Assessment of carotenoid production by Dunaliella salina in different culture systems and operation regimes

The effect of operation regime and culture system on carotenoid productivity by the halotolerant alga Dunaliella salina has been analyzed. Operation strategies tested included batch and semi continuous regime, as well as a two-stage approach run simultaneously in both, open tanks and closed reactor. The best results were obtained with the closed tubular photobioreactor. The highest carotenoid production (328.8 mg carotenoid l−1 culture per month) was achieved with this culture system operated following the two-stage strategy. Also, closed tubular photobioreactor provided the highest carotenoid contents (10% of dry weight) in Dunaliella biomass and β-carotene abundance (90% of total carotenoids) as well as the highest 9-cis to all-trans β-carotene isomer ratio (1.5 at sunrise).Comisión Interministerial de Ciencia y Tecnología IFD 1997-1780IFAPA CO3-125Plan Andaluz de Investigación CVI13

Potential of the Senegal sole Solea senegalensis Kaup, 1858 for marine aquaculture diversification

The potential of Senegal sole Solea senegalensis Kaup, 1858 for marine aquaculture diversification is analysed. An initial historic review attempts to explain the current situation of this sole species's aquaculture. Recent advances are then assessed, highlighting progress in captive reproduction techniques, even though a great deal of scientific knowledge is still lacking. Ongrowing of sole has been successfully conducted in several instances, but progress is limited by the excessive occurrence of opportunistic diseases. These may be, at present, a consequence of suboptimal husbandry conditions which make sole unable to achieve a sufficiently adequate physiological status to generate proper resistance.Se analizan las posibilidades que el lenguado senegalés Solea senegalensis Kaup, 1858 presenta para diversificar la acuicultura marina. Se trata de una revisión en la que se describe la evolución del cultivo de esta especie como paso previo para comprender su situación actual. A continuación, se valoran los avances más recientes, observándose cómo la zootecnia de la reproducción en cautividad va progresando en respuesta al esfuerzo investigador invertido, aunque todavía son numerosas las carencias de su conocimiento científico de base. El engorde de lenguados ha producido en varios casos resultados satisfactorios, sin embargo, su avance se ve limitado por una excesiva incidencia de patologías oportunistas, la mayoría de las cuales son consecuencia de condiciones de procedimiento que no favorecen el bienestar fisiológico suficiente para hacerles frente.Instituto Español de Oceanografí

Testing equipment for the improvement of mechanical devices to minimize damage to fruit in commercial packing lines.

Damages -reduced in fruit packing lines is a major cause of grace reduction and quality loos in fresh marks: fruit. Fruit must be treated gently during in sir handling to improve their qualityin order to get a good price in a competitive market. The correct post-hardvest handling in fruit packing lines is a prerequisite to cut down the heavy post-harvest losses. Fruit packing lines must be evaluated, studying their design, the impacts applied to the fruits, the characteristics of the materials, etc. This study establishes the possibility of carrying out modifications and tests in a packing line during a long period of time. For this purpose, an experimental fruit packing line has been designed and located in the Agricultural Engineering Department of the Polythecnic University of Madrid with the aim of improving mechanical devices and fruit handling conditions to minimize damage to fruit. The experimental line consists of several transporting belts, one rollers transporter, one sizer, one elevator, one singularizer, and three trays to receive the calibrated fruit. The line has a length of 6.15 m and a width cf 1.9 m. Movement of the different components is regulated by electric motors with variable velocity electronically controlled. The height of the transfer points is variable and can be easily modified. The experimental line has been calibrated using two instrumented spheres IS 100 (8.8 cm Ø and6.2cm Ø). Average acceleration values obtained in all the transfers of the experimental line lay under 80 g's, although there is big variation for some of them being some values above 100 g's