Biomineralisation of fipronil and its major metabolite, fipronil sulfone, by Aspergillus glaucus strain AJAG1 with enzymes studies and bioformulation

Abstract

Fipronil is a phenylpryazole insecticide which is extensively used for the protection of agricultural yields. However, this insecticide poses various threats to the environment. Therefore it is essential to develop an effective method to degrade or eliminate this pollutant from the environment. In this present study, a fungal strain AJAG1 capable of degrading fipronil and its metabolite, fipronil sulfone, was isolated through enrichment technique. Isolated fungal strain was identified as Aspergillus glaucus based upon its morphological, and 18S rRNA sequence analysis. Strain AJAG1 could degrade 900 mg L of fipronil efficiently in both aqueous medium and soil. In addition, fipronil degradation was tested with various kinetic models and the results revealed that biodegradation in aqueous medium and soil was ascertained by pseudo-first order and zero order rate kinetics, respectively. The infrared spectrum of fipronil degraded sample confirmed the formation of esters, nitro, and alkanes groups. A tentative degradation pathway of fipronil by strain AJAG1 has been proposed on the basis of gas chromatography-mass spectrometry (GC-MS) analysis. The lignolytic enzymes activities were studied during fipronil degradation by strain AJAG1. Further, scanning electron microscopy (SEM) was used to examine the surface morphology of strain AJAG1 after fipronil degradation. In the present investigation, bioformulation of strain AJAG1 was developed using low cost materials such as groundnut shell powder, molasses, and fly ash to remediate the fipronil from agricultural field. These results highlight A. glaucus strain AJAG1 may have potential for use in bioremediation of fipronil-contaminated environment.

Species-specific effects of the introduction of Aspergillus nidulans gfdB in osmophilic aspergilli

“…In a previous study by Király et al ( 2020b ), we managed to supplement A. glaucus with A. nidulans gfdB resulting in ’c gfdB strains with considerably increased t BOOH and, to a lesser extent, increased H 2 O 2 , MSB, Congo Red, and CdCl 2 tolerance. Since A. glaucus is a promising enzyme (Tao et al 2010 , 2011 ; Abrashev et al 2016 ; Li et al 2018 ; Takenaka et al 2019 ; Chen et al 2020 ) and polyketide (Cai et al 2009 , 2014 ; Sun et al 2009 ; Wu et al 2017 ) producer and bioremediation (Gajendiran and Abraham 2017 ; Wei and Zhang 2018 ; Zhou et al 2021 ) fungus, and a satisfactory stress tolerance is highly recquired for any industrial fungal strains (Bai et al 2003 ; Li et al 2011 ; Teixeira et al 2011 ; Hagiwara et al 2016 ; Deparis et al 2017 ; Steensels et al 2019 ; Brandt et al 2021 ; Yaakoub et al 2022 ), these observations raised the question if the contribution of A. nidulans gfdB to oxidative stress tolerance could be exploited in other Aspergillus spp. as well.…”

“…Importantly, the xerophilic/osmophilic A. glaucus may also find its industrial fermentation applications in enzyme (Tao et al, 2010 , 2011 ; Abrashev et al 2016 ; Li et al 2018 ; Takenaka et al 2019 ) and aspergiolide A (an anticancer-polyketide) (Cai et al 2009 , 2014 ; Sun et al 2009 ; Wu et al 2017 ) production, and A. nidulans is also a well-known enzyme producer fungus and represents a potential platform for heterologous protein expression (MacCabe et al 2002 ; Kumar 2020 ; Lopes et al 2021 ; Jin et al 2022 ). It is noteworthy that A. glaucus , which has a remarkably high abiotic stress resistance, is also considered a suitable tool in saline-alkaline remediation technologies (Wei and Zhang 2018 ; Zhou et al 2021 ), in the biomineralization of the insecticide fipronil (Gajendiran and Abraham 2017 ), and in the hydrolysis of sugar cane bagasse (Tao et al 2010 ). A. glaucus stress tolerance genes transferred into other organisms can enhance the osmotic stress tolerance of recipient fungi and plants (Liu et al 2014 , 2015 ).…”

Mycoremediation of 17 β‐Estradiol Using Trichoderma citrinoviride Strain AJAC3 along with Enzyme Studies

“…Growth kinetics studies on the degradation of E2 by the fungal strain indicated the depletion of E2 as carbon and energy source . Two sets of flasks containing 100 mL PDB were inoculated with 1 mL of inoculum.…”

Consequences of Arsenic Contamination on Plants and Mycoremediation-Mediated Arsenic Stress Tolerance for Sustainable Agriculture

“…Aspergillus tamarii and Botryosphaeria laricina isolated from the agricultural field previously exposed to endosulfan were tolerant to endosulfan and were able to degrade the toxicant and its harmful metabolites such as endosulfan sulfate, alpha endosulfan, and beta endosulfan by using them as a source of carbon and energy [ 144 ]. A unique strain of A. glaucus was also shown to be capable of metabolizing fipronil and its byproduct, fipronil sulfone, in another investigation [ 145 ]. Some aquatic fungi such as Mucor hiemalis, M. hiemalis EH5, and M. rouxii can accumulate and degrade cyanotoxins as they are tolerant to oxidative stress [ 146 , 147 , 148 ].…”