Defluoridation of water using autochthonous bacterial isolates

Area of Science:

• Environmental Microbiology
• Water Treatment Technologies
• Bioremediation

Background:

• Fluoride contamination in drinking water causes significant health issues like dental and skeletal fluorosis.
• Effective water defluoridation is crucial, especially in water-scarce regions like parts of India.
• Bioremediation using fluoride-resistant bacteria presents a promising approach for water defluoridation.

Purpose of the Study:

• To isolate and identify fluoride-resistant bacteria from contaminated groundwater and soil.
• To evaluate the defluoridation potential of these bacterial isolates.
• To optimize defluoridation conditions for the most effective bacterial strain using real water samples.

Main Methods:

• Isolation and screening of fluoride-resistant bacteria from environmental samples.
• Identification of highly resistant isolates using biochemical and possibly molecular methods.
• Assessing fluoride removal efficiency in nutrient broth and real water samples.
• Optimization of defluoridation parameters (temperature, pH, inoculum ratio) using Taguchi design of experiments.

Main Results:

• Three highly fluoride-resistant bacterial isolates (Aeromonas sp., Brevibacterium sp., Paenibacillus sp.) were identified.
• Paenibacillus sp. demonstrated the highest fluoride removal capacity (76.7% in broth).
• Optimized conditions (40 °C, pH 8, 2:1 inoculum:water ratio) yielded 73.3% defluoridation in real water samples.

Conclusions:

• Fluoride-resistant bacteria, particularly Paenibacillus sp., show significant potential for biological water defluoridation.
• The defluoridation capacity of Paenibacillus sp. in real water samples is the highest reported to date.
• Further research into commercial application of this bacterial strain for water treatment is warranted.