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Background: Acinetobacter baumannii is a gram negative non-motile coccobacillus, which was considered as a low priority pathogen with low virulence. Recently, it was declared as the priority pathogen under the critical category of the most dangerous pathogen by WHO. Acinetobacter Baumannii is an inhabitant of oral biofilms, and it also increases the risk of refractory periodontitis. It causes nosocomial infections with pgaB, a part of pgaABCD operon which is involved in the biofilm formation. Aim: The aim of the present study was to detect the immunodominant peptides against pgaB of Acinetobacter baumannii using bioinformatic tools and databases. Materials and Methods: The present study was carried out using immune informatics. The protein sequence of the pgaB protein from A.baumannii was subjected to assess allergenicity, secondary structure, antigenicity and stability prediction of selected T cell epitopes, physico-chemical analysis, Identification of MHC class 2 binders, Final selection of B-cell epitopes was done with IEDB B-cell epitope tool Results: Final docking of the peptides were interpreted by hydrogen bonds and interac- tion scores with TLR-2. Promising scores on antigenicity, instability were obtained. Based on the combinatorial scores, one vaccine peptide (LNLTLGLAL) was suggested to be a promising vaccine candidate against pgaB of A.baumannii. Conclusion: The findings of the present study suggest epitope LNLTLGLAL as a promising vaccine candidate against pgaB of A.baumannii. The vaccine peptides targeting the pgaB Gene in A.baumannii using an immune-informatics approach suggests promising results in the present study. However, the predicted epitope peptides need further experimentation in animal models for its application against A.baumannii.

Introduction: Periodontal disease is an infection of the tissues that hold your teeth in place. It's typically caused by poor brushing and flossing habits that allow plaque, a sticky film of bacteria, to build up on the teeth and harden. Elimination of these pathogens from the site of infection remains a perplexing task, which demands the use of antibiotics. The emergence of drug resistant forms has spurred interest into identifying novel therapeutic targets against these pathogens. Aim: The present study employs virtual screening method to identify the protein network interaction of berberine with red complex pathogens. Materials and Methods: Computational tools were used to identify the targets, assess their functional role and virulence property. Further, the peptide epitopes present in the virulence factors were identified using the BepiPred tool. The subcellular location of the virulence proteins was also elucidated using PSORTb. Results: Berberine was found to target vital protein transporters such as TetR family transcriptional regulator and MerR family transcriptional regulator, which is known to play a crucial role in the survival of bacterial cells. Conclusion: Hence the present study provides preliminary data on the protein targets of berberine against red complex pathogens. However, in vitro studies using the compound is warranted to further confirm the efficacy of the compound.

Introduction: Opuntia ficus-indica is a well adapted cactus to extreme climatic environments. In the usual diet and food industry, it is an interesting source of food ingredients. In general, the protective role of prickly pears has been due to their antioxidant components, phenolic compounds, and some minor components present in the content of seed oil and seed protein and the oil from cactus pear seed has been found with high levels of unsaturated fatty acids ,with antioxidant and antimicrobial activity as well as cardioprotective, antithrombotic, anti-inflammatory, antiarrhythmic, hypolipidemic, and antihyperglycemic effect. Aim: To evaluate the in vitro antimicrobial activity of Opuntia ficus-indica seed oil against Streptococcus mutans. Materials and Methods: Broth microdilution assay was performed by following modifications: Brain heart infusion (BHI) broth was prepared and sterilise at 121c for 15lbs, the 100 microlitre of streptococcus mutans inoculated at freshly prepared broth and incubated at 37c for 24 hours. Then BHI broth prepared with sucrose and serial two fold dilution were done with 160microlitre broth and 40 microlitre prickly pear seed oil. Then 20 microlitre of culture was added. Column 11 contains BHI using sterile micro pipettes and the plates were incubated at 30 c for 18 hours. The growth of bacteria was visualised and lowest concentration with no visible growth was recorded as MIC. Results: This study results shows that, by broth microdilution method at concentration ranging from 10%-0.039% v/v, Opuntia ficus-indica seed oil potentially inhibits the growth of streptococcus mutans at the concentration of 0.03% (v/v). Conclusion: From the study, the results demonstrated that Opuntia ficus-indica seed oil shows noticeable antimicrobial activity against streptococcus mutans. Use of essential oils against oral pathogens can be an alternative to other antimicrobial agents which could be cheap and effective modules used in control of bacteria which are responsible for oral infections.

