Chemical composition and trace elements in the samples from exoskeletons of the lobster Panulirus argus and its possible use in agriculture

• Published in: Revista CENIC. Ciencias químicas Vol. 41; no. 2; pp. 99 - 104
• Main Authors: Ramirez-Arrebato, MA, Rodriguez, A T, Alfonso, JA, Azocar, J, Vazquez, Y, Alfonso-Hernandez, L, Peniche-Covas, C
• Format: Journal Article
• Language: Spanish
• Published: 01.01.2010
• Subjects: Marine; Panulirus argus; ASW, Caribbean Sea, Greater Antilles, Cuba
• ISSN: 1015-8553; 2221-2442

Samples from Cuban spiny lobster exoskeleton Panulirus argus, collected in October 2002 and 2004 from fishery wastes were compared according to their chemical composition and trace elements content. Chemical composition parameters: humidity, ashes, protein, chitin and total lipids contents from samples were determined by gravimetric analysis, while pigment contents was determined by ultraviolet spectrofotometry. Exoskeleton samples were also characterised by x-ray techniques. Elemental analysis was performed by means of a non destructive technique, energy dispersive x-ray fluorescence (EDXRF). It was found that the chemical composition of lobster exoskeleton samples studied were similar to those reported previously for spiny lobster. X-ray fluorescence technique allowed to achieve, for the first time, a comprehensive characterization of trace elements composition for this marine species which it was very similar for samples of two years in study. It was interesting the presence of rhodium and hafnium found in year 2004 sample, while neither Pb, Cd, As, Hg nor other molecules considered as contaminant of this material were detected. It was also found that exoskeleton metal trace contents are lower than maximum biosolids levels accepted in international regulations, therefore agricultural use for this material may be proposed.Original Abstract: Muestras de exoesqueletos de langosta espinosa Panulirus argus provenientes de subproductos pesqueros y colectadas en el mes de octubre de los anos 2002 y 2004 se compararon entre si, en cuanto a su composicion quimica y elementos traza. Los indicadores de la composicion quimica que se determinaron fueron los contenidos de humedad, cenizas, proteinas, quitina y lipidos, todos realizados por metodos gravimetricos, ademas del contenido de pigmentos que se determino por espectrofotometria ultravioleta. Las muestras tambien se caracterizaron por difraccion de Rayos X. Ademas, se les realizo una determinacion elemental por la tecnica no destructiva, de fluorescencia de Rayos X dispersiva de energia (FRXDE) en la que se empleo el procedimiento de parametros fundamentales. Se encontro que la composicion del exoesqueleto es similar a la reportada anteriormente para la langosta espinosa. El empleo de FRXDE permitio obtener por primera vez para esta especie, la caracterizacion exhaustiva del contenido de elementos traza del exoesqueleto, que fue muy similar en los dos anos estudiados. Resulta interesante, la presencia de rodio y hafnio en la muestra de 2004, mientras no se detectaron los elementos Pb, Cd, As, Hg, ni otras sustancias consideradas contaminantes en este material. Se encontro, ademas, que los contenidos de los metales traza en el exoesqueleto estan por debajo de los valores permisibles en normas internacionales para biosolidos, por lo que se propone que este material pudiera ser utilizado para fines agricolas.