栉孔扇贝体内麻痹性贝毒的累积与排出过程研究

通过室内摄食实验,研究了栉孔扇贝(Chlamys farreri)对麻痹性贝毒(PSP)产毒藻的敏感性及其累积和排出毒素的特征.有毒微小亚历山大藻(Alexandrium minutum)在短时间内可对栉孔扇贝的摄食有一定的抑制作用,且投喂毒藻的浓度越大,对摄食作用的抑制越明显.栉孔扇贝对PSP贝毒的累积能力很强,实验中,48 h后内脏累积毒素就高达5000μg STXeq100g-1,但其毒素排出速率较慢,在24d解毒阶段后内脏中的毒素还没有下降至国际贝毒食用安全标准水平的80μg STXeq 100g-1.各毒素组成比在整个累积与排除过程中有较大变化,GTX1,GTX4在累积阶段比例下降,同时GTX2,GTX3比例上升;内脏中GTX2:GTX3的比值逐渐增加.毒藻中PSP贝毒毒素组成和贝体中PSP贝毒毒素组成之间的主要差别是GTX4含量的减少和GTX1含量的升高;而扇贝粪便中的毒素组成却与对数生长期的毒藻极为接近.

Accumulation and depuration of Paralytic Shellfish Poisons(PSP) in Chinese Scallop Chlamys farreri

In this paper, theaccumulation, and deputation of Paralytic Shellfish Poisons(PSP) in Chinese scallop Chlamys farreri was studied.Through short-terrrt feeding experiment, it was found out that toxic algae could reduce the clearance rate of scallops, but they could adapt to such condition and maintain a constant clearance rate and experienced no mortality or sublethal effect during intoxification.The scallops used in the experiment, Chlamys farreri,has a high ability to accumulate PSP.It reached 5 000 μg STXeq 100 g-1 in viscera after 48h exposed to toxic Alezandrium minutum，and the rate of detoxification is slow.Toxin content found in viscera is much higher than in other tissues, accounting 97% of the total.The ratio of different PSP toxiwhas changed during the whole experimental period, for example, the ratio of GTXl and GTX4 to total toxins decreased while that of GTX2 and GTX3 increased.The decrease of GTX2 is slower than that of GTX3 in viscera over the deputation period.Further more, the toxin profile in shellfish is different to that in algae.Toxin profile in shellfish feces matches well with that in early stage of Alezandrium mznutum in batch culture.