通过室内急性暴露实验研究了翡翠贻贝（Perna viridis）消化腺富集Cu及其MTLP（metallothionein like protein）水平随时间的变化规律．结果表明，2种Cu浓度暴露条件下（12．7μg／L和63．5μg／L），贻贝消化腺内Cu的平均吸收速率分别...通过室内急性暴露实验研究了翡翠贻贝（Perna viridis）消化腺富集Cu及其MTLP（metallothionein like protein）水平随时间的变化规律．结果表明，2种Cu浓度暴露条件下（12．7μg／L和63．5μg／L），贻贝消化腺内Cu的平均吸收速率分别为2．045和7．028μg·（g·d）^-1，富集系数分别为2074和1619．实验测定了所有样本的溶解态Cu与总Cu含量，2个暴露组二者的比值随时间呈现出不同的变化趋势，低浓度组先降低随后上升到与对照样本几乎相同的水平，而高浓度组一直呈下降趋势，表明不同污染程度生物体内金属消化机制进程存在差异．利用Brdicka极谱法测定了贻贝消化腺内MTLP的含量，对照组贻贝消化腺的MTLP平均含量为（0．551±0．037）ms／g；12．7μg／L Cu暴露组MTLP含量随时间的变化范围是0．407～0．699ms／g，而63．5μg／L Cu暴露组在暴露初始MTLP水平就显著增加（P〈0．001），变化范围由初始0．942mg／g降至0．826mg／g．分析结果表明贻贝消化腺内的MTLP水平随着水体及生物体内的金属含量升高而增加，并与体内Cu浓度成明显的负指数增长关系（P〈0．0001）．展开更多
Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show tha...Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels＇ uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.展开更多
Green-lipped mussels (Perna viridis) were collected from a local mariculture site and placed in pre-cleaned sea water tanks containing 0, 0.2, 0.5 and 1.3 μg/ml CdCl2. The level of Cd in the gill, viscera and gonad w...Green-lipped mussels (Perna viridis) were collected from a local mariculture site and placed in pre-cleaned sea water tanks containing 0, 0.2, 0.5 and 1.3 μg/ml CdCl2. The level of Cd in the gill, viscera and gonad was measured. The concentration of Cd in the 3 tissues increased linearly over 4 days' of exposure. The rate of uptake depends on the concentration of Cd in the water. In the 3 tissues studied, the maximum rate of uptake (Vmax) was highest in the gill (500μg/g dry weight/day), followed by viscera (100μg/g dry weight/day) and gonad (56.8 μg/g dry weight/day). The majority of the Cd taken up was bound to a fraction of the heat-stable proteins similar to metallothioneins. The rate of Cd depuration from the tissues was poor. There was no change in Cd concentration over 8 days' depuration in clean water展开更多
The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites (10 from the west and 2 from the east coastal wate...The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites (10 from the west and 2 from the east coastal waters) of Peninsular Malaysia. All samples showed that the levels of Cd, Pb and Zn were generally higher in the gill than those in the remaining soft tissues. These results could be due to the fact that gills are the first organ of metal accumulation and larger surface area with mucus sheets in the organ. Since the mussel gill is a better accumulator of Cd, Pb and Zn of ambient seawater than remaining soft tissue, it is a potential indicator of ambient levels of dissolved metals in the ambient seawater. However, further validations based on laboratory conditions are needed.展开更多
This research was carried out to study the heavy metals removal like arsenic (As), lead (Pb), cadmium (Cd), nickel (Ni) and mercury (Hg) from Perna viridis. The trisodium citrate with Ru/Mn (25:75)-Al2O3 catalyst were...This research was carried out to study the heavy metals removal like arsenic (As), lead (Pb), cadmium (Cd), nickel (Ni) and mercury (Hg) from Perna viridis. The trisodium citrate with Ru/Mn (25:75)-Al2O3 catalyst were used for the treatment medium with optimum treatment conditions at 500 μg/g of dosage, at temperature of 35°C ± 1°C, at pH 7, for 5 hours of duration and in the presence of compressed air (flow rate 895.50 mL/min). The introduction of Ru/Mn (25:75)-Al2O3 catalyst at 100°C calcination temperature on the trisodium citrate medium indicates the reduction of heavy metals which achieved the permissible limit by Malaysian Food Regulations (1985) and Commission Regulation of EU (2006). The original concentrations of As: 1.65 ± 0.89 μg/g, Hg: 12.42 ± 0.53 μg/g, Pb: 6.25 ± 0.69 μg/g, Cd: 1.27 ± 0.25 μg/g and Ni: 2.00 ± 1.05 μg/g were reduced to As: 0.75 ± 0.04 μg/g (54.34%), Hg: 0.4 ± 0.02 μg/g (96.79%), Pb: 1.07 ± 0.02 μg/g (82.89%), Cd: 0.32 ± 0.10 μg/g (75.02%) and Ni: 0.76 ± 0.01 μg/g (61.83%). ICP-MS and MHS-AAS techniques were used for the metals analysis and the catalyst was characterized through X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray (EDX) and Nitrogen Absorption (NA).展开更多
Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at...Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase （ρ0） and mean residence time （τ） were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww （wet weight）. The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels.展开更多
Invasive species are often characterised by the introduction of low numbers of individuals and a small genetic pool which could give rise to a population with a lower genetic diversity than the original population. Pe...Invasive species are often characterised by the introduction of low numbers of individuals and a small genetic pool which could give rise to a population with a lower genetic diversity than the original population. Perna viridis was first reported on the west coast of Trinidadin1990 inthe Point Lisas Industrial estate. They may have been first introduced either as juvenile free floating mussels (spat) or as adults attached to the hulls of ships. This gregarious species spread rapidly throughout the Caribbean toVenezuela,KingstonHarbor(Jamaica) and by 1999 was reported inTampaBay(Florida). Genetic analysis was done on tissue samples fromTrinidadto determine the genetic similarity of newly collected specimens (2009) with archived specimens (collected 1994). Results suggest that there may not be any genetic variation in the population of Perna viridis, even approximately 20 years after initial colonization. These results suggest that there was no evidence of genetic bottlenecks in the population of P. viridis fromTrinidad.展开更多
文摘Experiments were designed to expose the filter-feeding bivalve Perna viridis to different Cd-contaminated water environments in order to compare the different pathways through which Cd is accumulated. Results show that mussels can accumulate Cd through seawater, food, sediment and suspended particle pathways in a short period of time. Mussels＇ uptake of Cd through the seawater pathway reaches the highest concentration approximately 3 and 9 times larger than through the algae and sediment pathways respectively after 7 d. This indicates that the Cd-accumulation through seawater is most efficient. Results also indicate that the uptake directly through contaminated algae, particles or sediments ingested by mussels is less important when compared with the uptake of Cd by mussels through the seawater pathway. Metal uptake pathways and mechanisms of bioaccumulation by marine bivalve are also discussed in this paper.
