Effect of Organic Amendments on the Oxygen Uptake of Pseudomonas putida—PAPs-1 in Chromium-Contaminated Pond Ash

Abstract

In this study a Cr (VI) resistant bacterium Pseudomonas putida was isolated from pond ash and its oxygen consumption potential at different concentrations of Cr (VI) viz., 0, 100 and 200 mg kg⁻¹ was studied using Electrolytic Respirometry. Oxygen consumption by the bacterium was noticed up to 200 mg kg⁻¹ Cr (VI) concentration. To the pond ash (inoculated with and without Pseudomonas) 200 mg kg⁻¹ Cr (VI) was added and incorporated with different organic amendments such as farmyard manure (FYM), coir pith, paddy straw and press mud and the cumulative oxygen consumption was studied. The cumulative oxygen consumption by the bacterium was higher when the pond ash was incorporated with organic amendments. The highest oxygen consumption of 205 mg l⁻¹ was observed when press mud was used, which was followed by FYM (198 mg l^{− 1} ). Furthermore, the enrichment with press mud increased the nutrient content of N (57.28 mg kg⁻¹ ), P (5.5 mg kg⁻¹ ) and K (42.7 mg kg⁻¹ ) of the pond ash. The maximum dehydrogenase enzyme activity of 0.63 μ g TPF formed g⁻¹ sample h⁻¹ was measured when the pond ash was inoculated with Pseudomonas and enriched with press mud. The results also indicated that maximum reduction of Cr (VI) (42.5%) was observed when Pseudomonas and press mud were used. This study evaluated the possibilities of toxicity reduction and nutrient enrichment of the ash pond using a Cr (VI) resistant bacterium and organic amendments.

Keywords:

• Ash pond
• bioremediation
• chromium reduction
• nutrient enrichment.

We thank the Standing Scientific Research Committee (SSRC), Ministry of Coal, Government of India, New Delhi, India for the financial support through Central Mine Planning and Design Institute (CMPDIL), Coal India Limited, Ranchi, India under the S&T project “Pond Ash Reclamation and Possibilities of Industrial Waste for Revegetation and Developing Green Cover” (Project Code No: EE/18/98) and Centre for Applied Research and Development (CARD), NLC Ltd., Neyveli, India for providing laboratory facilities to undertake this study.

Notes

^*Values are mean of 3 replications.