Pharmacological studies on Buchanania lanzan Spreng.-A focus on wound healing with particular reference to anti-biofilm properties

Objective:To evaluate the wound healing activity of the methanolic root extract of Buchanania lanzan Spreng. (B. lanzan), with a focus on antimicrobial and anti-biofilm properties. Methods: The extract was evaluated for its wound healing properties (excision and incision models) as evident from the analysis of tensile strength and wound contraction. The extract was also screened for antibacterial properties against different Gram positive and Gram negative bacterial strains. B. lanzan was also studied for its effect on biofilm formation and disruption of preformed biofilms. The synergistic effect of B. lanzan was determined in combination with gentamicin. Results:Topical application of B. lanzan (10%w/w ointment) significantly increased (40.84%) the tensile strength in the incision wound model. B. lanzan also showed significant wound healing activity in excision model and such significant activity was observed from the 9th day. Whereas Soframycin displayed significant wound healing activity from the 6th day. It was found that root extracts of B. lanzan revealed significant inhibition against all tested pathogens. B. lanzan displayed antimicrobial activity against Gram positive (MIC 0.625 mg/mL) and Gram negative (MIC 0.625-1.25 mg/mL). B. lanzan was able to reduce biofilm formation and also caused disruption of preformed biofilms in a manner similar to ciprofloxacin. However, gentamicin was found to be ineffective against biofilms formed by Gram negative organism. According to the fractional inhibitory concentration index, B. lanzan displayed synergistic activity when it was combined with gentamicin. Conclusions:From this study it may be concluded that the root extract of B. lanzan revealed significant wound healing potential, which was supported and well correlated with pronounced antibacterial activity of the tested plant parts.

Effect of Mesua ferrea Linn. flower extract on Salmonella.

Based on its traditional uses in folk medicine, the whole flower extract of Mesua ferrea Linn. was tested for its in vitro antimicrobial efficacy against five different strains of Salmonella spp. All the strains were found to be highly sensitive to the extract, MIC of the extract against each organism being 50 microg/ml. The extract was tested in vitro for its mode of antibacterial activity against S. Typhimurium NCTC 74 and it was found to be bactericidal in action. In vivo studies of this extract offered significant protection to Swiss albino mice at doses approximately 2 and 4 mg/mouse when challenged with 50 median lethal dose of S. Typhimurium NCTC 74. Further, the extract caused statistically significant reduction in viable count of the strain in liver, spleen and heart blood of challenged mice.

Antimicrobial potentiality of a phenothiazine group of antipsychotic drug-prochlorperazine.

The antipsychotic drug, prochlorperazine (Pcp), was tested for its antimicrobial efficacy against 103 strains belonging to both gram positive and gram negative bacteria. The drug was found to possess maximum activity against Staphylococcus aureus, Vibrio cholerae and Shigella spp. Pcp was moderately active against E. coli but most of the strains belonging to Bacillus spp, Klebsiella spp, Salmonella spp and Lactobacillus spp were found to be resistant to this drug. The drug was tested for its mode of antibacterial activity against Shigella dysenteriae 1 and it was found to be bacteriostatic in action. In in vivo studies, Pcp offered significant protection to Swiss albino mice at concentrations of 0.75 micro g/g (P < 0.01) and 1.5 microg/g (P < 0.001) body weight when challenged with 50 median lethal dose of Salmonella typhimurium NCTC 74. Thus the result depicts that prochlorperazine may emerge as a strong antimicrobial drug to replace the conventional antibiotics and to overcome the problem of drug resistance.