Nutritional value of Cymodocea nodosa and Posidonia oceanica along the western Egyptian Mediterranean coast

AbstractThe nutritional value of the two seagrasses Cymodocea nodosa and Posidonia oceanica and their potential use as fertilizers were evaluated based on the determination of biochemical content, major and trace element content in the leaves of the two species, occurring in five sites along the western Egyptian Mediterranean coast during summer (2006 and 2009). The total carbohydrates, total proteins and total lipids in C. nodosa were 47.22, 510.44 and 100.78mg/g, respectively, and in P. oceanica 28.98, 607.50 and 40.50mg/g, respectively. The calorific content was 4.03Kcal/g for C. nodosa and 3.93Kcal/g for P. oceanica. N%, P2O5% and K2O% and C:N ratio were 8.45%, 1.21%, 0.81% and 1.50:1 in C. nodosa, respectively, and 10.60%, 2.13%, 0.58% and 1.25:1 in P. oceanica, respectively. The concentrations of trace elements (Cu, Ni, Pb and Zn) in the two species were lower than in composts, while the major element concentrations in C. nodosa coincided with the typical concentrations in composts (P, 530.00; Na, 1044.44; Ca, 2470.00mg/ 100g), respectively, but higher in P. oceanica (P, 930.00; Na, 2765.00; Ca, 3890.00mg/100g), respectively.Cymodocea nodosa only can be potentially used as supplementary powdered organic fertilizer and/or additive compost

Seaweeds agarophytes and associated epiphytic bacteria along Alexandria coastline, Egypt, with emphasis on the evaluation and extraction of agar and agarose

A survey of seaweeds along Alexandria coastline was carried out to choose a suitable agarophyte for extraction and evaluation of the agar and agarose substances, in addition to estimate and identify the epiphytic bacteria associated with these seaweeds which are capable of secreting package of hydrolytic enzymes and hence degrading algal cell walls successfully. A total of 13 algal samples were collected during spring 2012. There were 2 Rhodophytes species; Gelidium crinale and Pterocladiella capillacea, which can be exploited for agar and agarose production. Nine dominant bacterial isolates were associated with the different algal samples; they were identified at genus level as; Alcaligenes sp., Bordetella sp., Acinetobacter sp., Pseudomonas sp.1, Pseudomonas sp.2, Pseudomonas sp.3, Flavobacterium sp., Vibrio sp. and Vigribacillus sp. The most superior species able to secrete a package of degrading enzymes was Vigribacillus sp. that was isolated from P. capillacea harvested from Western Harbor. The total carbohydrate, lipid and protein contents were determined in both P. capillacea and its agar, and in Oxoid agar (a reference commercial material). Some metals (copper, cadmium, lead, zinc, nickel, chrome, ferrous, manganese and arsenic) were also estimated in the 3 mentioned samples. The gel strength, gelling temperature and melting temperature besides the clarity and viscosity of extracted and Oxoid agars showed different patterns. The sulphate content of the extracted agar was slightly higher than that of Oxoid agar, while the pyruvate content showed inverse pattern. The extracted agar FTIR spectrum indicated methylated group, which proved that the agar extracted from P. capillacea is a highly methylated polysaccharide resulting in high gellation.Se realizó un estudio de algas marinas en la costa de Alejandría para seleccionar una agarófita adecuada para la extracción y evaluación de las sustancias de agar y agarosa, además de estimar e identificar las bacterias epifitas asociadas con estas algas capaces de secretar paquetes de enzimas hidrolíticas degradantes de paredes celulares de algas. Un total de 13 muestras de algas se recolectaron durante primavera del 2012. Del total se obtuvieron 2 especies de Rhodophyta; Gelidium crinale y Pterocladiella capillacea, las cuales pueden ser explotadas para la producción de agar y agarosa. Se encontraron un total de 9 géneros de aislados bacterianos dominantes asociados con las diferentes muestras de algas. Estos fueron identificados como; Alcaligenes sp., Bordetella sp., Acinetobacter sp., Pseudomonas sp.1, Pseudomonas sp.2, Pseudomonas sp.3, Flavobacterium sp., Vibrio sp. y Vigribacillus sp. La especie con mayor capacidad de secretar un paquete de enzimas degradantes fue Vigribacillus sp. que fue aislada de P. capillacea cosechado en Western Harbor. Los hidratos de carbono, lípidos y proteínas totales se determinaron tanto en P. capillacea, como en el agar extraido, y agar Oxoid (material comercial de referencia). Además se estimaron algunos metales (cobre, cadmio, plomo, zinc, níquel, cromo, hierro, manganeso y arsénico) en las 3 muestras mencionadas. La resistencia de gel, temperatura de gelificación y fusión, además de la claridad y viscosidad de los extractos y agares Oxoid mostraron diferentes patrones. El contenido de sulfato del agar extraído fue ligeramente mayor que la de agar Oxoid, mientras que el contenido de piruvato mostró patrón inverso. El espectro FTIR del agar extraído indicó grupo metilado, lo que sugiere que el agar extraído de P. capillacea es un polisacárido altamente metilado por tanto de una alta gelificación