几种大型野生海藻游离氨基酸组成分析

Analysis of free amino acids in several wild seaweed species

为进一步研究海藻游离氨基酸丰富的生物学功能,以适应对野生海藻资源的开发需求,采用高效液相色谱法(HPLC)对黄渤海沿岸常见的野生绿藻(石莼Ulva lactuca)、红藻(日本马泽藻Mazzaella japonica、石花菜Gelidium amansii)和褐藻(海蒿子Sargassum pallidum)的游离氨基酸含量及组成进行了测定与分析。结果表明:4种海藻的游离氨基酸含量和组成存在明显差异,游离氨基酸总量与必需氨基酸含量均以日本马泽藻最高(分别为8.50、0.78 mg/g),其次是海蒿子(分别为7.45、0.69 mg/g)和石花菜(分别为6.84、0.52 mg/g),石莼最低(分别为4.45、0.34 mg/g);石莼、日本马泽藻和石花菜的游离氨基酸分别以组氨酸、丙氨酸和谷氨酸为主,海蒿子则以谷氨酸、天冬氨酸和丙氨酸为主;日本马泽藻和石花菜呈味氨基酸占游离氨基酸的比例分别为89.37%、89.71%,显著高于海蒿子(77.13%)和石莼(31.53%)(P<0.05);4种海藻的游离态必需氨基酸组成也明显不同,日本马泽藻中缬氨酸、蛋氨酸和苏氨酸含量丰富,海蒿子中以亮氨酸、缬氨酸、蛋氨酸为主,石花菜中以蛋氨酸为主,而石莼中苏氨酸和蛋氨酸含量较多,赖氨酸在4种海藻中均较为丰富;缬氨酸和苯丙氨酸在石莼中、苯丙氨酸在石花菜中均未检出。本研究结果可为海藻产业结构调整升级及新种类开发提供基础营养学数据。

The comparative analysis of free amino acids(FAA)was conducted in Chlorophyta including sea lettuce(Ulva lactuca),Rhodophyta(Mazzaella japonica and Gelidium amansii),and Phaeophyta(Sargassum pallidum)by high performance liquid chromatography(HPLC)to meet the development demand of wild seaweed resources and the diverse biological functions of FAA.The results showed that there were significant differences in FAA contents and compositions among the four species of wild seaweed,with the maximal FAA(8.50 mg/g)and essential amino acid(EAA,0.78 mg/g)contents in M.japonica,followed by S.pallidum(7.45 and 0.69 mg/g,respectively)and G.amansii(6.84 and 0.52 mg/g,respectively)and the minimal in sea lettuce(4.45 and 0.34 mg/g,respectively).The maximal contents of histidine(His),alanine(Ala)and glutamic acid(Glu)were observed in sea lettuce,M.japonica and G.amansii,respectively,while Glu,aspartic acid(Asp)and Ala were the substantial amount of FAA in S.pallidum.The M.japonica had 89.37%of flavor amino acid in FAA and G.amansii had 89.71%of flavor amino acid in FAA,significantly higher than S.pallidum(77.13%)and sea lettuce(31.53%)did(P<0.05).There were significant differences in the composition of free EAA among the four species of wild seaweed,rich in valine(Val)in M.japonica,methionine(Met)and threonine(Thr).Leu,Val and Met were in S.pallidum,Met in G.amansii,Thr and Met in sea lettuce,and rich in lysine(Lys)in the four species of seaweed.However,no Val and phenylalanine(Phe)were detected in sea lettuce and no Phe was detected in G.amansii.