Antimicrobial Susceptibility Patterns Of Bacteria To Seed Extracts Of Ricinus Communis: Findings Of A Preliminary Study In Nigeria
G Jombo, M Enenebeaku
antimicrobial susceptibility, seed extracts
G Jombo, M Enenebeaku. Antimicrobial Susceptibility Patterns Of Bacteria To Seed Extracts Of Ricinus Communis: Findings Of A Preliminary Study In Nigeria. The Internet Journal of Microbiology. 2006 Volume 4 Number 1.
Several biophysical properties have been associated with
From the microbiological stand point, there has not been much published data on
In view of the fact that bacteria have assumed an unprecedented level of antimicrobial resistance more than ever in the history of modern medicine24,25,26,27; the continuous search for more reliable antibiotics becomes a worthwhile and noble mission. This study was therefore set up to ascertain the antibacterial properties of the seed extracts of
Materials And Method
Setting The study was carried out in Jos Plateau state of Nigeria between August and November 2005.
Seed Preparation Seeds of
Soxhlet Extraction The solvent used was absolute methanol. Twenty grams of the ground dry sample of the seed was placed in an extracting thimble and placed in the soxhlet apparatus. A water condenser was attached to the soxhlet apparatus at the top. The apparatus was fitted into the neck of a flask containing 250mls of the methanol (solvent) heated on a water bath.
The vapour from the solvent reached the soxhlet apparatus through the side tube and condensed on passing into the condenser. The condensed solvent dropped on the crude substance in the thimble and dissolved the required substance. The solution filtered through the thimble into the flask bearing the solvent. This process continued until the solvent from the thimble was colourless. Extraction was then said to be completed. This continuous extraction method extracted all the components of the plant which were soluble in methanol. The extract was then evaporated to dryness and a light brown oily extract was collected, weighed and stored by refrigeration at temperature of 40C for further susceptibility testing. Similar procedure was carried out for water extraction where water was used in place of methanol.
Antimicrobial Susceptibility Testing Bacteria used for the study were obtained from the Microbiology laboratory of the Jos University Teaching Hospital (JUTH), Jos. Organisms tested were:
The preparation was incubated overnight at 370C and the diameters (in millimeters) of zones of inhibition were measured using vernier calipers28.
Interpretation of Results The sensitivity report was interpreted as Sensitive (S), Intermediate (I) and Resistant (R) as follows:
Sensitive (S) Zone radius of inhibition wider than, equal to, or not more than 3mm smaller than the positive control.
Intermediate (I) Zone radius of inhibition is more than 3mm smaller than the positive control but not less than 3mm.
Resistant (R) No zone of inhibition or zone radius measures 2mm or less.
All the organisms tested were Resistant to both the methanol and water extracts at 5mg/ml concentrations except
For the 7mg/ml concentrations,
Most of the organisms were Intermediate to Sensitive for the 8mg/ml extracts of both methanol and water except
Both the methanol and water extracts at 9mg/ml strengths of the extracts were Intermediate to Sensitive against all the organisms tested, while the 10mg/ml of both extracts were Sensitive against all except the water extracts against
Generally, all the bacteria tested (
The active antibacterial ingredients in the Castor seed extracts should be identified and processed in possibly commercial quantities in order to seek its relevance in the current war against antimicrobial resistance. This no doubt poses a serious challenge to the modern day practice of medicine29,30,31,32. The fact that treatment of infections caused by organisms such as
Further work should be carried out to identify the active ingredients with the antibacterial properties as well as the tolerable human dose range vis-à-vis the minimum inhibitory concentration (MIC).
In conclusion, seed extracts of
JOMBO G T A Department of Medical Microbiology & Parasitology, College of Medical Sciences, University of Calabar, P M B 1115 Calabar, Nigeria. E.mail- firstname.lastname@example.org Tel-08039726398