Bioremoval of the synthetic dye malachite green by marine Trichoderma sp

In the present study, a marine strain of Trichoderma sp was used for degradation of a synthetic dye, malachite green. Individual and interaction effects of the physical and chemical factors that influenced the percentage of dye degradation were tested by response surface methodology. For optimization, enzyme production and dye degradation were assessed under different temperatures (5–40°C), pH values (3–11), yeast extract (5–9 g L(-1)) and incubation period (0–15 days). The optimum conditions found for dye degradation, were 30°C, pH 5.8, 5.81 mg L(-1) yeast extract for an incubation period of 10 days. Whereas for laccase production they were 29°C, pH 5.3, 7.7 mg L(-1) yeast extract for an incubation period of 12 days. It was confirmed that laccase production required the higher nitrogen source. Degradation of dye was confirmed by using analytical techniques such as FTIR, UV–vis spectral and scanning electron microscope analysis. Furthermore, toxicity effect of degraded and undegraded dye solutions was tested with Artemia salina. Hundred percent mortality was observed in undegraded dye solution as against only 2-5% in degraded dye solution. This work proved the potential of marine strain of Trichoderma Hypocrea lixii on dye degradation.