Lapnis is a coarse, erect, simple or branched, annual herb, 0.5 to 2 meters high, covered with hairs. Leaves are orbicular, 5 to 15 centimeters in diameter, obscurely and shallowly lobed, finely toothed and somewhat heart-shaped at the base. Flowers are borne in axillary and terminal heads. The calyx-lobes are short, and slenderly pointed at the tip. The petals are yellow, imbricate, about 1 centimeter long.
- Common weed in open, waste places in Nueva Viscaya, La Union, Pampanga, Rizal, Cavite, Laguna Provinces and Manila in Luzon.
- Native of tropical America.
- Planted as a fiber plant in India.
- Now pantropic.
- Phytochemical screening yielded alkaloids, flavonoids, tannins, phlobatanin, terpenoid, saponin, and glycosides. (6)
- Fat obtained from shade dried plant was saponified; the unsaponifiable matter was isolated and identified as ß-sitosterol. (8)
- Roots yield phenols, tannins, carbohydrates, saponins, and flavonoids.
- HPLC analysis of roots for flavonoid
contents detected (mg/g concentration): gallic aid 20.0, caffeic acid 1.0, rutin 0.1, quercetin 10.0, ferulic acid 1.0. Stem yielded gallic acid 30.0, with others below detection limit. Leaves yielded rutin 10.0 and ferulic acid 10.0, with the three other flavonoids below detectable limit. (14)
- Various solvent extracts of root, stem, and leaf dry powder yielded alkaloids, anthocyanoides, coumarin, flavonoids, phenol, protein, saponins, tannins, and terpenoids. (see study below) (16)
- Studies suggest anti-viral, hepatoprotective, antiulcer, anti-epileptic, corrosion inhibition, antioxidant, antdiarrheal, hepatoprotective properties.
Flowers, leaves and roots.
• Decoction of roots and leaves considered an emollient, used as an enema and bathing purposes.
• Roots used as traditional remedy for many diseases: diarrhea, convulsion, inflammation, fever, wound healing.
• In Antilles, used as an emollient.
• In West Bengal, India, used for infertility -- raw fruits given daily during the menstrual period, for 3 months.
• In Indian traditional medicine, used for treatment of epilepsy and inflammation.
• In the Krishna district of India, leaf paste is used as an external ointment for treating skin eruptions.
• In India's Akola district, plant used for gastric disorders and jaundice.
• Fiber: Bast is strong and used in rope making. Fiber is excellent, 8 to 9 feet long, considered as strong and just slightly inferior to jute.
• Antiviral Activity / Stems and Leaves: In a study of forty-seven ethanol crude extracts of 42 plants for antiviral activity against Foot and Mouth Disease type O, the leaves and stems of Malachra capitata showed low antiviral activity. (1)
• Anti-Ulcer Activity / Roots: Study evaluated the anti-ulcer activity of aqueous extract of roots of Malachra capitata against pylorus ligation and ethanol induced gastric ulcer in rats. Results showed significant anti-ulcer activity in both models, with gastric anti-secretory effect in pylorus-ligated rats and gastric cytoprotective effect in ethanol induced gastric ulcers. Ranitidine and misoprostol were used as standard drugs. (4)
• Corrosion Inhibition / Leaves: Study evaluated an extract of leaves for corrosion inhibit on of mild steel in 1N H2So4. Weight loss results showed the extract of M. capitata leaves is an excellent corrosion inhibitor. Adsorption of active molecules led to the formation of a protective layer on the surface of the mild steel. (5)
• Anti-Epileptic Activity: Study evaluated and aqueous extract of M. capitata showed anti-convulsant activity on MES (Maximum Electroshock) and PTZ (Pentylenetetrazole) induced seizure models in albino Wistar rats. Anticonvulsant activity may be due to potentiation of GABA activity. (10)
• Corrosion Inhibition / Leaves: Extract of M. capitata leaves was investigated as corrosion inhibitor of mild steel in 1N H2SO4. Results showed the leaves of MC to be an excellent corrosion inhibitor, with a mixed mode of inhibition, with adsorption of active molecules providing formation of a protective layer on the surface of mild steel. (9)
• Toxicity Study / Roots: Acute toxicity study of roots in rats showed the extract to be safe at doses of 2000 mg/kg body weight orally per OECD guidelines. In chronic study, no significant changes were observed with hematological, hepatic, and renal parameters. (12)
• Antidiarrheal / Roots: Study evaluated an aqueous extract of roots for antidiarrheal activity using castor oil-induced diarrhea, enteropooling and small intestinal transit model in rats. Results showed significant (p<0.001) reduction of castor oil-induced frequency and enteropooling. At 200 and 400 mg/kg, there was significant inhibition (p<0.001) in castor oil-induced charcoal meal transit. (12) (19)
• Erythrocyte Protective Activity / Antioxidant: Study evaluated the antioxidant activity of aqueous extract of M. capitata in rats with carbon tetrachloride (CCl4)-induced erythrocyte damage. Results showed the extract protected against the loss of functional integrity and membrane lipid alteration in RBCs induced by oxidative stress, together with inhibition of accumulation of lipid peroxidation products. (13)
• Flavonoids / Antioxidant: HPLC studies of methanol extracts of root, stem and leaf samples yielded appreciable amounts of flavonoid gallic acids (root and stem), quercetin (root), rutin and ferulic acid (leaf). (see constituents above) (14)
• Hepatoprotective: Study evaluated an aqueous extract of M. capitata showed significant protection against CCl4 induced toxicity model in male Wistar albino rats. (12)
/ Stem and Roots: Study evaluated ethanol extracts of leaf, stem, and root of Malachra capitata for antimicrobial activity against Micrococcus sp, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium. Stem and root extracts were active against all test organisms. Leaf extract was effective against Micrococcus and E. coli only. (15)
• Antimicrobial: Study of ethanol extracts of leaf root, stem, and leaf showed potential activity against bacteria (E. coli, P. aeruginosa, B. subtilis) and fungi (C. albicans, C. paraapsolisis, and A. niger). (see constituents above) (16)
• Antioxidant / Roots: Study evaluated an aqueous extract of roots for antioxidant activity using DPPH scavenging and reducing power assays. Results showed significant dose dependent inhibition of DPPH activity. (17)
• Silver Nanoparticles / Antibacterial / Leaf: Study reports on the green, eco-friendly and convenient method of silver nanoparticles synthesis using n-hexane extract of leaf as reducing agent. The green synthesized AgNPs showed excellent antibacterial activity against all tested bacterial strains viz. B. subtilis, M. luteus, S. aurues, and P. aeruginosa. (18)