Water Analysis : To Study The Microbial Flora of Waste Water

AIM :- To study the microbial flora of wastewater.

Introduction :

Bacteria, fungus and actinomycetes are the microbial inhabitants of waste water:

Bacteria

Bacteria are the most numerous type of water organism. Every ml of water contains at least a million of these tiny one-celled organisms. There are many different species of bacteria, each with its own role in the environment. They are prokaryotes.

Fungi
Fungi come in many different species, sizes, and shapes in water. Some species appear as threadlike colonies, while others are one-celled yeasts. Fungi are generally quick to colonize larger pieces of organic matter and begin the decomposition process. Some fungi produce antibiotics including penicillin. They are eukaryotic, 

Actinomycetes
Actinomycetes are threadlike bacteria that look like fungi. While not as numerous as bacteria, they too perform vital roles in the water. Like the bacteria, they help decompose organic matter, releasing nutrients. They also produce antibiotics to fight diseases. Many of these same antibiotics are used to treat human diseases.

REQUIREMENTS:

1. Waste water sample
2. Nutrient agar media
3. Starch casein agar media
4. Potato dextrose  agar
5. Antibacterial agent
6. Antifungal agent
7. Petriplates

PROCEDURE:

For determining Bacterial Flora

1. Prepare nutrient agar plates aseptically.
2. Serially dilute  samples upto 10^-5 dilutions.
3. Inoculate from each dilution to separate nutrient agar plates by spread plate method.
4. Incubate  at 35C for 24-48 Hrs.
5. Observe the morphology of colonies and count the number of colonies
6. Do gram staining of respective colonies and observe its microscopic characteristics.

For determining Fungal Flora

1. Prepare potato dextrose agar plates containing antibacterial agent.
2. Serially dilute sample upto 10^-3 dilutions.
3. Inoculate from each dilution to separate potato dextrose agar plates by spread plate method.
4. Incubate at 20 Degree Celsius for 4-7 days.
5. Observe the morphology of colonies and count the number of colonies.

For determining Actinomycetal Flora

1. Prepare starch casein agar plates containing  antibacterial agent as well as anti fungal agent.
2. Serially dilute samples upto 10^-5.
3. Inoculate from each dilution to separate starch casein agar plates by spread plate method.
4. Incubate at 28 degree Celsius  for 15 days.
5. Mark the colonies grown in first 2 days as bacteria and colonies which grow after 2 days of incubation as actinomycetes.  
6. Observe the morphology of colonies and count the number of colonies.
7. Do gram staining of respective colonies and observe its microscopic characteristics.