Lutein and β-carotene biosynthesis in Scenedesmus sp. SVMIICT1 through differential light intensities

Abstract

The study evaluated the biosynthesis of lutein and β-carotene by Scenedesmus sp. SVMIICT1 under five different light intensities (50, 250, 500, 750 and 1000 µE/m²/s). Liquid chromatography/mass spectrometry (LC/MS) was used to determine relative quantities of lutein and β-carotene. Relatively, high lutein content of 1.43 ± 0.04 and 0.70 ± 0.02 mg/g was found with 50 and 500 µE/m²/s conditions respectively. β-Carotene content was quantified as 0.15 ± 0.01, 0.1 ± 0.01 and 0.12 ± 0.02 mg/g with 50, 250 and 500 µE/m²/s conditions respectively. The light intensities altered photosystem II and photosystem I. At 50 µE intensity, high chlorophyll content and high photosystem II quantum efficiency (F_V/F_M) was observed. Low F_V/F_M ratio of around 0.3 was detected in high light intensities (750 µE and 1000 µE) due to photoinhibition. Lipid fraction increased with increasing light intensity and the fatty acid profiles were similar in all five conditions.

Keywords: Biosynthesis Pathway; GC/MS; LC/MS; Lipids; OJIP curve.