Unorganized drugs such as oleoresins are concentrated plant extracts widely studied in pharmacognosy and applied in pharmaceutical formulations. Oleoresins combine a volatile oil and a non‑volatile resinous fraction, offering concentrated flavor, aroma, and bioactive compounds from spices (pepper, ginger, capsicum, paprika). B.Pharm students must master their definitions, extraction methods (solvent extraction, solvent recovery, vacuum concentration), analytical techniques (GC-MS, HPLC, TLC), stability issues (oxidation, storage), and standardization markers (piperine, capsaicin). This concise, keyword‑rich overview prepares you for applied quality control and formulation roles. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. What best describes “unorganized drugs” in pharmacognosy?
- Plant parts with defined histological structure like leaves and stems
- Mineral substances used in pharmacy
- Plant secretions or exudates lacking a definite cellular or organized form
- Synthetic mixtures produced in laboratories
Correct Answer: Plant secretions or exudates lacking a definite cellular or organized form
Q2. Which statement correctly defines an oleoresin?
- A pure volatile oil obtained by steam distillation
- A concentrated plant extract containing both volatile oil and non‑volatile resinous components
- A water‑soluble extract used for injection formulations
- A crystalline alkaloid isolated from plant tissues
Correct Answer: A concentrated plant extract containing both volatile oil and non‑volatile resinous components
Q3. What are the major constituents of typical spice oleoresins?
- Volatile oils, resinous (non‑volatile) fraction, and sometimes waxes or pigments
- Only triglycerides and fatty acids
- Pure chlorophyll and cellulose
- Only inorganic salts and minerals
Correct Answer: Volatile oils, resinous (non‑volatile) fraction, and sometimes waxes or pigments
Q4. Which industrial method is most commonly used to obtain oleoresins from spices?
- Direct steam distillation of whole spice
- Cold water maceration
- Solvent extraction followed by solvent removal/concentration
- Supercritical CO2 extraction for all spices without exception
Correct Answer: Solvent extraction followed by solvent removal/concentration
Q5. How does an oleoresin differ from an essential oil?
- Oleoresins are purely volatile; essential oils contain non‑volatile resins
- Oleoresins contain both volatile and non‑volatile resinous fractions, whereas essential oils are predominantly volatile
- Essential oils are solid at room temperature while oleoresins are gaseous
- There is no chemical difference between them
Correct Answer: Oleoresins contain both volatile and non‑volatile resinous fractions, whereas essential oils are predominantly volatile
Q6. Which solvent property is most suitable for extracting oleoresins from plant material?
- Highly polar and water miscible solvent only
- Non‑polar to moderately polar organic solvent that solubilizes volatile oils and resins
- Strongly acidic aqueous medium
- Pure supercritical nitrogen
Correct Answer: Non‑polar to moderately polar organic solvent that solubilizes volatile oils and resins
Q7. Which spice is commonly processed to produce an oleoresin used as both flavor and colorant?
- Clove essential oil
- Paprika oleoresin
- Tea leaf infusion
- Soybean oil
Correct Answer: Paprika oleoresin
Q8. Which analytical technique is most appropriate for detailed profiling of volatile components in an oleoresin?
- UV‑Vis spectrophotometry
- Gas chromatography‑mass spectrometry (GC‑MS)
- Atomic absorption spectroscopy
- Gravimetric moisture analysis
Correct Answer: Gas chromatography‑mass spectrometry (GC‑MS)
Q9. Which method is commonly used to estimate the non‑volatile resinous fraction in an oleoresin?
- Volatile distillation in a Clevenger apparatus
- Gravimetric determination after solvent evaporation and drying
- Flame photometry for metals
- pH titration with strong acid
Correct Answer: Gravimetric determination after solvent evaporation and drying
Q10. What is the primary cause of odor and potency loss in stored oleoresins?
- Polymerization to high molecular weight plastics
- Oxidation and volatilization of sensitive constituents
- Rapid crystallization into solid salts
- Complete conversion to water‑soluble sugars
Correct Answer: Oxidation and volatilization of sensitive constituents
Q11. Which antioxidant is frequently added to oleoresins to improve shelf stability?
- Sodium chloride
- Butylated hydroxytoluene (BHT)
- Hydrochloric acid
- Calcium carbonate
Correct Answer: Butylated hydroxytoluene (BHT)
Q12. For standardization of black pepper oleoresin, which marker compound is commonly quantified?
- Menthol
- Piperine
- Curcumin
- Capsaicin
Correct Answer: Piperine
Q13. Which term describes a concentrated resinous extract used mainly in perfumery and not necessarily containing a volatile oil?
- Oleoresin
- Resinoid
- Essential oil
- Fixed oil
Correct Answer: Resinoid
Q14. What industrial process is typically used to concentrate oleoresins after solvent extraction?
- Simple open‑pan boiling at atmospheric pressure
- Vacuum evaporation to remove solvent at reduced temperature
- Freeze‑drying at high temperatures
- Direct combustion of solvent to ash
Correct Answer: Vacuum evaporation to remove solvent at reduced temperature
Q15. Why are oleoresins often preferred over essential oils in food and pharmaceutical formulations?
