Biological Degradation of Metribuzin and Profenofos by some Efficient Bacterial Isolates

Abstract

The soil sample was collected from the paddy field of Sriperumbudur, Tamilnadu which is having a history of repeated pesticide applications. The isolation of efficient pesticide degrading bacteria was identified as Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis. The growth of the three pesticide degrading isolates was assessed in Minimal salt broth containing 25 ppm of pesticides. Two popularly used pesticides Metribuzin and Profenofos were selected for this study. Among the three bacterial isolates, the bacteria Bacillus subtilis utilized the pesticides effectively and showed maximum growth. The growth of the three pesticides degrading isolates Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis was assessed in Minimal salt broth containing 25 ppm of pesticides at different temperature levels (25 °C, 30 °C, 35 °C, 40 °C, 45 °C, 50 °C & 55 °C) and pH levels (pH 4, pH 5, pH 6, pH 7 & pH 8) and carbon sources (Lactose, Dextrose, Fructose, Mannose & Galactose) and nitrogen sources Peptone, Yeast extract, Beef extract, Malt extract and Casein respectively. The maximum growth rate of bacteria was recorded at 35 °C and pH 6. The maximum growth of bacteria was in the presence of Dextrose followed by Fructose, Galactose and Mannose. The least growth was recorded in Lactose broth culture. The maximum growth of bacteria was in the presence of Malt extract followed by Peptone, Yeast extract and Casein. The least growth was recorded in Beef extract broth culture. The bacterial isolates showed maximum growth in the Minimal salt broth containing Profenofos followed by Metribuzin.

Biodegradation kinetics of diuron by Pseudomonas aeruginosa FN and optimization of biodegradation using response surface methodology

“…According to literature there are two main mechanisms involved in the partial degradation of diuron to 3,4-DCA, N-demethylation and hydrolysis of the amide bond by enzyme amidase (Giacomazzi and Cochet, 2004). The pollution of water and soil by diuron has become a more serious problem due to the formation of 3,4-DCA which can accumulated in the soil and leaching to the groundwater (Tixier et al, 2002;Sørensen et al, 2003;Giacomazzi and Cochet, 2004) There are various pesticide removal studies such as photocatalytic degradation, oxidation, ozonation, photo-Fenton reactions and biodegradation by various microorganisms (Tamilselvan et al, 2014;Ayed et al, 2017;Miller et al, 2017). The biodegradation process is one promising treatment method to remove pollutants from contaminated sites by microorganisms and it is effective, minimally hazardous, economical, versatile and environment-friendly process (Finley et al, 2010).…”

“…There are various pesticide removal studies such as photocatalytic degradation, oxidation, ozonation, photo‐Fenton reactions and biodegradation by various microorganisms (Tamilselvan et al , 2014; Ayed et al , 2017; Miller et al , 2017). The biodegradation process is one promising treatment method to remove pollutants from contaminated sites by microorganisms and it is effective, minimally hazardous, economical, versatile and environment‐friendly process (Finley et al , 2010).…”

Characterization of Profenofos Degrading Bacteria

“…Namun, di antara ketiga genus tersebut, publikasi ilmiah tentang biodegradasi pestisida dan hidrokarbon aromatik oleh Pseudomonas jauh lebih banyak. Mayoritas rujukan ilmiah juga menunjukkan bahwa Pseudomonas memiliki kemampuan biodegradasi yang lebih baik dengan kisaran substrat yang juga lebih luas termasuk organochlorine pesticides (Singh dan Walker 2006;Tamilselvan et al 2014;Wald et al 2015;Satish et al 2017). Studi metabolomik mengindikasikan kemampuan Pseudomonas tersebut terkait dengan ragam biodegradation pathway yang dimilikinya (Pailan dan Saha 2015).…”