Studies on the effect of ethanolic extract of propolis in BALB/c mice

Propolis is widely used since ages for the treatment of various ailments. Present study focussed on the toxicity profile of ethanolic extract of propolis on BALB/c mice. The effect of different concentrations of propolis (300, 500, 1000 mg/kg body weight) was analysed by studying the biochemical, haematological and histological changes in mice for 28 days. No significant difference in various parameters were observed in groups of mice treated with propolis and the normal control (p>0.05). Histological findings on liver, spleen, kidney and brain revealed normal architecture. The ethanolic extract of propolis did not produce significant toxic effect in mice and hence can be utilized for nutraceuticals formulations

Efficacy of different extracts of propolis against Salmonella enterica serovar Typhimurium: In vitro and in vivo study

Present study focussed on the antibacterial and antioxidative effect of honey bee propolis on typhoid causing bacteria i.e. Salmonella. Water, ethanol, methanol were used as solvents for making of extracts. Both Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were calculated for all the three extracts. MIC of ethanolic extract of propolis was 160 mg/ml. It was 200 mg/ml for methanolic and 220mg/ml for wa-ter extracts respectively. Moreover, time kill analysis results confirmed that there was a significant reduction (p<0.05) in log count of bacteria when treated with ethanolic extraxt of propolis (3.98±0.15 log cfu/mL) and methanolic (4.66±0.05log cfu/mL) extract of propolis as compared to Salmonella control (7.72±0.03 log cfu/mL) in in vitro experiments. For the in vivo studies, BALB/c mice was used as an murine model of typhoid. Levels of different liver marker enzymes and antioxidants like Lipid peroxidation (LPO) and Reduced Glutathione (GSH) were observed in infected and all the treated groups. By comparing the results, it was concluded that ethanolic extract of propolis showed maximum antimicrobial activity as compare to the rest two. So the results of present study encourages the potential of ethanolic extract of propolis as an alternative treatment for typhoid and its use in combination with standard antibiotics can also be explored

Evaluation of interleukin-10 production in Pseudomonas aeruginosa induced acute pyelonephritis

SummaryPseudomonas aeruginosa is an opportunistic pathogen of immunocompromised hosts. This pathogen has a tendency to form biofilms on the surface of indwelling catheters leading to acute and chronic urinary tract infections that result in significant morbidity and mortality. In the present study, kinetics of interleukin-10 (IL-10) production in mouse renal tissue was studied employing experimental mouse model of acute pyelonephritis induced with planktonic and biofilm cells of P. aeruginosa. IL-10 production was found to be significantly lower in biofilm cell instilled mice compared to planktonic cell infected animals, which corroborated with higher bacterial load and tissue damage. The data suggests that downregulation of IL-10 production may be novel strategy employed by biofilm cells to cause tissue damage and hence bacterial persistence. The results of the present study may open up avenues of research that will ultimately provide the foundation for the development of preventative measures and therapeutic strategies to successfully treat P. aeruginosa biofilm infections based on the administration of anti-inflammatory agents

Preliminary studies on different extracts of some honey bee products

The aim of present study was to compare the phytochemical composition of different extracts of bee pollen, propolis and honey and to analyse the best solvent for maximum phytochemicals extraction. These preliminary studies are significant in locating the pharmacological bioactive compounds in different extracts of bee products. The tests showed greater number of constituents present in bee pollen and propolis as compared to honey. The concentration of these bioactive constituents was greater in ethanolic extract of propolis and water extract of bee pollen and honey. Ethanolic extract of propolis showed higher concentration of tannins and glycosides. Bee pollen had more concentration of saponins, flavonoids and proteins in water extract. Reducing sugars and carbohydrates were present in larger amount in water extract of honey. These studies will be useful to select the best solvent for honey, pollen and propolis for various research purposes

Targeting envelope proteins of poxviruses to repurpose phytochemicals against monkeypox: An in silico investigation

