Understanding the utilization of phytoconstituents is essential for B.Pharm students studying pharmacognosy, phytochemistry, and herbal drug development. This set of MCQs with answers focuses on extraction methods, isolation, characterization, standardization, bioavailability, pharmacological actions, therapeutic applications, dosage forms, safety, and quality control of plant-derived compounds. Emphasis is placed on real-world relevance such as method selection, formulation challenges, and regulatory considerations for phytomedicines. These questions reinforce core concepts like active constituent identification, structure–activity relationships, analytical techniques (TLC, HPLC, LC–MS, NMR), and clinical implications. Designed to build critical thinking and exam readiness, this resource integrates theory with practical aspects of phytoconstituent utilization. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which extraction method is best suited for heat-sensitive phytoconstituents while maximizing yield?
- Hot percolation using reflux
- Supercritical fluid extraction with CO2
- Soxhlet extraction with ethanol
- Hydrodistillation
Correct Answer: Supercritical fluid extraction with CO2
Q2. Which phytochemical class is most commonly associated with antioxidant activity due to phenolic hydroxyl groups?
- Alkaloids
- Flavonoids
- Saponins
- Terpenes
Correct Answer: Flavonoids
Q3. Which analytical technique provides the most direct information about the molecular mass of a phytoconstituent?
- UV–Vis spectroscopy
- NMR spectroscopy
- Mass spectrometry (MS)
- Infrared (IR) spectroscopy
Correct Answer: Mass spectrometry (MS)
Q4. For routine fingerprinting and preliminary identity testing of herbal extracts, which technique is most practical and widely used?
- LC–MS/MS quantitation
- Thin layer chromatography (TLC)
- GC–MS structural elucidation
- NMR metabolomics
Correct Answer: Thin layer chromatography (TLC)
Q5. Which solvent property is most important when selecting a solvent for extracting polar glycosides from plant material?
- Low boiling point
- High polarity
- Non-polarity
- High viscosity
Correct Answer: High polarity
Q6. Marker compounds used for standardization of herbal extracts are selected primarily because they are:
- Present in highest concentration regardless of activity
- Pharmacologically inactive but easy to measure
- Representative of therapeutic activity or chemically characteristic
- Always volatile and detectable by GC
Correct Answer: Representative of therapeutic activity or chemically characteristic
Q7. Which extraction technique uses rapid solvent flow through a packed bed and is efficient for large-scale processing?
- Maceration
- Percolation
- Ultrasonic-assisted extraction
- Soxhlet extraction
Correct Answer: Percolation
Q8. Which test is a classical qualitative chemical test for the presence of alkaloids in a crude plant extract?
- Froth test
- Dragendorff’s reagent test
- Ferric chloride test
- Liebermann–Burchard test
Correct Answer: Dragendorff’s reagent test
Q9. In HPLC method development for a polar flavonoid glycoside, which stationary phase is typically most suitable?
- C18 reversed-phase column
- Normal phase silica column
- Chiral stationary phase
- Size-exclusion column
Correct Answer: C18 reversed-phase column
Q10. Which parameter is NOT typically assessed during quality control of a standardized herbal extract?
- Assay of marker compound
- Microbial contamination
- Acute pharmacological potency in humans
- Heavy metals content
Correct Answer: Acute pharmacological potency in humans
Q11. Which form of phytoconstituent delivery improves oral bioavailability of poorly water-soluble triterpenes?
- Immediate-release tablets without surfactant
- Solid lipid nanoparticles or nanoemulsions
- Simple aqueous suspension
- Enteric-coated pellets of raw powder
Correct Answer: Solid lipid nanoparticles or nanoemulsions
Q12. Which phytoconstituent class commonly causes hemolytic activity and forms stable foam in aqueous solutions?
- Tannins
- Saponins
- Alkaloids
- Flavonoids
Correct Answer: Saponins
Q13. Which quality parameter addresses batch-to-batch consistency of an herbal extract?
- Organoleptic evaluation only
- Assay of marker compounds and fingerprinting
- Only microbial limits
- Packaging aesthetics
Correct Answer: Assay of marker compounds and fingerprinting
Q14. DNA barcoding in botanical authentication is primarily used to:
- Quantify active constituents
- Determine solvent residues
- Confirm plant species identity
- Measure particle size distribution
Correct Answer: Confirm plant species identity
Q15. Which of the following best describes the purpose of a standard extract?