Introduction: Triclosan is considered to be an important ingredient in toothpastes and mouth rinses. Several studies have reported contradictory results regarding the antimicrobial effect of triclosan. Hence, the present in silico study intends to identify the potential targets of triclosan in two common dental pathogens Streptococcus mutans and Enterococcus faecalis. Aim: To identify the protein network interactions of triclosan in Streptococcus mutans and Enterococcus faecalis by virtual screening method. Materials and Methods: The STITCH v5.0 database was initially used for identifying drug-protein interactions followed by VICMPred and VirulentPred which was employed to identify functional class of the proteins and its virulence property. Finally, BepiPred v1.0 Linear Epitope Prediction tool was used to identify the potential epitopes of the virulent proteins. Results: Triclosan was found to interact with crucial proteins in S. mutans and E. faecalis which could contribute to severe forms of periodontitis and endodontic diseases. Conclusion: Taken together, the present study provides the preliminary data on the potential targets of triclosan in common dental pathogens. Further experimental validation is warranted to provide concrete evidence on the molecular targets of dental pathogens.

Introduction: HNSCC is a type of cancer in the oral and pharynx region. Several mutations/variations are observed in these cancer phenotypes. Fibroblast growth factor belongs to the family of heparin binding growth factors. FGFs are multifunctional proteins with a wide variety of effects; they are most commonly mitogens. Their expression pattern correlates with invasion of HNSCC. Aim: To assess the genetic alterations in genes of the fibroblast growth factor family and their association with HNSCC. Materials and Methods: The demographic data and samples of 528 HNSCC patients was collected from the cBioportal database. Oncoprint analysis was done to assess the amplification and genetic alterations of the members of the FGF gene family. String analysis was performed to evaluate the protein-protein interaction. The information about previous reported mutation and correlation with novel and reported mutation was obtained using GnomAD analysis. Results and Discussion: FGF3,4 and 19 genes showed maximum variation (25%). FGF4 and FGF19 genes showed maximum amplification in addition to deletion mutation. Excitingly FGF3, FGF4 and FGF19 genes showed similar amplification patterns in most of the HNSCC patients. Statistical significant difference in the gene expression of FGF3 9.578 x 10-3 observed between normal and primary tumour. S. Findings showed many novel mutations and also 4 reported mutations ie:FGF1, FGF12, FGF20, FGF21 Conclusion: Our present study concludes that more evidence is required to confirm their association with HNSCC.

Background: Antimicrobial drug resistance is the major problem encountered world-wide. Novel therapeutic leads have been identified and are regularly tested for their activity against microbial pathogens. Aim: To identify the protein network interactions of triclosan in red complex pathogens. Materials and Methods: The present study follows an observational study design which aims to screen for the interaction of triclosan in red complex pathogens. The interaction was analyzed using the STITCH v.5 pipeline. The functional class of proteins identified were assessed using VICMPred and VirulentPred softwares. The microbial pathogens Treponema denticola ATCC 35405, Tannerella forsythia ATCC 43037, Porphyromonas gingivalis ATCC 33277 are the strains of red complex pathogens that are included in the present study. Results and Discussion: Several proteins were found to interact with triclosan. Among the protein interactions, interactions of triclosan with virulent proteins seems to have a greater impact. The NAD-dependent nucleotide-diphosphate-sugar epimerase [PGN_1370], Putative NAD dependent epimerase [PGN_1886], GDP-fucose synthetase [PGN_1079], Probable oxidoreductase [PGN_1360] of Porphyromonas gingivalis, Conserved hypothetical protein [TDE_2401], Epimerase/dehydratase family protein [TDE_1439] of Treponema denticola, NAD dependent epimerase/dehydratase family protein [BFO_2919], Hypothetical protein [BFO_1782], Nitroreductase family protein [BFO_1604] and Nitroreductase family protein [BFO_1516] Tannerella forsythia were found to be exhibit virulence nature. Conclusion: This study identifies the molecular targets of triclosan on red complex pathogens. As triclosan interacts with the red complex pathogens, in future it can be used as a primary medicine for periodontitis and some oral conditions.