The monkeypox virus (MPXV) has become a major threat due to the increasing global caseload and the ongoing multi-country outbreak in non-endemic territories. Due to limited research in this avenue and the lack of intervention strategies, the present study was aimed to virtually screen bioactive phytochemicals against envelope proteins of MPXV via rigorous computational approaches. Molecular docking, molecular dynamic (MD) simulations, and MM/PBSA analysis were used to investigate the binding affinity of 12 phytochemicals against three envelope proteins of MPXV, viz., D13, A26, and H3. Silibinin, oleanolic acid, and ursolic acid were computationally identified as potential phytochemicals that showed strong binding affinity toward all the tested structural proteins of MPXV through molecular docking. The stability of the docked complexes was also confirmed by MD simulations and MM/PBSA calculations. Results from the iMODS server also complemented the findings from molecular docking and MD simulations. ADME analysis also computationally confirmed the drug-like properties of the phytochemicals, thereby asserting their suitability for consumption. Hence, this study envisions the candidature of bioactive phytochemicals as promising inhibitors against the envelope proteins of the MPXV, serving as template molecules that could further be experimentally evaluated for their efficacy against monkeypox

Acyl Homoserine Lactones from Culture Supernatants of Pseudomonas aeruginosa Accelerate Host Immunomodulation

The virulence of Pseudomonas aeruginosa is multifactorial and under the control of quorum sensing signals, such as acyl homoserine lactones (AHLs). The importance of these molecules in the establishment of infection has been previously reported. These molecules either improve the virulence potential of P. aeruginosa or modulate the host immune response. To establish the immune modulating potential of quorum sensing signal molecules, previous studies have only used synthetic AHLs. However, there can be differences in the biological properties of synthetic and natural AHLs. The use of naturally extracted AHLs from the culture supernatant of P. aeruginosa is likely to simulate natural conditions more than the use of synthetic AHLs. Therefore, in the present study, the immune modulating potential of synthetic and naturally extracted AHLs was compared using a thymidine uptake assay, immunophenotyping and sandwich ELISA in order to assess mouse T-cell proliferation and production of Th1 and Th2 cytokines. Natural AHLs were able to suppress T-cell proliferation, even at low concentrations, compared to synthetic AHLs. The majority of cells undergoing proliferation were CD4+, as revealed by immunophenotyping. The inhibition of T-cells was stronger with natural AHLs compared to synthetic AHLs. Moreover, the natural AHLs were also able to shift immune responses away from host protective Th1 responses to pathogen protective Th2 responses

Bacteriophage mediated killing of Staphylococcus aureus in vitro on orthopaedic K wires in presence of linezolid prevents implant colonization.

BACKGROUND: Infections of bone and joint tissues following arthroplasty surgeries remain a major challenge in orthopaedic settings. Methicillin resistant Staphylococcus aureus (MRSA) is recognised as an established pathogen in such infections. Combination therapy using linezolid and bacteriophage impregnated in biopolymer was investigated in the present study as an alternative strategy to prevent MRSA colonisation on the orthopaedic implant surface. METHODOLOGY: Coating of stainless steel orthopaedic grade K-wires was achieved using hydroxypropylmethlycellulose (HPMC) mixed with phage alone, linezolid alone and phage and linezolid together. The potential of these agents to inhibit adhesion of S.aureus (MRSA) 43300 on K-wires was assessed. Coated and naked wires were analysed by scanning electron microscopy (SEM) and fluorescent staining. RESULT: Significant reduction in bacterial adhesion was achieved on phage/linezolid wires in comparison to naked as well as HPMC coated wires. However, maximum reduction in bacterial adherence (∼4 log cycles) was observed on the wires coated with phage-linezolid combination. The frequency of emergence of resistant mutants was also negligible in presence of both the agents. CONCLUSION: This study provides evidence to confirm that local delivery system employing linezolid (a potent protein synthesis inhibitor) along with a broad spectrum lytic bacteriophage (capable of self-multiplication) is able to attack the adhered as well as surrounding bacteria present near the implant site. Unlike other antibiotic based therapies, this combination has the potential to significantly restrict the emergence of resistant mutants, thus paving the way for effective treatment of MRSA associated infection of medical implants