- An extract with random composition
- An extract standardized to specified levels of one or more markers
- An unprocessed crude drug material
- A synthetic mixture of phytochemicals
Correct Answer: An extract standardized to specified levels of one or more markers
Q16. Which technique is most appropriate for volatile oil analysis and profiling of essential oils?
- HPLC with UV detection
- GC–MS (gas chromatography–mass spectrometry)
- Paper chromatography
- Capillary electrophoresis
Correct Answer: GC–MS (gas chromatography–mass spectrometry)
Q17. Which statement about structure–activity relationship (SAR) in phytoconstituents is true?
- SAR studies are irrelevant for natural products
- Minor structural changes can significantly alter biological activity
- Only the whole extract matters; individual structures do not
- SAR requires only melting point data
Correct Answer: Minor structural changes can significantly alter biological activity
Q18. Which regulatory document or guideline is commonly referenced for good manufacturing practices of herbal medicines?
- ICH Q2 only
- WHO guidelines on Good Manufacturing Practices for herbal medicines
- US EPA pesticide guidelines
- OECD chemical safety manuals
Correct Answer: WHO guidelines on Good Manufacturing Practices for herbal medicines
Q19. Which stability concern is most relevant for phenolic-rich herbal extracts?
- Oxidative degradation leading to loss of potency
- Polymerization into insoluble proteins
- Immediate conversion to alkaloids
- Becoming highly volatile
Correct Answer: Oxidative degradation leading to loss of potency
Q20. Which solvent is commonly used in Soxhlet extraction for non-polar terpenoids?
- Water
- Methanol
- Hexane
- Ethanol–water (50:50)
Correct Answer: Hexane
Q21. In quantifying a flavonoid by HPLC, which validation parameter ensures the method distinguishes the analyte from impurities?
- Precision
- Specificity
- Linearity
- Robustness
Correct Answer: Specificity
Q22. Which phytoconstituent group is commonly implicated in drug–herb interactions due to CYP450 induction or inhibition?
- Polysaccharides
- Starch polymers
- Alkaloids and flavonoids
- Inorganic salts
Correct Answer: Alkaloids and flavonoids
Q23. Which isolation technique separates compounds based on partitioning between immiscible solvents?
- Chromatography on silica gel
- Liquid–liquid extraction (partitioning)
- Freeze-drying
- Supercritical fluid chromatography
Correct Answer: Liquid–liquid extraction (partitioning)
Q24. Which assay is commonly used to estimate total phenolic content in an extract?
- BCA protein assay
- Folin–Ciocalteu reagent assay
- Kjeldahl nitrogen estimation
- Bradford assay
Correct Answer: Folin–Ciocalteu reagent assay
Q25. Which phytochemical test is indicative of the presence of tannins?
- Formation of blue color with ferric chloride
- Positive Liebermann–Burchard (green) test
- Precipitation with gelatin or lead acetate
- Formation of froth on shaking
Correct Answer: Precipitation with gelatin or lead acetate
Q26. Microencapsulation of a plant extract is primarily used to:
- Increase microbial load
- Decrease stability
- Mask taste, improve stability, and control release
- Prevent chromatographic analysis
Correct Answer: Mask taste, improve stability, and control release
Q27. Which parameter indicates the degree of lipophilicity of a phytoconstituent and influences absorption?
- pKa only
- Partition coefficient (log P)
- Melting point
- Refractive index
Correct Answer: Partition coefficient (log P)
Q28. Which analytical hyphenated technique is most powerful for both separation and structural identification of complex plant metabolites?
- Paper chromatography with UV lamp
- HPLC coupled to mass spectrometry (HPLC–MS)
- Gravimetric analysis
- Simple TLC with iodine vapor
Correct Answer: HPLC coupled to mass spectrometry (HPLC–MS)
Q29. Which adverse effect is commonly monitored during safety evaluation of alkaloid-containing herbal products?
- Hypersalivation only
- Hepatotoxicity and neurotoxicity
- Immediate polymerization
- Rapid crystallization in blood
Correct Answer: Hepatotoxicity and neurotoxicity
Q30. When developing a phytomedicine, what is the main benefit of using a standardized extract versus raw plant powder?
- Lower production cost always
- Guaranteed therapeutic consistency and reproducible dosing
- Eliminates need for clinical testing
- Makes the product fully synthetic
Correct Answer: Guaranteed therapeutic consistency and reproducible dosing
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.
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