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Zingiberaceae family of plants are ethnomedicinally well known. One of the less‐studied endemic species from this family, Curcuma neilgherrensis, and its leaves have been used as a folklore medicine by tribes of Western Ghats of India since ancient times. The aim of the study is to investigate in vitro antioxidant and antiproliferative potentials of organic solvent extracts prepared from C. neilgherrensis leaves as well as phytochemical profiling of the selected extract capable of apoptotic induction in cancer cells. In vitro antioxidant activity was evaluated by the estimation of total phenolics and flavanoid contents, DPPH, ABTS radical scavenging, and lipid peroxidation inhibition assays. Cytotoxic/antiproliferative potential was assessed employing human cancer cell lines (K562, HCT116, MDA‐MB‐231, and HL60) and normal lymphocyte cultures by MTT and trypan blue dye exclusion assays. Fluorescence microscopy, flow cytometry, DNA fragmentation, and caspase activity assays were utilized to study apoptosis induction by the extract in HCT116 cells. HR‐ESI‐MS/MS was used to identify chemical constituents present in the extract. C. neilgherrensis leaves extracts were found to contain varying amounts of total phenolics and flavanoid contents as well as antioxidant activity, with the methanolic extract (CNLM) displaying maximal activity. Higher antiproliferative potential was shown by the chloroform extract (CNLC) for a 48 h treatment period, against colorectal carcinoma HCT116 cells (IC50‐8.3 ± 0.8 μg/mL). CNLC treatment caused cytomorphological alternations, phosphatidylserine externalization, reduction in mitochondrial membrane potential, increase in intracellular ROS, sub‐G1 phase cell population, and DNA fragmentation, as well as caspase 3 and 9 activities, confirming apoptosis induction in HCT116 cells. Phytochemical profiling of the CNLC extract by HR‐ESI‐MS/MS enabled identification of bioactive compounds, previously reported with anticancer potential such as rutin, tamarixetin, embelin, ginkgolide B, traumatic acid, and rosmarinic acid. To our knowledge, this is the first report demonstrating in vitro antioxidant and antiproliferative potentials of C. neilgherrensis leaf extracts. The results presented reveal that C. neilgherrensis leaves are indeed a potent bioresource for chemotherapeutic candidate drugs for future use. [ABSTRACT FROM AUTHOR]

Background & objectives: β-lactamases play a predominant role in drug-resistance amongst Enterobacteriaceae. Presence of genes on transferable plasmids encoding these enzymes favours their dissemination across species and genera within and outside geographical boundaries. This study was aimed to understand the presence of β-lactamases and transferable plasmids in clinical isolates of Klebsiella spp. which can contribute to the spread of resistance determinants. Methods: A total of 41 clinical isolates of Klebsiella spp., collected from a tertiary care centre in Kerala, India, were checked for antibiotic sensitivity and the presence of plasmids. The ability to produce extended-spectrum β-lactamases (ESBLs) and metallo-β-lactamases (MBLs) was screened for and confirmed in 29 plasmid-harbouring isolates. blaNDM-1-specific primers were used for polymerase chain reaction amplification with plasmid DNA as template to determine episomal prevalence of this gene and its sequence-based phylogeny employing similar sequences from GenBank. Plasmid replicon typing was also carried out to determine the presence of transferable plasmids. Results: Our results showed a high degree of multidrug-resistant (MDR) pathogens with ESBL production confirmed in 52 per cent, MBL in 31 per cent and co-production of both enzymes in seven per cent of the plasmid-bearing isolates. Plasmid DNA from 14 per cent of the isolates produced blaNDM-1-specific amplicons which showed sequence homology with those from bacteria of different genera and geographical areas. The predominant replicon type was found to be that of conjugative plasmids belonging to the incompatibility group - IncFIIK. Interpretation & conclusions: This study provides insight into the predominance of various β-lactamases and potent gene-disseminating agents in Klebsiella spp. and emphasizes the need for constant surveillance of these pathogens to determine appropriate treatment strategies. [ABSTRACT FROM AUTHOR]

Leaf extracts of C. vamana, endemic to Kerala state in India, were found to inhibit cell cycle progression in synchronous cultures of P. polycephalum in a concentration and phase-specific manner. Crude alkaloid extract (CAE) elicited maximum cell cycle delays in comparison to soxhletted chloroform, acetone and aqueous extracts. Total alkaloid content of CAE was found to be 64.9 mg/g. CAE showed lowest DPPH radical scavenging activity. Other extracts with higher free radical scavenging activity exhibited lesser cell cycle inhibiting potential. Upto 21% decrease in nuclear DNA was observed in CAE treated samples. However, genotoxicity as evidenced by comet assay was not observed. The extracts were also found to be non-toxic to human RBCs at the highest concentration tested (750 microg/mL). CAE treatment completely suppressed a 63 kDa polypeptide with a concomitant, but weak induction of a 60 kDa polypeptide suggesting that these may be cell cycle related. CAE was found to possess potent antiproliferative activity against PBLs. The study clearly demonstrates the cell cycle inhibitory activity of C. vamana leaf extracts, with CAE being the most potent of them.