Decalobanthus mammosus (Lour.) A.R.Simões & Staples

Decalobanthus mammosus or bidara upas is not native to Indonesia, originating instead from India, the Andaman Islands, and Indochina, but has long been cultivated in Java, Bali, Maluku, and Madura as a medicinal plant and food source from its tuber. Its status is classified as rare according to the 2003 Indonesia Biodiversity Strategy and Action Plan, yet bidara upas remains popular as an ingredient in traveling herbal medicine (jamu gendong) and the small-scale traditional medicine industry, while its satin-sheened fiber is used to make cloth.

Grows wild in forests, sometimes planted in yards near fences. Grows well in tropical regions from lowlands up to elevations of 250 m asl. On the island of Java, bidara upas grows at elevations >500 m above sea level.

• Tubers clustered underground, resembling sweet potato. Tuber skin color yellowish brown, skin thick and exudes white sap, turning brown when dry.
• Stem small, somewhat slippery to the touch, and somewhat dark in color.
• Leaves single, long-petiolate, heart-shaped, margin entire, tip acuminate, 5-12 cm long, 4-15 cm wide, dark green in color.
• Flowers bell-shaped, white, 7-8 cm long, with 4 petals. Inflorescence forked, umbrella-shaped, clustered 1-4 flowers.

Propagated by stem cuttings or by planting tubers or tuber sections.

Oxidase (in its sap), flavonoids, quinones, phenolic compounds, triterpenoids, and steroids.

Reduces fever, treats respiratory disorders, digestive disorders, wounds from snake bites or burns, diabetes, cough, hoarseness, diphtheria, sore throat, lung inflammation (pneumonia), appendicitis, typhoid, constipation, bloody and mucous stools, vomiting blood, leprosy, melanoma, syphilis, bladder stones or kidney stones, used in cancer treatment therapy, addresses food poisoning, relieves swelling, promotes breast milk flow (external use), acts as a laxative and cooling agent. Has anti-inflammatory, analgesic (pain relieving), antidote (neutralizing poison) activity.

Blanar, Widara upas (Jawa), Hailale (Ambon).