Arsenite Resistance, Accumulation, and Volatilization Properties of Trichoderma asperellumSM‐12F1, Penicillium janthinellumSM‐12F4, and Fusarium oxysporum CZ‐8F1

Abstract

It is expected that microorganisms capable of arsenic (As) accumulation and volatilization can be used to remediate As‐contaminated environments. In this paper, the arsenite [As(III)] resistance, accumulation, and volatilization properties of Trichoderma asperellum SM‐12F1, Penicillium janthinellum SM‐12F4, and Fusarium oxysporum CZ‐8F1 were investigated. The results indicated that all three fungal strains exhibited significant As(III)‐resistance. After being exposed to 40 and 80 mg/L As(III) for five days, the dry mycelium weights of P. janthinellum SM‐12F4 and F. oxysporum CZ‐8F1 were significantly increased compared to the controls. The spiked As(III) initially inhibited and subsequently promoted fungal growth (mainly in the logarithmic growth phase). The maximal biomasses of 0.25, 0.29, and 0.29 g for T. asperellum SM‐12F1, P. janthinellum SM‐12F4, and F. oxysporum CZ‐8F1 after exposure to As(III), respectively, were all higher than their corresponding controls without As(III). When exposed to 40 mg/L As(III) for five days, the efficiencies of As(III) accumulation for T. asperellum SM‐12F1, P. janthinellum SM‐12F4, and F. oxysporum CZ‐8F1 were 53.02, 13.67, and 13.65 µg/g/day, respectively, and the efficiencies of As(III) volatilization were 51.87, 54.34, and 46.35 µg/g/day, respectively. It seems that these fungal strains can be used in the future to tackle As‐contaminated environments.

Arsenic speciation transformation and arsenite influx and efflux across the cell membrane of fungi investigated using HPLC–HG–AFS and in-situ XANES

“…2b, d, and f). This result is consistent with our previous report (Feng et al, 2013), which indicated that As(III) can be adsorbed onto and accumulated into fungal cells. It is known that As(III) can bind to many chelating proteins or peptides containing thiol ligands, such as glutathione (GSH), phytochelatins (PCs), and metallothioneins (MTs) to form inactive complexes (Cobbett and Goldsbrough, 2002;Ngu et al, 2008).…”

“…The As accumulation and volatilization abilities of three fungal strains, Trichoderma asperellum SM-12F1, Penicillium janthinellum SM-12F4, and Fusarium oxysporum CZ-8F1, have been detailed in previous reports (Zeng et al, 2010;Feng et al, 2013). The possible speciation of As in these fungal cells has been studied after exposure to arsenate [As(V)] (Su et al, 2011(Su et al, , 2012, which is a ubiquitous specie of As in oxic environments.…”

“…The speciation transformation dominated by microorganisms can greatly influence the toxicity and mobilization of As. Furthermore, the biochemical responses of microorganisms to As vary due to their different physiological characteristics (Feng et al, 2013). The different chemical species of As may activate differential responses in the same microbial organism (Matia-González and Rodríguez-Gabriel, 2011).…”

Immobilization of As(V) in Rhizopus oryzae Investigated by Batch and XAFS Techniques

“…Fungal resistance to As(V) in the environment has a certain tolerance threshold, and As(V) concentrations higher than the threshold value may affect the growth of fungi. 27 …”

“…Microorganisms have evolved various mechanisms to deal with As toxicity, including reducing the number of intracellular As molecules and biotransformation of As species by oxidation, reduction, and methylation. 27 , 28 It is reported that fungi living in As-contaminated sites have evolved different cellular and molecular systems to survive and have unique merits, such as high bioaccumulation and tolerance to As, high cell wall binding capacity, and high intracellular As uptake capacity. 29 − 32 To date, the bioaccumulation and tolerance of As(V) by fungi have been extensively reported upon, 33 − 35 whereas less information about fungal immobilization for As(V) bioremediation is available.…”