The release of untreated tannery effluents comprising biotoxic heavy metal (HM) compounds into the ecosystem is one of our society’s most serious environmental and health issues. After discharge, HM-containing industrial effluents reach agricultural soils and thus negatively affect the soil microbial diversity. Considering these, we assessed the effect of HMs on identified soil beneficial bacteria. Here, the effects of four heavy metals (HMs), viz., chromium (Cr), cadmium (Cd), nickel (Ni), and lead (Pb), on cellular growth, physiology, cell permeability, and biofilm formation of Enterobacter cloacae MC9 (accession no.: MT672587) were evaluated. HMs in a concentration range of 25–200 μg mL–1 were used throughout the study. Among HMs, Cd in general had the maximum detrimental effect on bacterial physiology. With increasing concentrations of HMs, bacterial activities consistently decreased. For instance, 200 μgCr mL–1 concentration greatly and significantly (p ≤ 0.05) reduced the synthesis of indole-3-acetic acid (IAA) by 70% over control. Furthermore, 200 μg mL–1 Cd maximally and significantly (p ≤ 0.05) reduced the synthesis of 2,3-dihydroxybenzoic acid (2,3-DHBA), salicylic acid (SA), 1-aminocyclopropane 1-carboxylate (ACC) deaminase, and extra polymeric substances (EPSs) of E. cloacae MC9 by 80, 81, 77, and 59%, respectively, over control. While assessing the toxic effect of HMs on the P-solubilizing activity of E. cloacae, the toxicity pattern followed the order Cr (mean value = 94.6 μg mL–1) > Cd (mean value = 127.2 μg mL–1) > Pb (mean value = 132.4 μg mL–1) > Ni (mean value = 140.4 μg mL–1). Furthermore, the colony-forming unit (CFU) count (Log10) of strain MC9 was completely inhibited at 150, 175, and 200 μg mL–1 concentrations of Cr and Cd. The confocal laser scanning microscopic (CLSM) analysis of HM-treated bacterial cells showed an increased number of red-colored dead cells as the concentration of HMs increased from 25 to 200 μg mL–1. Likewise, the biofilm formation ability of strain MC9 was maximally (p ≤ 0.05) inhibited at higher concentrations of Cd. In summary, the present investigation undoubtedly suggests that E. cloacae strain MC9 recovered from the HM-contaminated rhizosphere endowed with multiple activities could play an important role in agricultural practices to augment crop productivity in soils contaminated with HMs. Also, there is an urgent need to control the direct discharge of industrial waste into running water to minimize heavy metal pollution. Furthermore, before the application of HMs in agricultural fields, their appropriate field dosages must be carefully monitored.

No abstract

In pursuit of new antitubercular agents, we here report the antimycobacterial (H 37 Rv) and DNA gyrase inhibitory potential of daidzein and khellin natural products (NPs). We procured a total of 16 NPs based on their pharmacophoric similarities with known antimycobacterial compounds. The H 37 Rv strain of M. tuberculosis was found to be susceptible to only two out of the 16 NPs procured; specifically, daidzein and khellin each exhibited an MIC of 25 μg/mL. Moreover, daidzein and khellin inhibited the DNA gyrase enzyme with IC 50 values of 0.042 and 0.822 μg/mL, respectively, compared to ciprofloxacin with an IC 50 value of 0.018 μg/mL. Daidzein and khellin were found to have lower toxicity toward the vero cell line, with IC 50 values of 160.81 and 300.23 μg/mL, respectively. Further, molecular docking study and MD simulation of daidzein indicated that it remained stable inside the cavity of DNA GyrB domain for 100 ns.

Introduction: The area of “Green Synthesis of Nano-medicine,” as compared to its synthetic counterparts, is a relatively safer research technology for various biomedical applications, including identification, therapeutic application, and prevention of pathological conditions, pain control, safety, and development of human wellness. The present study explored the synthesis and characterization of AgNPs using the ethanolic extract of Piper cubeba fruit as a reducing and stabilizing agent and its potential as an enzyme inhibitory agent. Urease inhibitors are helpful against many severe diseases, including gastric ulcers induced by Helicobacter pylori.Method: The fruits of the Piper cubeba plant were taken and ground to a fine powder. Plant material was added to 500 ml ethanol, and the mixture was filtered. The solvent of the filtrate was evaporated, and a thick, gummy extract was obtained and stored at 4°C in the refrigerator. AgNPs were green synthesized from solutions of AgNO3 using the P. cubeba extract, which was indicated by a change in the color from light brown to deep brown. The synthesized AgNPs were characterized via Ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM).Results and Discussion: Analysis showed the reduction of Ag+ to Ag0 at room temperature (25°C), and the average particle size of AgNPs was in the range of 40–80 nm. Consequently, the synthesized AgNPs were evaluated for their anti-urease activity. The maximum urease inhibition of the Piper cubeba ethanolic extract was 88.5% at 5 mg conc., and of derived nanoparticles was 78.6% at 0.05 mg conc. The results were nearly similar to the control drug, i.e., thiourea (0.5 and 0.6 mM conc., respectively).Conclusion: The study concluded that the P. cubeba extract, as well as its green-derived AgNPs, might prove to be a better and safer substitute for their enzyme inhibitory potential in emerging medicine and novel drug delivery techniques to improve and maintain human health.

Purpose: A HPLC method for Fingolimod was developed using a Quality by Design concept. QbD has gained importance in recent times due to regulatory requirements. Actual study was started after determination of target profile and qualification of instrument. Methods: Separation was carried on a Grace C-8 column (4.6 x 250 mm, 5-μm particle size).The composition of mobile phase was methanol and 20 mM ammonium formate buffer of pH5.8 in gradient mode HPLC method development is affected by critical factors like pH, flow rate and mobile phase composition. Results: To study the effects of these three factors on USP tailing, Box Behnken optimization model was applied. Desirability of the model was set at Tailing less than 1.2.Analysis of results was done using surface diagrams. Verification of Software generated results was done by taking six replicates of the run. Thus developed and optimised method was Finally validated as per ICH guideline. Conclusion: A Quality by Design approach has been successfully utilised in method development of the Fingolimod in bulk. All key aspect of QbD were tried to be implemented in said study. Systematic approach was utilized for method development which includes beginning with determination of target profile characteristics, instrument qualification, risk assessment, design of experiment and validation. Three factors i.e. Ph, flow rate and methanol concentration were analysed for their effect on USP tailing as a responce. Interaction and quadratic effect of the factors were studied with least possible runs by using Box Behnken model. Response surface diagrams and contour plots were studied for coming to conclusion which factors are affecting response and their limits were recorded. Optimum run condition was obtained; Replicates of run having optimized condition were taken to confirm the predicted response with actual response.