Sabah Parks Trustee Board member Sukaibin Sumail said the 1ha garden – part of Kinabalu Park, a Unesco World Heritage Site – is home to 12 species of rare nickel-accumulating plants.

He told Bernama certain plants have the natural ability to absorb substances from the soil, including metallic elements such as nickel, a hard, silvery-white metal and one of the most abundant elements in the Earth’s crust and core.

It is widely used in the production of stainless steel and electric-vehicle batteries.

Sukaibin noted that the presence of nickel in soil can pose risks to organisms, including animals and humans.

The garden originally opened in June 2014 as an arboretum, a dedicated area where various tree species are planted and maintained for scientific research, conservation, education, and recreational purposes before being formally documented.

“There are two ways to test for the presence of metals in the leaves of these plants – by using detector paper containing the chemical dimethylglyoxime, or by using a handheld X-ray fluorescence analyser,” said Sukaibin, a botanist.

Among the plants in the garden is the Xylosma Luzonensis, which grows to 3m tall and thrives in open, sunlit areas. “In botany, this plant shows promise as an ornamental species for landscaping, while helping to control soil erosion,” he said.

Studies have yet to be conducted to determine how the plant absorbs nickel, whether entirely naturally or through other mechanisms. Additionally, no scientific data currently supports its potential for pharmaceutical applications.

In July, the Xylosma Luzonensis was showcased at the Borneo Flora Festival in Labuan, during which its leaves – oval-shaped and covered with fine hairs – were tested for the presence of nickel.

Sukaibin, who was present at the exhibition, demonstrated the process by using special paper moistened with water. After a few seconds, the leaves pressed into the paper turned pink, indicating the presence of nickel.

The Raja Permaisuri Agong, Raja Zarith Sofiah, who officiated the programme, was also given the opportunity to test for the presence of nickel through the leaves of the plant.