The total content of the rich amino acids in two common red algae

Polysiphonia urceolata andPolysiphonia japonica growing in the Qingdao seashore were determined. The algae powder was hydrolyzed by 6 mol/L HCl at 110°C for 48 h and determined by amino acid analyzer. The content was 25.35% and 24.16%

respectively

much higher than that of some other species. In addition

a nutritive liquid with abundant amino acids was prepared (by the enzymatic hydrolysis method usingPolysiphonia urceolata) as raw material for a kind of health beverage. The dried seaweed was decolored by 0.25% KMnO4 and 0.5% active carbon

then enzymalized. In the selection of enzymalizing condition

the orthogonal experimental design was used. Four factors including kinds of enzyme

quantity of enzyme

temperature and time were studied at 3 levels. According to the orthogonal design results

we can choose an optimal condition: hydrolyzing at 45°C by neutral proteinase (0.25%

w/w) for 2h

adjusting pH to 8.5

then adding trypsin (0.25%

w/w) and hydrolyzing for 2 h. Finally the above solution was alkalized by NaOH and neutralized by casein. After the hydrolyzed liquid was filtered and concentrated

suitable additives were added. The final products contain rich amino acids.