Microbial Ecology of Denitrification Process and Its Application in Wastewater: Treatment, Challenges and Opportunities
Asma Shakeel
Division of Soil Science & Agric chemistry, FoA Wadura, SKUAST-K, India.
Inayat M.Khan
Division of Soil Science & Agric chemistry, FoA Wadura, SKUAST-K, India.
GM IMRAN
Professor jayashankar Telangana state agricultural university Hyderabad,TS, India.
S. Anandha Krishnaveni *
Anbil Dharmalingam Agricultural College and Research Institute, Trichy - 620 027, Tamil Nadu, India.
Malathi G
Horticultural Research Station Yercaud Salem Tamil Nadu, India.
T. Sivasankari Devi
Agricultural Microbiology, Tamil Nadu Rice Research Institute, Aduthurai, Tamil Nadu, Pin code: 612 101, India.
T.M. Sathees Kannan
P.G. & Research Department of Botany, A.V.C. College (Autonomous), Mannampandal, Mayiladuthurai - 609 305, Tamil Nadu, India.
Syed Andleeb
Division of Soil Science & Agric chemistry, FoA Wadura, SKUAST-K, India.
Priya Subramanian Kalaimani
Department of Food Biotechnology, NIFTEM-Thanjavur, Thanjavur-613005, Tamil Nadu, India.
A. Krishnaveni
HC&RI, Jeenur, Paiyur, Krishnagiri District PIN-635112, Tamil Nadu India.
*Author to whom correspondence should be addressed.
Abstract
Denitrification is a crucial microbial process in the nitrogen cycle, transforming nitrate (NO₃⁻) into nitrogen gas (N₂), thereby mitigating nitrogen pollution in aquatic ecosystems. This microbial activity plays a vital role in wastewater treatment by removing excess nitrogen, which contributes to eutrophication and water contamination. The denitrification process involves various microbial communities, including bacteria such as Pseudomonas, Paracoccus, and Bacillus, which operate under anoxic conditions to achieve nitrogen reduction, an optimizing denitrification in wastewater treatment presents several challenges, such as maintaining ideal environmental conditions (e.g., carbon availability, oxygen levels, pH) and overcoming issues related to incomplete denitrification, which can lead to the production of harmful intermediates like nitrous oxide (N₂O). Despite these hurdles, recent advancements in microbial ecology, such as the use of biofilms, bioreactors, and genetic engineering, offer promising opportunities to enhance denitrification efficiency. This review explores the microbial ecology of the denitrification process, its application in wastewater treatment, and the challenges and opportunities associated with its practical implementation in reducing nitrogen pollution.
Keywords: Denitrification, microbial ecology, wastewater, biofilms, wastewater influent, nitrifiers, phylogenetics, autoradiography, PCR (Polymerase chain reaction)