Other terpenoids – Artemisia MCQs With Answer

Introduction

Artemisia species produce a rich array of other terpenoids besides artemisinin, including monoterpenes (camphor, 1,8‑cineole), sesquiterpene lactones (santonin, absinthin) and diverse diterpenes. For B.Pharm students, understanding chemical classes, biosynthetic enzymes (ADS, CYP71AV1, DBR2, ALDH1), extraction methods (steam distillation, solvent and supercritical CO2), analytical techniques (GC‑MS, HPLC) and pharmacological profiles (antimalarial action, toxicity, formulation) is essential. Emphasis on structure–activity relationships—especially the endoperoxide in artemisinin and lactone motifs in other sesquiterpenoids—connects chemistry to clinical relevance, resistance issues and quality control. Now let’s test your knowledge with 30 MCQs on this topic.

Q1. Which structural feature is characteristic of many sesquiterpene lactones found in Artemisia?

• An endoperoxide 1,2,4‑trioxane ring
• A γ‑lactone (alpha‑methylene‑γ‑butyrolactone) moiety
• A cyclopropane ring
• A tertiary amine group

Correct Answer: A γ‑lactone (alpha‑methylene‑γ‑butyrolactone) moiety

Q2. Which enzyme catalyzes the first committed step in artemisinin biosynthesis from farnesyl diphosphate?

• CYP71AV1 (cytochrome P450)
• DBR2 (double bond reductase 2)
• ADS (amorpha‑4,11‑diene synthase)
• ALDH1 (aldehyde dehydrogenase 1)

Correct Answer: ADS (amorpha‑4,11‑diene synthase)

Q3. Which Artemisia terpenoid historically used as an anthelmintic is a sesquiterpene lactone?

• Camphor
• Santonin
• 1,8‑Cineole
• Artemether

Correct Answer: Santonin

Q4. Which analytical technique is most suitable for profiling volatile monoterpenes in Artemisia essential oil?

• HPLC with UV detection
• GC‑MS
• Gel electrophoresis
• IR spectroscopy only

Correct Answer: GC‑MS

Q5. The antimalarial activity of artemisinin primarily depends on which structural feature?

• Alpha‑methylene‑γ‑lactone
• Endoperoxide (1,2,4‑trioxane) bridge
• Aromatic nitro group
• Quinoline nucleus

Correct Answer: Endoperoxide (1,2,4‑trioxane) bridge

Q6. Which solvent is commonly used for extracting nonvolatile terpenoids from Artemisia leaves in laboratory-scale isolation?

• Hexane or petroleum ether
• Distilled water
• Acetonitrile for proteins
• Buffered saline

Correct Answer: Hexane or petroleum ether

Q7. Which enzyme oxidizes amorpha‑4,11‑diene to artemisinic alcohol and aldehyde in artemisinin biosynthesis?

• DBR2
• CYP71AV1 (a cytochrome P450 monooxygenase)
• ADS
• ALDH1

Correct Answer: CYP71AV1 (a cytochrome P450 monooxygenase)

Q8. Which Artemisia compound is associated with neurotoxicity and is a monoterpene ketone found in some species?

• Thujone
• Artesunate
• Santonin
• Camphene

Correct Answer: Thujone

Q9. Which artemisinin derivative is the active metabolite formed after oral activation and responsible for rapid parasite clearance?

• Artemether
• Dihydroartemisinin (DHA)
• Chloroquine
• Quinine

Correct Answer: Dihydroartemisinin (DHA)

Q10. Supercritical CO2 extraction is preferred for essential oil components because it provides:

• High thermal degradation of sensitive terpenoids
• Selective, solvent‑free extraction with low thermal damage
• Only polar compound extraction
• Complete denaturation of enzymes

Correct Answer: Selective, solvent‑free extraction with low thermal damage

Q11. Which gene mutation in Plasmodium falciparum is strongly associated with artemisinin resistance?

• pfcrt K76T
• pfmdr1 N86Y
• kelch13 (pfkelch13) propeller domain mutations
• dhfr S108N

Correct Answer: kelch13 (pfkelch13) propeller domain mutations

Q12. Which functional group commonly found in monoterpenes contributes to characteristic minty or camphoraceous odor in Artemisia oils?

• Ester linkage
• Ketone (e.g., camphor)
• Carboxylic acid
• Sulfhydryl group

Correct Answer: Ketone (e.g., camphor)

Q13. DBR2 in the artemisinin pathway catalyzes which conversion?

• Reduction of artemisinic aldehyde to dihydroartemisinic aldehyde
• Oxidation of amorpha‑4,11‑diene to alcohol
• Synthesis of farnesyl diphosphate
• Polymerization of terpenes

Correct Answer: Reduction of artemisinic aldehyde to dihydroartemisinic aldehyde

Q14. Which quality control marker is commonly quantified by HPLC in Artemisia annua extracts aimed at antimalarial use?

• Thujone
• Artemisinin content
• Chlorophyll concentration
• Glucose content

Correct Answer: Artemisinin content

Q15. Absinthin, a bitter principle from Artemisia absinthium, is classified as which type of terpenoid?

• Monoterpene alcohol
• Sesquiterpene lactone
• Triterpene saponin
• Polyphenol

Correct Answer: Sesquiterpene lactone

Q16. Photooxidation of which intermediate is proposed as a nonenzymatic step in forming the endoperoxide of artemisinin?

