Arun S. Kharat

Prof. Arun S. Kharat

Jawaharlal Nehru University,Delhi
orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 June 2017 in African Journal of Microbiology Research
Verified
Journal Article
Open access
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GSG. Parte Satish
G. Parte Satish
DAD. Mohekar Ashokrao
D. Mohekar Ashokrao
AKArun S. Kharat
Arun S. Kharat
Excessive use of pesticides has been known to be hazardous to the environment, affect soil fertility as well may impart toxicity in living beings. Presently there have been physical, chemical, biological and enzymatic approaches implicated to reduce pesticides. Although aimed to eradicate, physical and chemical methods are inefficient. Curiously, microbial pesticide remediation has been cost effective and thermodynamically more affordable, which may use any physical mater soiled with pesticide. Under favourable conditions microbes have been reported to use pesticides as source of carbon, sulphur and electron donor. Microbes; bacteria, actinomycetes and fungi have been found to help remove or detoxify chlorinated pesticides; polychlorinated diphenyl, polycyclic aromatic hydrocarbons, organophosphorus. Major bacterial genera includes; Bacillus, Pseudomonas, Flavobacterium, Moraxalla, Acinetobacter, Arthrobacter, Paracoccus, Aerobacter, Alkaligens, Burkholderia and Sphingomonas. Fungi with pesticide degradation potential includes;Fusarium, Aspergilus niger, Penicillium, Lentinulaedodes, Lecanicillium, Oxysporum. Among the Actinomycetes theStreptomycetes have been found to successfully detoxify pesticides. Persistent organic pollutants in the form of pesticides have also been reported to be taken care by the microbial enzymes viz-a-viz; dehydrogenase, ligninase, oxygenase, peroxidises, phosphotriesterase, hydrolases, dehalogenase, laccase and organophosphorus acid anhydrolase. Microbial strategies and tools; enzymes and genes involved in pesticide catabolism are reviewed. Key words: Chlorinated pesticides, organophosphors pesticides, bacteria, fungi, enzyme.

21 February 2024 in Critical Reviews in Microbiology
Verified
Journal Article
Closed access
RARupesh Aggarwal
Rupesh Aggarwal
PMPooja Mahajan
Pooja Mahajan
SPSameeksha Pandiya
Sameeksha Pandiya
ABAayushi Bajaj
Aayushi Bajaj
SVShailendra Kumar Verma
Shailendra Kumar Verma
AJAtul Kumar Johri
Atul Kumar Johri
Healthy state is priority in today's world which can be achieved using effective medicines. But due to overuse and misuse of antibiotics, a menace of resistance has increased in pathogenic microbes. World Health Organization (WHO) has announced ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) as the top priority pathogens as these have developed resistance against certain antibiotics. To combat such a global issue, it is utmost important to identify novel therapeutic strategies/agents as an alternate to such antibiotics. To name certain antibiotic adjuvants including: inhibitors of beta-lactamase, efflux pumps and permeabilizers for outer membrane can potentially solve the antibiotic resistance problems. In this regard, inhibitors of lytic domain of lytic transglycosylases provide a novel way to not only act as an alternate to antibiotics but also capable of restoring the efficiency of previously resistant antibiotics. Further, use of bacteriophages is another promising strategy to deal with antibiotic resistant pathogens. Taking in consideration the alternatives of antibiotics, a green synthesis nanoparticle-based therapy exemplifies a good option to combat microbial resistance. As horizontal gene transfer (HGT) in bacteria facilitates the evolution of new resistance strains, therefore identifying the mechanism of resistance and development of inhibitors against it can be a novel approach to combat such problems. In our perspective, host-directed therapy (HDT) represents another promising strategy in combating antimicrobial resistance (AMR). This approach involves targeting specific factors within host cells that pathogens rely on for their survival, either through replication or persistence. As many new drugs are under clinical trials it is advisable that more clinical data and antimicrobial stewardship programs should be conducted to fully assess the clinical efficacy and safety of new therapeutic agents.

1 January 2022 in Oxidative Medicine and Cellular Longevity
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Journal Article
Open access
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RPRohini Pungle
Rohini Pungle
SNShivraj Hariram Nile
Shivraj Hariram Nile
NMNilesh Makwana
Nilesh Makwana
RSRagini Singh
Ragini Singh
RSRana P. Singh
Rana P. Singh
AKArun S. Kharat
Arun S. Kharat
In this study, we report the green synthesis of silver nanoparticles (AgNPs) using the aqueous leaf extract of Tridax procumbens (TNP), which acts as the source of the reducing and capping agent. The distinctive absorption at 370 nm suggested synthesis of TNPs, which was confirmed by TEM, with a size in the range of 11.1 nm to 45.4 nm and a spherical shape, having a face‐centered cubic structure, analyzed by XRD, and a Zeta potential of ‐20.7 mV, which indicated a moderate stability of TNP. The FTIR analysis revealed the presence of amines and hydroxyl groups with fluoro compounds over the TNPs. The HRLC‐MS analysis of TNPs suggested the presence of a major capping agent such as fosinopril and reducing agents such as peptides (Gln Gly Ala, Ser Pro Asn, and Leu Met), terpenoids (lupanyl acid, tiamulin), polyphenol (peucenin), and alkaloids (8 ′,10 ′‐dihydroxydihydroergotamine, carteolol). The synthesized silver nanoparticles exhibited antimicrobial activity against multidrug‐resistant (MDR) clinical isolates (Escherichia coli, Shigella spp., Aeromonas spp., Pseudomonas aeruginosa, and Candida tropicalis) and had anticancer activity against A459 (IC50 42.70 μg/ml). The extraction of partially purified aqueous leaf extracts by silica gel column chromatography followed by HPLC to synthesize silver nanoparticles (TNP11) and analyzed by HRLC‐MS suggested that dipeptides were involved in the reduction of Ag+ to Ag0. Overall, the results showed that the green silver nanoparticles of T. procumbens could be safe, as they are endowed with potential antimicrobial activity against MDR clinical isolates and human lung carcinoma cells.

