Activity and characterization of mixed organic compounds extracted from Rhodobacter sphaeroides as alternative materials to serum for mammalian cell growth

The potential of Rhodobacter sphaeroides extract as an alternative supplement for cell culture systems

It is essential to identify suitable supplements that enhance cell growth, viability, and functional development in cell culture systems. The use of fetal bovine serum (FBS) has been common, but it has limitations, such as batch-to-batch variability, ethical concerns, and risks of environmental contamination. In this study, we explore the potential of Rhodobacter sphaeroides extract, derived from a probiotic photosynthetic bacterium, as an alternative supplement. Our results demonstrate that the extract from R. sphaeroides significantly improves various aspects of cell behavior compared to serum-free conditions. It enhances cell growth and viability to a greater extent than FBS supplementation. Additionally, the extract alleviates oxidative stress by reducing intracellular levels of reactive oxygen species and stimulates lysosomal activity, contributing to cellular processes. The presence of abundant amino acids, glycine and arginine, in the extract may play a role in promoting cell growth. These findings emphasize the potential of R. sphaeroides extract as a valuable supplement for cell culture, offering advantages over the use of FBS.IMPORTANCEThe choice of supplements for cell culture is crucial in biomedical research, but the widely used fetal bovine serum (FBS) has limitations in terms of variability, ethics, and environmental risks. This study explores the potential of an extract from Rhodobacter sphaeroides, a probiotic bacterium, as an alternative supplement. The findings reveal that the R. sphaeroides extract surpasses FBS in enhancing cell growth, viability, and functionality. It also mitigates oxidative stress and stimulates lysosomal activity, critical for cellular health. The extract's abundance of glycine and arginine, amino acids with known growth-promoting effects, further highlights its potential. By providing a viable substitute for FBS, the R. sphaeroides extract addresses the need for consistent, ethical, and environmentally friendly cell culture supplements. This research paves the way for sustainable and reliable cell culture systems, revolutionizing biomedical research and applications in drug development and regenerative medicine.

Optimized Rhodobacter sphaeroides for the Production of Antioxidants and the Pigments with Antioxidant Activity

The photosynthetic bacterium, Rhodobacter sphaeroides, is a bacterium that can grow in a variety of environments and produces substances with antioxidant effects. In this study, we investigated the culture conditions to increase the production of antioxidants in R. sphaeroides, which can grow under both aerobic and anaerobic conditions. After incubation in the exponential phase and stationary phase under both conditions, a 2,2-diphenyl-1-picrylhydrazyl assay was used to confirm the antioxidant effect. Although the highest antioxidant effect was shown in the stationary phase under aerobic conditions, the antioxidant effect of each cell was found to be greater when cultured under anaerobic conditions. The antioxidant activity of R. sphaeroides was increased by sonication. In addition, the contents of carotenoids and bacteriochlorophyll, which are pigments with antioxidant effects, produced by R. sphaeroides were measured. We confirmed that the content of carotenoids was higher in anaerobic conditions than in aerobic conditions. However, when measuring the content of the bacterium, we found that there was more content in aerobic conditions. Therefore, we confirm that when grown in anaerobic conditions, the antioxidant effect of R. sphaeroides is higher, which suggests that this antioxidant effect comes from the effect of carotenoid.