Variation Of Mineral Elements And Amino Acids In Swan Mussels Anodonta Woodiana From Different Environment

Anodonta woodiana is a widely distributed freshwater mussel in China. The mussel is a traditional food with good nutritional value and is sometimes used as a food additive. Recent research of the mussel concentrates on its roles for environmental pollution monitoring and the extraction of medical active substances. Previous researches suggested that many mineral elements and amino acids could be detected in A. woodiana. However, no data are available on if the content and composition of mineral elements and amino acids can be influenced by different habitats and different life cycle stages of this mussel. In the present study the soft tissues of adult and juvenile mussels from aquaculture base (farmed mussel) and Wulihu Bay of the Taihu Lake (wild mussel) were investigated the spatial and temporal characteristics of mineral elements and amino acids in order to find the better way to getting the maximum resource usage.1. A characteristic analysis of6mineral element and amino acid contents was comparatively taken by total soft tissues of wild and farmed swan mussels A. woodiana, respectively. Results showed that although the swan mussels from two different habitats generally presented a similar concentration order for the mineral elements or amino acids, the levels of some mineral elements and amino acids could be obvious different. The levels of mineral element Ca, Na, Mg, Sr, and Se (especially Mg and Sr) in the wild mussels were significantly higher or almost the same in comparison with those in the farmed ones, while that of K was very significantly higher in the latter. Moreover, the wild and farmed mussels showed a same amino acids concentration order for17amino acids except for taurine, which contents were significantly higher in the farmed mussels than in the wild ones. The composition of Essential Amino Acid (EAA) in the farmed mussels and wild swan mussels was37.65%and36.75%, and the ratios of EAA to TAA (total amino acids) were60.38%and58.11%, respectively.2. A characteristic analysis of6mineral elements contents was comparatively taken by total soft tissues of farmd ad transplanted swan mussels A. woodiana at different life cycle stages, respectively. Results showed that despite their different habitats, the wild and farmed mussels at the same life cycle stage generally presented a similar concentration order for the mineral elements, and some mineral elements (e.g. K), presenting a similar accumulation trend. Different habitats were not significant effect the concentration order for the mineral elements. In the same habitat, the concentration of Mg, Ca and Sr in A. woodiana, with increasing research time, showed a significant increase, while those of K and Se could significantly increase at first and then decreased. Besides, wild A. woodiana had a priority in the accumulation of K, while the farmed mussel tended to accumulate more Na, Ca and especially Sr.3. A characteristic analysis of amino acids contents was comparativelystudied with total soft tissues of farmd and wild transplanted swan mussels at different life cycle stages, respectively. Results showed that A. woodiana lived in different habitats presented a highly similar concentration order for the amino acids. Though life cycle stages could influence the concentration of some amino acids, highly order consistent could be kept in most of amino acids. At a similar life cycle stages, the A. woodiana lived in two different habitats presented a similarity in the concentration of EAA, concentration of TAA, and the ratio of EAA/NEAA. In addition, the ratio of EAA/NEAA in all mussels at different life cycle stages was kept at an almost the same level. There might exist a maxium level for the concentration of EAA in A. woodiana. Also, the concentration of Tau (Taurine) could increase along with time extended, and farmed A. woodiana showed a higher concent than that in transplanted samples in at a same life cycle stage.The present study suggested that the effect on contents of elements by live habitats was much more obvious than that by life cycle stages, and however, the latter would be influenced more on the contents of amino acids than the former. These results can possible give some advise on future exploiting the mineral elements and amino acids in A. woodiana.