BHU Institutional Repository :: Browsing by Author "Sharma, Swati"

Browsing by Author "Sharma, Swati"

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A review on biomacromolecular hydrogel classification and its applications
(Elsevier B.V., 2020) Sharma, Swati; Tiwari, Shachi
Biomacromolecular hydrogels are consist of 3D networks, which have a tendency to absorb large amount of water without dissolving in aqueous medium. Such inherent feature of the hydrogels facilitates the scientific research interest to a dominating path in extending their potential in various fields. In recent years, development of responsive hydrogels has been observed in various field. Self-healing property of the hydrogel attracts more attention in different areas because this property increases the lifespan of the polymeric material. By keeping all these views in mind, the present review focuses on the classification of biomacromolecular hydrogels, methods and its applications. The polymeric material exhibiting multi-responsive properties such as swelling, pH responsive, mechanically strong, self-healing, flexible plays vital role in different applications. In addition, this review summarizes the classification of hydrogels, based on their chemical and physical state along with the various applications. At the end, a brief outlook also presented the future aspects of the hydrogels. © 2020 Elsevier B.V.
Adaptations of carbapenem resistant Acinetobacter baumannii (CRAB) in the hospital environment causing sustained outbreak
(Microbiology Society, 2021) Sharma, Swati; Das, Arghya; Banerjee, Tuhina; Barman, Hiranmay; Yadav, Ghanshyam; Kumar, Ashok
Introduction. Carbapenem resistance in Acinetobacter baumannii (A. baumannii) is an emerging global threat. Gap statement. The adaptation strategies of A. baumannii for this emergence as a nosocomial pathogen has been less studied. Aim. This prospective study analysed a sustained outbreak of carbapenem resistant Acinetobacter baumannii (CRAB) in the intensive care unit (ICU) with reference to antimicrobial resistance and virulence in the colonizing and pathogenic isolates under carbapenem stress. Results. The CRAB isolates from initial and sustained outbreak were found harbouring multiple carbapenemase genes. These genes included blaOXA-23,blaIMP, blaVIM and blaNDM. From NICU environment three phenotypically carbapenem susceptible isolates were found carrying blaOXA-23, blaIMP, blaVIM genes. Prior imipenem therapy was one of the risk factors (P=0.0016). The outbreak was polyclonal. Under imipenem stress, outbreak isolates showed no loss of carbapenemase genes against stress free conditions (23.7±1.33 days). Biofilm formation increased with imipenem concentration, with outbreak isolates producing highest biomass. While the pathogens showed a slow growth rate on imipenem exposure, the colonisers grew rapidly (P <0.0001). Methods. Sustained outbreak of CRAB was identified in the ICU (July 2015 to December 2017). Risk factors for acquisition of CRAB was studied. A. baumannii isolates were also collected from the environments of ICU and neonatal ICU (NICU) and blood cultures of septic neonates. Isolates were characterized based on antimicrobial susceptibility, genetic profile, integrons carriage and clonality. Biofilm formation and growth kinetics were studied under varying carbapenem stress. Conclusion. Intense carbapenem exposure in the ICU facilitates persistence of CRAB by several adaptations causing sustained outbreaks. © 2021 The Authors.
Advances in Freeze Drying to Improve Efficiency and Maintain Quality of Dehydrated Fruit and Vegetable Products
(wiley, 2024) Sharma, Swati; Barman, Kalyan; Krishna, Hare; Chaurasia, Surya N.; Mujumdar, Arun S.
