Modeling growth and photosynthetic response in Arthrospira platensis as function of light intensity and glucose concentration using factorial design

Abstract

Combined effect of light intensity and glucose concentration on Arthrospira platensis growth and photosynthetic response was evaluated using a 3 2 factorial design. This design was carried out with light levels of 50, 100, and 150 µmol photons m −2 s −1 and glucose concentrations of 0.5, 1.5, and 2.5 gL −1 . Results from the response surface methodology were that the highest level of light intensity and glucose concentration improved biomass (1.33 gL −1 ), maximum specific growth rate (0.49 day −1 ), and net photosynthetic rate (139.89 µmol O 2 mg Chl −1 h −1 ). Furthermore, the interaction of both factors showed that at low light, glucose had a low effect on maximum biomass and maximal net photosynthetic rate. However, at the highest light levels, the effect of glucose was more sensitive and the increase of glucose concentration increased the levels of all responses. The rates of the instantaneous relative growth, net photosynthesis, and dark respiration of growth cultures showed two different phases in mixotrophic condition. The first was distinguished by the preponderance of the photoautotrophic mode; the second was based mainly on photoheterotrophy.

Lipid production in Dunaliella bardawil under autotrophic, heterotrophic and mixotrophic conditions

“…Organic carbon sources are expected to reduce CO 2 fixation through photosynthesis. In such scenario, while cell division increases, the metabolic cost of respiration may exceed the gain from photosynthesis (Liu et al, 2009;Rym et al, 2010). Photosynthetic microorganisms can use glucose in their metabolism as the final production of photosynthesis.…”

Edible Cyanobacterial Genus Arthrospira: Actual State of the Art in Cultivation Methods, Genetics, and Application in Medicine

“…Mixotrophic cultivation of A. platensis results in higher overall biomass production in any light intensity used compared to autotrophic and heterotrophic cultures (4 klux for (Chen, 1996 ); below 150 μmol m −2 s −1 for (Vonshak et al, 2000 )). Indeed, the maximal biomass yield was 2.3 times greater in mixotrophic conditions under 150 μmol m −2 s −1 light intensity (Rym et al, 2010 ). The results showed that the amount of biomass obtained under mixotrophic conditions was a result of the combined response of cyanobacterium to light and organic carbon source—glucose.…”

“…Mixotrophic cultures also have lower light requirements, higher oversaturation levels and can recover quicker from light stresses than autotrophic cultures (Vonshak et al, 2000 ). Under lower illumination, glucose has a low influence on the maximal biomass concentration and growth rate (Rym et al, 2010 ).…”

A turbidity sensor development based on NL-PI observers: Experimental application to the control of a Sinaloa’s River Spirulina maxima cultivation

“…Spirulina platensis is a microalgae that can produce vast amounts of high pharmaceutical value products such as phycocyanin [1]. Microalgae has been recently found to be able to manage organic carbon nutrients (i.e., glucose and acetate) for the mixotrophic growth and production, where it has shown that this type of multimetabolically sourced culture significantly increases biomass production [2]. However, the excess of microalgae growth becomes a problem in rivers, lakes, and basins in general because such excess is an indirect measure of the level of pollution and eutrophication [3].…”

“…Also, we propose an HG-robust observer to estimate unknown disturbances; this estimation in nonlinear PI control plus compensation (robust PI control) is used to ensure a predefined optimal trajectory. This system is evaluated employing simulations with a nonlinear model and experimental results about S. platensis mixotrophic culture as a function of light intensity and glucose concentration [2,20,21].…”