Nghiên cứu điều kiện lưu giữ thích hợp ba loài vi tảo biển sử dụng ương ấu trùng cầu gai sọ dừa (<i>Tripneustes gratilla</i>) và hải sâm vú (<i>Holothuria nobilis</i>)

Abstract

Currently, the long-term preservation of several important marine microalgae species is essential for aquaculture hatcheries to proactively secure a source of live feed. Three species of marine microalgae, Nannochloropsis oculata, Chaetoceros muelleri, and Isochrysis galbana, were tested in liquid and semi-liquid storage at 7–10°C in complete darkness, and compared with subculturing under normal conditions. The quality of the algae after preservation was evaluated through biomass recovery, morphology, color, and effectiveness as feed for sea urchin larvae (Tripneustes gratilla) and teatfish  sea cucumbers (Holothuria nobilis). Results showed that Nannochloropsis oculata had the best preservation ability in semi-liquid conditions, lasting up to 6 months, while Chaetoceros muelleri was suitable for preservation for 3 months. Isochrysis galbana did not recover after low temperature storage. The preserved algae were biomass cultivated as food for sea urchin and teatfish seacucumber larvae, achieving survival rates and larval size comparable to the continuous cultivation group. The study confirms the feasibility of low temperature, particularly in semi-liquid environments, and proved a stable and cost-effective in microalgae strain preservation suiltabe for hatcheries, contributing to improved efficiency and sustainability in echinoderms breeding.

Keywords: Holothuria nobilis, Tripneustes gratilla, preservation, microalgae