Development of a low-cost culture medium for the rapid production of plant growth-promoting Rhodopseudomonas palustris strain PS3

Abstract

Rhodopseudomonas palustris PS3 is one of the purple phototrophic non-sulfur bacteria (PNSB), which have plant growth-promoting effects on various plants. To expand the scale of PS3 fermentation in a time-and cost-effective fashion, the purpose of this work was to evaluate the use of low-cost materials as culture media and to optimize the culture conditions via response surface methodology. Corn steep liquor (CSL) and molasses were identified as potential materials to replace the nitrogen and carbon sources, respectively, in the conventional growth medium. The optimum culture conditions identified through central composite design were CSL, 39.41 mL/L; molasses, 32.35 g/L; temperature, 37.9˚C; pH, 7.0; and DO 30%. Under the optimized conditions, the biomass yield reached 2.18 ± 0.01 g/ L at 24 hours, which was 7.8-fold higher than that under the original medium (0.28 ± 0.01 g/ L). The correlation between the predicted and experimental values of the model was over 98%, which verified the validity of the response models. Furthermore, we verified the effectiveness of the R. palustris PS3 inoculant grown under the newly developed culture conditions for plant growth promotion. This study provides a potential strategy for improving the fermentation of R. palustris PS3 in low-cost media for large-scale industrial production.

Revealing the role of Plant Growth Promoting Rhizobacteria in suppressive soils against Fusarium oxysporum f.sp. cubense based on metagenomic analysis

“…Several works reported that it could promote plant growth by producing indole-3-acetic acid and 5-aminolevulinic acid ( Su et al., 2017 ), encourage resistance stress by producing peroxidase, and significantly affect rice rhizosphere bacterial communities ( Luo et al., 2019 ). The culture method of R. palustris has been investigated using 39.41 ml/L corn steep liquor and 32.25 g/L molasses at temperature 37.9 °C, pH 7.0, and 30% DO ( Lo et al., 2020 ). Other work also reported that the use of landfill leachate with 16.0 g/L total organic carbon and 1.1 g/L total nitrogen could use as medium growth of R. palustris ( Wang et al., 2018 ).…”

From Lab to Farm: Elucidating the Beneficial Roles of Photosynthetic Bacteria in Sustainable Agriculture

“…For large-scale commercial manufacturing, optimizing the fermentation process is an essential step. To develop an optimal fermentation protocol for R. palustris PS3, we evaluated the use of low-cost materials as culture media and optimized the culture conditions via the response surface methodology [187]. We developed a novel medium for R. palustris fermentation with agro-industrial byproducts, i.e., corn steep liquor (CSL) and molasses, as nitrogen and carbon sources [187].…”

“…To develop an optimal fermentation protocol for R. palustris PS3, we evaluated the use of low-cost materials as culture media and optimized the culture conditions via the response surface methodology [187]. We developed a novel medium for R. palustris fermentation with agro-industrial byproducts, i.e., corn steep liquor (CSL) and molasses, as nitrogen and carbon sources [187]. In addition, we applied response surface methodology to determine the optimum fermentation process and the effectiveness of the new fermentation broth was verified by pot experiments [187].…”

“…We developed a novel medium for R. palustris fermentation with agro-industrial byproducts, i.e., corn steep liquor (CSL) and molasses, as nitrogen and carbon sources [187]. In addition, we applied response surface methodology to determine the optimum fermentation process and the effectiveness of the new fermentation broth was verified by pot experiments [187]. Our newly developed medium and process for large-scale industrial production provide a prospective strategy with the benefits of cost and time effectiveness, as well as environmental sustainability.…”

Renewable Hydrogen Fuel from Photofermentation of Glycerol: Enhanced Reviews

“…Additionally, culture condition has been identified as one of the most impacting factors for the photofermentative hydrogen production process. Lo et al reported that delaying in culture growth was observed as a result of unfavorable conditions [38]. Meeting favorable conditions for culture in a process like PF of glycerol to hydrogen it's a huddle needed to be addressed [24].…”