Marine organism

Carbonate rocks are not normally transported over long distances, and we find carbonate reservoir rocks mostly at the location of origin, in situ . They are usually the product of marine organisms. However, carbonates are often severely affected by diagenetic processes. A more detailed description of altered carbonates and their reservoir properties is given below in the description of diagenesis . 

Phosphatic limestone is usually a high calcium type that contains appreciable percentages (up to 5%) phosphoms. It originates from invertebrate marine organisms. 

Fig. 7. Toxicity of chlorine to aquatic organisms, (a) Time-dependent mortaUty (50%) of four example species in various levels of total residual chlorine in the laboratory, where for A, A.losa aestivalis and B, Salmogairdnerii r (correlation coefficient of the curve) = —0.96 and for C, P/euroneetesplatessa and D, Salmo trutta r = —0.98. (b) A summary of chlorine toxicity to freshwater species, indicating overall no-effect thresholds for acute and chronic exposures. Numbers indicate where more than one test yielded the same result. A different summary figure appHes to marine organisms because of differences in the...

Rich sources of vitamin A include dairy products such as milk cheese, butter, and ice cream. Eggs as well as internal organs such as the Hver, kidney, and heart also represent good sources. In addition, fish such as herring, sardines, and tuna, and in particular the Hver oil from certain marine organisms, are excellent sources. Because the vitamin A in these food products is derived from dietary carotenoids, vitamin A content can vary considerably. Variation of vitamin A content in food can also result from food processing and in particular, oxidation processes (8). 

C. Ireland, D. Roll, T. Molinski, T. MeKee, M. Zabriske and J. Swersey, in Biomedical Importance of Marine Organisms, ed. D. G. Fautin, California Aeadeiny of Seienees, San Franeiseo, 1988, p. 41. C. Ireland, B. Copp, M. Foster, L. MeDonald, D. Radisky and C. Swersey, in Marine Biotechnology, vol. 1, Pharmaceutical and Bioactive Natural Products, ed. D. Attaway and O. Zaborsky, Plenum Press, New York, 1993, eh. 1, p. 1. 

The underlying assumption driving marine natural products chemistry research is that secondary metabolites produced by marine plants, animals, and microorganisms will be substantially different from those found in traditional terrestrial sources simply because marine life forms are very different from terrestrial life forms and the habitats which they occupy present very different physiological and ecological challenges. The expectation is that marine organisms will utilize completely unique biosynthetic pathways or exploit unique variations on well established pathways. The marine natural products chemistry research conducted to date has provided many examples that support these expectations. 

The volatile hydrocarbons, albeit comparatively toxic to marine organisms, evaporate relatively quickly and hence serve little purpose as diagnostic aids. The... 

Fatty acids with odd numbers of carbon atoms are rare in mammals, but fairly common in plants and marine organisms. Humans and animals whose diets include these food sources metabolize odd-carbon fatty acids via the /3-oxida-tion pathway. The final product of /3-oxidation in this case is the 3-carbon pro-pionyl-CoA instead of acetyl-CoA. Three specialized enzymes then carry out the reactions that convert propionyl-CoA to succinyl-CoA, a TCA cycle intermediate. (Because propionyl-CoA is a degradation product of methionine, valine, and isoleucine, this sequence of reactions is also important in amino acid catabolism, as we shall see in Chapter 26.) The pathway involves an initial carboxylation at the a-carbon of propionyl-CoA to produce D-methylmalonyl-CoA (Figure 24.19). The reaction is catalyzed by a biotin-dependent enzyme, propionyl-CoA carboxylase. The mechanism involves ATP-driven carboxylation of biotin at Nj, followed by nucleophilic attack by the a-carbanion of propi-onyl-CoA in a stereo-specific manner. 

Alkali metal nitrates can be prepared by direct reaction of aqueous nitric acid on the appropriate hydroxide or carbonate. LiN03 is used for scarlet flares and pyrotechnic displays. Large deposits of NaN03 (saltpetre) are found in Chile and were probably formed by bacterial decay of small marine organisms the NH3 initially produced... 

Carboline and isoquinoline alkaloids from marine organisms 96MI5. 

New bioactive O- and N-heterocycles from Chinese marine organisms 99PAC1147. 

D. Hainzl, J. Burhenne and H. Pariar, HRGC-ECD and HRGC-NICI SIM quantification of toxaphene residues in selected marine organism by envir onmentally relevant chloroboT nanes as standard , Chemosphere 2S 237-243 (1994). 

Much attention has been given in recent years to the environmental aspects of both the drilling operation and the drilling fluid components. Well-deserved concern with the possibility of polluting underground water supplies and of damaging marine organisms, as well as with the more readily observed effects on soil productivity and surface water quality, has stimulated widespread studies on this subject. 

The vast majority of bioassays on marine organisms have been conducted on toxicants that are soluble in seawater. Because drilling mud contains solid particles, a special procedure had to be developed. 

The mysid shrimp, Mysidopsis bahia, is the test organism for the liquid and suspended particulate phases. This species has been shown to be exceptionally sensitive to toxic substances and is considered to be a representative marine organism for bioassay testing by EPA. An LCj, is determined the suspended particulate phase (SPP) bioassay tests. 

Southwell, C. R., Bultman, J. D. and Huimner, J. R., Influence of Marine Organisms on the Life of Structural Steels, US Naval Research Laboratory Report No. 7672, Washington DC, USA (1974)... 

Resistance to marine organisms. In the case of submarine lines, the coating should not be easily penetrated by marine life, e.g. mussels, borers, barnacles, etc. 

In tests in sea-water where accumulations of marine organisms are likely, specimens exposed parallel to each other should be spaced far enough apart to ensure that the space between specimens will not become completely... 

Much remains to be learned—only a few hundred of the more than 500,000 > known species of marine organisms have been examined—but it is clear that organohalogen compounds are an integral part of the world around us. 

In Mollusca, bioluminescence occurs in a great variety of organisms having distinctly different appearances, such as the classes Gastropoda (limpets, snails and sea hares), Bivalvia (clams), and Cephalopoda (squids and octopuses). All luminous molluscs currently known are marine organisms, except the New Zealand fresh water limpet Latia neritoides and the Malaysian land snail Quantula (Dyakia) striata. No information is yet available on the biochemical aspects of the Quantula luminescence. 

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