Which plant seed is a laxative and anti-inflammatory, containing ricin?

• A. Ricinus communis
• B. Rauwolfia serpentina
• C. Rosmarinus officinalis
• D. Sambucus nigra

Answer: (A)

Ricinus communis, the castor bean, matches this description because its seeds contain ricin, a potent toxin. Castor oil, derived from these seeds, acts as a stimulant laxative, and topical preparations of castor oil are traditionally used for their anti-inflammatory effects. This combination—laxative action from the oil and anti-inflammatory use of the oil—occurs in castor bean preparations, and the presence of ricin in the seeds is the identifying feature.

The other plants listed do not fit: Rauwolfia serpentina is used for cardiovascular and mental health indications due to alkaloids like reserpine, not for laxative or ricin-containing properties. Rosmarinus officinalis (rosemary) has anti-inflammatory constituents but does not contain ricin and is not known for a laxative seed. Sambucus nigra (elderberry) has anti-inflammatory and immune-modulating uses but again does not contain ricin and is not a laxative seed.

So, the seed that is laxative and anti-inflammatory and contains ricin is Ricinus communis.