Erscheint 4 Ausgaben pro Jahr
ISSN Druckformat: 1521-9429
ISSN Online: 1940-4328
Indexed in
Phycochemistry and bioactivity of ten freshwater algae from Pakistan
ABSTRAKT
Seven blue-green and three green algae were collected from various freshwater habitats of Sindh (Pakistan) during January 1997 - December 1999 and investigated. Their methanol extracts revealed 17 saturated, 2 monoynoic, 12 monoenoic, 5 di-unsaturated, 5 tri-unsaturated and 6 polyunsaturated fatty acids (FAs), β-sitosterol and trans-phytol, which were identified by GC-MS and NMR spectroscopy. Palmitoleic acid was the most commonly occurring FA, while C15:0, C16:0, C14:1, and C18:1 were the next commonly occurring acids. The unsaturated acids were found in larger proportion (46.50-70.46%) than saturated FAs (16.82-39.20%). The blue-green algae did not differ much from green algae of Pakistan in their FA-compositions. Their methanol extracts exhibited poor antibacterial activity but strong antifungal activities. They showed a significant phytotoxic activity but non-significant cytotoxic and insecticidal activities. The extract of Lyngbya hieronymusii enhanced antitumour activity from 20 to 45% with an increase in the concentration of extract. Algae belonging to three phyla (Cyanophyta, Chlorophyta, and Charophyta) revealed differences in their FA-, sterol- and terpene-compositions as well as their bioactivities.