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Most bacteria exist in nature in the form of biofilms. One of the key survival strategies by bacteria to withstand chemical and physical stresses is by forming biofilms on biotic and abiotic surfaces. A different set of genes are expressed in biofilms compared to the planktonic mode of bacterial growth. According to data from the National Institutes of Health (NIH) and Centers for Disease Control and Prevention (CDC), nearly 80 percent of all human infections are encouraged by biofilms and roughly 65 percent of all hospital-acquired infections are associated with biofilms. Hence, considering the role of biofilms in clinical settings, there is an urgent need for the discovery/development of novel antibiofilm agents. In this study, we have tested the effect of freshly prepared titanium dioxide nanoparticles (TiO2-NPs) synthesized using Carum copticum extract on biofilms, both against Gram +ve and Gram −ve bacteria. Being environment friendly in nature, the green route of nanoparticle synthesis is believed to be advantageous over chemical synthesis of metal nanoparticles. The synthesized nanoparticles were found to be predominantly spherical or spheroidal in shape with an average size of 12.01 ± 5.58 nm. As evident from data, more than 70% inhibition of biofilms of test bacteria was achieved in the presence of TiO2-NPs. Electron microscopic analysis revealed that the adherence and colonization of bacteria on the glass surface were remarkably reduced by the treatment of TiO2-NPs. The EPS secretion of E. coli ATCC 25922 and P. aeruginosa PAO1 were inhibited by 62.08 and 74.94%, respectively. The EPS secretion of S. aureus MTCC 3160 was least inhibited (

The development of a transition-metal-based catalyst with concomitant high activity and stability due to its distinguishing characteristics, yielding an abundance of active sites, is considered to be the bottleneck for the dry reforming of methane (DRM). This work presents the catalytic activity and durability of SrNiO3 and CeNiO3 perovskites for syngas production via DRM. CeNiO3 exhibits a higher specific surface area, pore volume, number of reducible species, and nickel dispersion when compared to SrNiO3. The catalytic activity results demonstrate higher CH4 (54.3%) and CO2 (64.8%) conversions for CeNiO3, compared to 22% (CH4 conversion) and 34.7% (CO2 conversion) for SrNiO3. The decrease in catalytic activity after replacing cerium with strontium is attributed to a decrease in specific surface area and pore volume, and nickel active sites covered with strontium carbonate. The stability results reveal the deactivation of both the catalysts (SrNiO3 and CeNiO3) but SrNiO3 showed more deactivation than CeNiO3, as demonstrated by deactivation factors. The catalyst deactivation is mainly attributed to carbon deposition and these findings are verified by characterizing the spent catalysts.

The emergence of multidrug resistance in bacterial pathogens has increased drastically and it has become prevalent in clinical infections. In last few decades, there is a large gap in the discovery of new antibiotics with novel mode of action. The situation of antimicrobial resistance has become so alarming that if not action is taken, infectious diseases will become major cause of global mortality and morbidity by 2050. The growing interest of researchers in nanotechnology and their possible application in healthcare is being seen as a new hope in discovery of novel antimicrobial agents. Among various approaches employed for the nanoparticle synthesis, biological methods are considered more advantageous and environment friendly. Biofilms are considered as novel target for the development of new antimicrobial entities. In this study, cerium oxide nanoparticles (CeO2 -NPs) were synthesized using Acorus calamus aqueous extract and tested for the antibiofilm activity both against Gram +ve and Gram -ve bacteria. The average size of synthesized CeO2 -NPs was found to be 22.03 nm. The biofilms of the test bacteria were inhibited by more than 75% by the treatment with CeO2 -NPs. The quantitative biofilm data were further verified by light microscopy, electron microscopy, and confocal microscopy. The confocal and electron microscopic analysis confirmed that treatment with CeO2-NPs reduced the development and colonization of the bacteria on solid support. Moreover, it was found that the colonization and biofilm development by test bacteria were fairly reduced on the glass surface. Moreover, a dose-dependent inhibition of preformed biofilms was also found. The exopolysaccharides (EPS) production by the test bacteria were substantially reduced by the supplementation of CeO2 -NPs in culture media. The findings of this study highlight the efficacy of cerium oxide nanoparticles against bacterial pathogens that may be exploited for the development of new alternative antimicrobial agent.

Objective The current study designed to investigate the protective efficacy of maslinic acid (MA) and gallic acid (GA) against isoproterenol (ISO) administered cardiac toxicity in rats by exploring in vivo and in silico approaches. Methods The animals were divided into five different groups. The individual animal groups were orally pretreated with MA (15 mg/kg) and GA ((15 mg/kg) for 7 days and ISO administered subcutaneously on 8th and 9th days to induce MI. Blood, heart and liver were collected from sacrificed animals and used for biochemical analysis. Results The results represented significant decrease in the levels of high density lipoprotein cholesterol, lipoprotein lipase and lecithin cholesterol acyl transferase whereas significant increase in the levels of total cholesterol, triglycerides, low density lipoprotein cholesterol, very low density lipoprotein cholesterol and HMG-CoA reductase in ISO (85 mg/kg) treated rats. However, pretreatment of ISO treated rats with MA and GA markedly brought all the parameters such as lipids, lipoproteins and lipid metabolic marker enzymes to near normal level indicating the ameliorating effect of MA and GA against MI. Further, the investigation extended to in silico analysis to study the interaction of MA and GA with the key lipid metabolizing enzymes by using Gold 3.0.1 software. The molecular docking studies revealed that HMG-CoA reductase, LPL and LCAT formed strong enzyme ligand complexes with MA and GA. Conclusions MA and GA exhibited protective efficacy against ISO administered cardiotoxicity and the results further supported by molecular docking studies.

