Evaluation of the preservation methods for two microalgal concentrates

Various cryoprotectants and cooling methods were adopted for 3-month preservation of the concentrates of Nannochloropsis oculata (2??109 cells/mL, at 4??C and -18??C) and Spirulina platensis (7% dry weight at -18??C). The results showed that, the highest relative cell activity of N. oculata concentrates preserved for 3 months reached 48.17% of that control (fresh cultured cells) by fast freezing at -18??C without cryoprotectant, which higher than other treatments significantly (P<0.05). Under the same conditions, the loss of protein and EPA in the concentrates of N. oculata had were 3.42% and 2.73%, respectively, The lose of the protein and total fat acids in the concentrates of S. platensis were 4.17% and 19.33%, respectively. Based on the systematic comparison, the method of fast freezing at -18??C without cryoprotectant was determined as the favorable for preservation of the concentrates of N. oculata and S. platensis at low temperature.EI中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)05948-9522