Author/Authors :
Esmaeel, Zubaida A. University of Baghdad - College of Science - Department of Biology, Iraq , AL-Jobori, Kamil M. University of Baghdad - College of Science - Department of Biology, Iraq
Abstract :
The present study has been conducted to evaluate the inhibitory effects of the aerial plant part (leaves and bark) extracts of D. viscosa before and during flowering against some pathogenic bacteria for human, plants, and against yeast (Candida albicans) by using different polarity organic solvents: Ethanol and Diethyl ether.The agar well diffusion method was used to evaluate the inhibitory actions of these extracts with eight concentrations: 0, 2.5, 5, 10, 20, 30, 40 or 50 mg/ml. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values were also determined, in addition to compare the results of the plant extracts with the results of the susceptibility of pathogenic microorganisms for antibiotics, The completely randomized design (CRD) was used with three replications. Better effect was observed in the liquid dilution assay with all extracts showing a degree of effect. The results showed that ethanolic extracts of the bark and leaves, and diethyl ether extracts of the leaves demonstrated clear inhibitory effect against the tested microorganisms. ethanolic extracts of the bark was superior over leaf extracts in the inhibitory effects on the growth of C. albicans. In general, the results showed no significant differences between the concentrations of 30, 40 or 50 mg/ml. The microbial screening showed that the MIC of ethanolic extracts of the bark before and during flowering was at a concentration of 2.5 mg/ml, and for leaf extracts ranged between 2.5-10 mg/ml. As for MBC effects was ranged between 5- 50 mg/ml, depending on the type of solvents, microorganism and the period of collection (before or during flowering). In comparison with antibiotics, the results showed high similitude between D. viscosa extracts at concentrations of 30, 40 or 50 mg/ml and antibiotics against the tested microorganisms. When our results compares with other studies that conducted in other parts of the world, we concluded that the type of solvent, method of extraction, period of collection (before or during flowering) and the geographical distribution of D. viscosa significantly affect the rate of the chemical components and its effect against microorganisms