A method for determination of astaxanthin and astaxanthin eaters in shrimp shell by high performance liquid chromatography is established.Shrimp shell are addressed with 5%hydrochloric acid to remove calcium ions.Afte...A method for determination of astaxanthin and astaxanthin eaters in shrimp shell by high performance liquid chromatography is established.Shrimp shell are addressed with 5%hydrochloric acid to remove calcium ions.After shell is dried,organics from shrimp shell are extracted with anhydrous ethanol.The alcohol extrative of the shrimp shell is mixed with the ammonium sulfate to extract astaxanthin by aqueous two-phase extraction.The crude astaxanthin is collected,which is distributed in the middle layer of the aqueous two-phase layer.After distilled water is added to the crude astaxanthin,the aqueous solution is centrifuged,and the previous step is repeated for several times.The precipitation in centrifuge tube is collected and dried.The crude astaxanthin dried is dissolved with acetone,and the sample solution is separated by TLC.Every pigment on the TLC plate is collected and dissolved with acetone.The pigments are determined by high performance liquid chromatograph.The results show that aqueous two-phase system,3 mL alcohol extractive of astaxanthin and 4.5 mL 20%ammonium sulfate,can be used to acquire crude astaxanthin.The wavelength of the maximum peak of astaxanthin in ethanol solution is 472 nm.A variety of pigments can be separated from the crude astaxanthin by thin-layer chromatography,including free astaxanthin,astaxanthin monoester,astaxanthin diester,echinenone and other substances.It can be seen from high performance liquid chromatography that the appearance time of free astaxanthin is from 4 min to 5.5 min,and the appearance time of astaxanthin monoester is from 10.5 min to 27.8 min.The method is simple about the sample pretreatment and feasible about the determination of astaxanthin and astaxanthin esters in shrimp shell.展开更多
One of the bottlenecks for bioproduction of butyric acid as bulk chemical is the difficulty in separating butyric acid from the fermentation broth,compared with the petroleum-based chemical synthesis method.In the pre...One of the bottlenecks for bioproduction of butyric acid as bulk chemical is the difficulty in separating butyric acid from the fermentation broth,compared with the petroleum-based chemical synthesis method.In the present work,a novel separation methodology was developed based on an aqueous two-phase system with inor-ganic salts.Calcium chloride was screened out for effective separation of butyric acid from butyric acid-water-salt systems.Within appropriate concentration range of butyric acid and salt,butyric acid was enriched in the upper phase and most of calcium ions remained in the lower phase.This"salting out"effect is very efficient to separate butyric acid from the simulated butyrate fermentation broth,which consists of butyric acid and acetic acid with concentration ratio of 4︰1,so that the final ratio of butyric acid/acetic acid in the upper phase is improved to 9.87. The aqueous two-phase system was used to separate butyric acid from the actual fermentation broth with satisfac-tory result.展开更多
Phase separation behavior of cocamidopropyl betaine/water/polyethylene glycol （PEG） system was studied. The effects of concentration and molecular weight of PEG on the phase separation behavior were investigated. Cl...Phase separation behavior of cocamidopropyl betaine/water/polyethylene glycol （PEG） system was studied. The effects of concentration and molecular weight of PEG on the phase separation behavior were investigated. Clouding occurred when the concentration of PEG was large enough in the betaine aqueous solution, and the concentration of PEG at cloud point decreased with the increase of PEG molecular weight for a constant betaine concentration. The bottom phase was the PEG-rich phase, and the upper phase was the betaine-rich phase. The volumetric ratio of PEG-rich phase to betaine-rich phase, at the same difference between the PEG concentration and the one at the cloud poim, △Ccp （0.1 g.ml^-1）, decreased as the PEG molecular weight increased and approached 1 for higher PEG molecular Weiglai （about 20000）, which was similar to the typicai-aqueous two-phase system. This volumetric ratio depended on the initial PEG concentration, but independent of PEG molecular weight. The concentration ratio of betaine to PEG in both phases depended on the △Ccp independent of PEG molecular weight.展开更多
