ABSTRACT
Canarium odontophyllum Miq. is an indigenous fruit found in Sarawak, Malaysia. Methicillin-resistant Staphylococcusaureus (MRSA) is a deadly pathogen that causes to hospital (health-care-acquired MRSA [HA-MRSA]) and community(CA-MRSA) infections worldwide. Vancomycin has been the therapeutic drug of choice against MRSA, but unfortunatelythis pathogen has developed some degree of resistance to vancomycin. This research aimed to evaluate the antimicrobialactivity of the stem bark extract of C. odontophyllum against MRSA Mu50 strain. The minimum inhibitory concentration(MIC) and minimum bactericidal concentration (MBC) of extract and vancomycin against MRSA were determined usingbroth microdilution method and streak plate method. The rate of killing by the extract against Mu50 strain was determinedusing time-kill assay (TKA) at ×1 MIC, ×2 MIC, ×4 MIC, and ×8 MIC of the extract. The post-antibiotic effect (PAE) timeof extract ×10 MIC against MRSA was also investigated. The extract exhibited bacteriostatic effect against MRSA Mu50strain with MIC and MBC values of 1.563 mg/ml and 3.125 mg/ml, respectively. From TKA analysis, the extract was notcapable of killing the Mu50 strain at ×1 MIC and ×2 MIC, but it displayed bactericidal activity at higher concentrationstested. Interestingly, the acetone stem bark extract of C. odontophyllum at ×4 MIC showed comparable time-killingkinetic with the standard antibiotic in the study. The PAE time of the extract was 3.6 ± 0.51 h against MRSA Mu50compared to vancomycin at 2.4 ± 0.68 h. In conclusion, the stem bark acetone extract from C. odontophyllum demonstratedconcentration-dependent bactericidal effect with prolonged PAE time against MRSA Mu50 strain.
ABSTRACT
@#Introduction: Different solvents extraction was used to extract the good fatty acid composition of Dabai fruits. Nevertheless, solvents extraction may exhibit harmful effects. The present study was aimed to evaluate the safety of using supercritical carbon dioxide extraction (SCO2) of dabai pulp oil by acute toxicity study in Specific Pathogen Free (SPF) Sprague-Dawley (SD) rats. Methods: The CO pulp oil extract was prepared by SCO2 extraction of the freezedried pulp and was administered orally to SPF SD rats (consisted of 5 rats/sex/group) at upper limit dose 5000 mg/kg body weight (BW) for 14 days. The study includes the control and treatment groups, each consisting of 5 male and female rats. The rats were fed and allowed to drink sterilized water ad libitum. Fatty acid composition (FAC) of the extract was determined using GC-FID. Electrolytes and biochemical parameters in blood, as well as relative organs weight were measured. Results: The extract at a single dose of 5000 mg/kg did not cause any acute toxicity effects or mortality to the treatment of rats during observation periods in 14 days. FAC of the SCO2 extracted oil exhibited high content of palmitic and linoleic acids. The relative organs weights (ROW) and histopathology of rats were within normal range. Conclusion: Thus, the LD50 was estimated to be more than 5000 mg/kg of CO pulp oil extract and can be considered for further investigation for its therapeutic efficacy in a larger animal model
Subject(s)
Toxicity Tests, AcuteABSTRACT
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.
ABSTRACT
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.