Lantana

The plant

Lantana camara is a species of flowering plant in the verbena family (Verbenaceae), native to the tropics of the Americas. Its native range is Central and South America. It is a perennial shrub that typically grows to around 2 metres tall. The leaves are broadly ovate, opposite and simple. The small tubular flowers are arranged in clusters. They can be white, yellow, orange, red, pink or multi-coloured.

Spread and invasiveness

It first spread out of the Americas when Dutch explorers brought it to Europe, where it was cultivated widely. Lantanas were brought to Australia as an ornamental garden plant in 1841. They were brought to India by the British around 200 years ago, and became invasive there as well. In Ethiopia the plant was first introduced for ornamental purposes because of its attractive fragrance and flower colours. It has become naturalised in around 60 tropical and subtropical countries worldwide. It can form dense thickets. It can also outcompete native species, which leads to a reduction in biodiversity.

Chemistry of the essential oil

The essential oils hydrodistilled from the plant are dominated by sesquiterpenes such as (E)-β-caryophyllene and α-humulene. Some monoterpenes such as thymol, sabinene and α-pinene are also present. In oils from Côte d'Ivoire, the eighty-four compounds identified accounted for 84.4-99.1% of the oils. In the Ivorian leaf oils, (E)-β-caryophyllene made up 24.4-39.9% and α-humulene 10.1-20.5%. The composition of the oil varies widely with the plant's growth area. Major compounds reported are sesquiterpenes such as (E)-β-caryophyllene, α-humulene, davanone and germacrene D. In oils from northeast India (Dibrugarh), the main compound was cis-davanone at 47.8%. In oils from Benin, the main compounds were sabinene (38.81%) and 1,8-cineole (28.90%). In the Ivorian leaf oils the thymol proportion reached 16.5% in July and 18.4% in August 2015, and was lower than 2.3% in the other months. Stem, flower and fruit oils were more concentrated in thymol than leaf oils.

Uses

Lantana camara is commonly used as an ornamental plant, and also in traditional medicine in many countries. Leaf and flower essential oils displayed high antioxidant, anti-inflammatory and insecticidal activities.