Using different wavelengths and irradiance on the microalgae Acutodesmus obliquus batch culture

Abstract

BACKGROUND: The quality of light, such as wavelength and the intensity affect the performance of algal growth and lipid production. Moreover, these variables also affect the lipids profile. To study the interrelation among these variables, Acutodesmus obliquus (Scenedesmus obliquus UTEX393) a microalga, was cultivated using illumination by light-emitting-diode surface mount device extensions emitting red ( = 620-750 nm), yellow ( = 570-590 nm), green ( = 495-570 nm) and violet ( = 380-450 nm) light. Additionally, each culture was illuminated at different light intensities (I 1 = 8.75, I 2 = 14.22 and I 3 = 19.69 W m −2 ). Finally, all samples were analysed by GC-MS. RESULTS:The results showed: (1) the biomass production is directly proportional to the light intensity, e.g. at I 3 = 19.69 W m −2 violet (36.80 mg L −1 ), yellow (25.49 mg L −1 ) and red (39.44 mg L −1 ) showed the major production; (2) however, the lipids were produced in minor amounts at major violet light intensity (3.64 mg L −1 at I 3 = 19.69 W m −2 ); (3) the major lipids production (20.56 mg L −1 ) was obtained with red light at I 3 = 19.69 W m −2 and (4) A. obliquus, under the parameters established was a good producer of lipids. CONCLUSIONS:The major amount of biomass was obtained at red, yellow and violet light; meanwhile, the low biomass production, using green light, was associated with inefficient absorption of green light by chlorophyll. Additionally, palmitic, linolenic and linoleic were the most produced lipids, establishing a dependence between light wavelength and irradiance with biomass and lipid production. These results support the use of wavelengths and intensities to produce a group of specific lipids according to the needs of different industries.

A multidisciplinary review ofTetradesmus obliquus: a microalga suitable for large‐scale biomass production and emerging environmental applications

“…2018) and irradiance (Hurtado et al . 2019). Moreover, it also can grow under heterotrophic and mixotrophic conditions (Shen et al .…”

“…The ability of microalgae to grow in wastewater is attractive because they provide a pathway for converting chemical contaminants into biomass (Brennan & Owende 2010). T. obliquus is highly tolerant to high temperature (Yang et al 2018) and irradiance (Hurtado et al 2019). Moreover, it also can grow under heterotrophic and mixotrophic conditions (Shen et al 2018;Di Caprio et al 2019), and different nutrient strategies have been evaluated (Papazi et al 2018;Qu et al 2019).…”