文摘Green-lipped mussels (Perna viridis) were collected from a local mariculture site and placed in pre-cleaned sea water tanks containing 0, 0.2, 0.5 and 1.3 μg/ml CdCl2. The level of Cd in the gill, viscera and gonad was measured. The concentration of Cd in the 3 tissues increased linearly over 4 days' of exposure. The rate of uptake depends on the concentration of Cd in the water. In the 3 tissues studied, the maximum rate of uptake (Vmax) was highest in the gill (500μg/g dry weight/day), followed by viscera (100μg/g dry weight/day) and gonad (56.8 μg/g dry weight/day). The majority of the Cd taken up was bound to a fraction of the heat-stable proteins similar to metallothioneins. The rate of Cd depuration from the tissues was poor. There was no change in Cd concentration over 8 days' depuration in clean water
文摘The distribution and concentrations of Cd, Cu, Pb and Zn were determined in the gills and remaining soft tissues of Perna viridis collected from 12 geographical sites (10 from the west and 2 from the east coastal waters) of Peninsular Malaysia. All samples showed that the levels of Cd, Pb and Zn were generally higher in the gill than those in the remaining soft tissues. These results could be due to the fact that gills are the first organ of metal accumulation and larger surface area with mucus sheets in the organ. Since the mussel gill is a better accumulator of Cd, Pb and Zn of ambient seawater than remaining soft tissue, it is a potential indicator of ambient levels of dissolved metals in the ambient seawater. However, further validations based on laboratory conditions are needed.
文摘This research was carried out to study the heavy metals removal like arsenic (As), lead (Pb), cadmium (Cd), nickel (Ni) and mercury (Hg) from Perna viridis. The trisodium citrate with Ru/Mn (25:75)-Al2O3 catalyst were used for the treatment medium with optimum treatment conditions at 500 μg/g of dosage, at temperature of 35°C ± 1°C, at pH 7, for 5 hours of duration and in the presence of compressed air (flow rate 895.50 mL/min). The introduction of Ru/Mn (25:75)-Al2O3 catalyst at 100°C calcination temperature on the trisodium citrate medium indicates the reduction of heavy metals which achieved the permissible limit by Malaysian Food Regulations (1985) and Commission Regulation of EU (2006). The original concentrations of As: 1.65 ± 0.89 μg/g, Hg: 12.42 ± 0.53 μg/g, Pb: 6.25 ± 0.69 μg/g, Cd: 1.27 ± 0.25 μg/g and Ni: 2.00 ± 1.05 μg/g were reduced to As: 0.75 ± 0.04 μg/g (54.34%), Hg: 0.4 ± 0.02 μg/g (96.79%), Pb: 1.07 ± 0.02 μg/g (82.89%), Cd: 0.32 ± 0.10 μg/g (75.02%) and Ni: 0.76 ± 0.01 μg/g (61.83%). ICP-MS and MHS-AAS techniques were used for the metals analysis and the catalyst was characterized through X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-Ray (EDX) and Nitrogen Absorption (NA).
基金supported by the National Natural Science Foundation of China (No. 40876039)the Science and Technology Program of China (No. 2008FY110100)the Foundation of Scientific and Technological Planning Project of Guangdong Province (No. 2006B36601005)
文摘Time-dependent Zn and Cd accumulation and metallothionein like protein （MTLP） induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase （ρ0） and mean residence time （τ） were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww （wet weight）. The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels.
文摘Invasive species are often characterised by the introduction of low numbers of individuals and a small genetic pool which could give rise to a population with a lower genetic diversity than the original population. Perna viridis was first reported on the west coast of Trinidadin1990 inthe Point Lisas Industrial estate. They may have been first introduced either as juvenile free floating mussels (spat) or as adults attached to the hulls of ships. This gregarious species spread rapidly throughout the Caribbean toVenezuela,KingstonHarbor(Jamaica) and by 1999 was reported inTampaBay(Florida). Genetic analysis was done on tissue samples fromTrinidadto determine the genetic similarity of newly collected specimens (2009) with archived specimens (collected 1994). Results suggest that there may not be any genetic variation in the population of Perna viridis, even approximately 20 years after initial colonization. These results suggest that there was no evidence of genetic bottlenecks in the population of P. viridis fromTrinidad.
