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Acute toxicity and morphological modifications of dichlorvos to Eisenia foetida were assessed by directcontact test via a filter paper. The 24 and 48 h LC50 were 70 and 50 ppm, respectively. MorphologicalObservations demonstrated body ruptures and bloody injuries. The pattern of pesticide usage, management,their health effects on farmers, and farmers perception towards pesticides was also studied. Data werecollected viaa structured questionnaire, formal and informal interviews, and group discussions. The resultspoint out that pesticides are readily available and extensively applied in crop cultivation. The primarypurpose of presenting pesticides in the crop fields was to forestall and control pests and diseases.Organophosphates were the most generally utilized pesticides by farmers. Farmer’s reported manualapplication as the method of choice for pesticide application, and most of the farmers confirmed that noessential safety measures and precautions were embraced when pesticides were applied. Education waswitnessed to influence the farmer’s approach towards taking appropriate protective measures; however,there was no association between farmer’sage and pesticide health effects. The level of education and analphabetic contributed significantly to poor awareness of pesticide use. The configuration of pesticide usesamong farmers, therefore, needs improvement.

Malathion, a pesticide used to control pests in crops, vegetables, fruits, and livestock. Its widespread and indiscriminate usage has ensued in different ecological issues, thus, it's vital to remediate this insecticide. Malathion degrading bacterium Bacillus sp. AGM5, isolated from pesticide contaminated agricultural field was cultured in presence of different malathion concentrations under aerobic and energy restrictive conditions and was found effective at malathion degradation. Recovered malathion was extracted based on QuEChERS approach and then analyzed by UHPLC. About 39.5% of malathion biodegradation was observed at 300 µlL

Malathion is widely used as an agricultural insecticide, but its toxic nature makes it a serious environmental contaminant. To screen indigenous bacteria for malathion degradation, a strain MAGK3 capable of utilizing malathion as its sole carbon and energy source was isolated from Pennisetum glaucum agricultural soil. Based on morphological and biochemical characteristics and 16S rDNA sequence analysis, strain MAGK3 was identified as Micrococcus aloeverae. The strain was cultured in the presence of malathion under aerobic and energy-restricting conditions, and it grew well in MSM containing malathion (1000 µl/L), showing the highest specific growth rate at 500 µl/L

Pesticides currently play a significant role in enhancing agricultural production and offer economic assistance to our farmers. However, their indiscriminate and injudicious application has caused environmental problems and public health concerns. Chlorpyrifos, a pesticide of organophosphate category is used globally as an insecticide, acaricide, and termiticide in households, public health, and agriculture against pests of a wide range. The extensive application of chlorpyrifos has caused contamination of various ecosystems like soil, sediments, water, air and also leads to the disruption of biogeochemical cycles. Moreover, chlorpyrifos residues have been detected in sediments, soil, water, vegetables, foodstuff and even in human fluids. It has been confirmed that exposure to chlorpyrifos has created health complications due to the inhibition of choline esterase enzyme, which leads to neurotoxicity, immunological and psychological effects in humans plus to the natural ecosystem. Due to the higher toxicity of chlorpyrifos, research is conducted globally to design and develop effective and efficient approaches for the elimination of chlorpyrifos and its associated compounds from environmental settings. At present different techniques are available for detoxification of such pesticides, but the microbial degradation of chlorpyrifos especially by bacteria has proven to be highly efficient, economical and environmental friendly. Thus, this paper aims to provide an outline of research events on this issue and summarize the evidences of chlorpyrifos pollution, discuss the analytical summary of latest research results on bacterial degradation of chlorpyrifos and possible degradation pathways along with effects on its degradation by different environmental parameters.

The aim of present study is to isolate and characterize the indigenous bacterial isolates from textile industry effluents and sludge samples and investigate their decolorization ability, along with the influence of various process parameters on decolorization. Nine different bacterial strains were isolated from textile unit site in which one isolate (TS2O), having greater ability towards color removal was identified as Planococcus sp. by 16S rDNA sequencing. Optimization of decolorization process parameters was performed using Taguchi method in which five factors at two levels have been applied in L-8 orthogonal array. Maximum color removal rate (45%) has been obtained by 2% nitrogen, 1% carbon, 10% effluent, at pH 8 and 25 °C. The decolorization rate has been improved to 55% by adding peptone (0.5%w/v) as best nitrogen source and further up to 60% with dextrose (0.5%w/v) as best carbon source. A significant improvement up to 78% decolorization was observed during process parameter optimization with this statistical approach. Hence, this method validates its usefulness to treat various industrial wastewaters economically.

Heavy metal and pesticide pollution have become an inevitable part of the modern industrialized environment that find their way into all ecosystems. Because of their persistent nature, recalcitrance, high toxicity and biological enrichment, metal and pesticide pollution has threatened the stability of the environment as well as the health of living beings. Due to the environmental persistence of heavy metals and pesticides, they get accumulated in the environs and consequently lead to food chain contamination. Therefore, remediation of heavy metals and pesticide contaminations needs to be addressed as a high priority. Various physico-chemical approaches have been employed for this purpose, but they have significant drawbacks such as high expenses, high labor, alteration in soil properties, disruption of native soil microflora and generation of toxic by-products. Researchers worldwide are focusing on bioremediation strategies to overcome this multifaceted problem, i.e., the removal, immobilization and detoxification of pesticides and heavy metals, in the most efficient and cost-effective ways. For a period of millions of evolutionary years, microorganisms have become resistant to intoxicants and have developed the capability to remediate heavy metal ions and pesticides, and as a result, they have helped in the restoration of the natural state of degraded environs with long term environmental benefits. Keeping in view the environmental and health concerns imposed by heavy metals and pesticides in our society, we aimed to present a generalized picture of the bioremediation capacity of microorganisms. We explore the use of bacteria, fungi, algae and genetically engineered microbes for the remediation of both metals and pesticides. This review summarizes the major detoxification pathways and bioremediation technologies; in addition to that, a brief account is given of molecular approaches such as systemic biology, gene editing and omics that have enhanced the bioremediation process and widened its microbiological techniques toward the remediation of heavy metals and pesticides.

