The Star, Malaysia : Langkawi

Tuesday, May 06, 2003

Langkawi : Lichens

OFTEN overlooked or ignored, unique life forms known as lichens are attracting new attention for their medicinal, decorative and pollution-detecting properties.

In Langkawi, Dr Amir Feisal Merican and two students amassed 100 specimens. “The lichens collected at the top of Gunung Mat Cincang are very interesting. They were colourful and looked very different from lichens seen in lowlands. The higher we climbed, the more diverse the lichens but the greatest abundance of lichens was found in the Lubuk Sembilang area.”

Despite their plant-like forms, lichens are not plants. Often called tiny ecosystems, they are actually compound organisms made up of two, or even three, very different partners. The dominant partner in the lichen symbiosis is a fungus, with a colony of algae or cyanobacteria – sometimes both – supplying food by photosynthesis. The fungus provides the algae with protection and moisture.

“Lichens have not really been studied in Malaysia at the moment,” says Amir, an environment biotechnologist from Universiti Malaya. “They are a forgotten treasure.”

Lichens can tolerate almost any environment, from tropical rainforest to arctic conditions. They can grow almost anywhere under favourable conditions: on tree trunks, leaves, soil, rocks, highway signs, roof shingle, walls, even on the backs of Galapagos tortoises.

Lichens have been recognised as a rich source of biologically active metabolites since the beginning of the 20th century. Because of their sensitivity to different gaseous pollutants, particularly sulphur dioxide, lichens are useful indicators of air quality. They act like sponges, taking up pollutants that come their way. By analysing lichens chemically, scientists can tell what is in the air.

Lichens also contain substances which can be turned into natural dyes and antibiotics. Some lichens contain phenolic acids and essential oils that produce fragrant odours in scented soaps and help fix the aroma of fine perfumes.