Alimpai is a straggling, climbing shrub. Leaves are extremely variable, the smaller ones ovate-cordate and 2.5 to 7.5 centimeters long, the larger ones, orbicular-cordate and 10 to 18 centimeters long. Margin is coarsely toothed and often has a gland at the sinus or else in the teeth. Racemes are very long, slender, 10 to 18 centimeters long, solitary, and terminal. Male flowers are hairy, with sepals and petals of equal length. Female flowers have sepals that are ovate or oblong, and the petals very minute, subulate, and long-ciliate. Fruit is a capsule, woody, nearly spherical or broadly oblong, 2 to 2.5 centimeters long, terete, or with 6 slender ridges. Seeds are unusually variable, most often dorsally compressed, and slightly rugose.
- In Benguet, Pangasinan, and Rizal Provinces in Luzon, and in Palawan.
- In thickets and ravines at low altitudes, ascending to 400 meters.
- Also reported from India to southern China and southward to Sumatra, Java, Christmas Islands, and Borneo.
- Study yielded crotocaudin, a norditerpene; acogener, teucvidin; and several triterpenoids – taraxerone 2, taraxerol 3, and taraxerol acetate 4.
- Study yielded a new flavone, named crotoncaudatin, from the stems of Croton caudatus Geisel. var. tomentosus Hook., together with nine known analogues: 3,5,6,7,8,3′,4′-heptamethoxyflavone, tangeretin, nobiletin, 5,6,7,4′-tetramethoxy-flavone, sinensetin, kaempferol, tiliroside, kaempferol-3-Orutinoside, and rutin. (3)
- Stem bark yielded triterpenoids (taraxerone, taraxerol and taraxeryl acetate) and norditerpenes crotoncaudin, teuvidin, isocrotocaudin and 5α-stigmastane-3,6-dione.
- Crude ethanolic extract of leaves yielded flavonoids, alkaloids, cyanogenetic glycosides, and phenolic compounds.
- An ethanolic extract showed steroids and/or terpenoids, flavonoids and their glycosides as major constituents. (See study below) (11)
- Qualitative phytochemical analysis of leaves yielded alkaloids, phytosterois, saponins, phlobatannins, cardiac glycosides, flavonoids, phenolics, and terpenoids. (13)
- Study of stems of Croton caudatus Geisel. var. tomentosus Hook. isolated a novel sesquiterpene, crocaudatol (1) along with a known sesquiterpene, oplopanone (2). (21)
- Study of twigs and leaves of C. caudatus var. tomentosus yielded a new 9,10-seco-abietane derivative, crotontomentosin A (1), four new abietane-type diterpenoids, crotontomentosins B–E (2–5), one new ent-halimane-type diterpenoid, crotontomentosin F (6), along with five known diterpenoids (7–11) and one known sesquiterpenoid (12). (see study below) (22)
- Study suggested antibacterial, antioxidant, anticancer, insecticidal, larvicidal, genotoxic, analgesic, anti-inflammatory, antipyretic properties.
- Poultice of leaves applied to sprains.
- Leaves also used for poulticing fevers.
- Young leaf buds are powdered with leaves of Caesalpinia sappan and used for liver diseases.
- Root decoction used for purging, for fevers and colds, and also administered for constipation.
- Traditional healers in India use it for cancer, diabetes, sinusitis, malaria, and piles.
- Used for sprains, arthritis, and liver disorders.
- Leaves used for malaria, cancer, indigestion and diabetes.
- Leaf paste applied for arthritis and treatment of paralysis.
- In India, used for various ailments, including cancer. Root decoction given to women after delivery.
- In Western Ghats, India, reported tribal use of leaves as diuretic and as poultice for sprains; roots used for malaria.
- In China, used for treatment of stomach pain and diseases. Stems used in the treatment of fever, malaria, convulsions, and rheumatic arthritis. (13)
- Veterinary: In China, leaves applied to festering wounds of injured cattle to ward off maggots. (13)
- Basketry: Stems used for making baskets.