Introduction: Head and neck squamous cell carcinoma (HNSCC) is an aggressive life-threatening disease associated with high mortality rates. Several genes related to stress response have been studied extensively to reveal their possible association with HNSCC. Members of the HSPA (heat shock protein family A) family are exclusively expressed under stress conditions suggesting that these are specialised to function in the stress response. Aim: The aim of the present study is to demonstrate the genetic alterations in the HSPA gene family and their putative association with HNSCC. Materials and Methods: The source of the patient's data was procured from the cBioportal database. The TCGA Firehose Legacy comprised 528 head and neck squamous cell carcinoma cases. Oncoprint data analysis can be used to derive a putative association between the disease phenotype and genotype, to identify the variations and to identify any novel variations which can be associated with the disease phenotype. The gnomAD data analysis was used to compare between the observed variants documented in the present study with that of reported variants deposited in the gnomAD repository. Results and Discussion: The HSPA1A&HSPA1B genes harboured high frequency of amplification and deep deletions. The expression of two genes HSPA8 and HSPA13 was found to be up-regulated in the primary tumor sample in comparison to normal tissues. In Kaplan Meier analysis, HSPA8 gene expression was compared with gender, here, high expression in females shows low survival rate. Similarly, HSPA13 gene expression was compared with race, here low expression in africanamerican population shows low survival rate. Conclusion: The present study provides preliminary data on the involvement of the HSPA family of genes with HNSCC, which has to be validated using experimental evidence in other populations.

Background : Hepatitis B is a potentially life-threatening liver infection caused by the Hepatitis B virus (HBV). It is a major global health problem and the most serious type of viral hepatitis. It can cause chronic liver disease and puts people at high risk of death from cirrhosis of the liver and liver cancer. HBV is found in highest concentrations in blood and in lower concentrations in other body fluids. Methods: Target protein was retrieved from the swissprot database. Epitopes were predicted using the BCEPRED server. After running the BLAST algorithm for the target protein, the template with the best identity was selected. After modeling, target protein is verified by using the swiss model workspace and after this process the obtained target protein is allowed to interact with the MHC which is studied by using patchdock, finally these results were viewed by using the deepview tool. Results: The target protein for vaccine development was downloaded from the SwissProt database. Its SwissProt ID was p29178. The protein was isolated from hepatitis B virus genotype G. The virus was isolated from the United States of America. The length of the target protein was found to be 195 amino acids. To confirm that the target protein could be used for vaccine development, the Presence of epitopes in the protein was confirmed using the BCEPRED tool. Results from the SAVS server showed 95.80 of the residues of the protein had an average 3D-1D score greater than 0.2. The protein attained a pass with an ERRAT value of 90.299. Conclusion: The present investigation recognized the promising complex formed between the HBV peptide and MHC molecules. All the downloaded MHC molecules were found to interact with the target protein through the formation of hydrogen bonds. Since these interactions are necessary during an immune response to invading pathogens, the target protein would ultimately trigger an immune response if it is administered as a vaccine for Hepatitis B virus genotype G.

At present, processing of medical images is a developing and important field. It includes many different types of imaging methods. Some of them are Computed Tomography scans (CT scans), X-rays and Magnetic Resonance Imaging (MRI) etc. These technologies allow us to detect even the smallest defects in the human body. Abnormal growth of tissues in the brain which affect proper brain functions is considered as a brain tumor. The main goal of medical image processing is to identify accurate and meaningful information using images with the minimum error possible. MRI is mainly used to get images of the human body and cancerous tissues because of its high resolution and better quality images compared with other imaging technologies. Brain tumor identifications through MRI images is a difficult task because of the complexity of the brain. MRI images can be processed and the brain tumor can be segmented. These tumors can be segmented using various image segmentation techniques. The process of identifying brain tumors through MRI images can be categorized into four different sections; pre-processing, image segmentation, feature extraction and image classification.

The management of post-consumer discarded plastic wastes (PCPW) creates new challenges in developing countries due to the lack of amenities, technological interventions, and associated negative environmental externalities. The fate of untreated recyclable and non-recyclable plastic wastes lies in open dumping along with other solid waste, and improper management leads to environmental externalities such as pollution, global climate change, and health issues. Additionally, open dumping upsurges the emerging microplastics and nano plastics (MNPs) contaminants. The externalities depend on the waste generating sources (household, industries, commercial), waste composition, and its characteristics. However, urban mining can minimize environmental externalities where waste plastics can convert into potential anthropogenic resources and also helps in achieving the target of sustainable development goals (SDGs 1112). Moreover, various treatment technologies that help in the sustainable utilization of plastic wastes are extensively reviewed in this study and evaluate the costs benefits arising during various stages of treating plastic waste through recycling (R), incineration (I), and landfilling (L). The recycling of plastic waste has demonstrated the lowest impact on global warming potential (GWP) and total energy use (TEU), followed by landfilling and incineration (RLI). Nevertheless, when energy is recovered from inert (non-recyclable) plastic waste in the form of fuel or by its utilization in construction purposes, the environmental impacts are more negligible (IncinerationLandfilling). Therefore, this study determines the significance of circular economy with legislative approach and standards on plastic waste management, which help in reducing environmental externalities besides yielding a secondary resource as energy and materials through urban mining. A sustainable plastic waste management (SPWM) model is proposed for developing countries to convert plastic waste into resources and use it as a sustainable tool in urban mining.

