KU botany department study highlights medicinal use of seaweeds
KARACHI, Aug 1: Specific species of seaweeds can be used for the treatment of Cutaneous Leishmania, a skin disease, a recent study conducted by a student of the botany department of Karachi University shows.
The study titled Bioactive assessment of selected marine red algae against Leishmania major and chemical constituents of Osmundea pinnatifide was printed this year in the Life Science Weekly, an international publication and in the Pakistan Journal of Botany last year.
The research was the PhD thesis of Dr Sabina Habib who won a gold medal on her presentation based on the study in Sri Lanka in 2006.
According to the research focused on 17 species of seaweeds, extracts from the red algae displayed good inhibitory features against Leishmania major. Seaweed, the study says, is an integral part of the coastal ecology of Pakistan, occurring in an area periodically covered by rising or receding tides along the 1,040-km coastline extending from Sir Creek to Gwadar Bay. Its growth is predominantly observed during the period from September through March.
Seaweeds were collected from the Buleji Coast of Karachi during 2004-2006 and algal species were identified and taxonomically identified in a laboratory. The study established that red algae (Rhodophyta) extracts did influence the metabolic activity of parasite as measured by the ability to inhibit /reduce its growth in vitro.
No previous record on anti-Leishmanial properties of any seaweed from Pakistani coast has appeared in literature. The lead obtained from the search of anti-Leishmanial activity of seaweeds gives a new impetus seeming to validate their use in medicinal therapy, the study says.
“The research shows that the anti-parasitic nature of Pakistani seaweeds that can be utilised as an adjuvant to chemotherapy,” says Dr Habib, adding that major drawbacks of drugs used to treat Leishmania related to toxicity associated with severe side effects.
These problems prompt the development of new safe and effective anti-Leishmanial drugs, she says.
Regarding the nature of the disease, Dr Habib explains that Leishmania is a very virulent tropical disease, second only to malaria.
The cutaneous form of the disease is a painful skin ulcer disease caused by the parasite Leishmania major which is present in many parts of Pakistan and sporadic cases are seen throughout the country, according to her.
“Leishmania is endemic in Pakistan. The biggest outbreak occurred in Sindh districts of Dadu, Jacobabad and Larkana, tribal areas and in parts of Balochistan during 2001-2002 when 11,000 cases were recorded. Some cases of Leishmania were also found in Multan in 1993 and Islamabad in 1995,” she says.
The most promising organic extracts of the red algae analysed in this experiment were Osmundea pinnatifida, Scinaia fascicularis, Melanothamnus afaqhusainii and Gracilaria corticata, she says, adding that protozoan parasites are among the most common pathogens in the world.
They are recognised as the causative agents of some of the most serious tropical diseases in both man and domestic animals, she adds. “Trypanosomiasis, Leishmaniasis, malaria and dengue diseases caused by protozoan can cause massive loss of lives,” she says.
“The research highlights the significance of marine flora, which currently has no commercial value. More research is required that can possibly help us find treatment of many other diseases such as dengue from seaweeds,” she adds.