Optimal conditions for the biological removal of arsenic by a novel halophilic archaea in different conditions and its process optimization

Abstract

Recently, concerns about arsenic have been increased due to its high acute toxicity to human and serious environmental problems. In this study, the ability of Halorcula sp. IRU1, a novel halophilic archaea isolated from Urmia lake, Iran for arsenic bioaccumulation was investigated and optimized by Taguchi experimental design. The optimum conditions for high arsenic bioaccumulation by Haloarcula sp. IRU1 could be achieved in the presence temperature 40 o C, pH 8 and NaAsO 2 at 90 mg/L. Under optimum conditions, the microorganism was able to perform their desired function with a 60.89 percent removal of arsenic. In conclusion, Haloarcula sp. IRU1 is resistant to arsenic and removes it in different conditions.

Isolation of arsenic accumulating bacteria from garbage leachates for possible application in bioremediation

“…However, the most common environmental oxidation states of arsenic are the pentavalent As (V) and trivalent As (III) forms. As (III) is more toxic than others (3, 4).…”

“…Nowadays, the use of microorganisms in biological removal of toxic compounds, such as arsenic, is potentially important (4). The first step in identifying bacteria with the ability of bioremediation is separation of resistant bacteria to high concentrations of heavy metals (12).…”

“…KL1, with the highest level of tolerance to toxic effects of arsenic (MIC=225 μg/mL), can be primarily considered as an appropriate candidate to resolve arsenic environmental pollution. However, the bioremediation activity of bacteria is greatly affected by several factors (concentration of toxic compounds, pH, contact time, temperature) and optimization of the conditions could result in high biosorption and bioremediation of heavy metals (4).…”

“…Chronic arsenic poisoning in the general population has been widely reported in many regions of the world (4). Thus, elevated arsenic levels have been reported in soils and ground water worldwide.…”

“…Thus, elevated arsenic levels have been reported in soils and ground water worldwide. In drinking water, the maximum arsenic concentration limit recommended by World Health Organization (WHO) is 0.01 mg/L (4, 5). High levels of arsenic in drinking water can affect human health and have immediate toxic effects on them (5).…”