This paper demonstrates a simple-in-struct- ure, cost-effective, and environment-friendly Microfluidic Paper-based Analytical Device for Microbial Biofuel Cell ( $\mu $ PAD-MBFC). It consists of a microchannel with biofuel cell (Escherichia.Coli) and an oxidant (aerated tap water) flowing co-parallelly over Multiwalled Carbon Nanotube (MWCNT)-based Bucky Paper (BP) electrodes using a self-capillary and co-laminar flow mechanism. The electrochemical studies, such as open circuit potential (OCP) and polarization were evaluated using a potentiostat. Various volumetric bacterial studies were also carried out to find out the best suitable optimal bacterial volume. Subsequently, the morphological and detailed element composition study of electrode surface was performed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. This well-designed portable $\mu $ PAD-MBFC yields a maximum power density of 4 $\mu \text{W}$ /cm2 ( $20~\mu \text{A}$ /cm2) at 0.405 V over $200~\mu \text{l}$ of culture and leveraging to its long-lasting potential to operate miniaturized microelectronics sensors and portable devices.

Burkholderia pseudomallei is the causative agent for melioidosis. Because of its intracellular nature, the bacterium is capable of replicating within a plethora of eukaryotic cell lines. B. pseudomallei can remain dormant within host cells without symptoms for years, causing recrudescent infections. Here, we investigated the pathogenesis mechanism behind the suppression of T cell responses by B. pseudomallei . Peripheral blood mononuclear cells (1×106 cells/well) isolated by Ficoll Paque (Sigma-Aldrich) density gradient centrifugation were incubated with optimized concentrations of bacterial crude culture filtrate antigens (CFAs) (10 ug ml−1) and heat-killed bacteria [1 : 10 multiplicity of infection (m.o.i.)]. Following incubation, cells were investigated for surface expression of coinhibitory molecules by flow cytometry. We found that B. pseudomallei induced the upregulation of programmed death 1 (PD-1), a molecule responsible for T cell exhaustion, on T cells in vitro following exposure to crude CFAs of B. pseudomallei . This upregulation of PD-1 probably contributes to poor immune surveillance and disease pathogenesis.

Anaerobic digestion of food waste and concomitant production of methane-rich biogas will vary majorly depending on the quality of the inoculum, and due to the presence or absence of inhibitory substances. This study focuses on the effect of two types of inocula on anaerobic digestion of food waste. For this study, two laboratory-scale digesters, with working volume of 40 L, were used. While one of the digesters was inoculated with cow dung (digester 1), the other was inoculated with sludge obtained from an UASB reactor treating municipal sewage (digester 2). Both the digesters were maintained at mesophilic conditions (38 °C), and the initial pH of the digester mixture was adjusted to 7. Feeding was done daily, based on Ripley’s ratio, and the average mass of the food waste fed daily to the digesters was 150 g. The digesters were operated for a period of 112 days. As the digesters started stabilizing, Ripley’s ratio was in the range of 0.085–0.5 in digester 1, and in digester 2, it was 0.157–0.6. The VFA concentration was in the range of 1000–3500 ppm and 1300–4000 ppm in digesters 1 and 2, respectively. The cumulative biogas production was 6531 L in digester 1 and 6761 L in digester 2. From the results, it was clear that there was only marginal difference in the biogas production between the digesters. The effect of inocula in the anaerobic digestion of food waste was minimal; however in terms of conversion rate of VFAs to biogas, digester 2 was operating better at mesophilic conditions.

