Like bacteria fungi also grow and reproduce in labs. But its requirements and conditions are different than bacteria. Fungi require special media called Sabouraud’s agar for growth in lab and high level of humidity than bacteria. It requires 250C temperature for growth. Cultivated fungi used:

For study and research purposes

  • For dye (colors used in textile industry) production
  • For bioremediation and reclamation
  • For enzymes production
  • In production of cheese, bread and fizzy drinks
  • For biological control of pests and other microbes
  • For fermentation (yeast) and decomposition
  • For the production of antibiotics (best example penicillin) etc.

Viral Growth:
Viruses called as non-cellular infectious particles that can only reproduce within the living cells and out of living cells they show characteristics of nonliving things. Unlike bacteria and fungi, most of the viruses are pathogenic in nature and cause different diseases in man, animals and plants. As by definition, they only reproduce within the living cells by using host cell machinery, their culture/growth require special techniques. They can be cultured in the lab by using living systems.  Mostly we use lab animals e.g. rats, white mice and rabbits etc. Viruses simply inject by injection in animals where it starts reproduction. Another method is bird’s egg inoculation in which 10-11 days old incubated the fertile egg in is inoculated by a viral sample (using injection). As egg has living embryo so virus starts its reproduction in the egg and after 2-3 days we can collect viral population from the fluid of egg. In modern labs, cell culture and tissue culture also used for viral growth but it is costly than old methods. Viruses cultivate for following purposes:

Isolation and identification in clinical specimens

  • For study and research
  • For using in biological controlFor vaccines production
  • Used as vector in genetic engineering techniques
  • Used to transfer some genes in gene therapy
  • Used to produce cross protection in plants
  • Used to produce colors in flowers (e.g. in Tulip) etc.

Warning:

Be careful while playing with microbes, they can be pathogenic and cause serious diseases. They can change their genetic makeup. Always take them as pathogens and use authentic lab and equipment for cultivation of any microorganism because it not only risks for your health but also for society.

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