• Crotocaudin: Study yielded crotocaudin, a norditerpene occurring as a minor constituent in Croton caudatus Geisel. A cogener, teuvidin was obtained as a major component with several triterpenoids - taraxerone 2, taraxerol 3, and taraxerol acetate 4. (2)
• Croton caudatin: Study yielded a new flavone, croton caudatin, from the stems of C. caudatus Geisel var. tomentosus Hook, together with nine known analogues. (3)
• Antioxidant / Leaves: Study of an ethanol extract of leaves of C. caudatum showed effective antioxidant activity in all of four assay techniques used. (4) Study of various extracts of leaves showed a concentration dependent inhibition of DPPH, OH, O2, NO, and FRAP free radicals. Activity was attributed to the presence of various polyphenols. (15)
• Anti-Cancer Activity: A team of research scholars of Manipur University life sciences department has been able to confirm the name of the claimed anti-cancer plant locally known as Damdawi as Croton caudatus, Geis., a Euphorbiaceae. Study of leaves yielded crotoflorine, crostsparimine and sparsiflorine. Roots and stems yielded dotriacontamol, beta amyrine, and beta sitosterol. (5) (6)
• Larvicidal / Insecticidal: Study evaluated the synergistic effect of extracts of Croton caudatus fruits and Tiliacora acuminata flowers against the larval forms of Culex quinquefasciatus. Results showed highest mortality at 0.5% crude extract and 75 ppm solvent concentration for fruits of CC and flowers of TA individually. Secondary metabolites may be responsible for the larvicidal activity. Results present insecticides of plant origin as an alternative to toxic chemicals. (7)
• Genotoxic / Clastogenic Potential / Leaves: Study of an aqueous extract of leaves injected intraperitoneally in mice showed chromosome aberrations, abnormal chromosome behavior, and synaptonemal complex damages indicating a clastogenic potential. (10)
• Protective Against Experimental Visceral Leishmaniasis / Induction of Proinflammatory Cytokines / Leaves: Study evaluated C. caudatus var. tomentosus Hook against parasitic protozoans in vitro and in vivo. Among five semi-purified extracts of leaves, hexane extracted EA-hexane solvent was the most effective growth inhibitor against Leishmania promastigotes and amastigotes, with significant alteration of biochemical parameters in promastigotes and reduced replication of intracellular amastigotes with concomitant release of NO and pro-inflammatory cytokines. (14)
• Antimicrobial / Leaves: Study evaluated various extracts of leaves for antioxidant and antibacterial activity against human pathogenic gram-negative and gram-positive bacteria and antifungal activity against both human and plant pathogens. All extracts showed varied levels of antimicrobial activity. The ethanolic extract showed good activity against S. aureus and Pseudomonas putida, while a methanolic extract showed good activity against Candida albicans. (16)
• Anticancer / Antioxidant / Analgesic / Leaves: Methanol and aqueous extracts showed potent anticancer activity in vivo (%ILS- 92.5%). An aqueous extract showed an IC50 value 28.36 µg/ml in vitro. The extracts significantly reduced acetic acid and formalin-induced pains in mice. Aqueous extract showed significant DPPH and NO radical scavenging potentials. (17)
• Synergism of C. caudatus Fruits with T. acuminata Flowers against Culex quinquefasciatus: Study investigated the synergistic effect of crude and solvent extract of C. caudatus fruits and T. acuminata flowers against the larval form of Culex quinquefasciatus. The combined form of C. caudatus fruits and T. acuminata flowers showed good bioactive potentiality against Cx. quinquefasciatus larvae due to synergism of the plant extracts. The plant extract seemed ecologically safe to use in field conditions. (18)
• Antinociceptive / Anti-Inflammatory / Antipyretic / Leaves: Study of an ethanolic extract of leaves showed 47% protection in carrageenan-induced edema. The extract showed dose-dependent reduction in nociception. Naloxone reversed the antinociception of the extract in hot plate testing, indicating morphinomimetic properties. The extract also decreased rectal temperatures in yeast-induced pyrexia in rats. An ethanolic extract produced 47% protection in carrageenan-induced edema. (19)
• Diterpenoids / Cytotoxicity / Twigs and Leaves: Study of twigs and leaves of Croton caudatus var. tomentosus yielded crotontomentosins A-F (1-6), along with five known diterpenoids (7-11) and one known sesquiterpenoid (12). Compounds 1-4 and 11 exhibited moderate to weak inhibitory activity against proliferation of Hela, Hep G2, MDA, MDA-MD-231, or A549 cell lines selectively. (see constituents above) (22)