• Farnesyl diphosphate
• Dihydroartemisinic acid
• Camphor
• Santonin

Correct Answer: Dihydroartemisinic acid

Q17. Which formulation strategy improves oral bioavailability of poorly water‑soluble terpenoids like artemether?

• Use of plain aqueous suspension only
• Lipid‑based formulations or self‑emulsifying drug delivery systems
• Crystallization into larger particles
• Administering with antacids exclusively

Correct Answer: Lipid‑based formulations or self‑emulsifying drug delivery systems

Q18. Which phytochemical test or spectral signal would help confirm an α‑methylene‑γ‑lactone in a sesquiterpene?

• Strong IR absorption around 1740 cm‑1 and 1H NMR signal for exocyclic methylene
• Positive Biuret test
• Characteristic sugar‑derived signals only
• High melting point above 400 °C

Correct Answer: Strong IR absorption around 1740 cm‑1 and 1H NMR signal for exocyclic methylene

Q19. Which Artemisia species is the primary commercial source of artemisinin?

• Artemisia absinthium
• Artemisia vulgaris
• Artemisia annua
• Artemisia dracunculus

Correct Answer: Artemisia annua

Q20. Which statement about essential oil composition in Artemisia is correct?

• Composition is uniform across species and unaffected by geography
• Monoterpenes and sesquiterpenes vary with species, chemotype, harvest time and geography
• Only sesquiterpenes are present; monoterpenes are absent
• Essential oils contain only polar alkaloids

Correct Answer: Monoterpenes and sesquiterpenes vary with species, chemotype, harvest time and geography

Q21. Which pharmacokinetic property is a clinical concern for artemisinin derivatives when used as monotherapy?

• Extremely long half‑life leading to accumulation
• Rapid clearance and short half‑life risking recrudescence if used alone
• No oral absorption at all
• Exclusive renal excretion without metabolism

Correct Answer: Rapid clearance and short half‑life risking recrudescence if used alone

Q22. Which compound in Artemisia essential oil contributes to expectorant and bronchodilator effects?

• 1,8‑Cineole (eucalyptol)
• Santonin
• Artemisinin
• DBR2 enzyme

Correct Answer: 1,8‑Cineole (eucalyptol)

Q23. For chromatographic fingerprinting of terpenoid profiles, which detector complements GC‑MS for nonvolatile fraction analysis?

• HPLC‑PDA or HPLC‑MS for less volatile sesquiterpenes and lactones
• Paper chromatography with iodine only
• Capillary electrophoresis for volatile oils only
• Flame photometry specific for terpenoids

Correct Answer: HPLC‑PDA or HPLC‑MS for less volatile sesquiterpenes and lactones

Q24. Which safety consideration is important when handling concentrated Artemisia essential oils in the lab?

• They are inert and require no PPE
• They can be irritant, phototoxic or neurotoxic; use gloves and avoid skin/eye contact
• They are strong acids and require neutralization
• They are highly radioactive

Correct Answer: They can be irritant, phototoxic or neurotoxic; use gloves and avoid skin/eye contact

Q25. Which biotechnological approach has been used to increase production of artemisinin precursors?

• CRISPR editing of human cells only
• Heterologous expression of pathway enzymes in yeast or tobacco
• Using only traditional soil fertilization
• Diluting plant extracts to increase yield

Correct Answer: Heterologous expression of pathway enzymes in yeast or tobacco

Q26. Which statement correctly describes santonin’s pharmacology relevant to B.Pharm studies?

• Santonin is an effective modern antimalarial with a 1,2,4‑trioxane
• Santonin was historically used as an anthelmintic; toxicity limits its modern use
• Santonin is a peptide antibiotic
• Santonin is a polysaccharide used as an excipient

Correct Answer: Santonin was historically used as an anthelmintic; toxicity limits its modern use

Q27. Which in vitro assay is commonly used to assess antiplasmodial activity of Artemisia terpenoids?

• MTT assay on bacteria
• Inhibition of P. falciparum culture growth measured by SYBR Green or microscopy
• Blood glucose measurement
• Protein gel electrophoresis

Correct Answer: Inhibition of P. falciparum culture growth measured by SYBR Green or microscopy

Q28. Which storage condition best preserves volatile terpenoid composition in dried Artemisia leaves?

• Exposed to sunlight at room temperature
• Stored in dark, airtight containers at cool temperatures
• High humidity unsealed storage
• Frozen with repeated freeze‑thaw cycles

Correct Answer: Stored in dark, airtight containers at cool temperatures

Q29. Which combination therapy principle is recommended to prevent resistance when using artemisinin derivatives?

• Use artemisinin monotherapy for longer duration
• Combine artemisinin derivatives with a partner drug in ACT (Artemisinin‑based Combination Therapy)
• Alternate artemisinin with antibiotics daily
• Use artemisinin with antifungals only

Correct Answer: Combine artemisinin derivatives with a partner drug in ACT (Artemisinin‑based Combination Therapy)

Q30. Which property of many sesquiterpene lactones explains their bioactivity and potential for allergic contact dermatitis?

• High polarity preventing cell entry
• Electrophilic α‑methylene‑γ‑lactone that can alkylate nucleophiles in proteins
• Stable inert aromaticity
• Large sugar moieties making them nonreactive

Correct Answer: Electrophilic α‑methylene‑γ‑lactone that can alkylate nucleophiles in proteins

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