[No abstract available]
An umbrella review on ethnomedicinal, pharmacological and phytochemical profile of pointed gourd (Trichosanthes dioica Roxb.): A bioactive healthy vegetable of Indian subcontinent
(Elsevier Ltd, 2023) Sharma, Swati; Sinha, Ritika; Singh, Anil K.; Meena, Yogendra; Pongener, Alemwati; Sharma, Rohit; Behera, Tusar Kanti; Barman, Kalyan
Trichosanthes dioica Roxb. is a widely cultivated cucurbitaceous vegetable of tropical and sub-tropical regions. Its unripe fruits are consumed as vegetable. This review aims to present an umbrella overview of botany, ethnomedicinal uses, nutritional and phytochemical profile of T. dioica and compilation of research confirming many pharmacological and healing properties of its plant parts. Importantly, several reports from India and Bangladesh have confirmed its ethnomedicinal usage in many biomedical conditions. Bioactive compounds like triterpenes, polyphenols present in different parts of T. dioica make it a powerhouse of health, immunity and nutrition. Different parts of T. dioica including root, stem, leaf, fruit and seed exhibit wide range of therapeutic properties including antidiabetic, anti-tumour, antiulcer, antioxidant, anti-inflammatory, antidiarrheal, antihyperlipidemic, antipyretic, wound healing, laxative, antinociceptive and hepato-protective. Results signified that it may be useful to re-look to find possibilities for using its active metabolites in contemporary medicine and nutraceuticals. © 2023
Biological and postharvest interventions to manage the ethylene in fruit: a review
(Royal Society of Chemistry, 2023) Asrey, Ram; Sharma, Swati; Barman, Kalyan; Prajapati, Uma; Negi, Narender; Meena, Nirmal Kumar
Ethylene, the gaseous ripening hormone, notably influences the postharvest physiology of the fruit. The pronounced effect of ethylene on postharvest physiology ranges from beneficial to unacceptable, with substantial commercial repercussions. Climacteric fruit undergoes an ethylene burst with the onset of ripening, and this autocatalytic ethylene production leads to accelerated ripening and senescence of fruit. Thus, the fruit becomes soft, mealy, and prone to pathogen attack that ultimately leads to high postharvest losses during handling, storage, and marketing. The key to appropriate handling, storage, and marketing of fruit lies largely in the successful management of ethylene. Biological interventions such as gene silencing, gene editing and recently the gene modifications through CRISPR/Cas9 are widely accepted and being used to regulate ethylene in fruit. Nevertheless, postharvest interventions and use of novel molecules such as 1-MCP, polyamines, salicylic acid, and ozone have received commercial status for controlling ethylene action in fruit. Use of metal-based catalysts at low temperature has been considered as a safer approach. This review focuses on the history, biosynthesis, action mechanism and techniques employed for useful modulation of ethylene biosynthesis and action in harvested fruit. © 2023 The Author(s).
Chilling stress during postharvest storage of fruits and vegetables
(Springer Singapore, 2020) Sharma, Swati; Barman, Kalyan; Prasad, R.N.; Singh, J.
The commercial practice to extend postharvest life of freshly harvested horticultural commodities is storing them at low temperature. However, tropical and subtropical origin fruits and vegetables develop injury when stored at a very low temperature. The chilling stress causes damage to the susceptible fruits and vegetables during postharvest supply chain and is a major limitation for harnessing the beneficial effects of cold storage for extending their marketability. Different physiological and biochemical alterations cause cellular dysfunctions leading to the development of various symptoms in the produce affected by chilling stress. Several postharvest management strategies can be adopted to alleviate the harmful effects of chilling stress like modulating temperature and storage conditions, pre-storage physical or chemical treatments, etc. In this chapter, the response of commodities to chilling stress, its symptoms, alleviation strategies, and their mechanism have been discussed. © Springer Nature Singapore Pte Ltd. 2020. All rights reserved.
