RH Herbal Preparations & Dosage Forms 2 — Questions and Answers
Question 1: In herbal extraction terminology, the 'marc' refers to:
- The finished liquid extract ready for dispensing
- The spent plant material remaining after pressing the extract (Correct answer)
- The ratio of herb weight to menstruum volume
- A type of traditional French distillate
Correct answer: The spent plant material remaining after pressing the extract
The marc is the exhausted plant material (spent herb) left after the liquid menstruum has been pressed or drained away from the extraction vessel.
Question 2: Percolation is preferred over simple maceration primarily because it:
- Requires significantly less alcohol to complete the extraction
- Continuously exposes plant material to fresh menstruum, maintaining an extraction gradient (Correct answer)
- Produces a more dilute and gentler extract suitable for sensitive patients
- Requires less equipment and is faster to complete
Correct answer: Continuously exposes plant material to fresh menstruum, maintaining an extraction gradient
In percolation, fresh menstruum continuously replaces saturated solvent, maintaining a concentration gradient that drives more complete extraction of plant constituents.
Question 3: Acetum herbal preparations use which primary menstruum?
- Apple cider vinegar or food-grade acetic acid solution (Correct answer)
- Ethanol at 60–70% concentration
- Vegetable glycerin diluted with distilled water
- Distilled water only
Correct answer: Apple cider vinegar or food-grade acetic acid solution
Acetum preparations use apple cider vinegar or food-grade acetic acid as the solvent, which is particularly effective at extracting minerals and certain alkaloids from plant material.
Question 4: Standardized herbal extracts are 'standardized' to ensure:
- A fixed volume of finished product per batch
- A consistent percentage of one or more identified marker compounds per dose (Correct answer)
- A uniform alcohol percentage regardless of the herb extracted
- The total dried herb weight is equal across batches
Correct answer: A consistent percentage of one or more identified marker compounds per dose
Standardization guarantees that each dose contains a specified percentage of key active or marker compounds (e.g., 0.3% hypericin in St. John's Wort extract) for consistent potency.
Question 5: For a client who needs rapid absorption and precise dose adjustment, which dosage form is most appropriate?
- Capsules filled with dried powdered herb
- Standardized film-coated tablets
- Liquid tincture or fluid extract (Correct answer)
- Bulk loose-leaf herbal tea
Correct answer: Liquid tincture or fluid extract
Liquid tinctures and fluid extracts are absorbed more rapidly than solid forms because they bypass the dissolution step, and doses can be easily titrated with a dropper.
Question 6: A Soxhlet extraction apparatus is used in herbal medicine primarily to:
- Prepare fresh-plant tinctures at low temperatures to preserve labile compounds
- Perform exhaustive extraction using a continuously recycling solvent system (Correct answer)
- Concentrate aqueous decoctions by controlled evaporation
- Quantify total alkaloid content in dried plant samples
Correct answer: Perform exhaustive extraction using a continuously recycling solvent system
The Soxhlet apparatus recycles solvent through plant material repeatedly, achieving exhaustive extraction commonly used in standardized extract production and research.
Question 7: The shelf life of a properly prepared hydroethanolic tincture stored in amber glass away from heat is generally:
- 6–12 months
- 1–2 years
- 3–5 years or longer (Correct answer)
- 30 days without refrigeration
Correct answer: 3–5 years or longer
Tinctures with adequate alcohol content (40% or above) stored properly in amber glass away from light and heat are stable for 3–5 years or longer due to alcohol's preservative action.
RH Herbal Preparations & Dosage Forms 2
In herbal extraction terminology, the 'marc' refers to: