Tragacanth – chemistry, sources, preparation, evaluation, preservation, storage, therapeutic uses and commercial utility MCQs With Answer

Tragacanth – chemistry, sources, preparation, evaluation, preservation, storage, therapeutic uses and commercial utility MCQs With Answer

Tragacanth is a natural gum from Astragalus species used widely as a pharmaceutical excipient. Its chemistry features complex polysaccharides—mainly water-soluble tragacanthin and swelling bassorin—giving high viscosity, pseudoplastic rheology and excellent mucilage formation. B.Pharm students should master sources, collection and purification, standard tests (viscosity, swelling index, ash, moisture, microbial limits), identification and detection of adulterants, and appropriate preservation and storage conditions. Clinical roles include demulcent, expectorant and suspending agent while commercial utility spans dosage forms, food and cosmetics. Practical knowledge of preparation, quality evaluation and stability ensures safe, effective use. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which two principal polysaccharide components characterize the chemistry of tragacanth gum?

• Cellulose and pectin
• Arabinogalactan and rhamnogalacturonan
• Tragacanthin (water-soluble) and bassorin (swelling)
• Maltose and sucrose

Correct Answer: Tragacanthin (water-soluble) and bassorin (swelling)

Q2. The primary botanical source of commercial tragacanth gum is which genus?

• Acacia
• Astragalus
• Gossypium
• Commiphora

Correct Answer: Astragalus

Q3. Which Astragalus species is commonly cited as a source of tragacanth?

• Astragalus gummifer
• Astragalus membranaceus
• Astragalus sinicus
• Astragalus canadensis

Correct Answer: Astragalus gummifer

Q4. Which property best explains tragacanth’s use as a suspending agent in liquid dosage forms?

• High sugar content
• Formation of viscous mucilage and pseudoplastic flow
• Volatility and low boiling point
• High crystallinity

Correct Answer: Formation of viscous mucilage and pseudoplastic flow

Q5. During primary processing, which step is essential to remove insoluble impurities from crude tragacanth?

• Acid hydrolysis with concentrated HCl
• Extraction with cold water and filtration
• Dry distillation
• Supercritical CO2 extraction

Correct Answer: Extraction with cold water and filtration

Q6. Which solvent is tragacanth largely insoluble in, distinguishing it from some other gums?

• Water
• Ethanol (alcohol)
• Dilute alkali
• Warm glycerin

Correct Answer: Ethanol (alcohol)

Q7. The swelling index of tragacanth primarily measures what attribute?

• Degree of crystallization
• Volume increase on hydration
• Protein contamination
• pH stability

Correct Answer: Volume increase on hydration

Q8. Which analytical test is commonly used to evaluate the viscosity of tragacanth mucilage?

• UV-Vis spectroscopy
• Brookfield viscometry
• Flame photometry
• Gel permeation chromatography

Correct Answer: Brookfield viscometry

Q9. A typical quality control parameter to detect inorganic contaminants in tragacanth is:

• Acid-insoluble ash
• Specific gravity
• Optical rotation
• Melting point

Correct Answer: Acid-insoluble ash

Q10. Which microbial limit test is particularly relevant for tragacanth used in oral formulations?

• Total viable aerobic count
• Radioactivity assay
• Thermogravimetric analysis
• pKa determination

Correct Answer: Total viable aerobic count

Q11. Which of the following is a common adulterant of tragacanth gum?

• Starch
• Glycerin
• Calcium carbonate
• Lanolin

Correct Answer: Starch

Q12. A simple identification test for tragacanth involves mixing with water to observe:

• Immediate dissolution producing a clear solution
• Formation of a viscous mucilage and swelling
• Rapid evolution of gas
• Formation of crystals

Correct Answer: Formation of a viscous mucilage and swelling

Q13. Proper storage conditions for tragacanth to maintain quality include:

• High humidity and exposure to sunlight
• Cool, dry place in airtight containers
• Open trays at room temperature
• Submerged in water

Correct Answer: Cool, dry place in airtight containers

Q14. To preserve tragacanth from microbial growth during storage, which measure is commonly recommended?

• Adding strong oxidizers
• Maintaining low moisture and using preservatives where appropriate
• Exposing to UV light continuously
• Mixing with sucrose

Correct Answer: Maintaining low moisture and using preservatives where appropriate

Q15. In pharmaceutical formulations, tragacanth is least likely used as which excipient?

