| The topic of the paper was to find out the solutions on the comprehensive utilization of shrimp shell resources. Before the production of chitin, the astaxanthin in the shrimp shell was recovered as much as possible, at the same time, the protein was separated and extracted, and the calcium components were made into calcium citrate malate which has high absorption availability. So as to improve the technology of comprehensive utilization, economic and social benefits.In this work , the extraction of astaxanthin,the bioactive substances in the shrimp head and shell was studied. The extraction method of astaxanthin was established: the alkali method and organic solvents method were combined to extract astaxanthin, the solvent in the alkali solution was ethanol: water = 4:1, dichloromethane was selected as the extractant of astaxanthin. In view of the influence of sodium hydroxide concentration, temperature, solid to liquid ratio and the time on the extraction of astanxanthin, the single factor experiments were made, and thereout the response surface analysis experiments with response analysis software were designed. The best extraction conditions for astaxanthin were optimized: sodium hydroxide concentration was 1.41mol / L, temperature was 53.72℃, solid to liquid ratio was 8.1:1, time was 23.76h. In this condition, the absorption value of astaxanthin was 1.2048, the concentration of astaxanthin was 3.26μg/mL,which was equivalent to 32.6μg/g dry shrimp shell.TLC was used to purify astaxanthin. Qualitative analyses astaxanthin samples with silica gel G thin layer plates, the optimal developer of TLC was petroleum ether - acetone - methanol, deployment time was 6.5min, retention value (Rf) was 0.43, resolution (R) was 4.8, the spots were clear and had no tailing phenomenon, so it was the best deployment effect. The optimal developer was used as the eluent to purify and separate astaxanthin samples by centrifugal TLC, and the yield rate of astaxanthin products was 36.3%.The purified astaxanthin product was analyzed qualitatively and quantitatively with spectrophotometry, infrared spectroscopy and high performance liquid chromatography. The results were: the structure of the purified astaxanthin products was consistent with the standard sample; the content of astaxanthin in the purified product was 55.44%. The stability of astaxanthin extract was studied systematically. The influence of illumination, temperature, pH, common metal ions on the stability of astaxanthin extract was investigateted. The results show: the direct illumination has the strongest impact on the stability of astaxanthin. It could turn astaxanthin into yellow within two days, and astaxanthin become almost colorless after four days. There has minimal impact on the stability of astaxanthin when it is stored in drug cupboard. Therefore, astaxanthin should be preserved avoiding light. Astaxanthin was more stable at lower temperature, because as the temperature increased, the impact on the stability of astaxanthin increased. Therefore, astaxanthin should be preserved at low temperature.The pH value of astaxanthin extract should be neutral or 7-8. In this scale the astaxanthin extract was the most stable. Different metal ions had different impacts on the stability of astaxanthin extent, in which Cu2 +and Fe2 + had the greatest impacts in the stability. Therefore, the metal ions should be avoided in the extraction and storage of astaxanthin.The remaining solution after the solvent extraction of astaxanthin extract was protein solution. The amount of protein precipitation was at the highest level, 0.0509g/g dry shrimp shell when pH was adjusted to 4.5. The protein content was 64.16%, determined by Kjeldahl method.The main factors in the preparation of calcium citrate-malatein were considered. The single factor experiments of the amount of water, reaction time, reaction temperature was carried out to investigate the optimum conditions. The results displayed: 55℃was the best reaction temperature for preparation of calcium citrate-malatein; 120mL was the best amount of water; 10h was the best response time. The calcium content was 226.89mg/g, determined by atomic spectrophotometer, and the solubility of calcium citrate-malatein was 0.83g/100mL water.The acetyls of Chitin was stripped with strong alkali, the degree of deacetylation of the chitin product was about 83%.
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