Gen info
- Decalobanthus is a genus of flowering plants in the family Convolvulaceae.
- Decalobanthus peltatus is a species of flowering vine in the morning glory family, Convolvulaceae.
- Etymology: The genus name Decalobanthus derives from Greek words deca meaning "ten", lobos meaning "lobe" and anthos meaning "flower". The specific epithet peltatus derives from Latin, meaning "shield-shaped", referring to the petiole attachment of the leaf underside.
- The species was previous known as Merremia peltata but was transferred to Decalobanthus to better reflect its morphology and molecular structure. (Wikipedia)
- As an invasive species in island habitats, D. peltatus can completely cover tree, smothering and killing large areas of native forest, resulting in death of trees and loss of forests, lees food for native birds and fruit bats, while also possible increasing soil erosion, increased sedimentation and death of coral reefs. (14)

Botany
- Bulakan is a coarse and widely spreading woody vine. Stems are 5 or more centimeters thick, and porous. Leaves are alternate, smooth, somewhat rounded, about 20 centimeters wide, those toward the ends of the branchlets being much smaller, heart-shaped at the base, pointed at the tip. Peduncle grows solitary from each of the upper leaf axils, erect and longer than the leaves. Flowers are large, golden-yellow, few to many, or clustered. Sepals are smooth, thick, oblong, 2 centimeters long. Corolla has a wide limb.

Distribution
- Native to the Philippines. (6) (13)
- Common in secondary forests at sea level and low and medium elevation.
- In Luzon: Bataan, Cagayan, Camarines, Isabela, Laguna, Quezon, Sorsogon, Zambales; In Mindanao: Davao, Misamis Oriental, Zamboanga del Norte, Zamboanga del Sur, Sulu, Tawi-tawi; in the Visayas: Bohol, Cebu, Leyte . (13)
- Also native to Andaman Is., Bismarck Archipelago, Borneo, Christmas I., Comoros, Cook Is., Fiji, Jawa, Lesser Sunda Is., Madagascar, Malaya, Maluku, Mauritius, New Guinea, Nicobar Is., Niue, Queensland, Rodrigues, Réunion, Samoa, Society Is., Solomon Is., Sulawesi, Sumatera, Tanzania, Thailand, Tonga, Tubuai Is., Vanuatu, Wallis-Futuna Is. (6)
- In some places considered a troublesome vine, invading forest strands, strangling and smothering vegetation and trees. (11)

Constituents
- Phytochemical screening of leaves yielded terpenoid, steroid, saponin and phenolic compound. (see study below) (9)
- Phytochemical screenng of methanolic crude extract of leaves yielded bioactive compounds including alkaloids+, falvonoids+++, saponins+++, steroids+, and tannins +++. (see study below) (15)

Properties
- Laxative, anthelmintic.
- Studies have suggest Antimicrobial, cytotoxic activities.

Parts used
Stems, leaves, juice.

Uses
Edibility
- In Malaya, tubers reported to be edible, but may have a purgative effect.
Folkloric
- In the Philippines, sap from the stem taken as anthelmintic. Infusion of roots used for chills. Tubers used to treat uterine hemorrhage.
- The Ati tribe in Malay, Aklan, Philippines, apply latex from stems to cuts and wounds. (16)
- Juice of the stems taken for coughs and diarrhea; also used for sore eyes.
- Leaves used for washing the hair.
- Leaves used stomach pain, skin sores, and inflammation.
- Leaves applied as poultices for superficial ulcers and wounds.
- Leaves applied as maturative for inflammation of the breasts.
- In Vanuatu, new mothers are encourage to drink a lot of coconut water, to which sap of Merremia peltata may be added. (1)
- In Fiji, leaf decoction used to treat boils, infections, and appendicitis. Decoction of roots used to treat stomach muscle rigidity. Drink made from the juice of leaves used for hernias.
- In Papua, New Guinea, leaf, stem and sap used on wounds, sores and swellings.
- In Manus Island, stem sap used on cuts and young leaves applied to sores. On Buin, used for filariasis, elephantitis of scrotum, cut wounds, fever, rhinitis, boils and centipede bites. In Siwai, used for eye inflammation and bullet wounds. (7)
- In Fiji and India, diluted sap from the young leaves used as eye or ear drops
- Sundanese use the extract for stomachaches.
- In Indonesia, leaves used for washing hair, believed to improve growth and prevent hair loss.
- In Serampas, Jambi Indonesia, used for treating cough. (8)
- To facilitate childbirth, Vanuatu women drink juice squeezed out of ten leaves each of M. odorata and m peltata, and to improve lactation, sap of the leaves added on to coconut milk.
- In Indo-China and India, sap from stem are used as laxative. In Fiji, decoction of leaves used to treat boils, infections and appendicitis. Decoction of roots used to treat stomach muscular rigidity. Juice of leaves use for the treatment of hernia and the heated leaves applied as poultice. In Papua New Guinea, stem or sap used for wounds, sores, and swellings. (4)
- In Papua New Guinea, sap of fresh cut leaves used for boils, sores, ulcers, fresh cuts and wounds. Stems used for fever and malaria. (10)
- Punan people of Sarawak, Borneo apply morning dew on flowers for red eye, infections and inflammations. (15)
- In Mayotte, Comoros, sap used as depilatory. (17)
Others
- Tying: In the Philippines, stems sometimes used for tying.
- Agroforestry: Sometimes utilized to provide rapid ground cover to reduce erosion and nutrient losses. (11)

