''Thunbergia laurifolia'', the laurel clockvine or blue trumpet vine, is native to

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

and

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

and the

Indomalayan realm The Indomalayan realm is one of the eight biogeographic realms. It extends across most of South and Southeast Asia and into the southern parts of East Asia. Also called the Oriental realm by biogeographers, Indomalaya spreads all over the Indi ...

, the species occurs from

Indochina Mainland Southeast Asia, also known as the Indochinese Peninsula or Indochina, is the continental portion of Southeast Asia. It lies east of the Indian subcontinent and south of Mainland China and is bordered by the Indian Ocean to the west an ...

to Malaysia.

Description

''Thunbergia laurifolia'' leaves are opposite, heart-shaped with serrated leaf margin and taper to a pointed tip. This species is very similar in appearance to '' T. grandiflora'', but has longer, thinner leaves and its young stems and leaves are hairless. The flowers are not scented and borne on pendulous inflorescences. The hermaphrodite flower is trumpet-shaped with a short broad tube, white outside and yellowish inside. The corolla is pale blue in colour with 5–7 petals, one larger than the others. Plants flower almost continuously throughout the year with flowers opening early in the morning and aborting in the evening of the same day. Carpenter bees are frequent visitors, creeping into the flowers for pollen and nectar while black ants are present probably as nectar scavengers. The plant develops a very tuberous root system.

Uses

Cultivation

''Thunbergia laurifolia'' is a popular

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that i ...

in tropical gardens. It is a long-blooming vine in cultivation. Propagation is from stem cuttings or shoots from the tuberous roots. It is a fast-growing perennial herbaceous climber. It has become an exotic weed in many tropical countries.

Teas and medicinal

In Malaysia, juice from crushed leaves of ''T. laurifolia'' are taken for menorrhagia, placed into the ear for deafness, and applied for poulticing cuts and boils. In Thailand, leaves are used as an antipyretic, as well as for detoxifying poisons. It is locally known as akar tuau in Malaysia and (รางจืด) in Thailand. Several Thai herbal companies have started producing and exporting tea. ''T. laurifolia'' is used in Thailand for patients in drug addiction treatment, and two studies on

lab rat A laboratory rat or lab rat is a brown rat of the subspecies ''Fancy rat, Rattus norvegicus domestica'' which is bred and kept for scientific research. While Animal testing on rodents, less commonly used for research than mice (see laboratory mo ...

s show ''T. laurifolia'' may stimulate

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...

production.Thongsaard W, Marsden C. Effect of Thunbergia laurifolia extract on extracellular dopamine level in rat nucleus accumbens. J Med Assoc Thai. 2013 Jan;96 Suppl 1:S85-9. PMID: 23724461.Thongsaard W, Marsden CA. A herbal medicine used in the treatment of addiction mimics the action of amphetamine on in vitro rat striatal dopamine release. Neurosci Lett. 2002 Aug 30;329(2):129-32. doi: 10.1016/s0304-3940(02)00658-4. PMID: 12165394.

Chemistry

Iridoid Iridoids are a type of monoterpenoids in the general form of cyclopentanopyran, found in a wide variety of plants and some animals. They are biosynthetically derived from 8-oxogeranial. Iridoids are typically found in plants as glycosides, mos ...

glucoside A glucoside is a glycoside that is derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes. The name was o ...

s have been isolated from ''T. laurifolia''. Microwave-dried leaves displayed stronger antioxidant properties than fresh leaves. The antioxidant properties of the infusion from microwave-dried leaves is higher than the commercial tea from Thailand.

Invasive species

''Thunbergia laurifolia'' can become an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

where escaping from ornamental garden uses into native

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s in supportive climates. Because it is a fast-growing perennial plant it has become an

escaped exotic Escape or Escaping may refer to: Computing * Escape character, in computing and telecommunication, a character which signifies that what follows takes an alternative interpretation ** Escape sequence, a series of characters used to trigger some so ...

and

noxious weed A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or liv ...

in many tropical countries The plant has become a weed found in the

Cerrado The ''Cerrado'' (, ) is a vast ecoregion of tropical savanna in eastern Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais, and the Federal District. The core areas of the Cerrado biome are t ...

vegetation Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic character ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

and in tropical areas of Australia.

References

External links

www-weeds.au - ''Thunbergia laurifolia''
{{Taxonbar, from=Q514393 laurifolia Flora of India (region) Flora of Indo-China Flora of Malesia Garden plants of Asia