Isolation and Identification of Chromium Reducing Bacillus Cereus Species from Chromium-Contaminated Soil for the Biological Detoxification of Chromium

Chromium contamination has been an increasing threat to the environment and to human health. Cr(VI) and Cr(III) are the most common states of chromium. However, compared with Cr(III), Cr(VI) is more toxic and more easily absorbed, therefore, it is more harmful to human beings. Thus, the conversion of toxic Cr(VI) into Cr(III) is an accepted strategy for chromium detoxification. Here, we isolated two Bacillus cereus strains with a high chromium tolerance and reduction ability, named B. cereus D and 332, respectively. Both strains demonstrated a strong pH and temperature adaptability and survival under 8 mM Cr(VI). B. cereus D achieved 87.8% Cr(VI) removal in 24 h with an initial 2 mM Cr(VI). Cu(II) was found to increase the removal rate of Cr(VI) significantly. With the addition of 0.4 mM Cu(II), 99.9% of Cr(VI) in the culture was removed by B. cereus 332 in 24 h. This is the highest removal efficiency in the literature that we have seen to date. The immobilization experiments found that sodium alginate with diatomite was the better method for immobilization and B. cereus 332 was more efficient in immobilized cells. Our research provided valuable information and new, highly effective strains for the bioremediation of chromium pollution.

The Cost Prediction for Chromium Detox Using Foods Intake Containing Glutathione at the Leather Tanning Industry in Magetan, Indonesia

BACKGROUND: Chromium was an organic compound which was used in metal alloys such as stainless steel, chrome plating, metal ceramics, leather tanning, etc. To reduce and eliminate toxin of chromium from the human body could be using detoxification process, one of them was using foods. AIM: The aim was to calculate the foods intake contain glutathione to improve chromium detoxification and calculate the cost of foods intake. METHOD: The type of research was a descriptive study. The subjects were 10 workers. Inclusion criteria of subjects were workers who had worked for more than or equal to 10 years. Variables were body weight, duration of work, and chromium concentration. After getting all variables above, breathing rate and intake non-carcinogen per respondent can be calculated. Then, the effective dose of foods rich in glutathione and costs of foods will be obtained. RESULTS: The results of this research indicated that the highest cost of foods intake containing glutathione was 5948 idr of broccoli per week and the lowest cost of foods intake was 535 idr of avocado per week. CONCLUSION: Intake of foods containing glutathione (avocado, broccoli, carrot, tomato, and grape) was expected to increase detoxification of chromium. Each individual had a different amount of cost. This depends on the effective dose, chromium concentration, weight, and duration of work per respondent.