Isolation and characterization of nutrient dependent pyocyanin from Pseudomonas aeruginosa and its dye and agrochemical properties

Abstract

Pyocyanin is a blue green phenazine pigment produced in large quantities by active cultures ofPseudomonas aeruginosa, with advantageous applications in medicine, agriculture and for the environment. Hence, in the present study, a potent bacterium was isolated from agricultural soil and was identified morphologically and by 16S rRNA sequencing as P. aeruginosa (isolate KU_BIO2). When the influence of nutrient supplements in both King's A and Nutrient media as amended was investigated, an enhanced pyocyanin production of 2.56 µg ml −1 was achieved in King's A medium amended with soya bean followed by 1.702 µg ml −1 of pyocyanin from the nutrient medium amended with sweet potato. Purified pyocyanin was characterized by UV-Vis Spectrophotometer and Fourier-Transform Infrared spectroscopy (FTIR). Furthermore, Liquid Chromatography Mass Spectrum (LCMS) and Nuclear Magnetic Resonance (NMR) confirmed its mass value at 211 and as N-CH 3 protons resonating at 3.363 ppm as a singlet respectively. The isolated pyocyanin displayed remarkable dye property by inducing color change in cotton cloth from white to pink. Lastly, the antifungal activity of test pyocyanin showed inhibition of growth of rice blast fungus, Magnaporthe grisea and bacterial blight of rice, Xanthomonas oryzae at concentrations of 150 and 200 ppm, respectively. Thus, this investigation provides evidence for diverse actions of pyocyanin which are nutrient dependent and are capable of acting on a large scale, by utilizing microbes existing in agriculture wastes, and thus could be used as an alternative source in the making of natural textile dyes with strong durability and a broad spectrum of ecofriendly agrochemicals.Microorganisms are biological agents which help to solve many problems related to health, agriculture and the environment 1-3 . Microorganisms have been the study at interest in recent years because of production of novel secondary metabolites 4 . These metabolites exhibit antimicrobial, antiviral or antitumor as well as anticoagulant properties, and the production of secondary metabolites may have evolved as an alternative strategy to switching off metabolic pathways by various control mechanisms 5-7 . Products of secondary metabolism, such as pigments, could also be of considerable selective advantage since they could eliminate possible microbial competitors 8 .Natural pigments have been obtained and used since long ago, but interest in them has decreased due to toxicity problems. Hence, pigments from microbial sources are good alternatives for various applications 9,10 . Pseudomonas aeruginosa is one of the most commercially valuable organisms, many of which are responsible for producing soluble pigments like pyocyanin (blue), pyoveridin (yellow-green), pyorubin (red) and pyomelanin (brown) 11 . P. aeruginosa produces pyocyanin (N-methyl-1-hydroxyphenazine) which is a water soluble

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

“…In this work, it was possible to obtain a maximum concentration of PYO (3.3 µg mL −1 ) in 40 h using a defined synthetic medium (LB) under optimized conditions in the statistical design. While in other strains of P. aeruginosa , such as KU-BI02, concentrations of 2.560 µg mL −1 have been produced in 72 h using King’s A medium supplemented with soybean seeds [ 17 ]; in strains P. aeruginosa R1 and P. aeruginosa U3, both in King’s A medium, 4.5 µg mL −1 and 2.4 µg mL −1 of PYO were obtained, respectively, at 96 h of incubation [ 5 ].…”

“…Therefore, it is feasible that P. aeruginosa NEJ01R produces enzymes to degrade the high volume of polysaccharides present in nejayote RE fraction with a positive effect on PYO production. Different strains of P. aeruginosa have demonstrated biosynthesis capacity for effluents of biotechnological processes (with complex composition) such as biodiesel production [ 16 ]; raw substrates, such as cottonseed meal, grape seeds, pea pods, taro leaves and olive wastes, hydrolyzed by acids [ 5 ]; and others, such as ground corn kernels, ground soybean seeds, potato cooking water, ground watermelon seeds and groundnut [ 17 ]. Different concentrations of PYO can be obtained in a defined medium such as nutrient broth and King’s A supplemented with 1% of different raw substrates in submerged fermentations with P. aeruginosa KU-BI02.…”

“…Using the same base medium (nutrient broth), the addition of 1% ground soybean also produces 0.1702 μg mL −1 , which increases to 1.702 μg mL −1 when sweet potato cooking water is added. Similarly, minimum concentrations of PYO (0.5106 μg mL −1 ) are obtained using King’s A medium supplemented with ground watermelon seeds until reaching 2.560 μg mL −1 of PYO when the same King’s A medium is supplemented with ground soybean [ 17 ].…”

“…An attractive approach is to use residues as substrates in bioprocesses to obtain value-added molecules. In this way, PYO production by submerged fermentation of P. aeruginosa has been carried out in glycerol (residues of biodiesel production) and a defined medium supplemented with a broad variety of raw materials [ 5 , 16 , 17 ]. One of the options to achieve this goal is the use of wastewaters as a carbon source, which could be considered toxic for the environment, but the use in culture media is an alternative that reduces its polluting and harmful potential, as well as its valorization.…”

Efficacy of indigenous plant growth-promoting rhizobacteria and Trichoderma strains in eliciting resistance against bacterial wilt in a tomato

“…Increasing the usage of synthetic bactericides for control of wilt causes numerous detrimental effects on human health and environment (Satapute et al 2019). Due to the hazards associated with synthetic pesticides, disease managements through biological control are the new developing knowledge and gaining significance in well farming sustainability (De-Britto et al 2020). Biological agents, well defined as living microorganisms, can expressively decrease the plant pathogen density (O'Brien 2017).…”