The formation of bacterial biofilms is a severely encountered problem in clinical and industrial settings. Most of the naturally occurring bacterial strains are capable of forming mono or mixed biofilms. In this study, we evaluated the potentiality of three clinically relevant species in forming mono and mixed biofilms over glass surface. In addition, we also appraised the efficiency of bacteriophages in alleviating preformed mono and mixed biofilm. Our initial study focused on the ability of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa in forming biofilm on glass cover slip. All the three strains were able to form mono biofilm, although at varying intensities. Interestingly, E. coli inhibited the formation of S. aureus biofilm in a mixed culture. Specific bacteriophages ɸ44AHJD and ɸX174 completely disrupted S. aureus and E. coli preformed biofilm structure after 72 hr of incubation. However, addition of either of the bacteriophage to the mixed E. coli-S. aureus promoted the formation of biofilm by the alternate strain that was not affected by the phage. Our findings elicit the potentiality of common bacterial strains in forming biofilms on smooth glass surface. In addition, these results are very promising for the development of effective drugs using intact bacteriophages for the removal of complicated bacterial biofilms formed in clinically relevant glass surfaces. The observations further complemented the earlier finding of competitive inhibition of S. aureus biofilm development by E. coli.

In recent times, agricultural practices mainly rely on agrochemicals and pesticides to safe-guard edible crops against various pests and to ensure high yields. However, their indiscriminate use may cause severe environmental hazards that directly and negatively affect soil microorganisms and crop productivity. Considering these, present study was aimed to assess the toxicity of carbamate pesticides namely carbamoyl (CBL), methomyl (MML) and carbofuran (CBN) using bacterial and plant (Vigna mungo L.) bioassays. All pesticide doses (25–100 μg mL−1) showed negative effect on bacteria as well as plant. Growth, morphology, survival, cellular respiration and inner membrane permeability of Sinorhizobium saheli was hampered when exposed to pesticides. Pesticide induced morphological changes viz. aberrant margins; cellular cracking and distortion/damage in S. saheli were obvious under scanning electron microscope (SEM). The 100 μgCBNmL−1 had maximum inhibitory effect and it reduced survivability of S. saheli by 75%. In addition, biofilm formation ability of S. saheli was inhibited in a pesticides-dose dependent manner and it was statistically (p ≤ 0.05) significant. Pesticides indorsed significant changes in biomarker enzymatic assays and oxidative stress parameters towards S. saheli. Furthermore, at 100 μgCBNmL−1, germination efficiency, root, shoot length, plant survival and tolerance index of V. mungo were decrease by 50, 75, 65, 70 and 66%, respectively over control. Staining of pesticide treated roots with fluorescently labeled dyes propidium iodide (PI) and acridine orange (AO) showed increased oxidative stress, ROS generation and membrane permeability as revealed under confocal laser scanning microscope (CLSM). Furthermore, stressor metabolites and antioxidant enzymes in plant seedlings were progressively enhanced with increasing concentration of pesticides. Conclusively, present finding bestow an insights into a mechanistic approach of carbamate pesticide induced phyto, morpho and cellular toxic effects towards soil bacterium as well as plant with forthcoming implications for designing the pesticides to reduce their toxic/harmful effects.

Camptothetin (CPT) is a quinoline alkaloid originally isolated from the Chinese tree, Camptotheca acuminata Decne. CPT was found to have anticancerous and antiviral properties. Derivatives of natural CPT, including topothecan and irinotecan are used clinically to treat a variety of cancers. Apart from Camptotheca acuminata Decne, CPT production was also found in the perennial plant Ophiorrhiza mungos. In this study we attempted the immobilization of the tissue culture grown callus of Ophiorrhiza mungos for the continuous production of a higher concentration of CPT. As evident from previous studies about the antiviral effects of CPT, we wanted to bioinformatically analyze the binding potential of CPT towards two important proteins of SARS-CoV-2, protease (Mpro) and RNA dependent RNA polymerase (RdRp). Further docking analysis of the CPT against the exterior spike glycoprotein of SARS-CoV-2 was also done to determine their potential interaction. The immobilized callus of Ophiorrhiza mungos produced CPT at a concentration of 420 µg/l by the end of 12 days of growth. The HPLC analysis was done to determine the purity of the CPT synthesized by the immobilization technique. The bioinformatic analysis revealed a higher binding efficiency of CPT and its derivatives, toptecan and irinotecan against Mpro and RdRp. The docking analysis of CPT against the spike glycoprotein of SARS-CoV-2 showed hydrogen bonding with the amino acids at K466 with a bond distance of 2.56A° and K355 with a bond distance of 2.40A°. This finding was of particular importance that other compounds including hydroxychloroquine sulphate, lopinavir and ivermectin could bind with the spike protein only by weak Vander wall bonds and no hydrogen bond formation was noticed. Our studies hence evaluate the efficiency of CPT against SARS-CoV-2, by potentially blocking the interaction of the spike glycoprotein with the angiotensin-converting enzyme 2 (ACE2) receptor found on host cells.