Comparative evaluation of colistin broth disc elution (CBDE) and broth microdilution (BMD) in clinical isolates of Pseudomonas aeruginosa with special reference to heteroresistance
(Indian Association of Medical Microbiologists, 2024) Banerjee, Tuhina; Adwityama, Adwityama; Sharma, Swati; Mishra, Kajal; Prusti, Prabha; Maitra, Upasona
Purpose: Antimicrobial resistance (AMR) in Pseudomonas aeruginosa has been ever-increasing. Among other reasons, colistin resistance might be attributed to limited routine testing by approved methods. Both broth microdilution (BMD) and colistin broth disc elution (CBDE) methods have been advocated, with limited data on the performance of these methods in the Indian settings. This prospective study was conducted to determine colistin resistance in P. aeruginosa, compare the BMD and CBDE methods with special reference to heteroresistance. Materials and methods: A total of 100 isolates of P. aeruginosa from admitted patients were included. Antimicrobial susceptibility testing was done against standard antibiotics by disc diffusion test. Minimum inhibitory concentration (MIC) against polymyxins was studied by BMD and CBDE (for colistin only). Heteroresistance to colistin was studied by population analysis profile (PAP). CBDE and BMD were compared by performance calculations. Discrepancy in results were analyzed based on heteroresistance. Results: Majority of the P. aeruginosa isolates were from pus samples (62, 62 %). Disc diffusion method revealed maximum susceptibility towards aztreonam (74, 74 %) followed by meropenem (68, 68 %) and piperacillin-tazobactam (65, 65 %). Polymyxin B resistance was seen in 6 % (6) while colistin resistance was seen in 9 % (9) isolates by BMD. CBDE revealed 8 % (8) resistance to colistin, having 97 % essential agreement and 95 % categorical agreement with BMD. Further, by PAP analysis, 9 isolates were resistant to colistin which included 9 resistant isolates by BMD. On discrepancy analysis, 1 isolate was found to be heteroresistant to colistin. No heteroresistance was seen in the isolates that were susceptible by all the methods. Conclusions: Heteroresistance to colistin in P. aeruginosa accounted for the discrepancy in results where CBDE method failed to detect heteroresistant isolate. As heteroresistance is a least studied phenotype, it's exact prevalence should be studied so that challenges in susceptibility testing could be addressed. © 2023 Indian Association of Medical Microbiologists
Developing a nontoxic and biocompatible polymeric self-assembly by using RAFT methodology for biomedical application
(Elsevier Ltd, 2019) Deepak; Sharma, Swati; Kumar, Ashok; Kumar, Rajesh; Nandy, Koushik; Srivastava, Arti; Tomar, Munendra Singh; Acharya, Arbind
The amphiphilic block copolymer poly(N-vinylpyrrolidone)-b-poly(N-vinylcarbazole) (PVP-b-PVK) was synthesized by reversible-deactivation radical polymerization (RDRP)using reversible addition-fragmentation chain transfer (RAFT) methodology by new chain transfer agent (CTA) i.e. benzyl piperidine dithiocarbamate (BPDC). The pseudo-first-order kinetics and linear evolution of the molar mass with N-vinylpyrrolidone (NVP) conversion were obtained with the molar mass dispersity (Ð) 1.30–1.41 in toluene. 1H NMR spectrum indicates the presence of chain-end functional groups on homopolymer and block copolymer. The above block copolymer get self-assembled and form micelles in the aqueous medium, the size of micelles is characterized by 1H NMR, transmission electron micrographs (TEM) and dynamic laser light scattering (DLS) analyses, and critical micelles concentration (CMC) was determined by UV–vis spectroscopy. Trypan blue exclusion and MTT assay were done to ensure the cytotoxic effect of PVP-b-PVK on different types of normal cells (thymocytes, splenocytes and macrophage), and no cytotoxic effect was shown by block copolymer on cells, while observed biocompatibility with cells was 200 mg/mL. Further, the beads of block copolymer releases (65%) highly water-soluble levofloxacin drug up to 8 h in a controlled manner at pH 7.4 (37 ± 0.2 °C), while loading of levofloxacin drug was 62% (w/w). © 2018 Elsevier Ltd
Development of a novel chitosan based biocompatible and self-healing hydrogel for controlled release of hydrophilic drug
(Elsevier B.V., 2018) Sharma, Swati; Kumar, Ashok; Deepak; Kumar, Rajesh; Rana, Nishant Kumar; Koch, Biplob
Smart polymeric hydrogels of chitosan and acryloyl-phenylalanine having potential of fast intrinsic shape memory properties (self-healing), non-toxic, biocompatible with moderate mechanical strength have been developed. The hydrogel has been formed by linking its network with flexible pendant side chains of chitosan and acryloyl-phenylalanine (exhibiting optimal balance of hydrophilic and hydrophobic moieties). The non-toxic and biocompatible behavior of the synthesized chitosan based hydrogel reveals its potential use towards the biomedical field. The side chain of hydrogel consists of amine and carboxylic acid groups and these moieties allow non-covalent interactions (H-bonding) across its interface. Thus, synthesized hydrogel shows very good self-healing property. Further, it has shown remarkable swelling (at different pH viz.- 2, 7, 9), cell viability (HEK-293 cells up to 200 μg/mL), cell proliferation, and controlled drug release and thus found multi-responsive. © 2018 Elsevier B.V.
