Study On The Isolation,Purification And Application Of Mycosporine-like Amino Acids (maas) In Gracilaria Changii

Mycosporine-like amino acids (MAAs) found in marine organisms， especiallyin the algae is a class of ultraviolet absorption substance. Mycosporine-like aminoacids (MAAs) which play a role of UV absorbing compounds exist in marineorganisms，especially in the algae.They have great applicable value and attract muchattention. In this Paper the structure， properties， biosynthesis of mycosporine-likeamino acids form Gracilaria changii and the technology of Purification and extractionrole in life of MAAs form Gracilaria changii are outlined. Meanwhile， the researchsituation of the MAAs extracted from algae on the activity and nature are alsointroduced. At present， the research on the composition and nature of MAAs in thecommon seaweed of China were done， however，the research on its purification andapplication are studied little. It worth to do deep research on MAAs，that is of greatinstructing significance for highly utilizing of seaweeds.1.To study the constituents and proportion of MAAs from Gracilaria changii ofZhanjiang， MAAs were separated and purified by C-18Sep-Pak SPE andsemi-preparative HPLC.Four mycosporine-like amino acids were found and wereidentified as Palythine，Shinorine，Palythinol and Porphyra-334，with an approximateratio of4.9:1:1.2:9.9，based on the characteristics UV absorption and spectraldata.This paper compared the accuracy of UV and HPLC determination for thecontent of Porphyra-334which was the main component of Gracilaria changii，established fitting curves of two methods.Verified by experiment， ultimatelydetermined the HPLC detection for the main components of MAAs.This research laidthe foundation for the development and use of the UV radiation and anti-oxidativesubstances in the economic algae produced in our country. 2.According to the theory of the orthogonal rotation combination experimentdesign，four factors and five levels of response surface was used to model the reaction.The factors’affection and the optimal reaction conditions were analyzed.The resultsshowed that， Extraction temperature， extraction time，methanol concentration andthe ratio of liquid to solid are the significant factors for the extraction of MAAs. Awell-fitting quadratic polynomial regression model for the degree of MAAs wasestablished after regression analysis with backward elimination and verified by a test.The perfect conditions are: extraction temperature is48.12℃，time is1.85h， ratio ofliquid to solid is34:1(mL:g)， methanol concentration is25%.The predictive bestMAAs extraction rate is4.943mg/g， and the actual extraction rate is4.893mg/g.Experimental values are in good agreement with the prediction， so theaccuracy of response surface regression model has been verified.3.The purification effect of D152， D61，001x7， D001， SA-2ion exchangeresins for MAAs extract was compared. Through the static adsorption experimentshaving the highest adsorption and resolution resin SA-2were screened a， in pH3orso， which have the largest adsorption capacity can reach10.01mg/g for crudeextracting and in alkaline conditions with the highest elution rate.Using Freundlichisotherm simulation ln(qe)bln(Co)+a(qe:balance for adsorption capacity，Co: initialconcentration of the MAAs)，a=1.16，b=1.12.The process parameters of dynamicpurification were determined for the SA-2: the concentration of samples were4mg/mL，pH value was3or so， velocity was2BV/h， time of adsorption was fourhours， eluent was ammonia with the concentration of2%.After purfication the purityof sample was46.2%， the recovery was89%， and the purity of crude extractingsimproved two times than that of before，so this method of purification was good.4.The purified ultraviolet absorption material MAAs were added to sunscreencosmetics， and the product performance including the stability in the lowtemperature，high temperature，natural light and microbial test，the result indicatesthat the product had a stable physical performance and the sensory evaluate ofsunscreen cosmetics wre up to specifications， so it can be used in the skin test.Sun protection factor of samples were measured by ultraviolet spectrophotometer， andthe results showed that samples added MAAs had a higher ultraviolet absorptionvalue than the control group in the area of300-340nm. through the determitnation ofB16melanoma cells in mice toxicity test for Porphyra-334validated Porphyra-334which was the mian component in the Gracilaria changii was security.