Plantago Seed
(plan tay' goe).
DEFINITION
Plantago Seed is the cleaned, dried, ripe seed of Plantago psyllium auct. or of Plantago indica L. (Plantago arenaria Waldst. & Kit.), known in commerce as Spanish or French psyllium; or of Plantago ovata Forssk., known in commerce as blond psyllium, or Indian plantago seed (Fam. Plantaginaceae).
SPECIFIC TESTS
•  Botanic Characteristics
Macroscopic 
Unground Plantago psyllium auct. seed:  Ovate to ovate-elongate, concavo-convex; mostly from 1.3 to 2.7 mm in length, rarely up to 3 mm, and from 600 µm to 1.1 mm in width. It is light brown to moderate brown, darker along the margin, and very glossy; the convex dorsal surface exhibiting a lighter colored longitudinal area extending nearly the length of the seed and representing the embryo lying beneath the seed coat, and showing a sometimes indistinct transverse groove nearer the broader end. The concave ventral surface has a deep cavity, in the center of the base of which is an oval, yellowish white hilum.
Unground Plantago indica seed:  Ovate-oblong to elliptical, concavo-convex; from 1.6 to 3 mm in length and from 1 to 1.5 mm in width. Externally it is dark reddish brown to moderate yellowish brown, occasionally somewhat glossy, often dull, rough, and reticulate; the convex dorsal surface having a longitudinal lighter colored area extending lengthwise along the center and beneath the seed coat, and a median transverse groove, dent, or fissure. The ventral surface has a deep concavity, the edges somewhat flattened and frequently forming a sharp indented angle with the base of the cavity, the latter showing a light colored oval hilum.
Unground Plantago ovata seed:  Broadly elliptical to ovate, boat-shaped, from 2 to 3.5 mm in length and from 1 to 1.5 mm in width. It is pale brown to moderate brown with a dull surface, the convex surface having a small, elongated, glossy brown spot. The concave surface has a deep cavity, in the center of the base of which occurs a hilum covered with a thin membrane.
Odor and taste:  All varieties of Plantago Seed are nearly odorless.
Microscopic:  Plantago Seed is reniform in median transverse sections. Its seed coat has a colorless epidermis of mucilaginous cells whose radial and outer walls break down to form layers of mucilage when brought into contact with water, and a reddish brown to yellow pigment layer in the seeds of Plantago indica and Plantago psyllium, a broad endosperm with thick-walled outer palisade cells, and irregular inner endosperm cells; and a straight embryo extending lengthwise through the center. The endosperm and embryo cells contain fixed oil and aleurone grains, the latter being rounded, oval, pyriform, or irregularly shaped, from 2 to 8 µm in diameter.
•  Water Absorption
Sample:  1 g of Plantago Seed
Analysis:  Place the Sample in a 25-mL graduated cylinder, add water to the 20-mL mark, and shake the cylinder at intervals during 24 h. Allow the seeds to settle for 12 h, and note the total volume occupied by the swollen seeds.
Acceptance criteria:  Seeds occupy the following volumes: Plantago psyllium, NLT 14 mL; Plantago ovata, NLT 10 mL; Plantago indica, NLT 8 mL.
ADDITIONAL REQUIREMENTS
•  Packaging and Storage: Preserve in well-closed containers, secure against insect attack.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Maged H. Sharaf, Ph.D.
Principal Scientific Liaison
1-301-816-8318
(DS2010) Monographs - Dietary Supplements
USP35–NF30 Page 4342