Comparative antibacterial activities of seaweed extracts from Karachi coast, Pakistan

Six species of green seaweeds [Ulva intestinalis Linnaeus, Ulva fasciata Delile, Ulva lactuca Linnaeus, Chaetomorpha antennina [Bory de Saint-Vincent] Kutzing, Bryopsis pennata Lamouroux, Codium iyengarii Borgesen, Codium shameelii Nizamuddin, Caulerpa scalpelliformis, Caulerpa taxifolia [Vahl] C Agardh], ten species of brown seaweeds [Dictyota dichotoma var intricate [C Agardh] Greville, Dictyota hauckiana Nizamuddin, Padina antillarum [Kutzing] Piccone, spatoglossum variabile Figari et De Notaris, Stoechospermum polypodioides [JV Lamour] J Agardh, Colpomenia sinuosa [Mertens ex Roth] Derbes et Solier, Iyengaria stellata [Borgesen] Borgesen, Jolyna laminarioides guimaraes, Cystoseira indica [Thivy et Doshi] Mairh, Sargassum ilicifolium [Turner] C Agardh] and also ten species of red seaweeds [Dermonema abbottiae Afaq-Husain, Nizamuddin et Shameel, Gelidium usmanghanii Afaq-Husain et Shameel, Gracilaria corticata [J Agardh] J agardh, Gracilaria foliifera [Forsskal] Borgesen, Aspaaragopsis taxiformis [Delile] Trevisan, Cystoclonium purpureum [Hudson] Batters, Botryocladia leptopoda [J Agardh] Kylin, Melanothamnus afaqhusainii Shameel and Osmundea pinnatifida [Hudson] Stackhouse] were collected from the coastal areas of Karachi [Pakistan] and extracted in methanol. These extracts were tested for their antibacterial activity. In comparative study, the brown seaweeds were found to be most active and green seaweeds the least active, while species of red seaweeds occupied and intermediate position