Optimized Production of a Redox Metabolite (pyocyanin) by Pseudomonas aeruginosa NEJ01R Using a Maize By-Product

Abstract

Pseudomonas aeruginosa metabolizes pyocyanin, a redox molecule related to diverse biological activities. Culture conditions for the production of pyocyanin in a defined medium were optimized using a statistical design and response surface methodology. The obtained conditions were replicated using as substrate an alkaline residual liquid of cooked maize and its by-products. The untreated effluent (raw nejayote, RN) was processed to obtain a fraction without insoluble solids (clarified fraction, CL), then separated by a 30 kDa membrane where two fractions, namely, retentate (RE) and filtered (FI), were obtained. Optimal conditions in the defined medium were 29.6 °C, 223.7 rpm and pH = 6.92, which produced 2.21 μg mL−1 of pyocyanin, and by using the wastewater, it was possible to obtain 3.25 μg mL−1 of pyocyanin in the retentate fraction at 40 h. The retentate fraction presented the highest concentration of total solids related to the maximum concentration of pyocyanin (PYO) obtained. The pyocyanin redox behavior was analyzed using electrochemical techniques. In this way, valorization of lime-cooked maize wastewater (nejayote) used as a substrate was demonstrated in the production of a value-added compound, such as pyocyanin, a redox metabolite of Pseudomonas aeruginosa NEJ01R.

A purified and lyophilized Pseudomonas aeruginosa derived pyocyanin induces promising apoptotic and necrotic activities against MCF-7 human breast adenocarcinoma

“…According to [ 28 ], the addition of 0.2% toluene increases the pyocyanin yield up to 33 μg/ml. In the study performed by [ 29 ], pyocyanin yield using lime-cooked maize wastewater (nejayote) was 3.25 μg/ml by P. aeruginosa NEJ01R. The enhanced pyocyanin production of 2.56 μg/ml was achieved in King’s A medium amended with soya bean followed by 1.702 μg/ml of pyocyanin from the nutrient medium amended with sweet potato [ 30 ].…”

“…Pyocyanin was assessed from different P. aeruginosa clinical isolates as previously described by [ 29 ]. On a cetrimide agar medium, the test strains were grown overnight.…”

Thermal Pyocyanin Sensor Based on Molecularly Imprinted Polymers for the Indirect Detection of Pseudomonas aeruginosa

“…The amount of pyocyanin measured in the sample ( y -axis) can be directly correlated to the amount of bacteria present in the culture sample (Figure b). The HTM results were benchmarked by extracting the bacteria using a 1:1 ratio of King’s A and chloroform, which is then reextracted into an equal volume of HCl 0.2M following the procedure . The obtained solution was diluted 1:4 in HCl 0.2M to obtain the same concentration used for the measurements, then analyzed using a UV–vis spectrophotometer at 520 nm.…”

Biogenic colourants in the textile industry – a promising and sustainable alternative to synthetic dyes

“…After optimisation using a response surface methodology, the dye yield was improved to 3.3 mg•L -1 . 102 Renewable feedstock is one and waste generation another significant advantage. Aqueous growth medium may be disposed into the sewers after the inactivation of microorganisms.…”