基金supported by Liao Ning Revitalization Talents Program No. XLYC1807161Dalian High-level Talents Innovation Support Plan No. 2017RQ063+4 种基金Dalian Ocean University Zhanlan scholar ProgramThe National Natural Science Foundation of China under contract Nos. 41206013, 41430963the Public Science and Technology Research Funds Projects of Ocean under contract No. 201205018the National Science and Technology Support Program under contract No. 2014BAB12B02Projects of Institute of Marine Industry Technology of Liaoning Universities
文摘A method for determination of astaxanthin and astaxanthin eaters in shrimp shell by high performance liquid chromatography is established.Shrimp shell are addressed with 5%hydrochloric acid to remove calcium ions.After shell is dried,organics from shrimp shell are extracted with anhydrous ethanol.The alcohol extrative of the shrimp shell is mixed with the ammonium sulfate to extract astaxanthin by aqueous two-phase extraction.The crude astaxanthin is collected,which is distributed in the middle layer of the aqueous two-phase layer.After distilled water is added to the crude astaxanthin,the aqueous solution is centrifuged,and the previous step is repeated for several times.The precipitation in centrifuge tube is collected and dried.The crude astaxanthin dried is dissolved with acetone,and the sample solution is separated by TLC.Every pigment on the TLC plate is collected and dissolved with acetone.The pigments are determined by high performance liquid chromatograph.The results show that aqueous two-phase system,3 mL alcohol extractive of astaxanthin and 4.5 mL 20%ammonium sulfate,can be used to acquire crude astaxanthin.The wavelength of the maximum peak of astaxanthin in ethanol solution is 472 nm.A variety of pigments can be separated from the crude astaxanthin by thin-layer chromatography,including free astaxanthin,astaxanthin monoester,astaxanthin diester,echinenone and other substances.It can be seen from high performance liquid chromatography that the appearance time of free astaxanthin is from 4 min to 5.5 min,and the appearance time of astaxanthin monoester is from 10.5 min to 27.8 min.The method is simple about the sample pretreatment and feasible about the determination of astaxanthin and astaxanthin esters in shrimp shell.
基金Supported by the National High Technology Research and Development Program of China(2009AA02Z206,2006AA02Z239)the National Basic Research Program of China(2007CB707805)the Ministry of Science and Technology,China
文摘One of the bottlenecks for bioproduction of butyric acid as bulk chemical is the difficulty in separating butyric acid from the fermentation broth,compared with the petroleum-based chemical synthesis method.In the present work,a novel separation methodology was developed based on an aqueous two-phase system with inor-ganic salts.Calcium chloride was screened out for effective separation of butyric acid from butyric acid-water-salt systems.Within appropriate concentration range of butyric acid and salt,butyric acid was enriched in the upper phase and most of calcium ions remained in the lower phase.This"salting out"effect is very efficient to separate butyric acid from the simulated butyrate fermentation broth,which consists of butyric acid and acetic acid with concentration ratio of 4︰1,so that the final ratio of butyric acid/acetic acid in the upper phase is improved to 9.87. The aqueous two-phase system was used to separate butyric acid from the actual fermentation broth with satisfac-tory result.
基金Supported by the National Natural Science Foundation of China （20676069）.
文摘Phase separation behavior of cocamidopropyl betaine/water/polyethylene glycol （PEG） system was studied. The effects of concentration and molecular weight of PEG on the phase separation behavior were investigated. Clouding occurred when the concentration of PEG was large enough in the betaine aqueous solution, and the concentration of PEG at cloud point decreased with the increase of PEG molecular weight for a constant betaine concentration. The bottom phase was the PEG-rich phase, and the upper phase was the betaine-rich phase. The volumetric ratio of PEG-rich phase to betaine-rich phase, at the same difference between the PEG concentration and the one at the cloud poim, △Ccp （0.1 g.ml^-1）, decreased as the PEG molecular weight increased and approached 1 for higher PEG molecular Weiglai （about 20000）, which was similar to the typicai-aqueous two-phase system. This volumetric ratio depended on the initial PEG concentration, but independent of PEG molecular weight. The concentration ratio of betaine to PEG in both phases depended on the △Ccp independent of PEG molecular weight.