29 February 2024 in International Journal of Antimicrobial Agents
Verified
Journal Article
Closed access
AKArun S. Kharat
Arun S. Kharat
NMNILESH MAKWANA
NILESH MAKWANA
MNMahfouz Nasser
Mahfouz Nasser
SGSamarpita Gayen
Samarpita Gayen
BYBipin Yadav
Bipin Yadav
CMCorinne Mercier
Corinne Mercier

21 October 2020 in Microorganisms
Verified
Journal Article
Open access
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MNMahfouz Nasser
Mahfouz Nasser
SPSnehal Palwe
Snehal Palwe
RBRam Naresh Bharagava
Ram Naresh Bharagava
MFMarc G.J. Feuilloley
Marc G.J. Feuilloley
AKArun S. Kharat
Arun S. Kharat
The production of diverse and extended spectrum β-lactamases among Escherichia coli and ESKAPE pathogens is a growing threat to clinicians and public health. We aim to provide a comprehensive analysis of evolving trends of antimicrobial resistance and β-lactamases among E. coli and ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acine to bacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) in the Arabian region. A systematic review was conducted in Medline PubMed on papers published between January 2000 and February 2020 on countries in the Arab region showing different antibiotic resistance among E. coli and ESKAPE pathogens. A total of n = 119,144 clinical isolates were evaluated for antimicrobial resistance in 19 Arab countries. Among these clinical isolates, 74,039 belonged to E. coli and ESKAPE pathogen. Distribution of antibiotic resistance among E. coli and ESKAPE pathogens indicated that E. coli (n = 32,038) was the predominant pathogen followed by K. pneumoniae (n = 17,128), P. aeruginosa (n = 11,074), methicillin-resistant S. aureus (MRSA, n = 4370), A. baumannii (n = 3485) and Enterobacter spp. (n = 1574). There were no reports demonstrating Enterococcus faecium producing β-lactamase. Analyses revealed 19 out of 22 countries reported occurrence of ESBL (Extended-Spectrum β-Lactamase) producing E. coli and ESKAPE pathogens. The present study showed significantly increased resistance rates to various antimicrobial agents over the last 20 years; for instance, cephalosporin resistance increased from 37 to 89.5%, fluoroquinolones from 46.8 to 70.3%, aminoglycosides from 40.2 to 64.4%, mono-bactams from 30.6 to 73.6% and carbapenems from 30.5 to 64.4%. An average of 36.9% of the total isolates were reported to have ESBL phenotype during 2000 to 2020. Molecular analyses showed that among ESBLs and Class A and Class D β-lactamases, blaCTX-M and blaOXA have higher prevalence rates of 57% and 52.7%, respectively. Among Class B β-lactamases, few incidences of blaVIM 27.7% and blaNDM 26.3% were encountered in the Arab region. Conclusion: This review highlights a significant increase in resistance to various classes of antibiotics, including cephalosporins, β-lactam and β-lactamase inhibitor combinations, carbapenems, aminoglycosides and quinolones among E. coli and ESKAPE pathogens in the Arab region.

1 September 2020 in Journal of Global Antimicrobial Resistance
Verified
Journal Article
Open access
MNMahfouz Nasser
Mahfouz Nasser
SGSamarpita Gayen
Samarpita Gayen
AKArun S. Kharat
Arun S. Kharat
Several studies in the Arab region have recognized the rate of nosocomial infections caused by Pseudomonas aeruginosa which produce β-lactamase and identified their emergence and prevalence in the region. This article seeks to review molecular studies on these β-lactamase producing Pseudomonas aeruginosa during the period 2010 to 2018 in several countries of the Arab region in order to analyze the trend of rising prevalence of disease causing drug resistant Pseudomonas aeruginosa in the Arab region. The data available from selected clinical studies during the period 2010 to 2018 on β-lactamase producing P. aeruginosa in the Arab region obtained from reliable scientific databases was analyzed and evaluated. Significant changes have been found in resistance of Pseudomonas aeruginosa towards certain antibiotics of the β-lactam class. There is an increasing trend in the occurrence of resistance genes in β-lactamase producing P. aeruginosa. This review shows that there is increasing prevalence of β-lactamase producing P. aeruginosa in some countries in the Arab region. This is a major cause of concern as this implies that more and more instances of multidrug resistance are emerging in this area. This leads to an overall negative impact on the health concerns and amounts to increasing difficulty in combating disease. It is recommended that awareness about antibiotic use and abuse be made a priority and measures of curbing unchecked use of prescription antibiotics be put into place. Effective screening methods to detect cases of resistance at their onset may be developed.