Biodegradation of malachite green by Pseudomonas sp. strain DY1 under aerobic condition: characteristics, degradation products, enzyme analysis and phytotoxicity

Abstract

Malachite green (MG), a widely-used and recalcitrant dye, has been confirmed to be carcinogenic and mutagenic against many organisms. The main objective of this study is to investigate the capability of Pseudomonas sp. strain DY1 to decolorize MG, and to explore the possible mechanism. The results showed that this strain demonstrated high decolorizing capability (90.3-97.2%) at high concentrations of MG (100-1,000 mg/l) under shaking condition within 24 h. In static conditions, lower but still effective decolorization (78.9-84.3%) was achieved. The optimal pH and temperature for the decolorization was pH 6.6 and 28-30°C, respectively. Mg(2+) and Mn(2+) (1 mM) were observed to significantly enhance the decolorization. The intermediates of the MG degradation under aerobic condition identified by UV-visible, GC-MS and LC-MS analysis included malachite green carbinol, (dimethyl amino-phenyl)-phenyl-methanone, N,N-dimethylaniline, (methyl amino-phenyl)-phenyl-methanone, (amino phenyl)-phenyl methanone and di-benzyl methane. The enzyme analysis indicated that Mn-peroxidase, NADH-DCIP and MG reductase were involved in the biodegradation of MG. Moreover, phytotoxicity of MG and detoxification for MG by the strain were observed. Therefore, this strain could be potentially used for bioremediation of MG.

Biodegradation of malachite green by a novel copper-tolerant Ochrobactrum pseudogrignonense strain GGUPV1 isolated from copper mine waste water

“…The degraded metabolites arising after 24 h of incubation of strain GGUPV1 in BSMY1 medium containing MG (50 mg/L) were extracted with equal volume of ethyl acetate (Du et al 2011). The ethyl acetate fraction was evaporated to dryness and was sent to SAIF, IIT Bombay, Mumbai, India for analysis.…”

“…In control plates, MQ water (20 mL) was used in place of MG solution. After 7 days of incubation, seed germination percentage and radical/ plumule lengths were calculated (Du et al 2011).…”

“…A large number of physiochemical methods are available for treatment of dye wastewater but these methods posses a constraint due to their limited versatility, high cost, low efficiency and interference by other wastewater constituents (Banat et al 1996). These physiochemical methods also produce a lot of sludge posing a threat as secondary pollutant (Du et al 2011). However, biological methods are available which are eco-friendly and completely mineralize organic pollutant (Pandey et al 2007).…”

Malachite green “a cationic dye” and its removal from aqueous solution by adsorption

“…Many treatment technologies have been applied to decolorize MG from aqueous medium, such as biodegradation and decolorization Levin et al 2004;Ren et al 2006;Eichlerová et al 2006;Daneshvar et al 2007a, b;Ayed et al 2008;Ali et al 2009;Wu et al 2009;Cheriaa and Bakhrouf 2009;Ayed et al 2010;Du et al 2011;Khataee et al 2011a, b;Shedbalkar and Jadhav 2011;Hu et al 2011;Abd-El-Kareem and Taha 2012); photocatalytic degradation (Hasnat et al 2003;Kominami et al 2003;Lv et al 2005;Yang et al 2005;Chen et al 2007;Sayılkan et al 2007aSayılkan et al , b, 2008Tayade et al 2007;Wang et al 2008a;Ju et al 2008;Asiltürk et al 2009;Prado and Costa 2009;Bansal et al 2009;Kaneva et al 2010;Liu et al 2010;Bojinova and Dushkin 2011; Maximum wavelength 618 nm Table 2 Applications and toxicity of Malachite green dye…”

NovelCastellaniella denitrificansSA13P as a Potent Malachite Green Decolorizing Strain

“…Several microorganisms capable of degrading malachite green including Chlorella sp., Shewanella sp., and Pseudomonas sp. have been extensively reported [19][20][21][22]. Apparently there is a need to expand novel biological decolorization processes leading to the more efficient clean-up of Malachite Green using a single microorganism.…”