【摘要】 <正> 紫菜(Porphyra)是人们喜爱的一种富有营养的食品,其中蛋白质和氨基酸的含量在海藻中是比较高的,它们在紫菜的生理代谢过程中起着相当重要的作用。如在紫菜中约占2％的色素蛋白大部分由氨基酸构成。 近年来,在我国北方和南方都进行着紫菜的大规模全人工采苗和养殖,同时对其进行了广泛的生态学研究。从生产实践的经验得知,紫菜的质量随养殖地区、季节、水质肥更多还原

【Abstract】 Comparative studies were carried out on the seasonal variation of the contents of amino acids in both free and total states in Porphyra yezoensis cultivated in three typical regions with high-, medium- and low-nutrient contents, using the amino acid analyzer.The NH4-N contents in sea water of three culture regions were in the order: high-nutrient region > medium-nutrient region > low-nutrient region, and the contents of total nitrogen, free amino acids and total amino acids in Porphyra varied in accordance with the same order.Of the 16 free amino acids tested the remarkable changes in contents are noticed in alanine, glutamic acid and asprtic acid, decreasing with the growing period from Jan. to Apr. These three amino acids appear to be more active in nitrogen metabolism of Porphyra, a characteristic of this alga. Other free amino acids varied not conspicuously.Among the 18 amino acids in total state the remarkable changes in alanine, gluta mic acid and aspartie acid are also observed as in free state, depending mainly upon the variation of free amino acids contents.In the high-nutrient region some combined amino acids and total nitrogen contents exhibited a slight increase from Jan. to Feb., showing the increase of protein or chromo-protein, but in the low-nutrient region there was no such evidence.In both alcoholic extractive and acid hydrolyzate taurine and cysteic acid were seasonally and quantitatively determined as well.更多还原