← Pharmacognosy and Phytopharmaceuticals Practicals

Macro, Powder and Microscopic Study of Senna

1. Aim

To document macroscopic, powder, and section-microscopic features of an authenticated Senna teaching specimen and compare them with a verified botanical reference. Actual species, part, and identity must be entered in the student record.

2. Requirements

Instructor-authenticated leaflets and possible pods, sealed display container or high-resolution specimen image, prepared powder slide, prepared transverse section or micrograph, microscope, hand lens, reference atlas, observation sheet, gloves, and approved disposal route. Actual species, plant part, slide preparation, stain, and magnification must be entered in the student record.

3. Theory

The syllabus names Senna, but a crude-drug name alone is insufficient to establish species, plant part, or authenticity. The candidate species Senna alexandrina is cited as a taxonomic reference, not assigned to the teaching sample. Begin with the labelled whole material, then compare its visible form with the powder and a prepared section. For this entry, useful observation targets include paired leaflet shape and margin in the whole material and epidermal fragments, stomata, and hairs in microscopic material. These are structures to look for, not claims that every supplied slide will display them. Powdering destroys much of the intact arrangement, so a fragment may need confirmation in a section. A species-specific monograph and control specimen are required before making a diagnostic claim. Senna alexandrina is a botanical candidate, but the supplied species and plant part require confirmation.

4. Procedure

1. Record the Senna specimen code, labelled botanical name, part, source, and reference used; unresolved label details must be entered in the student record.
2. Inspect the sealed leaflets and possible pods or its approved photograph and write direct observations of paired leaflet shape and margin.
3. Examine the instructor-prepared powder slide, beginning at low power, then record visible fragments without assigning an identity from one structure.
4. Inspect the prepared section or authenticated micrograph and locate tissue arrangements that might explain the powder fragments.
5. Compare all three views with the approved species- and part-specific reference, listing both matching and missing characters.
6. Write a conditional identification and note contamination, adulteration, or slide-quality concerns for instructor review.

5. Observation and calculation

Assumed observations for practice only: an assumed Senna display specimen shows assumed paired leaflets, and an assumed powder slide shows assumed an epidermal fragment. These invented observations show how to use the table. They do not identify a real specimen. The actual features, species, and conclusion must be entered in the student record. No mass, reagent volume, stain concentration, or therapeutic value is assumed.

6. Output or final result

Submit a labelled three-view record for Senna with evidence for and against the assigned identity. The actual identity and quality decision must be entered in the student record.

Teaching-lab safety: Use a sealed specimen and instructor-prepared slides. Do not taste, grind, inhale, or dispense the plant material.

This page is a supervised-activity guide; it does not report a completed case.

7. Sources

• PharmacoLearn Pharm.D Year 2 syllabus
• PCI Pharm.D Regulations and Syllabus
• Kew Plants of the World Online, relevant Senna taxon

Back to Pharmacognosy and Phytopharmaceuticals Practicals · All Pharm D Practicals · Pharm D

Theory notes: Pharmacognosy and Phytopharmaceuticals