Pseudomonas aeruginosa use small signaling molecules such as acyl homoserine lactones (AHLs), which play an important role in release virulence factors and toxin for further establishment of host infection. Thus, involving with the QS system would provide alternative ways of preventing the pathogenicity. In the present study, totally six medicinal plants (Terminalia bellerica, Celastrus paniculatus, Kingiodendron pinnatum, Schleichera oleosa, Melastoma malabathricum, Garcinia gummi-gutta) were screened for anti-QS activity using biomonitor strain of Chromobacterium violaceum CV12472. The primary screening of antimicrobial activity of all the plant extracts have inhibited the growth of tested bacterial species. Of these at the sub-minimum inhibitory concentration the methanol extract of T. bellerica (0.0625–0.5 mg/ml) has significantly inhibited violacein production (20.07–66.22%) in C. violaceum (CV12472). Consequently, the extract of T. bellerica has reduced the production of pyocyanin, exopolysaccharide and biofilm formation in P. aeruginosa strains. Fluorescence and scanning electron microscopy analysis confirmed the reduction of biofilm formation in P. aeruginosa strains when treated with T. bellerica. GC–MS analysis showed the active compounds inhibited the production of virulence factors of P. aeruginosa. The results suggest the possible use of this T. bellerica as an anti-QS and anti-biofilm agent to control Pseudomonas infection. Interference of QS provides an important means for the inhibition of bacterial virulence and thus aids in treatment strategies., Graphical abstract Image 1

The spatiotemporal distribution, diversity and biomass of the choreotrich ciliate tintinnid, the ubiquitous planktonic protist, were analysed from nine sampling sites ( n = 252 ) of diverse environmental stresses along the Hooghly Estuary, eastern part of India during March 2012 to August 2014. Among 32 identified tintinnid species, the agglomerated genera Tintinnopsis (20 sp), dominated the community (∼62%) followed by Tintinnidium (2 sp), Leprotintinnus (2 sp), Codonellopsis, Stenosemella, Helicostomella, Favella, Eutintinnus, Metacylis, Dadayiellaand Wangiella (each comprising single species). A wide range of seasonal variations in tintinnid abundance was recorded maximum (2067±893 ind. l−1) for Tintinnopsis beroidea and minimum (11±4 ind. l−1) for Metacylis sp. during the investigation period. The biomass and daily production rate of tintinnid ranged from 0.004–2.764 μg C l−1 and 0.04–3.54 μg C l−1 day−1 respectively. An overall dominance and diversity of the small-sized tintinnid (lorica length k , showed species dominance over the investigated sites. The multidimensional scaling (MDS) Canonical Analysis of Principal coordinates (CAP) highlighting a significantly different spatial distribution of tintinnid. Principal Component Analysis (PCA) map showed clustering of core species with chl a and nitrate and could be considered as the crucial factors controlling the distribution and seasonal patterns of tintinnid. Biota-environment (BIOENV) analyses also reveal that these two parameters were the significant causative factors, suggesting that tintinnid may be used as a bioindicator for discriminating water quality in this estuarine system. The study provided detailed information of microzooplankton which enhances our understanding regarding its crucial role in marine ecosystem and complex biotic interactions for maintaining the ecological and economic stability.

Dengue virus (DENV) infection has become an increasingly common concern in tropical and subtropical regions. It has protean manifestations ranging from febrile phase to severe life-threatening illness. In this study, we estimated Th1 and Th2 cytokines and correlated the levels with dengue severity along with certain hematological and biochemical parameters. We also studied the seroprevalence of dengue between October and December 2017 at the Government Theni Medical College, India. Individuals with dengue fever (DF) were positive for either IgM or IgG, or both. The biochemical and hematological parameters along with plasma tumor necrosis factor alpha (TNF

An annual community structure of the loricate ciliate tintinnids, the ubiquitous planktonic protist, was analysed from nine sampling sites ( n = 108 ) of diverse environmental stresses along the Hooghly (Ganges) River Estuary, eastern coastal part of India. The agglomerated genus Tintinnopsis sp., was dominated among the 32 identified tintinnid species (3 core, 12 seasonal and 17 occasional species) contributing ∼62% of total tintinnid population. The size-class distribution of lorica oral diameter ranges between 9 and 22 μm for majority of the tintinnids (∼71%) which provides relevant information on the ecological characteristics for the species assemblages. The maximum species diversity for tintinnid ( H ′ = 1.71 ) during postmonsoon (February, 2014) has been attributed by high numerical density of phytoplankton dominated by diatoms (4400 cells l − 1 , H ′ = 3.41 ) at the site Gangasagar, mouth of the estuary. The large-sized tintinnids Tintinnopsis cylindrica (lorica length = 262.8 μm; lorica oral diameter = 65 μm) and T. radix (lorica length = 278.6 μm; lorica oral diameter = 62 μm) belonging to family Codonellidae, formed successful dominant group (>50% of the total) in this estuarine ecosystem. The core species abundance ( Tintinnopsis beroidea, Tintinnidium primitivum and Leprotintinnus simplex ) shares ∼57% of total tintinnid population followed by seasonal (35%) and occasional species (8%), characterized by their eurythermal and euryhaline nature. As revealed from the results of cluster analyses, majority of the tintinnids formed an individual functional group, exhibiting similar assemblages in species distribution. The Canonical Correspondence Analysis map (CCA) revealed a clustering of core species with the phytopigment (Chlorophyll a ) and dissolved oxygen which were found to be the most important causative factors controlling the distribution and seasonal patterns of tintinnids. Well-defined tintinnid assemblages are evident representing the fingerprint of the specific ecological zone of Hooghly estuary, characterized by a set of environmental variables.

