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International audience; To sustain eel aquaculture, development of reproduction in captivity is vital. The aim of this review is to assess our current knowledge on the nutrition of broodstock eels in order to improve the quality of broodstock under farming conditions, drawing information from wild adult eels and other marine pelagic spawners. Freshwater eels spawn marine pelagic eggs with an oil droplet (type II), and with a large perivitelline space. Compared with other marine fish eggs, eel eggs are at the extreme end of the spectrum in terms of egg composition, even within this type II group. Eel eggs contain a large amount of total lipids, and a shortage of neutral lipids has been implied a cause for reduced survival of larvae. Eel eggs have higher ARA but lower EPA and DHA levels than in other fish. Too high levels of ARA negatively affected reproduction in the Japanese eel, although high levels of 18:2n-6 in the eggs of farmed eels were not detrimental. The total free amino acid amount and profile of eel eggs appears much different from other marine pelagic spawners. Nutritional intervention to influence egg composition seems feasible, but responsiveness of farmed eels to induced maturation might also require environmental manipulation. The challenge remains to succeed in raising European eel broodstock with formulated feeds and to enable the procurement of viable eggs and larvae, once adequate protocols for induced maturation have been developed

The quality of commercial cocoa beans, the principal raw material for chocolate production, relies on the combination of factors that include the type of planting material, the agricultural practices, and the post-harvest processing. Among these, the fermentation of the cocoa beans is still the most relevant since it is the process whereby the precursors of the cocoa flavor arise. The formation of these precursors depends on the activity of different microbial groups on the beans pulp. A comparison of fermentations in different countries showed that a well-defined microbial succession does not always take place and that the role of Bacillus spp. in this process remains unclear. Considering the overriding importance of the fermentation to achieve high quality commercial cocoa beans, we discuss the need of addressing the impact of the farming system, the ripeness state of the pods, and the role of microbial interactions on the fermentation in future research. In addition, the problem of high acidification cocoa beans, aspects dealing with the volatile fraction of the flavor, and the cocoa butter properties, all were identified as critical aspects that need further investigation. The standardization of the microbiological methods and the application of metagenomic approaches would magnify the knowledge in this domain.

3-N-oxalyl-L-2,3-diaminopropanoic acid (beta-ODAP) is a neuroexcitatory non- protein amino acid identified in grass pea (Lathyrus sativus L.) and in ginseng (Panax spp). Its presence in the drought tolerant grass pea is thought to be responsible for the crippling disease neurolathyrism, while in the longevity promoting ginseng it is named dencichine and praised for its haemostatic properties. Some properties of beta-ODAP are put in perspective.

A number of scientific studies have investigated aspects of soles ( Solea solea and S. senegalensis) ecology, population genetics and biology in their natural environment, and the species have been extensively studied in captivity during the last decade. Studies on the genetic population structure of sole indicate that several distinct breeding populations exist within its distributional range in European waters. Recent studies suggest a phylogenetic relatedness of S. solea and S. senegalensis, being found as closest sister lineages in most reconstructions. However, studies on molecular genetics and morphological traits give diagnostic differences that consistently lead to their taxonomic separation at the specific rank. Studies show that sole spawn readily in captivity, and the buoyant, fertilized eggs are easily collected. Stocking density during maturation should be 1-1.5 kg/m(2), and temperature should be kept above 16degreesC ( S. senegalensis) or between 8 and 12degreesC ( S. solea). In nature, the onset of spawning is related to a rise in temperature occurring during spring ( March-June). Salinity should be kept constant around 33-35& and the fish reared under simulated natural photoperiod ( LDN). In other cultured flatfish species, a change in the photoperiod is the key environmental signal used to manipulate and control maturation, but at present time there are no published work that verifies or contradicts this for either S. senegalensis or S. solea. Studies indicate that a mixture of inert and live food may increase the weaning success of sole fry, and this can be further enhanced by using attractants in the dry feed. Future experiments are needed to determine the ideal time to commence weaning and determine the minimum duration of this period. Studies on alternative feeding strategies are also required. The effect of temperature and photoperiod on juvenile growth has not been studied systematically in neither of the two species and the relative importance of a direct photoperiod effect on growth in sole therefore remains to be defined.

In sheltered, eutrophicated estuaries, reduced nitrogen (NH x ), and pH levels in the water layer can be greatly enhanced. In laboratory experiments, we studied the interactive effects of NH x , pH, and shoot density on the physiology and survival of eelgrass (Zostera marina). We tested long-term tolerance to NH x at pH 8 in a 5-week experiment. Short-term tolerance was tested for two shoot densities at both pH 8 and 9 in a 5-day experiment. At pH 8, eelgrass accumulated nitrogen as free amino acids when exposed to high loads of NH x , but showed no signs of necrosis. Low shoot density treatments became necrotic within days when exposed to NH x at pH 9. Increased NH3 intrusion and carbon limitation seemed to be the cause of this, as intracellular NH x could no longer be assimilated. Remarkably, experiments with high shoot densities at pH 9 showed hardly any necrosis, as the plants seemed to be able to alleviate the toxic effects of high NH x loads through joint NH x uptake. Our results suggest that NH x toxicity can be important in worldwide observed seagrass mass mortalities. We argue that the mitigating effect of high seagrass biomass on NH x toxicity is a positive feedback mechanism, potentially leading to alternative stable states in field conditions.