Guma-guma is an erect, annual, hairy herb growing to a height of 30 to 90 centimeters. Leaves are linear or elliptic-lanceolate, 5 to 7.5 centimeters long, blunt at the tip, and toothed at the margins. Whorls of many flowers are 1 to 1.5 centimeters in diameter. Calyx is 5 to 7 millimeters long, and obliquely turbinate, with minute teeth, erect or spreading horizontally.
- I n open grasslands at low altitudes in Nueva Viscaya and Bataan Provinces in Luzon; and in Panay and Mindanao (Lanao and Davao).
- Also occurs In tropical Asia to Malaya.
- On distillation, yields a small amount of essential oil.
- Decoction of herb boiled with soda solution emits a strong odor; when condensed, the vapor yields ammonia and a volatile alkaloid in the distillate.
- Considered a stimulant and antirheumatic.
Leaves, flowers, roots.
- Herb has a bitter taste; used as flavoring or pot herb.
- In Bali, sometimes used as flavoring.
- Used for coughs, toothaches and abdominal pains.
- In China, used for coughs.
- In China and Malaya, poultice of leaves used for wounds and sores.
- Poultice of leaves also used for itches, headaches and vertigo.
- In Reunion, used as stimulant and antirheumatic.
A decoction of leaves and Nigella seed or the fresh juice of tumeric and rice, used for ulceration.
- Juice of leaves used for headaches and colds.
- In Ceylon, plant used for mild fevers associated with indigestion; also, for pain caused by intestinal worms.
- Leaves used for itches.
- Bitter roots and bitter and pungent leaves used for skin diseases and for scabies.
- Infusion used as insecticide.
- In Malaysia, leaves taken as sedative and for wound healing. Entire plant rubbed on the abdomen after child-birth. Leaves used as anthelmintic.
- In India, used for fever, scorpion and snake bites. Leaves and flowers used for jaundice.
- In Sri Lanka, a principle vermifuge ingredient. Used for anorexia, flatulence, colic; in mixture, used to treat malaria.
• Antibacterial / Photoactivity: In a study of 32 plants species collected from serpentine (ultramafic) soils in Sri Lanka and screened for antimicrobial properties, L. zeylanica showed photo-mediated activity against S. aureus and B. subtilis. L. zeylanica showed population-level variation in photoactivity. Study suggests plants from serpentine environments may have altered antimicrobial activities compared to non-serpentine environments, and that attention is needed in deciding on the substrate and habitat when collecting plants to test for antimicrobial properties.
• Essential Oil / Antioxidant / Antibacterial: Study of essential oil showed the major components were: oleic acid, hexadecanoic acid, 1-octenen-3-oil, caryophyllene, etc. The essential oil showed scavenging antioxidant activity. Antibacterial activity showed inhibition of test bacterial growth, especially E coli and Salmonella enteriditis.