Bacteria found in the colon of man

Lactobacillus:
- Lactobacillus is a beneficial bacteria that is commonly found in the colon of humans.
- It is a type of lactic acid bacteria that plays a crucial role in maintaining the balance of the gut microbiota.
- Lactobacillus helps in the digestion of food, particularly carbohydrates, by producing enzymes that break down complex sugars into simpler forms.
- It also produces lactic acid, which helps create an acidic environment in the colon that inhibits the growth of harmful bacteria.
- Additionally, Lactobacillus helps in the absorption of nutrients, synthesizes vitamins, and strengthens the immune system.

Pseudomonads:
- Pseudomonads are a group of bacteria that are commonly found in various environments, including soil, water, and plants.
- While they can be present in the human colon, they are not considered beneficial bacteria.
- Some species of Pseudomonads are known to cause infections, particularly in individuals with weakened immune systems.
- In healthy individuals, the presence of Pseudomonads in the colon is generally low and does not contribute significantly to the overall gut microbiota.

Clostridium:
- Clostridium is a genus of bacteria that includes both beneficial and harmful species.
- Some species of Clostridium, such as Clostridium difficile, are known to cause severe infections, particularly in the colon.
- However, there are also beneficial species of Clostridium, such as Clostridium butyricum, which play a role in maintaining the health of the colon.
- Clostridium butyricum produces butyric acid, which is an important energy source for the cells lining the colon.
- It also helps in maintaining the pH balance in the colon and preventing the growth of harmful bacteria.

Escherichia coli:
- Escherichia coli, commonly known as E. coli, is a type of bacteria that is found in the intestines of humans and animals.
- While some strains of E. coli can cause infections and illnesses, there are also beneficial strains that are an essential part of the gut microbiota.
- Beneficial E. coli strains help in the digestion of food, produce vitamins, and compete with harmful bacteria for resources in the colon.
- However, it is important to note that not all strains of E. coli are beneficial, and some can cause serious health problems when present in high numbers.

In conclusion, among the given options, Lactobacillus is the beneficial bacteria commonly found in the colon of humans. Pseudomonads can be present, but they are not considered beneficial. Clostridium includes both harmful and beneficial species, while Escherichia coli can be beneficial or harmful depending on the strain.

A) Lactobacillus is correct answer.
It is useful in formation of curd.