• Suspending agent
• Tablet disintegrant
• Emulsifying agent
• Gelling and stabilizing agent

Correct Answer: Tablet disintegrant

Q16. Which therapeutic use of tragacanth is historically recognized?

• Antibiotic activity
• Demulcent and expectorant
• Antiarrhythmic agent
• Hypoglycemic agent

Correct Answer: Demulcent and expectorant

Q17. The commercial utility of tragacanth in the food and cosmetic industries is mainly due to its:

• Sweetening power
• Thickening, stabilizing and emulsifying properties
• Strong fragrance
• High protein content

Correct Answer: Thickening, stabilizing and emulsifying properties

Q18. Which standard parameter helps detect vegetable matter and foreign organic matter in tragacanth?

• Loss on drying
• Total ash
• Mesh size only
• Specific rotation

Correct Answer: Total ash

Q19. Which pH range is generally acceptable for tragacanth mucilage in aqueous formulations to avoid degradation?

• Extremely acidic (pH 1–2)
• Strongly alkaline (pH 12–13)
• Near neutral to mildly acidic (pH 4–8)
• Any pH without consequence

Correct Answer: Near neutral to mildly acidic (pH 4–8)

Q20. During purification of crude tragacanth, precipitation of impurities is often aided by addition of:

• Excess hot ethanol
• Acetone or alcohol to precipitate polysaccharide fractions
• Strong base to hydrolyze gums
• Concentrated sulfuric acid

Correct Answer: Acetone or alcohol to precipitate polysaccharide fractions

Q21. Which rheological behavior is typically exhibited by tragacanth mucilage useful in topical formulations?

• Newtonian flow with constant viscosity
• Pseudoplastic or shear-thinning behavior
• Dilatant (shear-thickening) behavior
• Plastic flow with yield point only

Correct Answer: Pseudoplastic or shear-thinning behavior

Q22. A pharmaceutical student assessing tragacanth should include which test to evaluate water-binding and hydration capacity?

• Swelling index
• Melting point
• Optical rotation
• Conductivity at 100°C

Correct Answer: Swelling index

Q23. Which chromatography technique is most appropriate to profile monosaccharide composition after hydrolysis of tragacanth?

• Gas chromatography (GC) after derivatization
• Thin layer chromatography with CCl4 solvent
• Size-exclusion with non-aqueous mobile phase only
• Paper chromatography with methanol only

Correct Answer: Gas chromatography (GC) after derivatization

Q24. To ensure batch-to-batch consistency of tragacanth used as an excipient, manufacturers should routinely monitor:

• Viscosity, moisture content, ash, and microbial limits
• Color under ultraviolet only
• Protein content only
• Radioactivity

Correct Answer: Viscosity, moisture content, ash, and microbial limits

Q25. When tragacanth is used in emulsion formulations, its primary role is to:

• Act as a preservative
• Stabilize droplets and increase viscosity to prevent coalescence
• Act as a surfactant that reduces pH
• Prevent ionization of active drug

Correct Answer: Stabilize droplets and increase viscosity to prevent coalescence

Q26. Which statement about tragacanth’s solubility and gel formation is correct?

• Bassorin dissolves completely in cold water
• Tragacanthin dissolves to form mucilage while bassorin swells to form gel
• Both components are insoluble in water
• Both components are volatile

Correct Answer: Tragacanthin dissolves to form mucilage while bassorin swells to form gel

Q27. Adulteration of tragacanth with other gums can be most effectively detected by:

• Visual color only
• Specific viscosity profile and microscopy
• Smell alone
• Loss on drying only

Correct Answer: Specific viscosity profile and microscopy

Q28. For long-term commercial storage, packaging for tragacanth should be:

• Permeable paper sacks without liners
• Airtight, moisture-proof containers with desiccant if needed
• Stored in open bins
• Mixed with water to maintain hydration

Correct Answer: Airtight, moisture-proof containers with desiccant if needed

Q29. Which safety consideration is important when using tragacanth in oral pharmaceutical products?

• It is highly toxic at low doses
• Potential microbial contamination and moisture uptake must be controlled
• It causes immediate systemic absorption of co-administered drugs
• It reacts violently with glass

Correct Answer: Potential microbial contamination and moisture uptake must be controlled

Q30. In formulation development, why might a formulator choose tragacanth over synthetic polymers?

• It always gives lower viscosity than synthetics
• Natural origin, biocompatibility, and multifunctional excipient properties
• It is cheaper than all synthetics in every case
• It makes formulations electrically conductive

Correct Answer: Natural origin, biocompatibility, and multifunctional excipient properties

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com