Estimation of optimal culture conditions for Gedaniella panicellus GPYS21 (Fragilariaceae) as a high-yield bioresource for palmitoleic acid and fucoxanthin production

Abstract

Gedaniella panicellus, a marine diatom belonging to the family Fragilariaceae, has not yet been explored for its biotechnological potential. This study aimed to optimize the growth of G. panicellus using response surface methodology and assess its cellular biochemical composition to verify the production of value-added compounds. The strain was identified through morphological and phylogenetic analyses, with optimal conditions of 20.50 °C, pH 7.33, and 42.32 PSU salinity. Its biochemical profile revealed 24.38 % proteins, 33.05 % carbohydrates, and 37.28 % lipids. Fatty acid analysis showed that the G. panicellus produces a high level of palmitoleic acid (62.37 %), exceeding the yields from macadamia nut and other microalgae. Pigment analysis indicated significant fucoxanthin production (9.21 mg/g), along with diadinoxanthin (2.21 mg/g), and β-carotene (0.49 mg/g) contents. Additionally, the strain synthesises various essential and nonessential amino acids. These findings highlight G. panicellus—first recorded in South Korea—as a promising bioresource for palmitoleic acid and carotenoid production, with potential applications in cosmetics and nutraceuticals.