Identification of Photosynthetic Pigments extracted from Phaeodactylum tricornutum as High-Value Bioactive Compounds

Abstract

The present study intends to provide information about a promising source of unique bioactive compounds and for choosing the favorable growth conditions of the diatom “Phaeodactylum tricornutum” suited to different applications. P. tricornutum was cultivated in the temperature range of 20-35°C, light intensity range of 275-538 μmolm-2s-1 and aeration rate range of 2.5- 3.5 Lmin-1. P. tricornutum extracts were analyzed in terms of photosynthetic pigment composition in comparison with a well-known green microalgae Chlorella miniata using the C18 column. Lutein, canthaxanthin, β-carotene and chlorophyll a were detected in C. miniata whereas in P. tricornutum extracts, chlorophyll a, zeaxanthin and β-carotene were identified. Quantitatively, P. tricornutum was distinguished to have greater amount of chlorophyll-a (113.66 mgmL-1) while C. miniata was predominated with a β-carotene content (14.20 mgmL-1). Considerable amounts of pigments were encountered in all of the P. tricornutum extracts obtained under the varying growth conditions. As the temperature was increased and the light intensity was decreased, the accumulation of chlorophyll a and β-carotene increased at the highest aeration rate. Conversely, at the highest light intensity of 538 μmolm-2s-1 and an aeration rate of 3.0 to 3.5 Lmin-1, the zeaxanthin content was maximized and limited at the temperature values over 27.5°C.