Chitosan from Squilla

Squilla (Oratosquilla nepa) is abundant along the west coast of India, inhabiting burrows in sand and mud. The species is little used as it possesses little meat. There is great similarity between chemical composition of Squilla and prawn waste, and it is suggested that Squilla could therefore be used for making chitosan, a potential industrial chemical with various uses. Preparation of chitosan, and the general nature of the prepared product, is described.

Protein from Jawla prawn (Acetes spp.) and Squilla (Orato squilla nepa)

A simple method of isolation of protein from jawla prawn and squilla, which does not involve any chemical treatment, is reported. The method consists in blending the jawla prawn/squilla with equal quantity of water, removal of chitinous matter, heating the pulp at 112°C for 15-20 minutes and drying the precipitated protein after filtration.

Water soluble nitrogenous component from squilla (Orato squilla nepa)

A water soluble hygroscopic powder has been isolated from squilla in good yield, ranging from 3.5 to 5.0% of the fresh raw material, by a simple direct method. The process consists of homogenising squilla with an equal quantity of water, removal of chitinous matter from the slurry by filtration, heating the filtrate at 0.7 kg/sq.cm steam pressure for 15-20 minutes, removal of the precipitated protein by filtration and concentration and final drying in vacuum of the filtered cooled liquor. The pale brown powder so obtained consists mainly of peptones and proteoses and has been found to be comparable to BDH peptone for growth of bacteria, ability to serve as source for tryptophan for indole production and to provide substrate for the production of hydrogen sulphide. Comparative studies have been made on similar water soluble fractions from two species of prawns, namely, Metapenaeus affinis and Parapenaeopsis stylifera.

Squilla protein: chemical composition and nutritive value

Protein extract prepared from squilla (Grato squilla nepa), a commercially unexploited crustacean, was analysed for crude protein and essential amino acids. All the essential amino acids except tryptophan and threonine were present in nutritionally adequate amounts. The protein was evaluated for its nutritional quality in respect of growth rate, protein efficiency ratio (PER) and liver nitrogen content by feeding on rats. Growth rates and protein efficiency ratios were similar in rats fed on casein, squilla protein and a combination of squilla protein and casein (1:1) diet. The weight of liver and kidneys were normal.

Deux nouvelles espèces Indo-Pacifiques de Stomatopodes

In the Indo-pacific region, a study on Stomatopodes revealed two new species: Squilla carinata and Gonodactilus tweediei. Here the author gives a brief description.