Pathogenic Pseudomonas species produce virulence elements and form biofilm through quorum sensing (QS) system. Clinical infections caused by Pseudomonas aeruginosa are becoming increasingly tough to treat on account of wide spread drug resistance. The drugs have lost their efficacy due to the virulence elements and biofilms, which are responsible for increased severity of the infection. The search for novel drugs has increased and novel modes of action against Gram-negative pathogenic bacteria are been much more of important. Plants secondary metabolites are widely used for treating the many bacterial diseases. Plant-derived anti-QS and anti-biofilm compounds that do not negatively affect the growth of the bacterial cells, but rather attenuates the QS controlled virulence factors, that might allow the host defense to act more effectively to washout the P. aeruginosa infection. In this review mainly focus on overview of pathogenicity, QS controlled virulence factors and biofilm formation of P. aeruginosa infection. This review describes a brief account of QS inhibitors and anti-biofilm compounds, which exhibit alternative medicine possible for treating drug resistant P. aeruginosa.

Pseudomonas aeruginosa is an important opportunistic pathogen causing widespread infections by numerous virulence factors. The present investigation was to evaluate the antimicrobial and anti-quorum sensing (anti-QS) activities of essential oils (EOs) from Cuminum cyminum, Zingiber officinale, Myristica fragrans, Syzygium aromaticum, Cinnamomum verum, Rosmarinus officinalis, and Curcuma longa against the wild strain of Chromobacterium violaceum CV12472, clinical strain of P. aeruginosa (MM-1) and P. aeruginosa PAO1. All the EOs have shown antimicrobial activity against CV12472. Among these, five EOs namely C. cyminum, S. aromaticum, C. verum, R. officinalis and C. longa have shown anti-QS activity as evidenced by inhibition of violacein production. S. aromaticum and C. verum have shown promising anti-QS activity at very low concentration of 0.006 %, v/v and 0.01 %, v/v respectively. The study also analysed against the PAO1 and P. aeruginosa (MM-1). The MM-1 strain was resistant to the tested broad...

The antibiofilm activity of Murraya koenigii essential oil (EO) against Pseudomonas aeruginosa PAO1 was investigated in this study. A decrease in the production of rhamnolipid, extracellular polymeric substance and swarming motility was observed by the EO treatment (0.3% v/v). The static microtitre plate assay revealed 80% reduction in biofilm formation by P. aeruginosa PAO1 on M. koenigii EO treatment. Fluorescence microscopy and scanning electron microscopy analyses confirmed the reduction of biofilm formation in P. aeruginosa PAO1 when treated with M. koenigii EO. Gas chromatography–mass spectrometry analysis of the EO revealed the presence of well-known antibiofilm agents such as spathulenol (5.85%), cinnamaldehyde (0.37%) and linalool (0.04%). Cinnamaldehyde has not been previously reported in M. koenigii EO. The potent antibiofilm properties of M. koenigii EO may be effectively exploited in food and pharmaceutical industries as well as in controlling Pseudomonas biofilms on indwelling medical devices.

The work investigates on the potential of ten mangrove species for absorption, accumulation and partitioning of trace metal(loid)s in individual plant tissues (leaves, bark and root/pneumatophore) at two study sites of Indian Sundarban Wetland. The metal(loid) concentration in host sediments and their geochemical characteristics were also considered. Mangrove sediments showed unique potential in many- fold increase for most metal(loid)s than plant tissues due to their inherent physicochemical properties. The ranges of concentration of trace metal(loid)s for As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn in plant tissue were 0.006-0.31, 0.02-2.97, 0.10-4.80, 0.13-6.49, 4.46-48.30, 9.2-938.1, 0.02-0.13, 9.8-1726, 11-5.41, 0.04-7.64, 3.81-52.20 μg g (-1)respectively. The bio- concentration factor (BCF) showed its maximum value (15.5) in Excoecaria agallocha for Cd, suggesting that it can be considered as a high-efficient plant for heavy metal bioaccumulation. Among all metals, Cd and Zn were highly bioaccumulated in E. agallocha (2.97 and 52.2 μg g (-1) respectively. Our findings suggest that the species may be classified as efficient metal trap for Cd in aerial parts, as indicated by higher metal accumulation in the leaves combined with BCF and translocation factor (TF) values.

