Antibacterial Activities of Methanolic Seeds Extract of Black pepper (Piper nigrum L.) against Gram Positive Staphylococcus aureus & Gram-Negative Escherichia coli.

Evaluation of the in vitro antibacterial activity of Methanolic extracts isolated from Black pepper seeds (Piper nigrum L.) against two infection causing pathogens, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Between July 2022 and June 2023, this experimental study was conducted at the Mymensingh Medical College's Department of Pharmacology and Therapeutics in conjunction with the Department of Microbiology. Using the disc diffusion and broth dilution methods, the antibacterial activity of methanolic extract of black pepper seeds (MBPE) was evaluated at various doses. The solvents Methanol and 10.0% Di Methyl Sulfoxide (DMSO) were used to make the extract. Using the broth dilution procedure, the conventional antibiotic Ciprofloxacin was utilized and the outcome was contrasted with that of Methanol extracts. Methanolic extract of black pepper seeds (MBPE) at seven distinct concentrations (100, 80, 60, 40, 20, 10 and 5 mg/ml) were utilized, then later in chosen concentrations as needed to confirm the extracts' more precise margin of antimicrobial sensitivity. At 80 mg/ml and above doses of the MBPE, it had an inhibitory impact against the aforementioned microorganisms. For Staphylococcus aureus and Escherichia coli the MIC were 60 and 75 mg/ml in MBPE respectively. As of the MIC of Ciprofloxacin was 1µg/ml against Staphylococcus aureus and Escherichia coli. In comparison to MICs of MBPE for the test organisms, the MIC of Ciprofloxacin was the lowest. This study clearly shows that Staphylococcus aureus and Escherichia coli are sensitive to the methanolic extract of black pepper seeds' antibacterial properties.

Antibacterial Effects of Chloroform Henna (Lawsonia inermis) Leaf Extracts against Two Nosocomial Infection Causing Pathogens: Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumoniae: A Comparative Study.

Evaluation of the in vitro antibacterial activity of Chloroform extracts isolated from Henna (Lawsonia inermis) leaf against two nosocomial infection causing pathogens, gram-positive Staphylococcus aureus and gram-negative Klebsiella pneumoniae. This interventional study was carried out for the period of January 2021 to December 2021 in the Department of Pharmacology and Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Bangladesh. The antibacterial activity was tested at different concentrations of Chloroform Henna leaf extracts by using disc diffusion and broth dilution method. The extract was prepared by using solvents chloroform and 0.1% Dimethyl sulfoxide (DMSO). The test microorganisms were also tested for their activity against a standard antibiotic Ciprofloxacin by broth dilution method and the result was compared with that of Chloroform extracts. Chloroform Henna Extracts (CHE) were used initially in nine different concentrations (2.5, 5, 10, 20, 50, 100, 200, 500 and 1000 mg/ml). Among different concentrations of the CHE, 100mg/ml and above concentrations showed inhibitory effect against Staphylococcus aureus and Klebsiella pneumoniae. The MIC for Staphylococcus aureus and Klebsiella pneumoniae were 100 and 200mg/ml in CHE respectively. The MIC of Ciprofloxacin was 1µg/ml against Staphylococcus aureus and 1.5µg/ml against Klebsiella pneumoniae. The MIC of Ciprofloxacin was the lowest in comparison to MICs of CHE for the test organisms. This study showed that Chloroform Henna extracts demonstrated antibacterial effects against food borne pathogens. It is clearly observed that there is definite antibacterial effect of the Chloroform extract of Henna leaves (Lawsonia inermis) against Staphylococcus aureus and Klebsiella pneumoniae.

Antibacterial Effect of Moringa (Moringa oleifera) Leaf Ethanolic Extract Against Staphylococcus aureus and Escherichia coli.

Increasing resistance of pathogenic microorganisms to synthetic antibiotics has lead to the search for alternative drug sources. In this regard, one of the reputed Medicinal plant, Moringa (Moringa oleifera) was investigated for potential antimicrobial effect against some commonly encountered bacteria such as Staphylococcus aureus, Escherichia coli. This experimental study was conducted from July 2019 to June 2020 in the Department of Pharmacology and Therapeutics in collaboration with the Department of Microbiology, Mymensingh Medical College, Bangladesh to determine the antibacterial effect of Ethanolic extract of Moringa oleifera leaf (EMLE) against aforementioned bacteria. The antibacterial activity was tested at different concentrations (100, 200, 400, 600, 800 and 1000µg/ml) of Ethanolic extract by using disc diffusion and broth dilution method. Dose dependent inhibitory effect was seen against the test organisms using disc diffusion method. The maximum zone of inhibition was 19 mm against S. aureus and 20mm against E. coli at 100.0% (1000µg/ml) concentration. The minimum inhibitory concentrations (MICs) of EMLE were 400µg/ml and 500µg/ml against Staphylococcus aureus and Escherichia coli respectively. The present study showed that Ethanolic extract of Moringa leaf demonstrated antibacterial effects against food borne pathogens. Further studies are required to detect and isolate the active ingredients present in the Moringa leaves extract responsible for its antibacterial effect.

Ferrous ion autoxidation and its chelation in iron-loaded human liver HepG2 cells.

Ferrous ion (Fe(2+)) is long thought to be the most likely active species, producing oxidants through interaction of Fe(2+) with oxygen (O(2)). Because current iron overload therapy uses only Fe(3+) chelators, such as desferrioxamine (DFO), we have tested a hypothesis that addition of a Fe(2+) chelator, 2,2'-dipyridyl (DP), may be more efficient and effective in preventing iron-induced oxidative damage in human liver HepG2 cells than DFO alone. Using ferrozine as an assay for iron measurement, levels of cellular iron in HepG2 cells treated with iron compounds correlated well with the extent of lipid peroxidation (r = 0.99 after log transformation). DP or DFO alone decreased levels of iron and lipid peroxidation in cells treated with iron. DFO + DP together had the most significant effect in preventing cells from lipid peroxidation but not as effective in decreasing overall iron levels in the cells. Using ESR spin trapping technique, we further tested factors that can affect oxidant-producing activity of Fe(2+) with dissolved O(2) in a cell-free system. Oxidant formation enhanced with increasing Fe(2+) concentrations and reached a maximum at 5 mM of Fe(2+). When the concentration of Fe(2+) was increased to 50 mM, the oxidant-producing activity of Fe(2+) sharply decreased to zero. The initial ratio of Fe(3+):Fe(2+) did not affect the oxidant producing activity of Fe(2+). However, an acidic pH (< 3.5) significantly slowed down the rate of the reaction. Our results suggest that reaction of Fe(2+) with O(2) is an important one for oxidant formation in biological system, and therefore, drugs capable of inhibiting redox activity of Fe(2+) should be considered in combination with a Fe(3+) chelator for iron overload chelation therapy.