Lec 8 Flashcards
What are Fibers/Mucilage?
Large, highly branched polymeric polysaccharides built from different sugars units and uronic acids.
What is the water absorption property of Fibers/Mucilage?
They are very hydrophilic and capable of trapping water to form a gel.
How do Fibers/Mucilage behave when mixed with water?
They swell to many times their original volume as they absorb water.
Classify dietary fibers based on water solubility.
- Insoluble fiber: celluloses, some hemicelluloses, and lignins.
- Soluble dietary fiber: β-glucans, pectins, gums, mucilages, and hemicelluloses.
What role do Fibers/Mucilage play as laxatives?
They act as bulk forming laxatives, bulking agents, and prebiotics.
What effect do Fibers/Mucilage have on stool consistency?
They bulk up and soften the stool, stimulating intestinal activity.
Which plants are traditionally used as laxatives?
- Linseed (flaxseed)
- Fenugreek (Trigonella foenum-graecum)
What are the prebiotic effects of Fibers/Mucilage?
They nourish the ‘good bacteria’ in the colon, especially after partial processing by the gastrointestinal tract.
What are common side effects of Fibers/Mucilage?
Flatulence and a feeling of fullness.
What precautions should be taken with Fibers/Mucilage?
May decrease absorption of concomitantly taken drugs and may cause intestinal blockage.
What is the composition of Linseed (linseed)?
- 3-6% mucilage
- 3-8% fibers
- 20-30% protein
- 30-45% fatty oil
What percentage of water-soluble fiber do psyllium seeds contain?
Approximately 85%.
What are the components of wheat bran?
- Cellulose
- Hemicellulose
- β-glucan
- Pectin
- Lignin
What are Pungent Principles?
A physiological classification rather than a phytochemical one, including compounds like capsaicin and piperine.
What are the effects of capsaicin and piperine?
They activate vanilloid receptors, playing a role in pain, inflammation, and thermoregulation.
What is tachyphylaxis?
A process where, at higher doses, capsaicin desensitizes nerve cells, providing pain relief.
What are the general warming effects of hot spices?
They stimulate circulatory activity.
What are the key components of Ginger?
- Essential oil (1-4%): sesquiterpenoids
- Pungent principles: gingerols (30%)
What is the primary pharmacodynamic effect of Ginger?
Antiemetic and antinausea activity.
What is the efficacy of Ginger in preventing postoperative nausea?
Confirmed by meta-analyses including five randomized trials.
What are the gastrointestinal effects of Ginger?
Increased GIT motility and inhibition of gastric ulcers.
What are the adverse effects of Ginger?
Minor gastrointestinal complaints, particularly stomach upset.
What should be cautioned when prescribing Ginger?
Daily doses over 4 g should be used cautiously in patients on blood thinners.