The global emergence of antibiotic-resistant strains of Pseudomonas aeruginosa poses a major threat in both hospital environments and the community. P. aeruginosa is an opportunistic human pathogen, and it also infects a wide range of model organisms including the nematode Caenorhabditis elegans. Quorum sensing (QS) mediates cell-to-cell communication in bacteria and has an important role in regulating virulence genes, antibiotic resistance and biofilm formation, which are crucial for establishment of the infection. Expression of many virulence factors such as pyocyanin and proteases in P. aeruginosa is under the control of the QS system, and are mediated by small molecules such as acyl homoserine lactones. Thus, interfering with the QS system would provide alternative ways of controlling the pathogenicity. Murraya koenigii is a medicinal plant widely used in India. The present study investigated the in vivo inhibitory activity of M. koenigii essential oil (EO) on QS-controlled virulence factors of P. aeruginosa PAO1 using C. elegans. M. koenigii EO significantly inhibited the pyocyanin production and staphylolytic LasA activity of P. aeruginosa PAO1. As compared to the control group with 100 % killing of C. elegans, M. koenigii EO was able to rescue an average of 60 % of C. elegans from death due to the toxic effect of P. aeruginosa. Thus, the present study suggests the anti-QS potential of M. koenigii EO which therefore can be considered as a future therapeutic agent for management of P. aeruginosa-mediated infections.

The biosynthesis of silver nanoparticles (AgNps) has a wide range of applications, and here we develop a rapid synthesis using the leaf extract of Ipomea carnea. We demonstrated that 100 mL of a 1 mM silver nitrate solution was reduced to AgNps by 500 µL of I. carnea extract in 5 min and that one or more of the chemical constituents present in the extract acted as the reducing agent. Surface plasmon resonance peaks were observed from 410 to 440 nm for AgNps synthesised using the plant extract, and the peaks showed a characteristic blue shift with variation of pH from 2 to 8. Particle size analysis revealed the size of the AgNps to be from 30 to 130 nm, which was also confirmed by dynamic light scattering, atomic force microscopy and transmission electron microscopy. Additionally, the antibacterial effects of the AgNps were evaluated against selected human pathogens such as Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Klebsiella pneumoniae, Aeromonas hydrophila, Salmonella typhi, Proteus vulg...

Vermicomposting of the pre-composted leaf litter of acacia (Acacia auriculiformis) was studied in reactors of identical volume but with surface area: height ratios varying from 4 to 250. In separate sets of experiments with these reactors, epigeic earthworm species Eudrilus eugeniae and anecic earthworm species Lampito mauritii were employed at densities of 75 and 150 adult animals per litre of reactor volume. The results reveal that greater the surface area: volume ratio of the reactor, higher is the vermicast output in terms of vermicast output per animal; the more densely populated reactors were comparatively under-productive. Even as the vermicast production remained consistently high in all the reactors, there was significant earthworm mortality throughout the course of the experiments and the worms who survived, steadily lost weight with time. A detailed investigation of the possible causes revealed that, whereas the C:N ratio of acacia compost was comparable with that of other substrates; the polyphenols and lignin content were much higher. Studies by other authors on leaf litter consumption by earthworms in natural or man-made forests have indicated that leaf litter rich in polyphenols and lignin are not preferred by most species of earthworm. This may perhaps be the reason for the high rate of mortality and weight loss in earthworms forced to feed upon acacia in the experiments conducted by the authors.