To sustain the quantity and quantity to fulfill the increased food demand of the rapidly growing population, agricultural industry plays an important role in the survival of nations. The agricultural industry has undertaken numerous scientific innovations to make it highly efficient and sustainable. However, if such improvements have resulted in enhanced yields, they have concurrently also triggered the degradation of the environment. One such problem is posed by organophosphate pesticides that are being extensively utilized in agricultural practices and other activities because of their greater efficiency and lesser environmental persistence. But utilization of these pesticides poses a threat to the environment because of their toxic nature and persistence in the food chain. Residues of these pesticides usually get build up in the upper surface of the soil and ultimately find their way into the food products. Once consumed by the humans and other living organisms, these pesticides affect not only them but also the population of various groups of soil microbes and their biochemical activities in the soil. Bacteria, fungi, and plants have demonstrated the capability to degrade these pesticides from the environment. Hence, bioremediation has been considered as an attractive, potentially appropriate, efficient, cost-effective, and an eco-friendly method for decontamination of pesticide-contaminated sites. Therefore, in this chapter, an attempt has been made to provide an overview of various types of pesticides, followed by analyzing the impacts of organophosphates, their toxicological mechanism, pollution status, and biodegradation in the environment.

Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture, household, and public health sectors and, hence, are extensively distributed throughout most ecosystems. Currently, organophosphate pesticides are the most commercially favored group of pesticides, with large application areas all over the world. Depending on their fate, these organophosphorus compounds may become bioavailable for microbial degradation. Environmental microbes, such as Aspergillus, Pseudomonas, Chlorella, and Arthrobacter, are capable of coupling a variety of physical and biochemical mechanisms for the degradation of organophosphate pesticides, including adsorption, hydrolysis of P–O alkyl and aryl bonds, photodegradation, and enzymatic mineralization. Enzymes, such as esterase, diisopropyl fluorophosphatase, phosphotriesterase, somanase, parathion hydrolase, and paraoxonase, have been isolated from microbes to study and understand the catabolic pathways involved in the biotransformation of these xenobiotic compounds. This review highlights various aspects of biodegradation of organophosphate pesticides along with biological and molecular characterization of some organophosphate pesticide-degrading bacteria.

Microbial activities are affected by a myriad of factors with end points involved in nutrient cycling and carbon sequestration issues. Because of their prominent role in the global carbon balance and their possible role in carbon sequestration, soil microbes are very important organisms in relation to global climate changes. This review focuses mainly on the responses of soil microbes to climate changes and subsequent effects on soil carbon dynamics. An overview table regarding extracellular enzyme activities (EAA) with all relevant literature data summarizes the effects of different ecosystems under various experimental treatments on EAA. Increasing temperature, altered soil moisture regimes, and elevated carbon dioxide significantly affect directly or indirectly soil microbial activities. High temperature regimes can increase the microbial activities which can provide positive feedback to climate change, whereas lower moisture condition in pedosystem can negate the increase, although the interactive effects still remain unanswered. Shifts in soil microbial community in response to climate change have been determined by gene probing, phospholipid fatty acid analysis (PLFA), terminal restriction length polymorphism (TRFLP), and denaturing gradient gel electrophoresis (DGGE), but in a recent investigations, omic technological interventions have enabled determination of the shift in soil microbe community at a taxa level, which can provide very important inputs for modeling C sequestration process. The intricacy and diversity of the soil microbial population and how it responds to climate change are big challenges, but new molecular and stable isotope probing tools are being developed for linking fluctuations in microbial diversity to ecosystem function.

DNA gyrase, a typical type II topoisomerase that can introduce negative supercoils in DNA, is essential for replication and transcription in prokaryotes. The apicomplexan parasite Plasmodium falciparum contains the genes for both gyrase A and gyrase B in its genome. Due to the large sizes of both proteins and the unusual codon usage of the highly AT-rich P. falciparum gyrA (Pf gyrA ) and Pf gyrB genes, it has so far been impossible to characterize these proteins, which could be excellent drug targets. Here, we report the cloning, expression, and functional characterization of full-length PfGyrB and functional domains of PfGyrA. Unlike Escherichia coli GyrB, PfGyrB shows strong intrinsic ATPase activity and follows a linear pattern of ATP hydrolysis characteristic of dimer formation in the absence of ATP analogues. These unique features have not been reported for any known gyrase so far. The Pf gyrB gene complemented the E. coli gyrase temperature-sensitive strain, and, together with the N-terminal domain of PfGyrA, it showed typical DNA cleavage activity. Furthermore, PfGyrA contains a unique leucine heptad repeat that might be responsible for dimerization. These results confirm the presence of DNA gyrase in eukaryotes and confer great potential for drug development and organelle DNA replication in the deadliest human malarial parasite, P. falciparum .