Studies
• Antimicrobial: Leaves yielded alkaloids and showed antimicrobial activity. (4)
• Anti-HIV Activity: A MeOH extract showed anti-HIV activity, inhibiting HIV-1 reverse transcriptase, and gp120-CD4 binding in vitro. (4)(5)
• Cytotoxicity / Leaves: Study evaluated the cytotoxic effects of methanol extract and fractions of leaves of Merremia peltata by Brine Shrimp Lethality Method. The methanolic extract showed cytotoxicity with LC50 19.68 ppm, n-hexane fraction 22.03 ppm, ethyl acetate fraction 130.92 ppm and methanolic fraction 532.11 ppm. (9)
• Antibacterial / Leaves: Phytochemical screening of a leaf extract yielded alkaloid, steroids and flavonoids. Ethanol and and water leaf extract showed inhibitory activity on Gram-posiitive bacteria S. aureus and B. subtilis and Gram-negative bacteria E. coli and P. aeruginosa. (12)
• Toxicity Study / Leaves: Study evaluated the embryotoxic and teratogenic effects of crude leaf extracts of D. peltatus on duck embryos. Brine shrimp lethality testing showed concentration related mortality values, with the ethyl acetate extract showing highest % mortality followed by hexane extract, with LC50s of 14.54 ppm and 26.30 ppm respectively. Duck embryos treated with highest concentration of extract exhibited malformations, growth retardation, and hemorrhages on external body surfaces. Results suggest potential for risk when taken in significant dosages.(15)

Availability
Wild-crafted.

Additional Sources and Suggested Readings
(1)
Maternity and medicinal plants in Vanuatu I. The cycle of reproduction / G. Bourdy and A. Walter / Journal of Ethnopharmacology, 1992; 37(3): pp 179-196
(2)
CONVOLVULACEAE / Merremia Dennst. ex Endl. / Gen. Pl., Suppl. 1: 1403 (1841).
(3)
Merremia peltata / Common names / PIER (Pacific Island Ecosystems at Risk)
(4)
Merremia Dennst. ex Endl. / Mansur, M., 2001. / Record from Proseabase. van Valkenburg, J.L.C.H. and Bunyapraphatsara, N. (Editors).
(5)
Medicinal plants as a source of therapeutic agents against HIV infection / U. K. Patil, V. K. Dixit* / JOURNAL OF NATURAL REMEDIES
(6)
Decalobanthus peltatus / KEW: Plants of the World Online
(7)
An ethnobotanical survey of medicinal plants used in the Siwai and Buin districts of the Autonomous Region of Bougainville / Julie Waruruai, Beuluah Sipana, Michael Koch, Louis R. Barrows, Teatulohi K. Matainaho, and Prem P Rai / J Ethnopharmacol. 2011 Nov 18; 138(2): 564–577. / doi: 10.1016/j.jep.2011.09.052
(8)
Uras: Medicinal and Ritual Plants of Serampas, Jambi Indonesia / Bambang Hariyadi and Tamara Ticktin / Ethnobotany Research & Applications, April 15, 2012
(9)
Extraction, fractionation and Cytotoxicity Test of Merremia peltata (L.) Merr., (Fam. Convolvulaceae) Leaves / Yohannes Alen , Puspita Sari , Yufri Aldi , Yulianis , Shuhei Nakajima , Niomichi Baba, and and Akmal Djamaan / Scholars Research Library, Der Pharmacia Lettre, 2016, 8 (11):48-52
(10)
An ethnobotanical survey of medicinal plants used in the East Sepik province of Papua New Guinea / Michael Koch et al / Journal of Ethnobiology and Ethnomedicine201511:79 / DOI: 10.1186/s13002-015-0065-8
(11)
Merremia peltata / Global Invasive Species Database
(12)
Phytochemical and antibacterial properties of the ethanolic leaf extract of Merremia peltata (L.) Merr. and Rubus spp. /  Kristine Jay B Perez, Mark Anthony Israel Jose, Ma. Reina Suzette Madamba, Edgardo C Aranico / Advances in Environmental Biology, Aug 2015; 9(19): pp 50-56 / eISSN: 1998-1066 / pISSN: 1995-0756
(13)
Convolvulaceae: Decalobanthus peltatus / Co's Digital Flora of the Philippines
(14)
Decalobanthus peltatus / Wikipedia
(15)
Ethnobotanical Survey of Medicinal Plants Used by the Punan People of Sarawak, Borneo: A Conservation Perspective / Keeren Sundara Rajoo, Philip Lepun et al / Tropical Conservation Science, 2025; Vol 18: pp 1-13 / DOI: 10.1177/19400829251328561
(16)
Ethnobotanical documentation of medicinal plants used by the Ati tribe in Malay, Aklan, Philippines / Cecillia Salugta Cordero, Antonio Ligsay, GJD Alehandro / Journal of Complementary Medicine Research, 2020; 11(1) / DOI: 10.5455/jcmr.2020.11.01.20
(17)
Exploring traditional cosmetic flora from Comoros islands: An ethnobotanical survey in Mayotte / Oumaynou Darouceche, Abassi Dimassi, Cedric Bertrand, Francois Chassagne / Heliyon, 2024; 10(15): e35322 / DOI: 10.1016/j.heliyon.2024.e35322

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