Iron-dependent mutualism between Chlorella sorokiniana and Ralstonia pickettii forms the basis for a sustainable bioremediation system (original) (raw)

Exploitation of siderophore producing bacteria Acinetobacter soli (MTCC-5918) for lipids and reactive oxygen species in Chlorella variabilis (ATCC- PTA 12198) through co-cultivation

2020

Background Increased iron uptake via siderophores triggers a series of physiological processes and generation of reactive oxygen species (ROS) which causes damage to proteins, lipids, carbohydrates, resulting into micro algal cell lysis. Moreover, there are reports mentioning oxidative stress is a mediator for increased lipid accumulation in microalgae. The main aim of this study is co-cultivation of the bacteria Acinetobacter soli (MTCC- 5918) and the microalgae Chlorella variabilis (ATCC-PTA 12198) under iron limiting conditions and the threshold value of iron that trigger oxidizing stress to microalgae. Further, the ROS generation in the microalgae C. variabilis was determined in terms of OH, SO2 and H2O2 concentration in the cells while co-cultivation. Results The co-cultured biomass contains (45.92 ± 0.74%) lipid content which was about 21% higher than that of the axenically grown microalgae. Carbohydrate content also increased to 40% than that of the control culture. Oxidative...

Exploring the potential of microalgae for the bioremediation of agro-industrial wastewaters

Handbook of Algal Science, Technology and Medicine, 2020

Today, agro-industry is a key economic sector worldwide with a large associated generation of wastewaters. These wastewaters entail a hazard to the environment and a waste of valuable organic matter and nutrients. The use of microalgae to support an efficient and low cost treatment of agro-industrial wastewaters along with a sustainable resource recovery has attracted an increasing attention over the past decades. This book chapter will critically discuss the fundamentals of algal-bacterial symbiosis and photobioreactor design in the context of wastewater treatment. The current challenges in microalgae harvesting and biomass valorization in the form of feedstock for the production of biofertilizers, fish feed, and biogas will be also presented along with a critical evaluation of the sustainability of the process. Finally, the future trends in the field of photosynthetic treatment of agro-industrial wastewater will be outlined.

Oligotrophic Bacteria Enhance Algal Growth under Iron-Deficient Conditions

Applied and Environmental Microbiology, 1995

A Halomonas sp., a marine halophilic and oligotrophic bacterium, was grown on exudates of Dunaliella bardawil. The bacteria increased the solubility of Fe, thereby enhancing its availability to the algae. As a result, the algal growth rate increased. Because of these syntrophic relations, growth of the marine alga D. bardawil was facilitated at Fe levels that would otherwise induce Fe deficiency and inhibit algal growth.