No abstract

Background: Extended spectrum β-lactamases (ESBL) producing E. coli co-producing other β-lactamases and exhibiting co-resistance to different antibiotic classes continue to emerge as a threat to clinical field. This study aimed to analyze the co-production of New Delhi metallo-β-lactamase-1 (blaNDM-1) in ESBL producing plasmid-bearing clinical isolates collected from two tertiary care centres in Kerala, South India, and to understand their genetic relatedness. Methods: Antibiotic resistance phenotypes of 44 clinical isolates were determined by disc-diffusion method. Plasmidbearing isolates, detected by the alkaline-lysis method, which also tested positive for ESBL production, were screened for the presence of blaNDM-1 by polymerase chain reaction. Plasmid, random amplified polymorphic DNA profiles and blaNDM-1 sequence-based phylogenetic tree were analyzed to understand the genotypic similarities among the isolates. Results: Beta-lactam antibiotics, quinolones, cephalosporins, used in this study, and AZM were found to be ineffective against the isolates as significantly high number of isolates were resistant to these antibiotics (P < 0.01). Plasmid bearing isolates constituted 57% (n = 25), all of which were found to be ESBL producers. blaNDM-1 amplicons were noticed in four (16%) isolates and these DNA sequences showed homology between them and with similar sequences reported from other countries like Japan and Korea. Plasmid and RAPD profiles demonstrated that most of the isolates, including those harbouring blaNDM-1 shared genetic similarities as well as an apparent geographical distinctiveness. Conclusion: The predominance of ESBL production and the occurrence of blaNDM-1 in plasmid-bearing isolates observed in our study corroborate the worldwide drug-resistance * Corresponding author.N. Narayanan et al. 126scenario. This study thus warrants the need for constant surveillance in the face of sparse information available in Kerala State on the emerging drug resistance in clinical bacteria.

<p class="Default">Zingiberaceae family members are well known for their ethnobotanical diversity and medicinal importance.  This study aimed to evaluate total phenolic content, antioxidant and antiproliferative capacity of five different organic solvent extracts prepared from the rhizomes of <em>Curcuma mutabilis</em> (CM)<em>, Curcuma haritha </em>(CH)<em>, Curcuma neilgherrensis</em> (CN) and<em> Zingiber anamalayanum</em> (ZA), four hitherto unexplored Zingiberaceae species.  Folin-<span class="tgc">Ciocalteu method and </span>DPPH radical scavenging assay were used to determine respectively the total phenolic content and<span class="tgc"> antioxidant </span>capacity.<span class="tgc">  </span>The antiproliferative activity of the extracts were tested against four human cancer cell lines –  K562,  REH, Nalm6 and MCF7 to ascertain the IC₅₀ values.  Based on total phenolic content, extracts were classified into high-H (&gt; 150 mg GAE/g), medium-M (50-150 mg GAE/g) and low-L (&lt; 50 mg GAE/g) categories.  Likewise, percentages of DPPH scavenging activity of extracts were also grouped into high-H (&gt; 50%), medium-M (25 – 50%) and low-L (&lt; 25%) categories.  Ten of the twenty extracts exhibited strong cytotoxicity with an IC₅₀value less than 30 μg/mL.  To our knowledge, this is the first report on quantitative assessment of total phenolics, antioxidant and antiproliferative potential of organic solvent extracts of rhizomes from the above mentioned plants.</p>