Marine waste products

Coastlines are sought-after locations for industries that ship their products along international waterways. Industry and delicate marine ecosystems rarely make good combinations because industrial pollutants can damage the coast and its native inhabitants. In some instances, poisonous waste products are dumped directly into the ocean. Oil from normal shipping practices creates hazards for the animals nearby. 

Another large set of environmental problems is related to waste production and ntilization. All Asian countries are touched by these consequences of urbanization, indnstrialization and agricultural development, and there are many specific regional pecnliarities in how this problem is solved regarding the air, soil, fresh and marine waterpollntion, hnman and ecosystem health. 

Whitehouse et al [1985] describe the conditions peculiar to the development of a macrofouling community in power plants. Included are the continuous flow of seawater supplying oxygen and food and reduced salt deposition, the lack of competition from algae in the culverts and a reduction in the presence of predators. The waste products from marine life activity together with decomposition products from dead material, is a potential source of nutrients for microfouling. 

However, marine food is not, and probably never will be, contaminated at a level that represents any danger to consumers. The ocean has always received debris from human activities and has a potential for receiving much more and thereby help to solve the waste disposal problems of humans. But as soon as a waste product is released and diluted in the sea it is almost impossible to retrieve. Therefore, in principal, no waste should be disposed of in the sea without clear documentation that it will never create any damage to the marine environment and its living resources. This means that with present knowledge no radioactive wastes should be allowed to be released into the sea. 

One approach to extracting valuable compounds from shellfish processing waste is through the use of marine microorganisms in a procedure referred to as solid state (substrate) fermentation, or SSF. SSF may prove to be an economically advantageous tool for the production of certain compounds from marine waste. For example, the marine fungus Beauveria bassiana can be used to produce chitinase from chitinous prawn waste. Without the fungus, this conversion step normally accounts for 12% of the... 

Industrial chitin is obtained from marine food production waste, i.e., crustacean shells from shrimp, crab or krill [13,14]. The processing of shrimps for human consumption generates 40-50% of the total mass of marine food production waste, which is considered to be one of the main pollutants in coastal areas, as it is dumped into the sea [15]. A small part of the waste is dried and used as chicken feed [14].The major components (on dry mass basis) of shrimp waste are chitin, minerals, carotenoids and proteins thus, the utilisation of this shell food waste as an alternative source to produce chitin may help solve environmental problems related to waste generation. 

The waste stream that reaches the marine environment represents only a small percentage of the quantity of waste produced aimually. However, it is the continued increase in waste production and its persistence related to its slow degradation which... 

Chitin, the precursor of chitosan, is a nitrogen containing polysaccharide and is second most abundant biopolymer after cellulose. It is widely distributed in the shells of crustaceans such as crabs, shrimps, lobsters, prawns, squilla, etc., as well as in the exoskeleton of marine zoo-plankton, including coral, jellyfish, and squid pens. About 20-40% chitin is present the exoskeleton of these animals. It is also present in smaller quantities in insects such as butter flies ladybugs, and the cell walls of yeast, mushrooms, and other fungi [Fig. 19.4]. However, since the crustacean shells [crabs, shrimps, lobsters, etc.] are waste products of food industry, these are commercially employed for the production of chitin and chitosan [1, 4, 18], It is believed that at least 10 gigaton of chitin is synthesized and degraded and it is also estimated that over 150,000 tons of chitin is available for commercial use annually. 

Terpenes are secondary metabolites synthesized mainly by plants, but also by a limited number of insects, marine micro-organisms and fungi. These corrpounds were first considered as waste products from plant metabolism with no specific biological role, but later, the involvement of some terpenes as intermediates in relevant biosynthetic processes was discovered [1]. Additionally, it has been well demonstrated that many terpenes play important ecological roles [1] as in plant defence, for example as insect repellents, and in symbiotic mechanisms, for example as attractants to specific insect species to stimulate cross pollination. 

Johnson, E.L. and Peniston, Q.P 1982. Utilization of shellfish waste for chitin and chitosan production. In Chemistry Biochemistry of Marine Food products, eds. G.J. Martin, C.E. Hebard, and W.R. Ward, pp. 514—522. Westport, CT AVI Publishing Co. 

There is also pressure from marine biologists and those concerned with river pollution prevention who would like to see such waste products disposed of on agricultural land because they want to keep them away from water-courses and estuaries. Then there are people who still see pollution as simply a short-term problem associated with the generation of localised biological oxidation demand, so the dispersion of these wastes in soil, with its tremendous oxidative capacity, is seen as an adequate solution to the problem of their disposal. However, we have to consider the levels of metals and other elements present in the materials we deliberately add to the soil and the probable consequences of such additions. 

The most interesting feature of this light sensitivity is that compensatory movements are effected in terms of minutes or hours. The deleterious effect of failure to compensate would not, however, be evident for a considerably longer period. That is to say, the lethal effect of excessive insolation of the phycobiont is measurable in days rather than in hours, particularly in the marine environment of many of these organisms. It is therefore necessary to postulate a further factor in these symbiotic systems. This is most likely to be a waste-product feedback reaction which triggers a locomotory response. 

Combined-cycle systems are used in both land and marine applications employing diesel engines or gas turbines (which usually provide the first power source) and by large process industries that produce significant heat-containing, by-product waste streams. 

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