In-vitro antileptospiral activity of Canarium odontophyllum Miq. (Dabai) leaves extract

Aims@#To evaluate the anti-leptospiral activity of Canarium odontophyllum leaves against Leptospira interrogans serovar Bataviae and Leptospira borgpetersenii serovar Javanica. @*Methodology and results@#The extracts (hexane, acetone, methanol and aqueous) used in this study were tested at concentration ranging from 0.049 mg/mL to 25 mg/mL using broth microdilution method. Percentage inhibition (%) was obtained through OD reading at 400 nm. Only methanol extract was incubated with Leptospira to observe population changes under dark field microscope prior to subjected for DNA damaging studies through gel electrophoresis of genomic DNA. Methanol extract showed the highest percentage inhibition of 66% against L.interrogans serovar Bataviae and 74% against L. borgpetersenii serovar Javanica. The IC50 value of methanol extract was 4.60 mg/mL and 2.25 mg/mL against serovar Bataviae and serovar Javanica, respectively. Both Leptospira culture which was treated with IC50 value of methanol extract showed drastic decrease in population compared to untreated Leptospira for both serovar. There was no DNA damage towards serovar Bataviae. However, serovar Javanica exhibited DNA damage as observed from the presence of DNA fragmentation on the gel electrophoresis. @*Conclusion, significance and impact of study@#These findings confirmed that methanol leaves extract from of Canarium odontophyllum has a potential to control leptospirosis.

An assessment of the acetone extract from the leaves of Canarium odontophyllum (Miq.) for antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA)

Abstract@#Methicillin-resistant Staphylococcus aureus (MRSA) causes nosocomial and community infections and is a global health concern. This study evaluated the antibacterial activity of acetone extract from Canarium odontophyllum leaves against MRSA ATCC 33591 and Mu50 strains. The MIC/MBC ratio, determined using the broth micro dilution method, revealed the bacteriostatic effect of the extract against both strains. Time-kill assay against the Mu50 strain showed that the extract inhibited the growth of MRSA at low concentration but exhibited a concentration-dependent bacterial killing effect at 4× MIC. These findings confirm that an acetone extract from C. odontophyllum leaves inhibited growth of MRSA at low concentrations and could be utilised as an alternative anti-MRSA agent.

Stem Bark of Canarium odontophyllum Miq. (Dabai) as Potential Source of Antimicrobial Agent / Jurnal Sains Kesihatan Malaysia

The objective of this study was to evaluate the antimicrobial potential of methanol, acetone and distilled water stem bark extracts from Canarium odontophyllum against Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 6633, Escherichia coli ATCC 25932, Pseudomonas aeruginosa ATCC 27853, Acinetobacter baumannii strain sensitive, Candida albicans ATCC 64677, Candida glabrata ATCC 90028, Aspergillus niger and Fusarium solani M2781. The extracts from C. odontophyllum stem bark from 3.125 mg/ml to 25 mg/ml were screened against the tested microorganisms using disc diffusion method. The Minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts against susceptible organisms were determined using microbroth dilution method and streak-plate technique, respectively. From the antibacterial screening assay, the growth of S. aureus, B. cereus and A. baumannii were inhibited by methanol extract whereas the acetone extract was capable of inhibiting all the tested microorganisms except E.coli, F. solani and A. niger. The lowest MIC value for methanol extract was against A. baumannii (0.195 mg/ml) whereas its MBC value was twice its MIC value (0.391 mg/ml), indicating that methanol extract was bacteriostatic against A. baumannii. While for acetone extract, S. aureus showed bactericidal effect with equal MIC and MBC values at 0.195 mg/ml. In conclusion, stem bark of C. odontophyllum has the potential to be the source of antibacterial agent and can be exploited as an alternative phytoantimicrobial.

Synergy of flavone with vancomycin and oxacillin against vancomycin-intermediate Staphylococcus aureus

This study evaluated in vitro activity of 9 flavonoids in combination with vancomycin or oxacillin against vancomycin-intermediate Staphylococcus aureus [VISA] ATCC 700699 by employing the checkerboard method to obtain Minimal inhibitory concentration [MIC] and fractional inhibitory concentration [FIC] index. Six flavonoids namely hesperitin, rutin, naringenin, flavones, naringin and 3, 7-dihyroxyflavone which exhibited notable inhibitory activity [MIC values 4] were observed. In time kill studies, oxacillin-flavone combination at synergistic concentration demonstrated bactericidal effect at 24 h period with concentration-dependent manner on the VISA strain. Following 1 h exposure, the combination also produced persistent effect on the bacteria growth for 2.9 hrs at 1x sub-MIC and more than 24 h at 5x of sub-MIC and there was a significant difference between both concentrations [p<0.05]. Vancomycin-flavone combination, however, showed no concentration-dependant effect and lower PAE values [1.159 h and 2.322 h at 1x and 5x sub-MIC, respectively] on the VISA strain. In conclusion, flavone markedly intensifies the susceptibility of oxacillin against VISA and the combination can be implicated for further interaction studies at molecular level