COMPARISON IN ACCUMULATION,METABOLISM AND PHYSIOLOGICAL STRESS OF PARALYTIC SHELLFISH TOXINS IN TWO SPECIES OF MUSSELS
Mussels exhibit a robust capacity for environmental adaptation and are often utilized as indicators to environmental pollution.It is known that mussels accumulate toxins during harmful algal blooms at a significantly higher rate than other bivalve mollusks do.Two mussel species,M.unguiculatus and M.galloprovincialis,were chosen for our exposure experiments in this regard.Mussels were fed with toxin-producing algae(Alexandrium catenella)based on their soft tissue weight ratio.After 7 days of accumulation,M.galloprovincialis showed the highest content of PSTs at 889.1 μg STXeq/kg,surpassing the limit of 800 μg STXeq/kg.In contrast,the PSTs content in M.unguiculatus was relatively lower at 358.6 μg STXeq/kg.The rate of PSTs elimination in M.galloprovincialis(88.8％)was significantly higher than that in M.unguiculatus(42.5％).The rates of daily PSTs accumulation in M.galloprovincialis and M.unguiculatus exhibited a significant positive correlation with the absorption efficiency(P＜0.05),whereas no significant correlation with the clearance rate(P＞0.05)was observed.The clearance rate and absorption efficiency of M.galloprovincialis to toxin-producing algae were twice as high as those of M.unguiculatus.Additionally,the hepatopancreas of M.galloprovincialis exhibited more severe oxidative stress and pathological damage,resulting in reduced tissue transfer of PSTs and a lower elimination rate compared to M.unguiculatus.The proportion of PSTs in the edible tissue of M.galloprovincialis was found higher than those in M.unguiculatus.M.unguiculatus could reduce toxin accumulation through decreased feeding behavior,whereas M.galloprovincialis showed a notable oxidative stress response in the presence of high PSTs contents.Therefore,distinctions in physiological stress ultimately resulted in the variations in the accumulation of PSTs between the two mussel species.
musselsinterspecific variationaccumulation and metabolismfeeding behaviorphysiological stress
万方数据
维普