Studies are presented on new types of anaerobic digesters in which chopped or dry crushed Ipomoea carnea was fed without any other pretreatment, in an attempt to develop commercially viable means of utilizing the otherwise very harmful plant. Two types of solid-feed anaerobic digesters (SFADs) were studied. The first type had a single vessel in which the bottom 35% portion was separated from the top portion by a perforated PVC disk. The weed was charged from the top and inoculated with anaerobically digested cowdung-water slurry. The fermentation of the weed in the reactor led to the formation of volatile fatty acids (VFAs) plus some biogas. The leachate, rich in the VFAs, was passed through the perforated PVC sheet and collected in the lower portion of the vessel. The other type of reactors had two vessels, the first one was fully charged with the weed and the second received the VFA leachate. With both types were attached upflow anaerobic filters (UAFs) which converted the leachate into combustible biogas consisting of approximately 70% methane. All SFADs developed very consistent performance in terms of biogas yield within 17 weeks of start. The two-compartment reactors yielded significantly more biogas than the single-compartment reactors of corresponding total volume, and the reactors with which anaerobic filters (AF) were attached yielded more biogas than the ones without AF. The best performing units generated 2.41m(3) of biogas per m(3) of digester volume, as compared to 0.1-0.2m(3) of biogas, m(-3)d(-1), obtainable with conventional digesters. This indicates the viability of this technology. The spent weed can be vermicomposted directly to obtain good soil-conditioner cum fertilizer; earthworm Eudrilus eugeniae produced 540mg vermicast per animal every day, achieving near total conversion of feed to vermicast in 20 days. The proposed systems, thus, makes it possible to accomplish total utilization of ipomoea.

The antibiofilm activity of Murraya koenigii essential oil (EO) against Pseudomonas aeruginosa PAO1 was investigated in this study. A decrease in the production of rhamnolipid, extracellular polymeric substance and swarming motility was observed by the EO treatment (0.3% v/v). The static microtitre plate assay revealed 80% reduction in biofilm formation by P. aeruginosa PAO1 on M. koenigii EO treatment. Fluorescence microscopy and scanning electron microscopy analyses confirmed the reduction of biofilm formation in P. aeruginosa PAO1 when treated with M. koenigii EO. Gas chromatography–mass spectrometry analysis of the EO revealed the presence of well-known antibiofilm agents such as spathulenol (5.85%), cinnamaldehyde (0.37%) and linalool (0.04%). Cinnamaldehyde has not been previously reported in M. koenigii EO. The potent antibiofilm properties of M. koenigii EO may be effectively exploited in food and pharmaceutical industries as well as in controlling Pseudomonas biofilms on indwelling medical devices.

A procedure has been developed for extracting volatile fatty acids (VFAs) from water hyacinth (WH) using simple and inexpensive equipment of the type commonly available in the rural households of the third world countries. The VFAs thus extracted were used as feed supplement in cow dung-fed floating-dome biogas digesters. As tens of thousands of such digesters are in operation across the third world, the aim of these studies has been to provide for such digesters feed derived from phytomass, especially for use whenever animal dung is in short supply or is unavailable. The VFA extraction was based on aerobic/facultative degradation of water hyacinth and significant quantities were extracted from each WH charge daily for upto 6 days. When cow-dung slurry was fortified with the VFAs and fed to a conventional biogas digester, it yielded about 22% higher quantity of biogas per unit feed than was obtained from equivalent mass (dry weight basis) of the unfortified cow-dung slurry. The technique developed by us enables phytomass to be utilized as feed supplement in biogas digesters without causing the problems of solids accumulation, frothing and clogging known to be associated with phytomass feed. After VFAs have been extracted from it, the ‘spent’ water hyacinth was vermicomposted and used as soil conditioner-cum-fertilizer.

Epigeics, such as Eudrilus eugeniae, Eisenia fetida and Perionyx excavatus are humus-feeder earthworms which, in natural environments, mostly dwell in the humus and leaf litter lying over the top soil and have very shallow borrows. In order to make the most of this characteristic of the epigeics, we have simplified the design of epigeic-based vermireactors by doing away with layers of gravel, sand and soil, normally used for maintaining the other types (anecic and endogeic) of earthworms in the vermireactors. Instead, we have laid a moistened cotton cloth at the bottom of the circular vermireaction tank and have laid the feed over it. This arrangement provides the epigeics with a thin, moisture-rich, layer of solids beneath the humus-like compost used in the reactors as feed. The bottom layer mimics the moist soil below the mulch and humus which the epigeics use for their shallow burrows in natural environments. By doing away with the conventionally used elaborate vermibed, which used to take up ∼5% of the vermireactor volume in conventional systems, we have effectively increased the utilizable fraction of the reactor volume, thereby enabling a much higher feed throughput per litre of the reactor. Six month long operation of the conventional and the modified vermireactors in two concurrently run batches – one operating at low density of E. eugeniae and the other in high-rate mode – revealed that vermicast production per litre of reactor volume in both batches of modified reactors was dramatically higher than the output in the corresponding conventional reactors.