University of Cape Coast, Ghana
OBJECTIVE: The study assessed anti-microbial activity of three extract fractions of Zanthoxylum zanthoxyloides leaf against three selected oral pathogens (Lactobacillus acidophilus, Aggregatibacter actinomycetemcomitans and Candida albicans).
RESULTS: The extract fractions produced concentration-dependent inhibition of growth. Except in the case of Lactobacillus acidophilus where growth inhibitory effect of the extract fractions was lower compared to standard antibiotic (ciprofloxacin), for the remaining pathogens, the extract fractions produced comparable growth inhibitory effects at lower (in the case of Candida albicans) and higher (in the case of Aggregatibacter actinomytemcomitans) concentrations relative to standard antibiotics (Amoxacillin & Metronidazole and Fluconazole). The extract fractions had varied MICs relative to vehicle (ethanol) and standard antibiotics with respect to the three oral pathogens. The extract fractions had higher MICs compared to control and standard antibiotic (ciprofloxacin) with respect to Lactobacillus acidophilus. However, except EEZZ the remaining extract fractions (PEEZZ and EAEZZ) had low MICs compared to control and standard antibiotics in the case of Aggregatibacter actinomycetemcomitans. In the case of Candida albicans, EEZZ had a lower MIC compared to fluconazole, while both PEEZZ and EAEZZ had high MICs compared to fluconazole. From the IC50 (μg/mL) values the potency of the drugs against L. acidophilus in decreasing order were CIPRO – 0.701 ± 0.104; PEEZZ – 1.099 x 105 EAEZZ –172.8 x 105; EEZZ – 26.96 x 105 , ethanol – 9.717 x 1011. The potency pattern based on IC50 (μg/mL) values of the treatments against A. actinomycetemcomitans in decreasing order were PEEZZ > Met & Amox > EEZZ > EAEZZ > ethanol. Potency based on IC50 (μg/mL) values of treatments against C. albicans were not different from that of the other two oral pathogens.
CONCLUSION: Z. zanthoxyloides leaf extracts have anti-microbial activity against the three studied oral pathogens, thus, it can be explored for active anti-microbial agents against oral infections in which the studied pathogens may be implicated.