Pleomorphism of Lysosomes

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  Pleomorphism of Lysosomes Lysosomes show pleomorphism, which means they occur in many different forms according to their functional state. They are not always identical in shape, size, or contents. Their appearance changes depending on whether they are newly formed, involved in digestion, or storing undigested waste materials.  Lysosomes are membrane-bound organelles containing hydrolytic enzymes. These enzymes digest proteins, lipids, carbohydrates, nucleic acids, and other cellular materials. Since lysosomes perform different digestive functions inside the cell, they appear in different structural forms. This property is called pleomorphism.  The main pleomorphic forms of lysosomes are primary lysosomes, secondary lysosomes, autophagic vacuoles, and residual bodies. Primary lysosomes are newly formed lysosomes produced by the Golgi apparatus. They contain inactive hydrolytic enzymes and have not yet taken part in digestion. They are small, spherical vesicles surround...
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Fungi in Production of Organic Acid

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 Fungi in Production of Organic Acids

Biochemical activities of several fungi are utilized in the commercial production of organic acids.

1. Citric acid: It is produced by fermenting sucrose and molasses by Aspergillus niger and A. wentii. Citric acid is used in soft drinks and other foods and medicinal preparations. It is a superior sequestering agent and is used in the manufacture of ink, dyeing, electroplating and leather tanning.

2. Itaconic acid: It is produced by fermentation of sugars by Aspergillus itaconicum and A. terreus. It is widely used in the manufacture of alkyl resins, synthetic fibres and plasticizers.

3. Gluconic acid: It is produced by fermenting sugars by Aspergillus niger and Penicillium purpurogenum. It is used in pharmaceutical, food, textile, leather and photographic industries.

4. Kojic acid: It is produced by fermentation of sugars by Aspergillus oryzae. It possesses insecticidal and antibiotic properties and is used in the preparation of pyridines, ethers, esters, azodyes, etc.

5. Gallic acid: It is synthesized by the hydrolysis of gallotannin present in gall nuts by Penicillium glaucum and Aspergillus gallomyces. It is used in the manufacture of inks and dyes.

6. Fumaric acid: It is obtained by fermentation of sugars by Rhizopus stolonifer. It is used in the manufacture of alkyl resins and wetting agents.

7. Others: Besides, several species of Mucor and Rhizopus are used in the production of lactic, oxalic and succinic acids.



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