Empirical and Simulative Evaluations of White Fluorescence-type Light Emitting Diodes as Algal Growing Light Sources Based on the Photosynthetic Oxygen Evolution by <i>Synechocystis</i> spp. PCC6803

Abstract

Recently, applications of light-emitting diodes (LEDs) for enhancing the efficiency of photosynthesis have attracted the attentions by many researchers and agriculturalists. In the present study, we proposed both empirical (experimental) and simulative evaluations of chlorophyll-targeting monochromic and white fluorescence-type LEDs as the light sources for algal photosynthesis based on the evolution of O2 by Synechocystis sp. PCC6803.

Possible Roles of Near-infrared Light on the Photosynthesis in <i>Synechocystis</i> sp. PCC6803 under Solar Simulating Artificial Light

“…In fact, most PIkinetic models are derivatives of MME. Today, MMEderived PJE remains the standards for generation of PIcurves in various algae and phytoplankton (Marra et al, 1985;Nagasawa et al, 2015), and also in higher plant communities (Okamoto et al, 2016).…”

“…Monitoring of dissolved O2 concentration in the cyanobacterium culture For monitoring the evolution of O2 from the cyanobacterium culture, a Clerk-type oxygen electrode (Oxygraph Plus System, Hansatech Instruments Ltd., Norfolk, United Kingdom) was used with some modification of the oxygen electrode chamber as previously described (Nagasawa et al, 2015.). The electrode chamber was covered with black cardboard with an opening (optical window; diameter, 10 mm).…”

“…In contrast, light components not targeting such pigments hardly energize the photosynthesis (while there are recent intensive debate on the roles for green colored light in photosynthesis; Terashima et al, 2009). Although both the spectra of solar ray and SSL ranging between 400 and 700 nm shows broad intensive peaks, the action spectra for photosynthesis suggests that only limited bands reflecting the absorption spectra for Chls are utilized by photosynthesis (Nagasawa et al, 2015). Interestingly, when the plants were exposed to Chl-targeting red light together with the light with wavelength greater than 680 nm (peaking at around 700 nm), higher rate of photosynthesis can be induced (as known as Emerson effect) (Govindjee et al, 1960).…”

“…For studying the natural photosynthesis, several groups employed SSL in place of natural sun light (Nagasawa et al, 2015). Photosynthesis in green plants/algae utilizes the VIS light, after harvesting photons with antenna pigments such as chlorophylls (Chls).…”

New Discussion on Boysen-Jensen's Photosynthetic Response Curves Under Plant Canopy and Proposal of Practical Equations for Monitoring and Management of Canopy Photosynthesis

“…As seen above, even today, MME models (including derived PJE) remain the standards for generation of PIcurves (Marra et al, 1985;Nagasawa et al, 2015). However, we have to view that MME is also a derivative of another well-known biological equation proposed by A. V. Hill (1910) known as Hill's equation (HE):…”