Research Journal of Microbiology1816-4935xxxx-xxxxScience International10.3923/jm.2008.673.682WefkySahar GhobrialMary 122008312Selected species of marine benthic algae belonging to the Phaeophyceae and Rhodophyceae, collected from different coastal areas of Alexandria (Egypt), were investigated for their antibacterial and antifungal, activities against fish pathogens. In vitro screening of organic solvents extracts from the marine macroalgae, Laurencia pinnatifida (Hudson) Stackhouse, Pterocladia capillaceae (Gmelin), Halopteris scoparia (Linnaeus) Kutzing, Stepopodium zonale (J.V. Lamouroux) and Sargassum hystrix var. fluitans Borgesen, showed specific activity in inhibiting the growth of five virulent strains of bacteria pathogenic to fish Pseudomonas fluorescens, Aeromonas hydrophila, Vibrio anguillarum, V. tandara, Escherichia coli and of two fungi Aspergillus flavus and A. niger. Acetone and ethanol extracts of all test macroalgae exhibited antibacterial activity, while acetone extract of S. hystrix exhibited the highest antifungal activity. Macroalgal extracts inhibited bacteria more readily than fungi, besides, the extracts of the Rhodophyceae species showed the greatest activity against current test bacteria rather than fungi. Cluster analysis revealed the general response of the tested pathogens to the action of the different algal extracts. Composition of the most potent algal extracts included acetone extracts of L. pinnatifida, P. capillaceae and S. hystrix and ethanol extract of P. capillaceae was determined using GC-MS. The present study provides the potential of red and brown macroalgae extracts for the development of anti-pathogenic agents for use in fish aquaculture.]]>Abdelhamid, A.M.,20072007Actis, L.A., M.E. Tolmasky and J.H. Crosa,19991999pp: 523-557pp: 523-557Benediktsdottir, E., S. Helgason and H. Sigurjonsdottir,1998Vibrio spp. isolated from salmonids with shallow skin lesions and reared at low temperature.]]>211928Blanch, A.R., M. Alsina, M. Simon and J. Jofre,1997Scophthalmus maximus) larvae.]]>82729734Borowitzka, M.A. and L.J. Borowitzka,1992pp: 179pp: 179Burkholder, P.R., L.M. Burkholder and L.R. Almodovar,19602149156Lu, C., L. Lin and H. Wang,199736454459Cipriano, C.R.,2001Aeromonas Hydrophila and motile Aeromonads Septicemias of Fish. Fish Disease Leaflet 68.]]>Cooper, S., A. Battat, P. Marsot and M. Sylvestre,198329338341Das, B., J. Pradhan, P. Pattnaik, B. Samantaray and S. Samal,2005214550De Nys, R., S.A. Dworjanyn and P.D. Steinberg,19881627987De Rosa, S., Z. Kamenarska, K. Stefanov, S. Dimitrova-Konaklieva, C. Najdenski, I. Tzvetkova, V. Ninova and S. Popoy,2003Corallina mediterranea areschoug and Corallina granifera: Ell. et Soland.]]>58325332DiSalvo, L. H., J. Blecka and R. Zebal,1978Vibrio anguillarum and larval mortality in a California coastal shellfish hatchery.]]>35219221 Eguchi, M., E. Fujiwara and N. Miyamoto,2000Vibrio anguillarum in freshwater environments: Adaptation or debilitation?]]>6126129Ehresmann, D.W., E.F. Deig, M.T. Hatch, L.H. DiSalvo and N.A. Vedros,1977133740Ellis, A.E.,1989El-Masry, H.A., H.H. Fahmy and S.H.A. Abdelwahed,2000514291438Findlay, J.A. and A.D. Patil.,198447815818Fitton, J.H.,20062006pp: 9pp: 9Freile-Pelegrin, Y. and J.L. Morales,200447140146Ghosh, P., U. Adhikari, P.K. Ghosal, C.A. Pujol, M.J. Carlucci, E.B. Damonte and B. Ray,2004In vitro anti-herpetic activity of sulfated polysaccharide fractions from Caulerpa racemosa.]]>6531513157Gomez, D.K., G.W. Baeck, J.H. Kim, C.J. Choresca and S.C. Park,2008203844Del Val, A.G., G. Platas, A. Basilio, A. Cabello and J. Gorrochategui et al.,200143540Hattab, M., G. Culioli, L. Piovetti, S.C. Chitour and R. Valls,2007114317Hornsey, I.S. and D. Hide,1985202125Inglis, V., R.J. Roberts and N.R. Bromage,1993Chapter 6,pp: 109-121pp: 109-121Kellam, S.J., R.J.P. Cannell, A.M. Owsianka and J.M. Walker,1988234547Kent, M.L. and T.T. Poppe,20022002pp: 61-105pp: 61-105Kose, Y.B., G. Iscan, B. Demirci, K.H.C. Baser and S. Celik,2007Centaurea aladagensis.]]>78253254Levin, D.A.,1971105157181Liao, W.R., J.Y. Lin, W.Y. Shieh, W.L. Jeng and R. Huang,2003300433439Lindequist, U. and T. Schweder,20012001pp: 441-484pp: 441-484Mahasneh, I., M. Jamal, M. Kashashneh and M. Zibdeh,1995832326Mayer, A.M. and M.T. Hamann,2002132315339Moreau, J., D. Pesando and B. Caram,1984115215241Newman, D.J., G.M. Cragg and K.M. Snader,20036610221037Ponce, N.M.A., C.A. Pujol, E.B. Damonte, M.L. Flores and C.A. Stortz,2003Adenocystis utricularis: extraction methods, antiviral activity and structural studies.]]>338153165Premnathan, M., H. Nakashima, K. Kathiresan, N. Rajendran and N. Yamamoto,1996In vitro antihuman immunodeficiency virus activity of mangrove plants.]]>103278281Premnathan, M., K. Chandra, S.K. Bajpai and K. Kathiresan,199235321324Reichelt, J.L. and M.A. Borowitzka,1984116158168Del Rio-Rodriguez, R.E., V. Inglis and S.D. Millar,1997Escherichia coli in the intestine of fish.]]>28257264Rodrigues, E., S. Tilvi and C.G. Naik,2004309121127Saharia, P.K. and K.P. Prasad,2001Pseudomonas fluorescens infection in fishes.]]>14293300Salvador, N., A.G. Garreta, L. Lavelli and M.A. Ribera,200771101113Schmidt, A.S., M.S. Bruun, I. Dalsgaard, K. Pedersen and J. Larsen,20006649084915Sridhar, K.R. and N. Vidyavathi,19915455496Tuney, I., B.H. Cadirci, D. Unal and A. Sukatar,200630171175Viso, A.C., D. Pesando and C. Baby,1987304145Vlachos, V., A.T. Critchley and A. von Holy,199942165173Wiik, R., K.A. Hoff, K. Andersen and F.L. Daae,1989Vibrio anguillarum isolated from different fish species.]]>55826831