Processing of herbal raw materials involves critical operations—collection, authentication, drying, milling, extraction, purification and storage—ensuring phytochemical integrity and therapeutic efficacy. For B.Pharm students, mastering concepts like Good Agricultural and Collection Practices (GACP), moisture control, particle size, extraction techniques (maceration, percolation, Soxhlet, supercritical fluid), standardization, chromatographic fingerprinting, and quality control tests (ash values, loss on drying, microbial limits, pesticide residues) is essential for safe herbal product development. Practical understanding of stabilization, packaging, and regulatory compliance links pharmacognosy to pharmaceutical formulation and stability. This topic emphasizes analytical methods, process parameters and prevention of adulteration for consistent drug quality.
Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which drying method best preserves heat-sensitive volatile oils in aromatic herbs?
- Oven drying at 80°C
- Sun drying on open trays
- Shade drying at ambient temperature
- Microwave drying at high power
Correct Answer: Shade drying at ambient temperature
Q2. What is the primary purpose of size reduction (milling) of herbal raw materials?
- To increase hygroscopicity
- To increase surface area for efficient extraction
- To remove inorganic contaminants
- To sterilize the material
Correct Answer: To increase surface area for efficient extraction
Q3. Which parameter is most critical to control during drying to prevent microbial growth and enzymatic degradation?
- Ambient light intensity
- Final moisture content (loss on drying)
- Particle size distribution
- Bulk density
Correct Answer: Final moisture content (loss on drying)
Q4. Which extraction technique is best for exhaustive extraction of non-volatile constituents from a solid herbal matrix?
- Cold percolation for 5 minutes
- Maceration with intermittent agitation
- Soxhlet extraction with appropriate solvent
- Steam distillation
Correct Answer: Soxhlet extraction with appropriate solvent
Q5. For extracting thermolabile glycosides, which solvent and method combination is most suitable?
- Hot water decoction at boiling for 2 hours
- Ethanolic maceration at room temperature
- Supercritical CO2 extraction at high temperature
- Direct steam distillation
Correct Answer: Ethanolic maceration at room temperature
Q6. Which test detects inorganic contamination such as sand, soil and mineral residues in herbal material?
- Loss on drying
- Total ash and acid-insoluble ash
- Microbial limit test
Correct Answer: Total ash and acid-insoluble ash
Q7. During herbal processing, what is the major risk of overdrying at elevated temperatures?
- Increase in microbial load
- Enhanced extraction yield of polar compounds
- Degradation of heat-sensitive phytoconstituents
- Reduction in particle size
Correct Answer: Degradation of heat-sensitive phytoconstituents
Q8. Which analytical technique is most appropriate for fingerprinting and standardization of complex herbal extracts?
- Gravimetric ash determination
- High-Performance Liquid Chromatography (HPLC) or HPTLC
- Loss on drying measurement
- Bulk density test
Correct Answer: High-Performance Liquid Chromatography (HPLC) or HPTLC
Q9. Which practice helps prevent adulteration and ensures traceability of herbal raw materials?
- Ignoring botanical authentication
- Implementing Good Agricultural and Collection Practices (GACP)
- Storing all herbs in a single bulk container
- Using only visual inspection at receipt
Correct Answer: Implementing Good Agricultural and Collection Practices (GACP)
Q10. What is the main advantage of supercritical CO2 extraction for herbal processing?
- High extraction of polar sugars without modifiers
- Selective extraction of non-polar compounds without thermal degradation
- Lowest capital equipment cost
- Ability to extract heavy metals
Correct Answer: Selective extraction of non-polar compounds without thermal degradation
Q11. Which parameter measured during quality control indicates presence of residual solvents?
- Limit of foreign matter
- Gas Chromatography (GC) for residual solvents
- Acid-insoluble ash
- Moisture content by Karl Fischer only
Correct Answer: Gas Chromatography (GC) for residual solvents
Q12. For volatile oil-rich herbs, which packing material property is most important to preserve quality?
- High oxygen permeability
- Light transparency
- Low moisture and oxygen permeability with opaque barrier
- High elasticity
Correct Answer: Low moisture and oxygen permeability with opaque barrier
Q13. Which step in processing is essential to remove extraneous organic matter like stems and leaves from collected roots?
- Maceration
- Cleaning and sorting
- Freeze-drying
- Supercritical extraction
Correct Answer: Cleaning and sorting
Q14. Which quality parameter assesses powder flow behavior important for dosage form manufacturing?
- Ash value
- Bulk density and tapped density (Hausner ratio)
- Moisture sorption isotherm only
- Chromatographic fingerprint
Correct Answer: Bulk density and tapped density (Hausner ratio)
Q15. Which method is most suitable for rapid screening of major phytochemical classes in raw herbal extracts?
