Comparative study on the physiological differences between three Chaetomorpha species from Japan in preparation for cultivation

Abstract

High cellulose contents have been found in the thalli of species belonging to the green seaweed genus Chaetomorpha, indicating that they have high potential of cultivating for bioethanol production. The aim of this study was to produce critical information as a guide for the selection of suitable Chaetomorpha species from coastal areas of Japan for commercial cultivation. Three common Japanese Chaetomorpha species, Chaetomorpha crassa, Chaetomorpha moniligera, and Chaetomorpha spiralis, were collected from Matsushima Bay, northern Japan. A series of laboratory experiments were set up to compare photosynthesis, nutrient uptake, and growth, and tolerance of high temperature and low salinity. Compared with C. spiralis and C. moniligera, C. crassa exhibited significantly greater photosynthesis and growth, which was likely related to its greater nutrient uptake ability. In addition, C. crassa showed higher survival at high temperatures of 30 and 35 °C, and at low salinities of 8–4 psu. Therefore, due to its greater growth ability and higher physiological tolerance to high temperature and low salinity, C. crassa should be considered a suitable candidate with great potential for mass cultivation.