Development of graft copolymer of carboxymethylcellulose and N-vinylcaprolactam towards strong antioxidant and antibacterial polymeric materials
(Elsevier B.V., 2018) Kumar, Ashok; Deepak; Sharma, Swati; Afgan, Shere; Kumar, Rajesh; Keshari, Anand Kumar; Srivastava, Ragini
The present paper reports graft copolymerization of N-vinylcaprolactam (NVCL) onto carboxymethylcellulose (CMC) using tert-butyl hydroperoxide (TBHP) initiator in N2 atmosphere. The grafting was found to be highest when concentrations of CMC, NVCL and TBHP were 6.25 × 10−2 g dm−3, 10 × 10−3 mol dm−3 and 20 × 10−5 mol dm−3 respectively. The graft copolymer (CMC-g-PNVCL-1) was characterized by FTIR, 1HNMR, SEM, AFM, XRD and TGA analysis. The antioxidant activity of the graft copolymer was found to be higher (3.81%) than CMC and slightly less (5.47%) than the standard one (butylated hydroxytoluene, BHT). The hydroxyl radical scavenging activity of graft copolymer was found to be slightly less (13.69%) than CMC and more (44.20%) than the BHT. The hydrogen peroxide scavenging activity of graft copolymer was observed to be less (20.42%) than CMC and 53.34% less than BHT. The superoxide scavenging activity of graft copolymer was greater than the both. Compared to CMC the graft copolymer has shown greater antibacterial activity against S. aureus, Proteus vulgaris and S. typhi bacteria and less against Klebsiella pneumonia and Salmonella typhimurium. © 2018 Elsevier B.V.
Dynamic imine bond based chitosan smart hydrogel with magnified mechanical strength for controlled drug delivery
(Elsevier B.V., 2020) Sharma, Swati; Jain, Pallavi; Tiwari, Shachi
Hydrogel finds an interesting candidate in the biomedical field due to their unique properties such as biocompatibility, biodegradability, soft as tissue etc. In the reported research article natural biopolymer i.e. chitosan based hydrogel was developed via condensation reaction with cuminaldehyde. Chitosan and cuminaldehyde were used for the gel formation by covalent bonding between free amino group and carbonyl group of chitosan & cuminaldehyde respectively. A series of hydrogel has been developed by taking different concentration of cuminaldehyde (6-10 mmol). Chemical structure of the synthesized hydrogel was further confirmed by FTIR. The surface morphology of the synthesized hydrogel was confirmed from the scanning electron microscopy (SEM). Prepared hydrogel was swelled very fast similar to the super-porous hydrogel along with rapid self-healing property which is confirmed by rheology statistics. Mechanical strength of the hydrogel was investigated from the rheology analysis and demonstrates good mechanical properties i.e. storage modulus (G') found to 107 pa. Further, the sustained release of hydrophilic drug i.e. levofloxacin from the hydrogel matrix at different pH range 6–7 has been carried out. Hydrogel with maximum cuminaldehyde amount releases max drug i.e. 96% while hydrogel with 6 mmol shows minimum drug release i.e.54%. Hydrogel shows controlled release of levofloxacin up to 90 h. The present research work revealed that produced hydrogel will become a promising candidate in biomedical field. © 2020
Effect of chitosan coating on postharvest diseases and fruit quality of mango (Mangifera indica)
(Indian Council of Agricultural Research, 2017) Barman, Kalyan; Patel, V.B.; Sharma, Swati; Singh, R.R.
