Pereskia bleo is a common medicinal plant grown in Singapore. Locally known as the ‘Seven Star Needle’ (qi xing zhen), this plant is a member of the cactus family. The genus was named in honour of Nicolas Fabre de Peiresc, a French botanist of the 16th century.
However, this cactus is a leafy cactus that is not a desert-adapted plant like many other leafless cacti we are familiar with – it grows in the shady and moist forests of Central America. This probably explains why specimens grown in hot and sunny spots often become yellow and stunted. Desert cacti have lost all their leaves to avoid excessive loss of water via transpiration.
It may seem strange at first that it can be a cactus with leaves. In fact, this genus of plants is determined one of the two genera from which all other cacti evolved. If one look closely at the stem of the Pereskia, a tell-tale feature that it is a cactus is evident via its cluster of spines grow from specialized structures called areoles which is a feature that all true cactus species have.
Some English common names of Pereskia bleo include Leaf Cactus, Rose Cactus and Wax Rose. These common names somewhat describe some characteristics of this plant. Pereskia bleo is a true cactus and it is one with leaves unlike many others that are commonly grown as houseplants. The latter two common names very well describe its rather large and highly ornamental flowers with multiple thick orange petals that are arranged in almost the same manner as seen in roses. After flowering, plants produce interesting, funnel-looking fruits which ripen into a bright orange colour.
Pereskia bleo can grow into a small, woody but prickly tree of about 2 m in height. It can take relatively hard pruning which can be employed to help keep it small and manageable. Its prickly nature can be exploited for using it to make a living fence – individual plants can be planted at regular intervals to form a prickly screen to deter intruders. Plants are propagated most easily via stem-cuttings. It is best grown in well-draining soil rich in organic matter and kept moist at all times. As mentioned above, unlike other leafless cacti species, this plant is not exactly a succulent and hence not drought-tolerant.
The leaves of this plant are eaten raw by locals here with the belief that it can prevent or cure one of cancer. Leaves are relatively blant to taste. Solid scientific evidence to support this belief is still not available as limited scientific studies have been done to date and all are still confined to the petri-dish. Reference of these studies are given below:
- Tan ML, Sulaiman SF, Najimuddin N, Samian MR and Muhammad TS. 2005. Methanolic extract of Pereskia bleo (Kunth) DC. (Cactaceae) induces apoptosis in breast carcinoma, T47-D cell line. J Ethnopharmacol, 96(1-2):287-94.
- Er HM, Cheng EH and Radhakrishnan AK. 2007. Anti-proliferative and mutagenic activities of aqueous and methanol extracts of leaves from Pereskia bleo (Kunth) DC (Cactaceae). J Ethnopharmacol, 113(3):448-56.
- Malek SN, Shin SK, Wahab NA and Yaacob H. 2009. Cytotoxic components of Pereskia bleo (Kunth) DC. (Cactaceae) leaves. Molecules, 14(5):1713-24.