Medicinal plants and plant remedies have been in use in Ethiopia for centuries. Studies on ethnobotany, ethnomedicine, and ethnoveterinary estimate that nearly 80% of Ethiopians use some type of medicinal plants and plant remedies. Medicinal plants are regarded as the most important and sometimes the only source of therapeutics in the country. Some 800 plant species are used as sources of medicine to treat about 300 physical and mental disorders. However, because these plant species are not adequately studied, there is a big limitation in their documentation, profiling, and management. Moreover, there is a continuous loss of knowledge about medicinal plants because the communities and people are adopting new lifestyles. Hence, this article reports the finding of a study aimed at providing the gross phytochemical characteristics and antimicrobial activities of ethanol and aqueous extracts of fruit, leaf, and stem of
Plants are the integral parts of human cultures in treating human and animal ailments. The worldwide share of plant-derived medicines for treating of human and livestock ailments is still massive [
Fruits of
The plant is a good source of many phytochemicals used against pathogens and predators as well as for treating many human and animal ailments [
Majority of Ethiopian communities use traditional medicine. On the one hand, they have limited access and economic capacity to modern health care services. On the other, they have practical experiences and positive beliefs toward traditional medicine. For example, the authors of this article have known the fruits of
Efforts toward the collection of baseline data on medicinal plants for future phytochemical and pharmacological studies and innovation are very limited. Many scientists have underlined the urgent need for discovering new, safe, and cheap antibiotics with diverse chemical structures, novel chemical actions, and no adverse side effects in response to the emergence of resistant microbial strains to indiscriminate the use of antibiotics [
Ripe fruits, mature leaves, and tender stems of
Phytochemical analyses were performed on the lyophilized fruit, leaf, and stem extracts to identify the phytochemical constituents of the plant. The constituents were then tested using standard procedures for alkaloids, tannins, saponins, flavonoids, terpenoids, and steroids as summarized in Table
Phytochemical tests.
Tests | Procedures |
---|---|
Alkaloids | About half (0.5) gram of each crude extract was stirred in 5 mL of 1% aqueous HCl on a steam bath, cooled and filtered. Then, 1 mL of the filtrate was treated with a few drops of Wagner’s reagent to observe the formation of yellow or brown precipitate |
Flavonoids | Five to ten (5 to 10) drops of dil. HCl and small piece Mg powder was added to 0.5 mL of each extract and boiled for few minutes to observe reddish pink or brown color formation |
Glycosides | Aqueous NaOH solution was added to each extract and was dissolved in 1 mL of water to observe the formation of yellow color |
Saponins | About half (0.5) gram of each extract was mixed, shaken with distilled water in test tube to see the formation and persistency of froth for 15 minutes |
Steroids | About 0.5 mL of each extract was dissolved in 5 mL of chloroform. Then, 5 mL conc. H2SO4 was added by sides of the test tube to observe turning of the upper layer to red color and H2SO4 layer to yellow with green fluorescence |
Terpenoids | Five (5) mL of each extract was mixed in 2 mL of chloroform. Then, a layer was formed by adding 3 mL of conc. H2SO4 to observe reddish color formation in the interface |
The antimicrobial activities of each plant extract were examined against two Gram-negative (
Bacterial colonies were inoculated into liquid nutrient broths and incubated in 200 rpm shaking incubator at 37°C overnight before the date of inoculation. Then, each broth culture was adjusted to match to McFarland 0.50 turbidity standard to get approximately 1 × 108 CFU/mL. Likewise, Mueller–Hinton (M-H) media were prepared according to the procedures given by its manufacturer as growth media for agar disc-diffusion assay and Minimum Inhibition Concentration (MIC) test.
Susceptibility test was carried out using agar disc-diffusion method as outlined by Bari et al. with some modifications [
This test was carried out using serial broth dilution technique [
The phytochemical screening tests of the fruit, leaf, and stem crude extracts of
Phytochemical screening of
SN | Phytochemicals | Fruit extract | Leaf extract | Stem extract |
---|---|---|---|---|
1 | Alkaloids | + | + | + |
2 | Saponins | + | + | + |
3 | Flavonoids | + | + | + |
4 | Glycosides | + | + | + |
5 | Terpenoids | + | + | + |
6 | Steroids | + | + | + |
Ethanol, methanol, and water are the most common polar extraction solvents for plant parts of
Mean bacterial growth inhibition zones of agar disc-diffusion method treated with 50 mg/mL of
Plant parts | Agar disc-diffusion test | Mean of inhibition zone (in mm) | |||
---|---|---|---|---|---|
|
|
|
|
||
Fruit | Ethanol extract | 6.90 | 6.95 | 13.15 | 11.56 |
Streptomycin | 18.75 | 16.78 | 18.11 | 20.25 | |
Gentamicin | 15.73 | 15.68 | 17.82 | 21.32 | |
Aqueous extract | — | — | 10.50 | 10.46 | |
Streptomycin | 16.47 | 17.59 | 16.11 | 15.50 | |
Gentamicin | 16.78 | 14.56 | 12.78 | 16.48 | |
|
|||||
Leaf | Ethanol extract | 16.04 | 13.34 | 16.06 | 11.34 |
Streptomycin | 16.02 | 15.60 | 16.02 | 10.61 | |
Gentamicin | 15.03 | 14.98 | 15.03 | 11.00 | |
Aqueous extract | 13.90 | 12.56 | 14.02 | 10.45 | |
Streptomycin | 18.05 | 18.56 | 18.05 | 19.65 | |
Gentamicin | 16.09 | 17.45 | 16.09 | 14.17 | |
|
|||||
Stem | Ethanol extract | 9.70 | 8.53 | 9.91 | — |
Streptomycin | 19.02 | 18.45 | 19.02 | 12.67 | |
Gentamicin | 19.37 | 17.58 | 19.37 | 17.21 | |
Aqueous extract | — | — | — | — | |
Streptomycin | 13.83 | 14.35 | 13.83 | 15.38 | |
Gentamicin | 15.66 | 14.91 | 15.66 | 19.24 |
Ethanol and aqueous fruit extracts of the plant revealed some degree of antimicrobial activities only against the Gram-negative bacteria (i.e.
Three of the tested bacteria exhibited some susceptibility to ethanol stem extracts of the plant except
We observed that
The minimum inhibition concentrations (MIC) tests of the
Minimum inhibition concentration of ethanol extracts of
SN | Test strain | Extraction solvent | MIC of extracts in mg/mL | ||
---|---|---|---|---|---|
Fruit | Leaf | Stem | |||
1 |
|
Ethanol | 25.00 | 6.25 | 25.00 |
Aqueous | 50.00 | 6.25 | 50.00 | ||
2 |
|
Ethanol | 3.13 | 1.56 | 12.50 |
Aqueous | 6.25 | 6.25 | 50.00 | ||
3 |
|
Ethanol | 50.00 | 1.56 | 12.50 |
Aqueous | 50.00 | 6.25 | 50.00 | ||
4 |
|
Ethanol | 12.50 | 12.50 | 50.00 |
Aqueous | 12.50 | 12.50 | 50.00 |
Many ethnobotanic, ethnomedicinal, and ethnoveterinary studies have reported that
The data used to support the findings of this study are available from the corresponding author upon request.
The authors declare no conflicts of interest.
Mekelle University, Ethiopia, has funded this research. The authors are very grateful for the funding.