The objective of this work was to study the effect of postharvest chitosan coating on fruit quality and shelf life of mango (Mangifera indica L.) during storage at ambient condition. Physiologically mature freshly harvested mango fruits (cv. Langra) were treated with chitosan solutions (0%, 0.5%, 0.75% or 1.0%) containing 0.5% acetic acid for 1 min and stored at ambient condition (25 ± 2°C, 85 ± 5% RH). Treatment with 1.0% and 0.75% chitosan significantly reduced weight loss and disease incidence of fruit compared to control. These treatments also maintained higher ascorbic acid, total phenolics content and total antioxidant activity than other treatments.However, development of peel colour and total carotenoids content in the fruit pulp was suppressed by chitosan 1.0% treated fruits. Treatment of mango with chitosan also delayed increase in the total soluble solids and decrease in titratable acidity compared to control. No significant differences were recorded between chitosan 0.75% and 1.0% treated fruits except for peel colour development and total carotenoids content. These results indicated that 0.75% chitosan coating could preserve fruit quality, reduce disease incidence and extend shelf life of mango up to 12 days during storage at ambient condition. © 2017, Indian Council of Agricultural Research. All rights reserved.
Effect of chitosan coating on postharvest quality and enzymatic activity of eggplant (Solanum melongena L.) cultivars
(Blackwell Publishing Ltd, 2021) Sharma, Swati; Prasad, R.N.; Tiwari, Shailesh; Chaurasia, S.N.S.; Shekhar, Shashi; Singh, Jagdish
Eggplant (Solanum melongena L.), an important fruit vegetable exhibits very limited postharvest marketability, particularly due to rapid moisture loss. This study assessed the variation due to chitosan coating on different eggplant cultivars (purple long, purple round, and white long). Fruit were coated with chitosan (1%) and stored at 10 ± 2°C. The chitosan-coated purple round cultivars (BR-14 and PR-5) had minimum weight loss and polyphenol oxidase (PPO) and peroxidase (POD) activity than long cultivars (Kashi Taru, IVBL-22, and Kashi Himani), while the functional quality (anthocyanins, total phenolics, and flavonoids) of long cultivars was higher. Chitosan was effective in minimizing weight loss by about two fold and retained higher flavonoids by about 1.2–2.3 fold over uncoated fruit in different eggplant cultivars. Chitosan-coated round (PR-5 and BR-14) and long (Kashi Himani, IVBL-22, and Kashi Taru) cultivars showed an increase in storability by 8 and 6 days, respectively, over uncoated fruit. Practical Applications: The coating of eggplants with chitosan is an easy to use, effective, economical, and biologically safe technique to enhance the postharvest keeping quality of eggplants. It can be employed in the postharvest supply chain to maintain quality and extend marketability of eggplants. © 2020 Wiley Periodicals LLC.
Effect of Pseudomonas fluorescens formulations on decay and quality of mango (Mangifera indica) fruits during storage
(Indian Council of Agricultural Research, 2017) Barman, Kalyan; Asrey, Ram; Singh, Dinesh; Patel, V.B.; Sharma, Swati
Anthracnose and stem-end rot caused by Colletotrichum gleosporioides and Botryodiplodia theobromae, respectively are the most important postharvest diseases of mango (Mangifera indica L.) causing huge economic losses. In this study, biocontrol efficacy of Pseudomonas fluorescens was evaluated against anthracnose and stemend rot of naturally infected mango fruits during their postharvest storage. Physiologically mature mango fruits were treated with P. fluorescens formulations (107 cfu/ml and 108 cfu/ml) by dipping them for 5 min. Following treatment, fruits were air-dried and stored at ambient condition (30° ± 2°C) for 12 days. Among the treatments, P. fluorescens 108 cfu/ml showed significant reduction (5.92%) in decay loss of mango fruit compared to control (24.52%). Respiration and ethylene evolution rates were also brought down by P. fluorescens treatments. Loss of firmness, total phenolics content and titratable acidity were also found lower in P. fluorescens treated fruits. No significant differences in a∗ and b∗ values of fruit colour was recorded between control and treated fruits while, the L∗ value was lowest in control fruits. The fruits treated with P. fluorescens @ 108 cfu/ml maintained highest total carotenoids and total soluble solids content than other treatments. Therefore, P. fluorescens @ 108 cfu/ml treatment may be used as a potential biocontrol agent in reducing anthracnose and stem-end rot, and maintaining desirable fruit quality attributes of mango during postharvest storage.
