Shellfish, characteristics

Characteristics of the receiving ecosystem (e.g. solid type, ground water, drinking water, fish/shellfish water, bathing water) and how it migrates from one environment to another. 

Coupled with successful primary prevention are ongoing monitoring programs for the organisms and their toxins, both in the environment and in the seafood. The molluscan shellfish (i.e., oysters, clams, mussels, and scallops) are the species associated with shellfish poisonings. The absence of characteristics such as abnormal taste, smell, or appearance precludes sensory inspection for these toxins. Instead, ensuring seafood safety relies on testing seawater and the seafood itself The assays used to detect toxins in seafood have evolved as analytic methods and instrumentation have improved. The American Public... 

Since the late 1960 s problems related to ccxitaminaticxi of fish and shellfish have been recognized. The problem compounds share one characteristic biopersistence. Compounds such as various salts of lead or mercury have contaminated shellfish or fish living in either fresh or salt water. Chlorinated compounds such as DDT, PCB and dioxins have been found in fish living in fresh water rivers and lakes and to some extent in the Baltic and Mediterranean Seas (25). 

The main genera responsible for freshwater toxic blooms are Microcystis, Anabaena, Aphanizomenon and Oscillatoria. Toxins produced include 1. anatoxins, alkaloids and peptides of Anabaena 2. the peptide microcystin and related peptides of Microcystis 3. aphantoxins, compounds of Aphanizomenon with properties similar to some paralytic shellfish poisons. Properties of Oscillatoria toxin suggest they are peptides similar to those of Microcystis. Microcystis toxins are peptides (M.W. approx. 1200) which contain three invariant D-amino acids, alanine, erythro-3-methyl aspartic and glutamic acids, two variant L-amino acids, N-methyl dehydro alanine and a 3-amino acid. Individual toxic strains have one or more multiples of this peptide toxin. The one anatoxin characterized is a bicylic secondary amine called anatoxin-a (M.W. 165). The aphantoxin isolated in our laboratory contains two main toxic fractions. On TLC and HPLC the fractions have the same characteristics as saxitoxin and neosaxitoxin. 

Castillo, R., Carrilo, T., Blanco, C., Quiralte, J., and Cuevas, M. (1994). Shellfish hypersensitivity Clinical and immunological characteristics. Allergol. Immunopathol. 22, 83-87. 

Wu, A. Y., and Williams, G. A. (2004). Clinical characteristics and pattern of skin test reactivities in shellfish allergy patients in Hong Kong. Allergy Asthma Proc. 25, 237-242. Yamura, T., and Kurose, H. (1966). Oyster-shucker s dermatitis. Arerugi 15, 813. 

Bioactive peptides as products of hydrolysis of diverse marine invertebrate (shellfish, crustacean, rotifer, etc.) proteins are the focus of current research. After much research on these muscles and byproducts, some biologically active peptides were identified and applied to useful compounds for human utilization. This chapter reviews bioactive peptides from marine invertebrates in regarding to their bioactivities. Additionally, specific characteristics of antihypertensive, anti-Alzheimer, antioxidant, antimicrobial peptide enzymatic production, methods to evaluate bioactivity capacity, bioavailability, and safety concerns of peptides are reviewed. 

Edward, N. J., Arroll, T. A., and Fan, Z. (1996). Specificity and some physicochemical characteristics of the antibacterial activity from blue crab Callinectus sapidus. Fish Shellfish Immunol. 6, 403-413. 

Superabsorbent polymers are used as a liquid-absorber in food packaging systems. In these systems, the superabsorbent polymers absorb juice or water from fresh foods such as raw chicken, shellfish, and other meats or from frozen foods as they thaw. Chilled superabsorbent polymer gels may also be used as a dry-cooling medium. The water-swollen gel, contained in a durable plastic bag, is frozen and used to keep perishable foods cold. In addition to its liquid-water-absorption characteristic, superabsorbent polymers absorb water from the vapor state and therefore may be used to control humidity. 

Zettler, M. L., Bonsch, R., Gosselck, E, 2001. Distribution, abundance and some population characteristics of the ocean quahog, Arctica islandica (Linnaeus, 1767), in the Mecklenburg Bight (Baltic Sea). Journal of Shellfish Research, 20, 161-169. 

Although the ELISA has good accuracy and precision characteristics for YTXs, its use in shellfish monitoring programs will be limited to screening until the relationship of the enhanced responses to the regulated levels of YTXs is securely established for different shellfish species. 

Seasonal and longer-term temporal variations in neurotoxin poisonings have been reported in some instances but not in others. Temporal variations in human illness are the combined product of variations in dinoflagellate blooms, the proportion of dinoflagellate blooms that produce toxin, fish and shellfish depuration patterns, dietary preferences, fish and shellfish availability, public health measures, and surveillance system characteristics. Essentially, in all instances, the relative contribution of these various factors to the presence or absence of temporal variation is unknown. 

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