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Heterotrophic bacteria importance:

- Lactobacillus is mainly used for making curd from the milk.

- Rhizobium is the nitrogen-fixing bacteria, generally present in the legume plants, where these plants fix the atmospheric nitrogen into ammonia, nitrates, and nitrites which can be used by plants for their growth and development.

- In the area of food processing microorganisms are useful, mainly they ferment the food and make it tasty.

- In the area of beverages also microorganisms are very useful, especially in the case of wine, the old fermented wine has more demand than fresh wine.

- Some of the microorganisms are useful for making medicines like antibiotics, for example penicillin is prepared from penicillium.

- Intestinal Microorganisms are very useful because they help full for synthesis of some essential nutrients, where vitamin b12 is synthesised by some intestinal bacteria .

So there are many economical uses of heterotrophic bacteria in human life.

hope this answers clear your doubt.

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