Effects of implementation of healthcare associated infection surveillance and interventional measures in the neonatal intensive care unit: Small steps matter
(Indian Association of Medical Microbiologists, 2023) Rakshit, Pue; Nagpal, Nitika; Sharma, Swati; Mishra, Kajal; Kumar, Ashok; Banerjee, Tuhina
Purpose: Neonatal sepsis has been a global concern considering the mortality and morbidity. This study was undertaken to determine the effects of implementation of interventions namely healthcare associated infection (HAI) surveillance and hand hygiene (HH) monitoring in the neonatal intensive care unit (NICU). Materials and methods: The cohort study was conducted in the NICU of a tertiary care hospital over a period of June–September 2021 (pre-intervention) to October–March 2022 (post-intervention). HAI surveillance of primary bloodstream infections (BSI) and HH monitoring was initiated as interventions post outbreak due to non-albicans Candida (NAC). The primary outcome of the interventions was to record any improvement in HH rates or any change in HAI rates in the 6 months intervention period. Characteristics of the pre- and post-intervention period were compared by Fisher exact test. Results: There was significant reduction in BSI cases in the post-intervention period (p < 0.05). Mortality and BSI due to NAC were significantly more in the pre-intervention period even though low birth weight neonates (<2500 g) were significantly more in the post-intervention period (p < 0.05). The HAI rate for primary BSI in the NICU was 10.82 per 1000 patient days. The overall adherence rate to HH was 10.68% (complete) and 73.35% (partial). HAI rates were seen to change reciprocally with changes in HH rates. Conclusions: HAI rates of primary BSI in the NICU could be regulated by the effective implementation of HAI surveillance, HH monitoring, feedback meetings with the NICU staff and other simple interventional measures even in resource-limited setups. © 2023 Indian Association of Medical Microbiologists
Effects of two Ayurvedic formulations, Dhanwantaram Kashaya and Saraswatarishta on life history parameters and toxic aggregates in Drosophila models of Huntington's and Alzheimer's disease
(Elsevier Ireland Ltd, 2023) Sharma, Swati; Singh, Girish; Patwardhan, Kishor
Ethnopharmacological relevance: Ayurveda, the traditional healthcare system native to India, employs dosage forms containing multiple herbs in treating various clinical conditions. Dhanwantaram Kashaya (DK) and Saraswatarishta (SA) are two such formulations containing multiple herbs in varied proportions. Kashaya is a liquid decoction while Arishta is fermented liquid with permissible quantity of self-generated alcohol in it. Both the formulations have been reported to have clinical efficacy in age-related memory impairment. Other mental disorders having clinical presentations similar to psychoses are the other indications for these tested formulations. Aim of the study: The present study was performed to evaluate the efficacy of two Rasayana formulations i.e., DK and SA, used by clinicians in different neurodegenerative conditions. We tested these formulations in Alzheimer's (AD) and Huntington's disease (HD) models of Drosophila melanogaster. Materials and method: Initial experiments looking for life-history parameters in wild-type larvae were carried out in three sets with hundred larvae in each set. These parameters were also studied in diseased models in four sets with eighty larvae in each set. Aβ plaques and polyQ aggregates were looked at with the help of immunostaining technique and images were captured using confocal microscopy. Results: The results revealed that 0.25% concentration of both the formulations improve longevity in wild-type flies. Larval development and adult lifespan in Eye-GAL4>Aβ42 (AD) and GMR-GAL4>127Q (HD) larvae/flies reared on 0.25% & 0.50% DK and 0.25% & 1.00% SA improved substantially. Reduced Aβ plaques and polyQ aggregates indicate disease suppression. Conclusion: DK and SA enhanced longevity in Drosophila melanogaster. Suppression of disease aggregates suggests their potential utility in treating AD and HD. Further clinical and pharmaceutical studies are required to confirm these results, however, this is a workable model to test multi-herbal formulations of Ayurveda in the forms they are clinically used. © 2023 Elsevier B.V.
