Introduction to Carbohydrates

Carbohydrates Introduction

• Carbohydrates include sugars, starches, and fibers found in fruits, grains, vegetables, and milk products.
• They are the main energy source for the body.
• Chemically, they consist primarily of carbon, hydrogen, and oxygen.
• They are polyhydroxy aldehydes or ketones or compounds yielding these upon hydrolysis.
• Formed in plants through photosynthesis from carbon dioxide and water in the presence of sunlight.
• Examples include cane sugar, glucose, and starch.

Carbohydrate Functions

• Used for energy storage and production (starch in plants, glycogen in animals).
• Glucose is crucial for nervous tissue and red blood cells.
• Ribose and deoxyribose are components of RNA and DNA structures.
• Serve as structural elements (e.g., cellulose in plant cell walls, chitin in arthropod exoskeletons).

Carbohydrate Classification

• Monosaccharides: Simplest form, polyhydroxy aldehydes or ketones.
  • Example of aldose: Glucose
  • Example of ketose: Fructose
• Disaccharides: Formed by two monosaccharides linked by a glycosidic bond.
  • Classified as reducing or non-reducing sugars.

Oligosaccharides & Polysaccharides

• Oligosaccharides: Composed of 3-10 monosaccharides linked by glycosidic bonds.
  • Occur as glycoconjugates (e.g., glycoproteins, glycolipids).
• Polysaccharides: Composed of more than 10 monosaccharides.
  • Serve as storage molecules (e.g., glycogen, starch) and structural support (e.g., cellulose).
  • Classified as homopolysaccharides or heteropolysaccharides.

Reducing and Non-reducing Sugars

• Classified based on their ability to act as reducing agents.

Industrial Applications of Carbohydrates

• Food and Beverage: Used as sweeteners, thickeners, and stabilizers.
• Pharmaceuticals: Act as excipients to improve drug stability and bioavailability.
• Cosmetics: Provide hydration in products like moisturizers and shampoos.
• Biotechnology: Used in biodegradable plastics and biofuels.
• Research: Serve as tools in immunology, virology, and cellular biology.

Cellulose-Based Water Filters

• Made from cellulose, a natural polymer from plant cell walls.
• Biodegradable, cost-effective, and renewable.
• Properties include high porosity, good mechanical strength, and chemical resistance.

Polyhydroxyalkanoates (PHAs)

• Biodegradable and produced by microorganisms.
• Made from renewable resources like sugar and cornstarch.
• Used in packaging, medical devices, textiles, and automotive parts.

Polylactic Acid (PLA)

• Made from natural resources like corn starch.
• Biodegradable under industrial composting conditions.
• Used in packaging, 3D printing, and various engineering applications.

Engineering Applications of PHA and PLA Bioplastics

• Used in automotive, electronic devices, aerospace, sporting goods, and medical equipment.
• Emphasis on biodegradability and suitability for sustainable solutions.

Limitations of Cellulose-Based Water Filters

• Low resistance to high temperatures.
• Limited filtration efficiency for heavy metals.
• Potential clogging and difficulty in sterilization.