- They are completely odorless and have no flavor
- They provide concentrated flavor, better stability, and non‑volatile color/pigment components
- They are aqueous solutions that dissolve in water easily
- They lack any bioactive compounds
Correct Answer: They provide concentrated flavor, better stability, and non‑volatile color/pigment components
Q16. Which technique is commonly used to convert liquid oleoresins into a free‑flowing powder for formulations?
- Spray drying with carriers like maltodextrin or adsorption onto carriers
- Direct freeze crystallization without carriers
- Electroplating onto metal sheets
- High‑temperature incineration
Correct Answer: Spray drying with carriers like maltodextrin or adsorption onto carriers
Q17. Which solvent is typically used as a non‑polar extractor in oleoresin production?
- Hexane
- Distilled water
- Concentrated nitric acid
- Saturated sodium chloride solution
Correct Answer: Hexane
Q18. For fingerprinting the resinous (non‑volatile) fraction of an oleoresin, which technique is commonly applied?
- Thin layer chromatography (TLC)
- Clevenger hydrodistillation
- Karl Fischer titration
- Conductivity measurement
Correct Answer: Thin layer chromatography (TLC)
Q19. Which property distinguishes oleoresins from fixed oils (triglyceride oils)?
- Oleoresins contain significant volatile oil components and resinous matter, while fixed oils are mainly triglycerides
- Fixed oils are aromatic volatile compounds only
- Oleoresins are purely water‑soluble substances
- Fixed oils contain essential oils and resins together
Correct Answer: Oleoresins contain significant volatile oil components and resinous matter, while fixed oils are mainly triglycerides
Q20. What is a major pharmaceutical use of oleoresins?
- As primary active injectable antibiotics
- As flavoring agents, excipients, and sometimes source of bioactive principles in formulations
- As bulk crystalline excipients for tablet compression
- As sterile aqueous eye drops
Correct Answer: As flavoring agents, excipients, and sometimes source of bioactive principles in formulations
Q21. The pungent principle of capsicum oleoresin responsible for heat is:
- Curcumin
- Piperine
- Capsaicin
- Gingerol
Correct Answer: Capsaicin
Q22. Which compound is a characteristic pungent constituent found in ginger oleoresin?
- Menthone
- Gingerol
- Linalool
- Thymol
Correct Answer: Gingerol
Q23. Which apparatus is traditionally used to determine the volatile oil content (hydrodistillation) that helps quantify the volatile fraction of a spice?
- Clevenger apparatus
- HPLC pump
- Karl Fischer titrator
- Atomic absorption spectrometer
Correct Answer: Clevenger apparatus
Q24. What is the recommended primary packaging for oleoresins to reduce deterioration?
- Clear PET bottles stored in direct sunlight
- Amber glass bottles or metal containers with inert atmosphere, protected from light and heat
- Open trays at ambient temperature
- Paper envelopes in humid storage
Correct Answer: Amber glass bottles or metal containers with inert atmosphere, protected from light and heat
Q25. During storage, which process most directly results in loss of aroma from an oleoresin?
- Polymer crosslinking forming rubber
- Evaporation of volatile constituents and oxidative degradation
- Precipitation of inorganic salts
- Conversion to stable ionic crystals
Correct Answer: Evaporation of volatile constituents and oxidative degradation
Q26. Which of the following statements about oleoresins is FALSE?
- They often contain pigments and non‑volatile flavor components
- They are typically water‑soluble
- They can be standardized against marker compounds like piperine or capsaicin
- They require antioxidant or proper packaging for stability
Correct Answer: They are typically water‑soluble
Q27. Which analytical technique is most suitable for simultaneous profiling of both volatile and non‑volatile constituents when used in combination?
- GC‑MS for volatiles and HPLC for non‑volatiles
- Microscopy alone
- Simple refractometry
- Paper chromatography only
Correct Answer: GC‑MS for volatiles and HPLC for non‑volatiles
Q28. Which oleoresin is predominantly used as a natural colorant and flavorant in foods?
- Black tea extract
- Paprika oleoresin
- Synthetic FD&C Red No. 40 only
- Pure glycerol
Correct Answer: Paprika oleoresin
Q29. Which extraction method is generally NOT suitable for obtaining an oleoresin (though it may yield an essential oil)?
- Solvent extraction using hexane or acetone
- Steam distillation targeting only volatile compounds
- Supercritical CO2 extraction tuned for both fractions
- Solvent extraction followed by concentration under reduced pressure
Correct Answer: Steam distillation targeting only volatile compounds
Q30. A simple laboratory test to detect adulteration of an oleoresin with added fixed vegetable oil is:
- Determination of saponification value or comparing fatty oil markers by GC
- Measuring pH with universal indicator paper
- Observing color change on exposure to UV light only
- Measuring electrical conductivity
Correct Answer: Determination of saponification value or comparing fatty oil markers by GC
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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