Fruits and vegetables are rich in a variety of bioactive compounds and nutrients that are essential for human health. The chemical composition of fruits and vegetables can vary depending on the type, variety, and growing conditions, but generally, they contain the following components:

1. Water Content Water is the major constituent of fruits and vegetables, typically making up 70% to 95% of their total weight. Examples: Cucumbers (95% water), Tomatoes (94% water), Apples (85% water).
   • Function: Water plays an essential role in maintaining hydration, supporting biochemical reactions, and contributing to texture and juiciness.

2. Carbohydrates: Carbohydrates are the primary source of energy in fruits and vegetables, and they are mainly found as sugars and dietary fiber.
   • Sugars: Includes glucose, fructose, and sucrose.
   • Dietary Fiber: Composed of cellulose, hemicellulose, and pectin. Examples: Bananas are rich in sugars (fructose, glucose), while apples and broccoli are rich in fiber.
   • Function: Carbohydrates provide energy, while fiber aids in digestion and supports gut health.

3. Proteins: Proteins are present in smaller quantities compared to carbohydrates, but they play a crucial role in the growth and repair of tissues.
   • Amino Acids: Fruits and vegetables contain various essential and non-essential amino acids. Examples: Peas, spinach, and soybeans have relatively high protein content.
   • Function: Proteins contribute to muscle repair, enzyme functions, and overall growth.

4. Fats (Lipids): Lipids are found in small amounts, mainly in the form of fatty acids, phospholipids, and triglycerides. Examples: Avocados and olives are examples of fruits that contain healthy fats like oleic acid. Function: Lipids provide energy, support cell membrane structure, and help in the absorption of fat-soluble vitamins (A, D, E, K).

5. Vitamins Fruits and vegetables are excellent sources of essential vitamins, which are crucial for various metabolic processes. The main vitamins include:

• • Vitamin C (Ascorbic Acid): Examples: Citrus fruits (oranges, lemons), strawberries, bell peppers, broccoli. Function: Vitamin C acts as an antioxidant, promotes wound healing, and boosts the immune system.
  • Vitamin A (Beta-carotene): Examples: Carrots, sweet potatoes, spinach, kale. Function: Essential for vision, immune function, and skin health.
  • Vitamin K: Examples: Leafy greens like kale, spinach, and cabbage. Function: Important for blood clotting and bone health.
  • B-Vitamins (B1, B2, B3, B5, B6, B7, B9, B12): Examples: Leafy greens, peas, avocados. Function: Vital for energy metabolism, nerve function, and DNA synthesis.
  • Vitamin E (Tocopherol): Examples: Nuts, seeds, spinach, broccoli. Function: Acts as an antioxidant and protects cells from oxidative stress.

6. Minerals Fruits and vegetables are rich in various minerals that are crucial for maintaining bodily functions:

• • Potassium: Examples: Bananas, oranges, potatoes, tomatoes. Function: Helps maintain fluid balance, nerve transmission, and muscle function.
  • Calcium: Examples: Kale, collard greens, broccoli. Function: Essential for bone health, muscle function, and nerve signaling.
  • Magnesium: Examples: Spinach, pumpkin seeds, avocados. Function: Involved in muscle function, nerve function, and energy production.
  • Iron: Examples: Spinach, lentils, beans, peas Function: Crucial for oxygen transport in the blood (hemoglobin).
  • Phosphorus: Examples: Leafy greens, potatoes, peas. Function: Important for bone and tooth health, energy production.

7. Organic Acids

• Citric acid: Found mainly in citrus fruits like lemons and oranges.
• Malic acid: Present in apples, pears, and cherries.
• Tartaric acid: Found in grapes and tamarinds.
• Function: Organic acids contribute to the sour taste of fruits, aid in the preservation of food, and have antioxidant properties.

8. Antioxidants

Fruits and vegetables contain several bioactive compounds that have antioxidant properties, including:

• Flavonoids: Found in berries, apples, onions, and grapes.
• Phenolic Compounds: Present in tomatoes, potatoes, and apples.
• Lycopene: Found in tomatoes, watermelon, and pink grapefruit.
• Anthocyanins: Present in berries, cherries, and purple cabbage.
• Function: These compounds help protect cells from oxidative damage, which can reduce the risk of chronic diseases like heart disease, cancer, and diabetes.

9. Phytochemicals

• Carotenoids: Found in carrots, sweet potatoes, and dark leafy greens (e.g., kale, spinach). They include alpha-carotene, beta-carotene, lutein, and zeaxanthin.
• Glucosinolates: Found in cruciferous vegetables like broccoli, cabbage, and cauliflower. They have cancer-protective properties.
• Saponins: Present in beans and legumes; they have anti-inflammatory properties.
• Function: These compounds have a variety of health-promoting effects, including anti-inflammatory, anti-cancer, and cardiovascular health benefits.

10. Water-Soluble and Fat-Soluble Compounds

• Water-Soluble Compounds: Mainly found in fruits like citrus (Vitamin C, flavonoids, organic acids) and are involved in hydration and antioxidant defense.
• Fat-Soluble Compounds: Found in vegetables like spinach and carrots (Vitamin A, Vitamin K, and carotenoids) and are important for vision, skin, and immune health.

11. Enzymes

• Many fruits, such as pineapples and papayas, contain proteolytic enzymes like bromelain and papain, which help break down proteins and are used in food tenderizing. Function: Enzymes aid in digestion and may have anti-inflammatory properties.

Summary of Chemical Composition (Example: Apple)