Ethnobotany, Phytochemistry and Pharmacology of Palash (Butea monosperma (Lam.) Taub.): a Systematic Review
(Springer Science and Business Media Deutschland GmbH, 2022) Kumari, Poonam; Raina, Kirti; Thakur, Sunil; Sharma, Rohit; Cruz-Martins, Natália; Kumar, Pardeep; Barman, Kalyan; Sharma, Swati; Kumar, Dileep; Prajapati, Pradeep Kumar; Sharma, Rohit; Chaudhary, Ashun
Purpose of Review: Butea monosperma (Lam.) Taub. is an Indian traditional medicinal tree, aka “flame of forest,” “palash,” “bastard teak,” and “dhak.” The family comprises 630 genera and 18,000 species distributed throughout Asian countries. It is traditionally used since the Vedic era for different therapeutic purposes in various parts of India. This review is aimed to provide updated report on ethnobotany, phytochemistry, and pharmacological activities of B. monosperma that have been revealed till now. Recent Findings: This plant exhibits various pharmacological properties such as anti-helminthic, anti-conceptive, anti-stress, anti-estrogenic, antifertility, antimicrobial, chemopreventive, hypoglycemic, antioxidant, and anti-cancer effects because of specific metabolites present in its parts. Some of the most renowned phytochemicals present in it include flavonoids, alkaloids, terpenoids, proteins, lipids, and sterols. Earlier phytochemical studies have underlined several metabolites, including 3,4,2’,4’-tetrahydrochalcone-3,4-diglucoside (isobutrin), 7,3’,4’-trihydroxyflavanone-7,3’-diglucoside (butrin), cajanin, isoformononetin, stigmasterol, butein, medicarpin, and butinas responsible for their excellent pharmacological activities. Summary: Compelling evidence support the traditional ethnomedicinal claims of B. monosperma and its wide range of bioactivities are attributed to the rich phytocompounds present in this botanical. Further investigations are warranted to elucidate the mechanistic role of its bioactive compounds coupled with drug development processes and to explore the potential at clinical levels. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Evaluation Report of the Colistin Broth Disk Elution Method with Acinetobacter baumannii Isolates from a Low-Resource Setting
(American Society for Microbiology, 2022) Sharma, Swati; Banerjee, Tuhina; Garg, Rahul; Das, Padma
The rapid emergence of drug resistance in Acinetobacter baumannii has put forward the use of colistin as a last-resort treatment for infections with A. baumannii. Empirical colistin use without prior susceptibility testing has been one of the factors that has been promoting drug resistance in low-resource settings. In this regard, while the advocated broth microdilution (BMD) method for colistin susceptibility testing is often considered cumbersome, the preferable colistin broth disk elution (CBDE) method has not yet been approved for A. baumannii. To prevent the underreporting of colistin susceptibility, we tested the CBDE method for A. baumannii and compared the results with those of BMD. A total of 125 A. baumannii, including 100 susceptible and 25 resistant isolates were tested via the CBDE method and compared with the standard BMD method. The essential agreement, categorical agreement, sensitivity, and specificity for CBDE were 97.6% (n = 122), 98.4% (n = 123), 100%, and 98.40%, respectively. The percentage of major error found was 1.6% (n = 2), and no very major error was found. CBDE in A. baumannii could be considered in low-resource settings. IMPORTANCE The relatively cumbersome broth microdilution (BMD) method for routine colistin susceptibility testing has not been adopted, especially in low-resource settings, often leading to the underreporting of colistin susceptibility and the promotion of the empirical use of colistin. In this regard, the much-preferred colistin broth disk elution (CBDE) method has not yet been approved for A. baumannii. We evaluated colistin susceptibility via the CBDE method, compared the results with those of the BMD method in 125 A. baumannii isolates with various profiles, and inferred that the CBDE method using 50 mL inoculum could be helpful, at least in resource-limited setups, versus not reporting susceptibility testing for colistin. © 2022 Sharma et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.
