- Title
- Pharmacological evaluation of phragmanthera capitata (sprengel) balle, loranthaceae :a parasiticmistletoe growing on rubber trees
- Creator
- Ohikhena, Franklin Uangbaoje
- Subject
- Hevea Hevea -- Diseases and pests Rubber
- Date
- 2017
- Type
- Thesis
- Type
- Doctoral
- Type
- PhD
- Identifier
- http://hdl.handle.net/10353/8899
- Identifier
- vital:33937
- Description
- Rubber tree (Hevea brasiliensis Muell.) is the world’s major source of natural rubber and a major non-oil, agricultural export commodity in the producing countries in Africa. However, it is highly susceptible to specific mistletoes of the Loranthaceae family. Phragmanthera capitate (Sprengel) Balle is the major mistletoe parasitizing the rubber tree plantations in Africa and hence, alongside with other mistletoes, has attracted indiscriminate destruction from plantation owners. Indiscriminate destruction of plants could be as a result of ignorance of the importance or benefit(s) of the plants and this could lead to their extinction if not checked. Hence, there is the need for scientific documentation of plants and their uses because, from the pharmacological perception, the destruction of a plant could result in the permanent loss of a potential drug. Therefore, this study was aimed at documenting and evaluating the pharmacological potentials of P. capitata collected from rubber tree. Fresh leaves were gently rinsed with water and dried. Dried leaves were pulverised and kept at 4oC when not in use. Pulverised leaves were extracted with acetone, methanol, ethanol and water and concentrated to give the respective solvent crude extracts used in most of the assays. From the extraction, Methanol had the highest yield of 21.5percent, water had 10.8percent and acetone was 6.87percent while ethanol had the lowest yield of 4.3percent. Standard spectrophotometry assays on the extracts were used to quantify some major phytochemicals of pharmacological interest and also to determine the antioxidant potentials of the sample. The result revealed high amounts of phenols (175.53 ± 0.32 mg GAE/g to 218.62 ± 3.38 mg GAE/g), flavonoids (197.06 ± 3.80 mg QE/mg to 679.82 ± 6.26 mg QE/g) and proanthocyanidins (128.83 ± 1.69 mg CE/g to 645.68 ± 6.35 mg CE/g) with the acetone extract having the highest amount of the phytochemicals while the aqueous extract had the least. The results of the antioxidant assays revealed that the sample had high radical scavenging potentials with comparable inhibitory concentrations to standard antioxidant drugs. The proximate and mineral analysis on the pulverised sample showed that it is rich in carbohydrate with a composition of 57.73 ± 0.33 g/100 g. Protein, fat and fibre compositions were 12.50 ± 0.50 g/100 g, 3.34 ± 0.18 g/100 g and 11.66 ± 0.54 g/100g. The total energy composition was 310.97 ± 2.30 Kcal/100 g. The mineral composition revealed high potassium level of 1047.83 ± 34 mg/100g. Calcium (6.22.58 ± 0.01 mg/100g), magnesium (361.15 ± 0.01 mg/100 g) and phosphorous (115.40 ± 0.01 mg/100 g) were also present in appreciable amounts. The toxicity of the four extracts was assayed using brine shrimp. The LC50 in all the solvent extracts was greater than 1 mg/mL which according to Meyer’s index and other indexes signify “no toxicity” for crude plant extracts. Antimicrobial activity of the extracts was done using the minimal inhibitory concentration (MIC) assay against 10 bacteria (Enterococcus faecalis, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Streptococcus pyogenes, Vibrio cholera, Klebsiella pneumonia, Pseudomonas aeruginosa, Salmonella typhi and Escherichia coli) and 4 fungi (Trichophyton mucoides, Trichophyton tonsurans, Candida albicans and Aspergillus niger) of human pathogenic strains. The MIC of the antibacterial assay ranged from 1.25 mg/mL to 5 mg/mL for the organic extracts while no activity was observed in the aqueous extract at the highest concentration tested. However, the aqueous extract had a great inhibitory activity on all four of the tested fungi with a MIC of ≤ 0.3125 mg/mL to 1.25 mg/mL while only two fungi (Trichophyton Tonsurans and Aspergillus niger) were susceptible to the organic extracts. The MIC of the TB causative pathogen, Mycobacterium tuberculosis (H37Rv) strain ranged from 25 μg/mL (acetone and aqueous extracts) to 50 μg/mL in the ethanol extract while it was > 50 μg/mL (highest concentration tested) in the methanol extract. This study revealed that the sample has the potential in phytotherapy against oxidative stresses (inflammations) caused by free radicals. It could also be a useful herb in combating diseases caused by pathogenic organisms. The high anti-Mycobacterium tuberculosis activity observed in this study suggests it could be a plant with high promise in the fight against tuberculosis. The toxicity evaluation signifies it is safe for further plant-based pharmaceutical explorations. This study also validated some reported ethnopharmacological uses of this plant and call for its protection from indiscriminate destruction in rubber plantations and other crop gardens/plantations in the world.
- Format
- 144 leaves
- Format
- Publisher
- University of Fort Hare
- Publisher
- Faculty of Science and Agriculture
- Language
- English
- Rights
- University of Fort Hare
- Hits: 732
- Visitors: 917
- Downloads: 389
Thumbnail | File | Description | Size | Format | |||
---|---|---|---|---|---|---|---|
View Details | SOURCE1 | Franklin Uangbaoje Ohikhena PhD Thesis.pdf | 3 MB | Adobe Acrobat PDF | View Details |