Growth promotion of Chlorella ellipsoidea by co-inoculation with Brevundimonas sp. isolated from the microalga

Abstract

Eight bacterial strains identified as P1, P2, Y1, Y2, W1, W2, G, and R were isolated from a longterm laboratory culture of the green alga Chlorella ellipsoidea. Although it is unknown how these bacterial strains have been maintained with the C. ellipsoidea culture, all appeared to promote the growth of C. ellipsoidea. Co-inoculation of each bacterial strain with C. ellipsoidea resulted in 0.5-3 times greater algal growth than that of C. ellipsoidea alone. The most effective bacterium (i.e., strain P1) was selected and further characterized. Biochemical analysis and transmission electron microscopy revealed that strain P1 is closely related to the genus Brevundimonas. Sequence analysis of the 16S rRNA of strain P1 showed 99.9 and 99.4% nucleotide sequence identity to that of B. nasdae and B. vesicularis, respectively. In addition to the growth promotion of C. ellipsoidea by strain P1, the growth of strain P1 was also significantly enhanced by co-culturing with C. ellipsoidea, indicating a symbiotic relationship between the bacterium and alga. Scanning electron microscopy showed the direct adhesion of strain P1 cells to the surface of C. ellipsoidea cells, as well as the development of abundant crinkles on the surface of co-cultured C. ellipsoidea cells.

Effect of bacteria on growth and biochemical composition of two benthic diatoms Halamphora coffeaeformis and Entomoneis paludosa

“…It is currently accepted that bacteria can positively or negatively affect microalgal growth performance (Cole, 1982;Le Chevanton et al, 2013;Natrah et al, 2014;Park et al, 2008). In the present study, both higher diatoms growth rates and cell division were related to the highest bacterial abundance, a positive interaction already observed for Thalassiosira rotula (Grossart and Simon, 2007) and Skeletonema costatum (Grossart et al, 2006b) in culture.…”

Advanced nutrient removal from surface water by a consortium of attached microalgae and bacteria: A review

“…Roeselers et al (2007) reported that substrate precolonization by Betaproteobacteria accelerated the growth and adhesion of Microcoleus vaginatus to polycarbonate surfaces. Similarly, Park et al (2008) found that the addition of Brevundimonas sp. to Chlorella ellipsoidea prolonged its exponential growth phase and resulted in 50 times greater biomass yield, and Brevundimonas sp.…”

Enhancing Algal Biomass and Lipid Production through Bacterial and Fungal Co-Culture

“…These results are the first to indicate that bacterial exudates can account for the simultaneously stimulation of biomass and lipid production in algae (Park et al 2008). There were no significant differences in biomass and lipid content of the co-culture in contrast to the initial results from the preliminary screening (section 3.3.1).…”

“…To further elucidate the nature of bacteria-algae relationships, the effects of a bacterial-cell free filtrate was tested on algae culture and found that bacterial exudates accounted for much of the observed growth increase in the algae (Park et al 2008). Though it is understood that bacteria synthesize organic substances that may stimulate algal growth, it remains unclear whether these exudates can stimulate lipid production as well.…”

“…Yeast extracellular compounds could have also accounted for either stimulation or inhibition of algae cell and lipid growth. The demonstrated reduced growth in the algae may be caused by the lack of production of bacterial growth-promoting compounds or inhibition by cellular exudates (Fukami et al 1997;Park et al 2008). Bacteria sp.…”