Study On The Active Metabolites In Algae And Algae Application

In this paper,five species of algae were preliminarily studied.At the end,Gelidium amansii was chosen for its more active metabolites.A variety of chromatographic techniques were used to separate and purify the metabolites in Gelidium amansii,and the separated and purified structures were analyzed.A Gelidium amansii product was made to conduct preliminary research.The main results of the research are shown as follows:1.Preliminary screening of metabolites in five types of algae was carried out by chemical screening methods(thin layer chromatography,high performance liquid chromatography,gas chromatography-mass spectrometry).According to the analysis of TLC,it was found that Gracilaria tenuistipitata and Gelidium amansii had obvious coloration and rich metabolites.According to the analysis of HPLC,the ethyl acetate phase metabolites of Gelidium amansii were found that it was easy to extract and separate compounds with certain research value.According to the analysis of GC-MS,there were many complex types of components in petroleum phase of Gracilaria tenuistipitata and Gelidium amansii.Many types of unknown compounds were also not found in them.2.Biological screening methods(antibacterial activity test,DPPH free radical scavenging ability test)were used to preliminarily screen five marine algae.The antibacterial activity of Gelidium amansii was demonstrated by the inhibition zones of ethyl acetate extracts against Staphylococcus aureus and Vibrio furnissii were 7.6±0.4 mm and 8.9±0.1 mm,respectively.The inhibition zones of petroleum ether phase extracts in Gelidium amansii against Staphylococcus caureus and Vibrio furnissii were 8.5±0,5 mm and 14.0±0.8 mm,respectively.The DPPH free radical scavenging ability of Gelidium amansii was demonstrated as ICso value of the aqueous phase was 12.618 mg/mL;IC50 value of the petroleum ether was 8.978 mg/mL;IC50 value of the ethyl acetate phase was 3.777 mg/mL.Through chemical screening and biological screening,Gelidium amansii was eventually selected as an in-depth study subject.3.A total of 24 compounds were isolated from the crude petroleum ether and ethyl acetate extracts of Gelidium amansii by silica gel column chromatography,gel column chromatography,and high performance liquid chromatography.Four compounds were first identified from petroleum ether phase in Gelidium amansii by data analysis of nuclear magnetic.Four known compounds are Phytene-1,2-diol,Parguesterol A,6-hydroxy-cholest--4-ene-3-one,and cholest-5-en-3,7-diol,respectively.Two known compounds were identified from the ethyl acetate phase in Gelidium amansii,named cholesterol-5-ene-3β,7a-diol and 3-(1-hydrox,yethyl)-4-methyl-lH-pyrrole-2,5-dione.4.Sensory evaluation,low-field NMR,texture,and scanning electron microscopy were used as indexes to study the effects of different amount of solutions of Gelidium amansii in tofu brain.The sensory evaluation found that the highest score of sensory was 20%of Gelidium amansii solutions.The texture analysis showed that the hardness of Gelidium amansii solutions increased with the increase of the added solutions of Gelidium amansii,and its cohesiveness and adhesiveness reached the maximum when the Gelidium amansii solutions were at 40%and 60%,respectively.The low-field NMR and scanning electron microscopy further proved that when Gelidium amansii solutions was added about 40%,the gel properties and the binding to free water were better.