Songserm Rattanaporn, Nishiyama Yoshitaka, Sanevas Nuttha
Department of Botany, Faculty of Science, Kasetsart University, Bangkean, Bangkok 10900, Thailand.
Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama 338-8570, Japan.
Scientifica (Cairo). 2024 Jan 23;2024:1898624. doi: 10.1155/2024/1898624. eCollection 2024.
Light plays a significant role in microalgae cultivation, significantly influencing critical parameters, including biomass production, pigment content, and the accumulation of metabolic compounds. This study was intricately designed to optimize light intensities, explicitly targeting enhancing growth, pigmentation, and antioxidative properties in the green microalga, (KU.B1). Additionally, the study delved into the photosynthetic efficiency in light responses of . The cultivation of was conducted in TRIS-acetate-phosphate medium (TAP medium) under different light intensities of 100, 500, and 1000 mol photons m·s within a photoperiodic cycle of 12 h of light and 12 h of dark. Results indicated a gradual increase in the growth of under high light conditions at 1000 mol photons m·s, reaching a maximum optical density of 1.33 ± 0.03 and a total chlorophyll content of 22.67 ± 0.2 g/ml at 120 h. Conversely, a slower growth rate was observed under low light at 100 mol photons m·s. However, noteworthy reductions in the maximum quantum yield (Fv/Fm) and actual quantum yield (Y(II)) were observed under 1000 mol photons m·s, reflecting a decline in algal photosynthetic efficiency. Interestingly, these changes under 1000 mol photons m·s were concurrent with a significant accumulation of a high amount of beta-carotene (919.83 ± 26.33 mg/g sample), lutein (34.56 ± 0.19 mg/g sample), and canthaxanthin (24.00 ± 0.38 mg/g sample) within algal cells. Nevertheless, it was noted that antioxidant activities and levels of total phenolic compounds (TPCs) decreased under high light at 1000 mol photons m·s, with IC of DPPH assay recorded at 218.00 ± 4.24 and TPC at 230.83 ± 86.75 mg of GAE/g. The findings suggested that the elevated light intensity at 1000 mol photons m·s enhanced the growth and facilitated the accumulation of valuable carotenoid pigment in , presenting potential applications in the functional food and carotenoid industry.
光照在微藻培养中起着重要作用，对包括生物量生产、色素含量和代谢化合物积累在内的关键参数有显著影响。本研究经过精心设计，旨在优化光照强度，明确目标是提高绿色微藻（KU.B1）的生长、色素沉着和抗氧化性能。此外，该研究还深入探讨了（KU.B1）在光照响应中的光合效率。（KU.B1）的培养在TRIS - 醋酸盐 - 磷酸盐培养基（TAP培养基）中进行，在12小时光照和12小时黑暗的光周期内，设置100、500和1000 μmol光子 m⁻²·s⁻¹ 不同光照强度。结果表明，在1000 μmol光子 m⁻²·s⁻¹ 的高光条件下，（KU.B1）的生长逐渐增加，在120小时时达到最大光密度1.33 ± 0.03，总叶绿素含量为22.67 ± 0.2 μg/ml。相反，在100 μmol光子 m⁻²·s⁻¹ 的低光条件下观察到生长速率较慢。然而，在1000 μmol光子 m⁻²·s⁻¹ 下观察到最大量子产率（Fv/Fm）和实际量子产率（Y(II)）显著降低，这反映了藻类光合效率的下降。有趣的是，在1000 μmol光子 m⁻²·s⁻¹ 下的这些变化与藻类细胞内大量β - 胡萝卜素（919.83 ± 26.33 mg/g样品）、叶黄素（34.56 ± 0.19 mg/g样品）和角黄素（24.00 ± 0.38 mg/g样品）的显著积累同时发生。尽管如此，值得注意的是，在1000 μmol光子 m⁻²·s⁻¹ 的高光条件下，抗氧化活性和总酚类化合物（TPCs）水平下降，DPPH测定的IC值记录为218.00 ± 4.24，TPC为230.83 ± 86.75 mg GAE/g。研究结果表明，1000 μmol光子 m⁻²·s⁻¹ 的升高光照强度促进了（KU.B1）的生长，并促进了有价值的类胡萝卜素色素的积累，在功能性食品和类胡萝卜素行业具有潜在应用。
