Diversity of marine yeasts with high protein content and evaluation of their nutritive compositions

A total of 327 yeast strains from seawater, sediments, mud of salterns, guts of the marine fish and marine algae were obtained. After crude protein of the yeasts was estimated by the method of Kjehldahl, we found that eight strains of the marine yeasts grown in the medium with 20 g l(-1) glucose contained more than 30.4 g protein per 100 g of cell dry weight. The results of routine identification and molecular methods show that they belong to Metschnikowa reukaui, Cryptococcus aureus, Aureobasidium pullulan, Yarrowia lipolytica and Hanseniaspora uvarum, respectively. With the exception of Aureobasidium pullulans 4#2 with nucleic acid of 7.7% (w/w), all other yeast strains contained less than 5.0% (w/w) of nucleic acid. Analysis of fatty acids shows that all the yeast strains tested had a large amount of C-18:0 and C-18:1 fatty acids while analysis of amino acids indicates that the yeast strains tested had a large amount Of essential amino acids, especially lysine and leucine which are very important nutritive components for marine animals.