- Phytochemical spot tests and preliminary chemical tests
- Full toxicology study
- Shelf-life stability test
- GC-MS heavy metal analysis
Correct Answer: Phytochemical spot tests and preliminary chemical tests
Q16. What is the purpose of blanching some herbal materials prior to drying?
- To increase enzyme activity
- To inactivate enzymes and reduce microbial load
- To add moisture for better extraction
- To decrease extractable constituents
Correct Answer: To inactivate enzymes and reduce microbial load
Q17. Which process is most appropriate for obtaining concentrated extracts from a hydroalcoholic herbal macerate?
- Direct freeze-thaw cycles
- Rotary evaporation under reduced pressure
- Open air evaporation at room temperature
- Sun drying of whole macerate
Correct Answer: Rotary evaporation under reduced pressure
Q18. Which analytical test helps detect pesticide residues in herbal raw materials?
- HPTLC fingerprinting only
- Liquid chromatography–mass spectrometry (LC-MS) or GC-MS targeted analysis
- Total ash determination
- Bulk density measurement
Correct Answer: Liquid chromatography–mass spectrometry (LC-MS) or GC-MS targeted analysis
Q19. How does particle size affect extraction kinetics of herbal constituents?
- Smaller particle size decreases surface area and slows extraction
- Larger particles always give higher extraction yield
- Smaller particle size increases surface area and speeds up mass transfer
- Particle size has no impact on extraction
Correct Answer: Smaller particle size increases surface area and speeds up mass transfer
Q20. Which method best preserves both volatile and non-volatile constituents for subsequent analysis?
- High-temperature oven drying
- Freeze-drying (lyophilization)
- Extended sun drying with direct sunlight
- Prolonged boiling in water
Correct Answer: Freeze-drying (lyophilization)
Q21. In herbal processing, what is the role of standard marker compounds?
- To serve as contaminants
- To quantify and ensure batch-to-batch consistency
- To increase ash values
- To reduce extraction efficiency
Correct Answer: To quantify and ensure batch-to-batch consistency
Q22. Which step helps reduce microbial contamination in herbal raw materials during storage?
- Storing at high relative humidity
- Maintaining low moisture content and controlled temperature
- Mist-spraying with water weekly
- Keeping in transparent sacks under sunlight
Correct Answer: Maintaining low moisture content and controlled temperature
Q23. What is the advantage of using polar protic solvents like ethanol-water mixtures for herbal extraction?
- They selectively extract only non-polar lipids
- They extract a wide range of polar and semi-polar phytoconstituents
- They remove inorganic ash selectively
- They are the best for volatile oil recovery
Correct Answer: They extract a wide range of polar and semi-polar phytoconstituents
Q24. Which practice is essential for botanical authentication of raw herbal drugs?
- Relying solely on supplier reputation
- Macroscopic and microscopic examination along with chemical tests
- Only measuring moisture content
- Performing only microbial limit tests
Correct Answer: Macroscopic and microscopic examination along with chemical tests
Q25. Which parameter is most relevant when choosing solvent for Soxhlet extraction?
- Boiling point relative to target constituents’ stability
- Color of the solvent
- Supplier brand
- Container shape
Correct Answer: Boiling point relative to target constituents’ stability
Q26. What is the significance of microbial limit tests in herbal raw materials?
- To increase ash values
- To ensure herbal materials comply with safety limits for pathogens and total counts
- To measure volatile oil content
- To determine particle size
Correct Answer: To ensure herbal materials comply with safety limits for pathogens and total counts
Q27. Which processing control minimizes enzymatic browning in certain herbal tissues?
- Increasing ambient humidity
- Blanching or treating with mild heat immediately after harvest
- Delaying drying by several days
- Storing at high temperature
Correct Answer: Blanching or treating with mild heat immediately after harvest
Q28. During large-scale extraction, which unit operation helps concentrate extracts without significant thermal degradation?
- Open vat evaporation at ambient pressure
- Vacuum evaporation/rotary evaporator under reduced pressure
- Direct prolonged boiling
- Sun evaporation
Correct Answer: Vacuum evaporation/rotary evaporator under reduced pressure
Q29. Which indicator suggests poor harvesting practices and potential contamination at collection?
- Low foreign matter and clean appearance
- High levels of extraneous matter and inconsistent botanical features
- Consistent phytochemical fingerprint across batches
- Low moisture and good particle uniformity
Correct Answer: High levels of extraneous matter and inconsistent botanical features
Q30. What is the primary reason for conducting accelerated stability studies on processed herbal extracts?
- To determine initial moisture only
- To predict shelf-life and identify degradation pathways under stress conditions
- To enhance extraction yield artificially
- To reduce ash values
Correct Answer: To predict shelf-life and identify degradation pathways under stress conditions
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