Biodegradation of endocrine disruptor Bisphenol A by Pseudomonas putida strain YC-AE1 isolated from polluted soil, Guangdong, China

Abstract

Background: Bisphenol A is an important organic chemical as an intermediate, final and inert ingredient in manufacturing of many important products like polycarbonate plastics, epoxy resins, flame retardants, fooddrink packaging coating, and other. BPA is an endocrine disruptor compound that mimics the function of estrogen causing damage to reproductive organs. Bacterial degradation has been consider as a cost effective and eco-friendly method for BPA degradation compared with physical and chemical methods. This study aimed to isolate and identify bacterial strain capable to degrade and tolerate high concentrations of this pollutant, studying the factors affecting the degradation process and study the degradation mechanism of this strain. Results: YC-AE1 is a Gram negative bacterial strain isolated from soil and identified as Pseudomonas putida by 16S rRNA gene sequence and BIOLOG identification system. This strain found to have a high capacity to degrade the endocrine disruptor Bisphenol A (BPA). Response surface methodology using central composite design was used to statistically optimize the environmental factors during BPA degradation and the results obtained by significant model were 7.2, 30°C and 2.5% for optimum initial pH, temperature and inoculum size, respectively. Prolonged incubation period with low NaCl concentration improve the biodegradation of BPA. Analysis of variance (ANOVA) showed high coefficient of determination, R 2 and Adj-R 2 which were 0.9979 and 0.9935, respectively. Substrate analysis found that, strain YC-AE1 could degrade a wide variety of bisphenol A-related pollutants such as bisphenol B, bisphenol F, bisphenol S, Dibutyl phthalate, Diethylhexyl phthalate and Diethyl phthalate in varying proportion. Pseudomonas putida YC-AE1 showed high ability to degrade a wide range of BPA concentrations (0.5-1000 mg l − 1) with completely degradation for 500 mg l − 1 within 72 h. Metabolic intermediates detected in this study by HPLC-MS were identified as 4,4-dihydroxy-alpha-methylstilbene, p-hydroxybenzaldeyde, p-hydroxyacetophenone, 4hydroxyphenylacetate, 4-hydroxyphenacyl alcohol, 2,2-bis(4-hydroxyphenyl)-1-propanol, 1,2-bis(4-hydroxyphenyl)-2-propanol and 2,2-bis(4-hydroxyphenyl) propanoate. Conclusions: This study reports Pseudomonas putida YC-AE1 as BPA biodegrader with high performance in degradation and tolerance to high BPA concentration. It exhibited strong degradation capacity and prominent adaptability towards a wide range of environmental conditions. Moreover, it degrades BPA in a short time via two different degradation pathways.

Croceicoccus bisphenolivorans sp. nov., a bisphenol A-degrading bacterium isolated from seawater

“…Bisphenol A (BPA) is widely used in the manufacture of synthetic resin, plastics, polycarbonates and other products [1], and is also a well-known pollutant that shows estrogenic and mutagenic effects and acute toxicity [2]. Due to its low cost and increased environmentally friendliness when compared to physical and chemical methods, bioremediation of BPA has proved to be a promising method in recent years [3]. Several species of BPA-degrading bacteria have been reported, including Achromobacter xylosoxidans [4], Bacillus cereus and Bacillus megaterium [1, 5], Cupriavidus basilensis [6], Sphingobium bisphenolivorans [7], Sphingomonas bisphenolicum [8], Pseudomonas putida [3, 9], and so on.…”

2,2-Bis(4-Hydroxyphenyl)-1-Propanol—A Persistent Product of Bisphenol A Bio-Oxidation in Fortified Environmental Water, as Identified by HPLC/UV/ESI-MS

“…It has to be stressed that p -HAP can be formed from 1,2-bis(4-hydroxyphenyl)-2-propanol (Product 2, Scheme 1 ) as suggested in a number of papers [ 4 , 5 , 7 , 8 , 9 , 11 , 12 , 13 , 14 , 21 , 30 , 31 , 32 ]. Therefore, bio-oxidation of BPA into Product 2 in the environmental water is possible, however, Product 2 is immediately converted into p -HAP (most probably through 4,4′-dihydroxy-α-methylstilbene).…”

“…Therefore, bio-oxidation of BPA into Product 2 in the environmental water is possible, however, Product 2 is immediately converted into p -HAP (most probably through 4,4′-dihydroxy-α-methylstilbene). Furthermore, it has been also suggested that the produced p -HAP is further mineralized [ 4 , 7 , 9 , 11 , 14 , 30 , 32 ], it can explain why further metabolites of p -HAP have not been detected.…”

“…In many studies, the proposed first step of BPA biodegradation pathway is BPA oxidation (bio-oxidation) and formation of two isomers shown in Scheme 1 , namely, 2,2-bis(4-hydroxyphenyl)-1-propanol and/or 1,2-bis(4-hydroxyphenyl)-2-propanol (further referred to as Product 1 and Product 2, respectively, Scheme 1 ) [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ].…”

Polyoxometalates/polymer composites for the photodegradation of bisphenol‐A

“…Due to these harmful and toxic effects, bisphenol-A have captivated the attention of several regulatory agencies, such as the European Food Safety Authority (EFSA) who decreased the tolerable daily intake (TDI) for BA from 50 to 4 μg/kg per bodyweight day. 15 To mitigate the harmful effects of this pollutant on the environment and especially in water, several processes to remove this compound have been developed including adsorption, 16,17 electrochemical process, 18,19 chlorination, 20,21 biodegradation, [22][23][24] and advanced oxidation methods (AOP) which are based on powerful oxidants as the radical • OH. 20 However, in the case of BA chlorination and ozonation, several studies have reported the formation of toxic intermediates.…”