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 Henna (Lawsonia inermis) Leaf Extracts (Chloroform) Against Two Food Borne and Nosocomial Infection Causing Pathogens: Staphylococcus aureus and Escherichia coli.

Evaluation of the in vitro antibacterial activity of Chloroform extracts isolated from Henna (Lawsonia inermis) leaf against two food born & nosocomial infection causing pathogens, gram-positive Staphylococcus aureus and gram-negative Escherichia coli. This interventional study was carried out during 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, Mymensingh, 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% 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 1000mg/ml) and later in selected concentrations as needed to confirm the more precise margin of antimicrobial sensitivity of the extracts. Among different concentrations of the CHE, 100mg/ml and above concentrations showed inhibitory effect against Staphylococcus aureus and 300mg/ml and above concentrations showed inhibitory effect against Escherichia coli. The MIC for Staphylococcus aureus and Escherichia coli were 100 and 350mg/ml in CHE respectively. The MIC of Ciprofloxacin was 1µg/ml against both Staphylococcus aureus and Escherichia coli. The MIC of Ciprofloxacin was the lowest in comparison to MICs of CHE for the test organisms. The present study showed that Chloroform Henna extracts demonstrated antibacterial effects against food borne pathogens. From this study, it is clearly observed that there is definite antibacterial effect of the chloroform extract of Henna leaves against Staphylococcus aureus and Escherichia coli.

Antibacterial Effect of Curcuma longa (Turmeric) Against Staphylococcus aureus and Escherichia coli.

This observational study was conducted during the period from July 2010 to June 2011 in the Department of Pharmacology in the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh to determine the profile of antibacterial effect of Crude Turmeric paste aqueous turmeric extract, and standard antibiotic Amikacin against Staphylococcus aureus and Escherichia coli. Three separate experiments were done e.g. (Expt- I) Inhibitory effect of Crude Turmeric paste incorporated into nutrient agar (NA) media, (Expt- II) Minimum inhibitory concentration of (a) Aqueous Turmeric extract and (b) Amikacin by broth dilution technique and (Expt-III) their subculture study in nutrient agar (NA) media for confirmation of respective results of previous experiments. Inhibitory effects were observed against the growth of Staph Aureus and Esch coli at 10% and 30% respectively of Crude Turmeric paste incorporated into NA media. The broth dilution technique was followed to determine the MIC of Aqueous Turmeric extract and Amikacin. The MIC of Aqueous Turmeric extract was 800 µg/ml against Staph aureus and that against Esch coli was 2000 µg/ml and the MIC of Amikacin was 10 µg/ml for both the bacteria. The MIC of Amikacin was the lowest in comparison to MIC of Aqueous Turmeric extract for complete inhibition of growth of Staph aureus and Esch coli. The subculture study showed similar results with that of previous experiments in terms of inhibitory effects of Crude Turmeric paste and MIC of Aqueous Turmeric extract and Amikacin against all of the organisms studied.

Hypoglycemic effect of Catharanthus roseus in normal and streptozotocin-induced diabetic rats.

The effects of crude juice (at 0.5 and 1 ml/kg b.w.) and aqueous extract (at 0.30 and 0.45 gm/kg b.w.) of leaves of Catharanthus roseus on serum glucose level in streptozotocin induced diabetic rats were examined at 8 hours, 12 hours and 24 hours following single oral administration. The administration of crude juice at 1 ml/kg b.w. continued for another 9 doses (total 10 single morning doses given) and its effect was examined on the 4th and 11th day. The rats were made diabetic by single intraperitoneal injection of streptozotocin at 45 mg/kg b.w. Glibenclamide was used in the study for comparison. The crude leaf juice at 0.5 and 1 ml/kg b.w. reduced the serum glucose level in streptozotocin induced diabetic rats throughout the 24-hour period significantly (P varies between 0.05 and 0.001 at different times). The aqueous extract at 0.30 and 0.45 gm/kg reduced the serum glucose level in streptozotocin diabetic rats at 8 and 12 hour significantly (P varies between 0.05 to 0.01 at different times) but not at the 24 hour. Glibenclamide, at 500 mug/kg, also reduced the serum glucose level in streptozotocin induced diabetic rats throughout the 24-hour period (P<0.001). The crude leaf juice at 1 ml/kg also significantly reduced the serum glucose level in the streptozotocin induced diabetic rats on the 4th and 11th day (P<0.001 on both occasions). The effect of crude leaf juice at 1 ml/kg b.w administered daily orally over a 10 day period was also examined on a group of normal rats at different times. The study showed significant reduction at 8 hr (P<0.05), 12 hr, 24 hr and on the 4th day (P<0.01 on these 3 occasions) and also on the 11th day (P<0.001).