Source, Structure and Uses Vitamin A1 and A2

Vitamin A1 (Retinol)

Source:

• Animal-based: Liver, fish oil, eggs, dairy products (milk, cheese, butter).
• Plant-based (provitamin A): Carrots, spinach, sweet potatoes, and other fruits and vegetables containing beta-carotene, which is converted into vitamin A in the body.

Structure:

• Retinol (Vitamin A1) has a molecular structure consisting of a β-ionone ring linked to an isoprenoid chain. Its chemical formula is C20H30O.

  
  

Uses:

• Vision: Retinol is essential for the production of rhodopsin, a pigment in the retina, necessary for low-light and color vision.
• Skin health: Promotes healthy skin, aids in wound healing, and is used in dermatology to treat acne and wrinkles (in its derivative form, retinoids).
• Immune function: Supports the immune system, promoting the proper functioning of mucous barriers in the eyes, lungs, and intestines.
• Growth and development: Vital for cell growth, differentiation, and organ development, especially during fetal development.

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Vitamin A2 (3,4-Didehydroretinol)

Source:

• Freshwater fish: Vitamin A2 is primarily found in freshwater fish like eels. It is less common in land animals and plants.

Structure:

• Vitamin A2 is similar to retinol but has a double bond between carbons 3 and 4 in the β-ionone ring, making it slightly different in structure. Its chemical formula is C20H28O.

  

Uses:

• Vision: Like Vitamin A1, Vitamin A2 plays a role in vision, particularly in certain species of fish, which rely on it for visual processes in different light environments.
• Although Vitamin A2 is biologically active, it is generally less potent than Vitamin A1 and is less commonly used in humans.