The ubiquitous problem of pesticide in aquatic environment are receiving worldwide concern as pesticide tends to accumulate in the body of the aquatic organism and sediment soil, posing health risks to the human. Many pesticide formulations had introduced due to the rapid growth in the global pesticide market result from the wide use of pesticides in agricultural and non-agricultural sectors. The occurrence of pesticides in the water body is derived by the runoff from the agricultural field and industrial wastewater. Soluble pesticides were carried away by water molecules especially during the precipitation event by percolating downward into the soil layers and eventually reach surface waters and groundwater. Consequently, it degrades water quality and reduces the supply of clean water for potable water. Long-time exposure to the low concentration of pesticides had resulted in non-carcinogenic health risks. The conventional method of pesticide treatment processes encompasses coagulation-flocculation, adsorption, filtration and sedimentation, which rely on the phase transfer of pollutants. Those methods are often incurred with a relatively high operational cost and may cause secondary pollution such as sludge formation. Advanced oxidation processes (AOPs) are recognized as clean technologies for the treatment of water containing recalcitrant and bio-refractory pollutants such as pesticides. It has been adopted as recent water purification technology because of the thermodynamic viability and broad spectrum of applicability. This work provides a comprehensive review for occurrence of pesticide in the drinking water and its possible treatment.

Utilization of microbes including white-rot fungi and bacterial strains for decolorization of synthetic dyes is one promising strategy of an environmentally friendly and cost-competitive alternative to physicochemical decomposition processes for treating industrial effluents. In this study, the biodegradation ability of the white-rot fungi Polyporus sp. S133 that produce high laccase was investigated in order to decolorize anthraquinone-type dye. Parameter including pH, temperature, and non-ionic surfactant were used to comparatively study the decolorizing effects on Remazol Brilliant Blue R (RBBR). The purified laccase totally decolorized 200 mg L −1 initial concentration of RBBR dye when only 1.5 UL −1 of laccase was used in the reaction mixture. The optimal decolorization rates were achieved at pH 5 and at a temperature of 50°C. N-hydroxybenzotriazole, a small molecular weight redox mediator, was found to accelerate the decolorization. Tween 20 inhibited the decolorization while Tween 80 and Brij 35 showed no inhibition effect. Two compounds were identified as the intermediates (m/z 304.3 and m/z 342.2). These results suggest that laccase from Polyporus sp. S133 is a powerful tool for the decolorization of anthraquinone dyes. A pathway for the metabolism of the RBBR by laccase of Polyporus sp S133 was proposed. These proposed pathways could contribute to a better comprehension of the mechanisms used by oxidative enzymes to transform organic compounds.

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A newly isolated white-rot fungus, Armillaria sp. strain F022, was isolated from the decayed wood in a tropical rain forest. Strain F022 was capable of decolorizing a variety of synthetic dyes, including azo, triphenylmethane, and anthraquinone dyes, with an optimal efficiency of decolorization obtained when dyes added after 96 h of culture, with the exception of Brilliant Green. All of the tested dyes were decolorized by the purified laccase in the absence of any redox mediators, but only a few were completely removed, while others were not completely removed even when decolorization time was increased. The laccase, with possible contributions from unknown enzymes, played a role in the decolorization process carried out by Armillaria sp. F022 cultures, and this biosorption contributed a negligible part to the decolorization by cultures. The effect of dye to fungal growth was also investigated. When dyes were added at 0 h of culture, the maximum dry mycelium weight (DMW) values in the medium containing Brilliant Green were 1/6 of that achieved by the control group. For other dyes, the DMW was similar with control. The toxic tolerance of dye for the cell beads was excellent at least up to a concentration of 500 mg/l. The optimum conditions for decolorization of three synthetic dyes are at pH 4 and 40°C.

The bioremediation potential of crude oil by Polyporus sp. S133 pre-grown in wood meal was investigated in two separate experiment trials; liquid medium and soil. The effect of three nutrients (glucose, polypeptone, and wood meal), oxygen flow, and some absorbent on the efficiency of the process was also evaluated. Degradation of crude oil in soil was significantly increased with an addition of oxygen flow and some absorbent (kapok and pulp). The highest degradation rate of crude oil was 93% in the soil with an addition of 10% kapok. The present study clearly demonstrates that, if suitably developed, Polyporus sp. S133 could be used to remediate soil contaminated with crude oil.