Shrimp extract from prawn waste

A method has been described for the preparation of protein extract from prawn waste. The process consists of extracting the protein from minced fresh prawn head and shell waste by treatment with mild alkali and neutralisation and concentration of the filtrate into a semisolid consistency. The yield of the final product is about 20% of the weight of fresh prawn waste.

Utilization of the fish waste self-brine of fish curing industry as farm fertilizer

Large quantities of self-brine accumulating in curing tanks during the process of commercial fish salting is mostly wasted at present. This liquor exuded from the fish during the process of salting contains considerable amounts of soluble proteins and minerals. Due to the presence of organic matter the self-brine quickly putrefies causing nauseating smell. This renders the whole surroundings insanitary and often leads to health hazards to neighboring localities. Any economic method of utilising this waste brine and converting it into some useful product will be a tangible help to the fish curing industry. Hence, a method is given for converting this waste self-brine into a cheap and efficient fertilizer.

Preparation of lime from mussel shelf waste

A process is described for the utilisation of mussel shell wastes by their conversion into lime, which may be used for white washing and plastering.

Use of fermented kitchen waste in rearing Penaeus monodon larvae

Fermented vegetable and kitchen wastes are available as feeds for not only zoea but also mysis and up to certain points in the postlarval stages of sugpo, Penaeus monodon. It is recommended that the hatchery use fermented wastes as larval feed for P.monodon when diatoms or brine shrimp nauplii are lacking or in short supply. Among three stages namely, zoea, mysis and postlarva, the survival rate during postlarva particularly after P SUB-4 was quite low. The problems encountered are as follows: (a) how to prevent fermented particles from lumping, (b) how to prevent them from easily sinking to the bottom, and, (c) how to prevent bacteria and fungi, particularly Lagenidium sp blooming.

Utilisation of squid waste as meal

The squid waste which includes head, tentacles, viscera, fin, skin and pen amounts to 52% of the whole weight and is discarded at present. A method has been worked out for the conversion of squ.id waste into meal. The waste is boiled in salt solution (2%)/salt (2%) and alumn (0.5%) solution/and water for two minutes, drained and dried. All the dried samples including the control (dried without blanching) were analysed for physical and biochemical changes. Blanching reduced the yield but the product could be dried in a shorter period. The volatile bases were reduced significantly and the colour was improved. Blanching made pulverisation of the dried product easy. Pulverisation before drying yielded a granular product.

Studies on the chemical and nutritional quality of protein powders isolated from shrimp waste

Protein powders were prepared from processing waste of prawns either by mechanically squeezing the shell and freeze drying the resultant aqueous extract or by treating the shell with 0.5% sodium hydroxide, filtering it and freeze drying the filtrate. Comparative studies on the proximate composition, amino acid profile, consumer acceptability and nutritional quality of the protein powders showed that the product prepared by freeze drying of the press liquor obtained by passing the waste through a hand operated expeller is better in all aspects studied than the product prepared by mild alkali extraction.

Ecological impact of Mahshahr petrochemical activities on abundance and diversity of macrobenthic fauna in Zangi Creek (Persian Gulf)

The Moosa Creek extends from its opening into the Persian Gulf, with some sub narrow creeks leading to it. Zangi creek is one of the main branches of Moosa creek. The creek contains numerous sources of organic pollution, including sewage outlet flows and boat waste. After establishing the Petrochemical special Economic Zone (PETZONE) in 1997 near to the Zangi Creek, the pipelines, streets and railway made it distinct from eastern and western parts of this creek. Industrial activities have released sludge and effluents in this creek along these years. A survey of the Zangi creek was performed, assessing water properties, organic pollution, and the population density, distribution and diversity of macrobenthic fauna through bi-monthly sampling from July 2006 to September 2007. Samples were collected from water near the bottom and sediment at 7 stations include 2 stations inside the distinct Zangi creek and 4 stations along a transect with 1 km distances between them in eastern free part and one reference station located at the Persian Gulf entrance to the Moosa creek. The environmental parameters such as temperature, salinity, pH, dissolved oxygen, COD, turbidity, EC and heavy metals include Hg, Cd, Pb, Ni as well as percentage silt-clay and total organic matter of the sediment were measured. The faunal population density and their distribution are discussed in relation to the environmental changes. Results showed spatial heterogeneity in faunal distribution of the Zangi creek. Nine groups of macrofauna were identified out of distinct zangi creek. Polychaets formed the dominant group (48%) followed by bivalves (13%), gastropods (10%), Decapods (2%), Tanaids (5%), and all other groups (22%). The distinct creek was heavily polluted without any macrofauna communities probably as a consequence of the high pH, COD, low salinity and heavy metals contamination specially Cd and Pb. The other stations near to the disposal site were found with macrofauna communities commonly tolerant to organic pollution, At 3 km east of the disposal site, macrofauna is comparable to the surrounded creek, whereas macrofauna still indicate environmental degradation. Farther a way, faunal density decreases and equilibrium taxa gradually replace opportunistic species, while the other stations were far from polluted area contained lower pollution and relatively healthy macrofauna. The mean biomass of macrobenthic fauna were estimated for the whole studied area. The results are considered in Minimum density and biomass in surrounded creek and maximum density and biomass in 3 km of surrounded area. Biodiversity Indices were low in surrounded creek. The Shanon-weaver information index was used to describe the spatially variations in diversity. Macrofauna density, shanon and simpson index were significantly variable between surrounded and free parts of Zangi creek (p<0.05). The numerical abundance of macrobenthose varied from 221. m-2 in polluted area to 4346 m-2 in free part of Zangi creek. The Shanon-weaver information index varied from 0.4 in distinct area to 2.9 in reference station. The physico- chemical changes between distinct and free creeks showed significant variations such as pH, salinity and EC. Salinity and EC were significantly positive correlate to macrofauna density, whereas pH and TOM percentage indicated significantly negative correlation to density. Heavy metals concentrations in sediments were higher than water samples. Concentration pattern of heavy metals in sediments and water samples were Ni>Pb>Cd>Hg. Salinity and pH were significantly correlated to metals in sediments (p<0.01). No significant correlation were found between Macrofauna density and heavy metals (p<0.05).