Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris

Abstract

In this research, the effect of solar irradiance on Chlorella vulgaris cultivated in open bioreactors under greenhouse conditions was investigated, as well as of ratio of light intensity in the 420–520 nm range to light in the 580–680 nm range (I420–520/I580–680) and of artificial irradiation provided by red and white LED lamps in a closed flat plate laboratory bioreactor on the growth rate and composition. The increase in solar irradiance led to faster growth rates (μexp) of C. vulgaris under both environmental conditions studied in the greenhouse (in June up to 0.33 d−1 and in September up to 0.29 d−1) and higher lipid content in microalgal biomass (in June up to 25.6% and in September up to 24.7%). In the experiments conducted in the closed bioreactor, as the ratio I420–520/I580–680 increased, the specific growth rate and the biomass, protein and lipid productivities increased as well. Additionally, the increase in light intensity with red and white LED lamps resulted in faster growth rates (the μexp increased up to 0.36 d−1) and higher lipid content (up to 22.2%), while the protein, fiber, ash and moisture content remained relatively constant. Overall, the trend in biomass, lipid, and protein productivities as a function of light intensity was similar in the two systems (greenhouse and bioreactor).

Macromolecular characterization and growth kinetics of Arthrospira platensis and Chlorella Vulgaris as affected by different media (synthetic and Anaerobic Digestor Effluent) - A comparative study.

“…Previous studies 26 also reported that higher light intensity contributes to higher biomass production due to increased light utilization for photosynthesis. Since the cultures grown on ADE media were given higher light than the F/2 medium, it could be the reason for higher biomass.…”

Influence of light on biomass and lipid production in microalgae cultivation

“…cultured using photobioreactor (35 L working volume) with red:blue LED of 8:2 was reported to yield 600 mg TSS/L on day 10 (Pozza et al., 2012). Chlorella vulgaris grown in a closed flat plate bioreactor (25 L working volume) with red and white LED (I 420–520 /I 580–680 ) at increased light intensity obtained faster growth (µ = 0.36 d −1 ) and higher lipid content (22.2%) (Metsoviti et al., 2020). Mixed microalgae cultured in plexiglass photobioreactor (16 L working volume) using red LED has a specific growth rate of 0.109 d −1 (Mohammed et al, 2014).…”

Zagrożenia środowiska i bezpieczeństwo żywności t.1

“…Inne to heterotrofy żyjące w ciemnościach, wytwarzają biomasę dzięki organicznym źródłom węgla. Mikroalgi są z powodzeniem wykorzystywane w przemyśle spożywczym i kosmetycznym [Metsoviti i in. 2020].…”

“…o większej mocy promieniowania na jednostkę powierzchni przy zachowaniu takiej samej długości fali, powoduje szybszy wzrost Chlorella vulgaris w obu hodowlach, a także zwiększa zawartość lipidów w poszczególnych mikroalgach. Wzrost przyspieszył, a zawartość lipidów zwiększyła się również w przypadku zastosowania czerwonych i białych lamp LED [Metsoviti i in. 2020].…”