• ALGAE
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• v.27 no.2
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• pp.135-137
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• 2012

The stalks of the eustigmatophyte $Pseudocharaciopsis$ $minuta$ were examined by light and scanning electron microscopy. Light microscopy revealed orange-red granules at the base of the stalk. Energy dispersive X-ray microanalysis of the bases indicated that they were mainly composed of manganese. Manganese has not been previously reported from eustigmatophytes. This study indicates that the Eustigmatophyceae needs further study into many aspects of the biology.

• Ocean and Polar Research
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• v.37 no.1
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• pp.61-71
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• 2015

Eicosapentaenoic acid (EPA) produced from marine organisms is widely used in nutraceuticals. Monodus subterraneus and Nannochloropsis oceanica, which are representative freshwater and marine Eustigmatophyceae, respectively, are known to have a high content of protein and lipid, particularly, EPA. In this study, to compare the growth and nutritional composition of M. subterraneus and N. oceanica, they were cultured in autotrophic and mixotrophic conditions with JM and f/2 medium, respectively, at $25^{\circ}C$. In addition, $80{\mu}mol\;photons\;m^{-2}s^{-1}$ with 24-hour and 12-hour light was provided, with the addition of 2% glucose to the medium for the mixotrophic culture. With regard to growth, M. subterraneus showed 10 times higher biomass in a mixotrophic culture than in an autotrophic one. However, no significant difference was observed for N. oceanica between the two culture methods. With respect to nutritional composition, M. subterraneus cultured autotrophically had a higher protein and lipid content, particularly EPA, than that cultured mixotrophically, but no significant difference was found in the two cultures of N. oceanica. Furthermore, M. subterraneus cultured autotrophically with continuous light showed higher nutritional composition, particularly EPA, than N. oceanica. In conclusion, the mass culture of freshwater M. subterraneus is much easier and more economical than marine N. oceanica. In addition, production of EPA will be economically improved if mixotrophic culturing of M. subterraneus is first conducted to maximize the biomass, and then secondary autotrophic culturing is performed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.770-775
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• 2014

The green microalga of the genus Nannochloropsis (class Eustigmatophyceae) is a leading candidate for biofuel production due to its ability to accumulate high oil content (28.7% of cellular ash-free dry weight). We investigated the anti-inflammatory and anticancer activities of sterol-rich fraction from nannochloropsis oculata n-hexane (NOH) extract after saponification of the microalga. Among the fractions with n-hexane, chloroform and ethyl acetate, the n-hexane fraction showed the highest anti-inflammatory activity in LPS-stimulated RAW 264.7 macrophage as well as anticancer activity against human leukemia HL-60 cells without the cytotoxity. And the sterol-rich fraction was obtained from the n-hexane fraction by open silica column under the gradient solvent condition with 100% hexane (1L), hexane : ethyl acetate (20 : 1, 10 : 1, 5 : 1, 1 : 1, v/v). Among the four fractions (NOH-1~4), especially NOH-1 contained the highest content of sterols. NOH1 showed the highest HL-60 (about 85%) and NO inhibitory activities at the concentration of $100{\mu}g/mL$. These results demonstrated that the sterol-rich fraction from N. oculata might be a useful candidate as anti-inflammatory and anticancer agents for anti-inflammatory and anticancer activity.