Extensive outbreak of colistin resistant, carbapenemase (bla OXA-48, bla NDM) producing Klebsiella pneumoniae in a large tertiary care hospital, India
(BioMed Central Ltd, 2022) Sharma, Swati; Banerjee, Tuhina; Kumar, Ashok; Yadav, Ghanshyam; Basu, Sriparna
Background: Extensive drug resistance in Klebsiella pneumoniae (K. pneumoniae) causing major outbreaks in large hospitals is an emerging challenge. We describe a near fatal outbreak of colistin resistant, carbapenem resistant K. pneumoniae (CRKp) producing metallo beta-lactamases (blaNDM) and blaOXA-48 in the neonatal intensive care unit (NICU) at the background of a larger outbreak involving multiple parts of the hospital and the challenges in its containment. Methods: Following identification of an outbreak due to colistin resistant CRKp between April to June 2017 in the NICU, a thorough surveillance of similar cases and the hospital environment was performed to trace the source. All the isolated K. pneumoniae were tested for susceptibility to standard antibiotics by disc diffusion and microbroth dilution methods. Molecular detection of extended spectrum beta lactamases (ESBLs) and carbapenemases (classes A, B, D) genes was done. Enterobacterial repetitive intergenic consensus (ERIC) PCR and multi-locus sequence typing (MLST) was done to determine the genetic relatedness of the isolates. Characteristics of different sequence types were statistically compared (Student’s t-test). Results: A total of 45 K. pneumoniae isolates were studied from NICU (14 cases of neonatal sepsis), ICU (18 cases), other wards (7 cases) along with 6 isolates from hospital environment and human colonizers. The primary case was identified in the ICU. All the K. pneumoniae from NICU and 94.4% from the ICU were colistin resistant CRKp. Majority (59.37% and 56.25%) harbored blaSHV/blaCTXM and blaOXA-48 genes, respectively. Two distinct sequence types ST5235 and ST5313 were noted with colistin resistance, distribution within the NICU and mortality as significant attributes of ST5235 (p < 0.05). The outbreak was contained with strengthening of the infection control practices and unintended short duration closure of the hospital. Conclusion: Large hospital outbreaks with considerable mortality can be caused by non-dominant clones of colistin resistant CRKp harboring blaOXA-48 and blaNDM carbapenemases in endemic regions. The exact global impact of these sequence types should be further studied to prevent future fatal outbreaks. © 2022, The Author(s).
Extensively Drug-Resistant Hypervirulent Klebsiella pneumoniae From a Series of Neonatal Sepsis in a Tertiary Care Hospital, India
(Frontiers Media S.A., 2021) Banerjee, Tuhina; Wangkheimayum, Jayalaxmi; Sharma, Swati; Kumar, Ashok; Bhattacharjee, Amitabha
The recent emergence of multidrug-resistant (MDR) Klebsiella pneumoniae with hypervirulent traits causing severe infections and considerable mortality is a global cause for concern. The challenges posed by these hypermucoviscous strains of K. pneumoniae with regard to their optimal treatment, management, and control policies are yet to be answered. We studied a series of extensively drug-resistant (XDR) and hypervirulent K. pneumoniae ST5235 isolates with resistance to carbapenems and polymyxins causing neonatal sepsis in a tertiary care hospital in India. A total of 9 K. pneumoniae isolates from 9 cases of neonatal sepsis were studied with respect to their clinical relevance, antimicrobial susceptibility profile, presence of extended spectrum β lactamase (ESBL) production, and responsible genes, carbapenemases (classes A, B, and D), and aminoglycoside-resistant genes. Hypervirulence genes encoding hypermucoid nature, iron uptake, and siderophores were detected by multiplex PCR. The plasmid profile was studied by replicon typing. Isolates were typed by multilocus sequence typing (MLST) and enterobacterial repetitive intergenic consensus (ERIC) PCR to study the sequence types (STs) and clonal relation, respectively. The neonates in the studied cases had history of pre-maturity or low birth weight with maternal complications. All the cases were empirically treated with piperacillin–tazobactam and amikacin followed by imipenem/meropenem and vancomycin and polymyxin B as a last resort. However, all the neonates finally succumbed to the condition (100%). The studied isolates were XDR including resistance to polymyxins harboring multiple ESBL genes and carbapenemase genes (blaNDM and blaOXA−48). Hypervirulence genes were present in various combinations with rmpA/A2 genes present in all the isolates. IncFI plasmids were detected in these isolates. All belonged to ST5235. In ERIC PCR, 6 different clusters were seen. The study highlighted the emergence and burden of XDR hypervirulent isolates of K. pneumoniae causing neonatal sepsis in a tertiary care hospital. © Copyright © 2021 Banerjee, Wangkheimayum, Sharma, Kumar and Bhattacharjee.

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