Evaluation and identification of microbial contaminants in polyherbal medicines used for the treatment of tuberculosis in Amathole District Municipality, Eastern Cape Province, South Africa
- Authors: Famewo, Elizabeth Bosede
- Date: 2018
- Subjects: Tuberculosis -- Treatment -- South Africa Mycobacterial diseases -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9680 , vital:34818
- Description: Tuberculosis is caused by Mycobacterium tuberculosis. The emergence of drug-resistant strains of this organism has become a global public health problem. In the continuing search for effective treatment, polyherbal medicines offer a great hope in the development of alternative drugs for the treatment of tuberculosis. The use of herbal formulations for therapeutic purposes has significantly increased in the developed and developing countries because of their curative property, less toxicity and minimal side effects. However, there is little information on their safety and effectiveness in the literature. To address this, polyherbal medicines used for the treatment of tuberculosis in the Eastern Cape Province of South Africa were evaluated. Ethno-medicinal survey was conducted through semi-structured questionnaires coupled with informal conversations with the herbal sellers in five communities in the study area. Bacterial and fungal DNA was extracted from the polyherbal medicines purchased. A fragment of the bacterial 16S rRNA gene and internal transcribed spacer region of the fungal rRNA operon were amplified with universal primers 27F and 518R, and ITS1 and ITS4 respectively. Following standard procedures, the amplicons were finally run on Illumina’s MiSeq platform. Furthermore, the remedies were screened against Mycobacterium tuberculosis H37Rv using Middlebrook 7H9 media and MGIT BACTEC 960 system. Agar dilution method was used to determine the minimum inhibitory concentration (MIC) of the remedies against eight bacteria and three fungi isolates. The herbal preparations were assayed for their toxicity using hatchability success and larval mortality of Artemia salina Leach. Finally, their nutritive properties were analysed using an inductively coupled plasma optical emission spectrometer for mineral analysis while the vitamins were determined using standardized methods A total of nine polyherbal preparations were collected. The herbs used for the preparation of these remedies belong to 20 families. Apiaceae [5(25 percent)] was the most prominent plant family used, followed by Liliaceae [4(20 percent)], Strychnaceae [4(20 percent)], Rutaceae [4(20 percent)] and Hypoxidaceae [3(15 percent)]. The two most frequently used plants were Allium sativum L. (Liliaceae) and Strychnos decussata (Pappe) Gilg. (Strychnaceae). Rhizomes was the most common parts used, followed by the roots and barks. The herbal medicines were prepared mainly by infusion and decoction. The presences of pathogenic and non-pathogenic bacteria were identified in the polyherbal medicines. Generally, the most common bacteria identified from the samples were Bacillus sp., Enterobacter sp., Klebsiella sp., Rahnella sp., Paenibacillus sp., Clostridium sp. and Pantoea sp. The predominant mycoflora obtained belongs to different genera or species of fungi; these include Alternaria, Candida, Ramularia, Cladosporium, Penicillium, Aspergillus and Malassezia. The susceptibility testing revealed that all the remedies contain anti-tubercular activity against M. tuberculosis H37Rv at concentrations below 50 ug/ml. Seven of the polyherbal preparations showed activity at concentrations below 25 ug/ml. The MIC values exhibited inhibitory activity at 1.562 μg/ml. However, isoniazid showed more inhibitory activity against M. tuberculosis at 0.05 μg/ml when compared to the polyherbal remedies. The inhibitory activity of the polyherbal medicines based on the overall MIC revealed that Hogsback first site (HBfs) and Fort Beaufort (FB) remedies were the most active remedies against the bacterial isolates at the concentration of 2.5 mg/mL. Among the nine herbal formulations, only King Williams Town site A (KWTa) remedy showed activity against Aspergillus niger and Aspergillus fumigatus with the MIC valve of 2.5 mg/mL. While King Williams Town site C (KWTc) and Hogsback third site (HBts) had the highest activity at 1.25 mg/mL against Candida albicans, the remaining remedies were active at 2.5 mg/mL. The percentage hatchability of 44.42 percent, 42.96 percent and 39.70 percent were observed in A. salina cysts incubated with herbal preparations from KWTa, HBfs and HBts respectively. The hatching success of the cysts in these remedies was significantly higher than the positive control (nystatin) and the negative control (sea water) at p < 0.05. The mortality of A. salina nauplii incubated in Alice (AL), King Williams Town site B (KWTb) and KWTc remedies were significantly higher than when larvae were incubated in both controls. Based on Meyer’s index, the LD50 of each polyherbal medicine was between 2.9 and 4.0 mg/ml, the LD50 values greater than 1 mg/ml, an indication that they are not toxic. The polyherbal preparations were found to be rich in vitamins and mineral nutrients. Calcium was the highest macronutrient detected while the lowest nutrient was phosphorus. Iron was the highest micronutrient in the majority of the polyherbal preparations while the lowest value was recorded for copper. Vitamin C was absent in the herbal preparations while vitamin A and E were detected. This study provides significant ethno-medicinal information on polyherbal medicines used for the treatment of TB in the study area. The presence of the identified bacteria and fungi in the herbal formulations is a cause for concern. However, the ability of the remedies to possess activity against Mycobacterium tuberculosis and other pathogenic microorganisms associated with tuberculosis infection makes them potential sources of new antimycobacterial agents. Also, they are rich sources of mineral nutrients, and are as well non-toxic, thus, they are safe for consumption. In view of their anti-tubercular properties, this study has provided a better understanding of the reasons why TB-patients make use of these polyherbal formulations. Also, the study supports the folkloric use of polyherbal medicines in the treatment of tuberculosis in the Eastern Cape Province, South Africa.
- Full Text:
- Date Issued: 2018
- Authors: Famewo, Elizabeth Bosede
- Date: 2018
- Subjects: Tuberculosis -- Treatment -- South Africa Mycobacterial diseases -- South Africa -- Eastern Cape Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9680 , vital:34818
- Description: Tuberculosis is caused by Mycobacterium tuberculosis. The emergence of drug-resistant strains of this organism has become a global public health problem. In the continuing search for effective treatment, polyherbal medicines offer a great hope in the development of alternative drugs for the treatment of tuberculosis. The use of herbal formulations for therapeutic purposes has significantly increased in the developed and developing countries because of their curative property, less toxicity and minimal side effects. However, there is little information on their safety and effectiveness in the literature. To address this, polyherbal medicines used for the treatment of tuberculosis in the Eastern Cape Province of South Africa were evaluated. Ethno-medicinal survey was conducted through semi-structured questionnaires coupled with informal conversations with the herbal sellers in five communities in the study area. Bacterial and fungal DNA was extracted from the polyherbal medicines purchased. A fragment of the bacterial 16S rRNA gene and internal transcribed spacer region of the fungal rRNA operon were amplified with universal primers 27F and 518R, and ITS1 and ITS4 respectively. Following standard procedures, the amplicons were finally run on Illumina’s MiSeq platform. Furthermore, the remedies were screened against Mycobacterium tuberculosis H37Rv using Middlebrook 7H9 media and MGIT BACTEC 960 system. Agar dilution method was used to determine the minimum inhibitory concentration (MIC) of the remedies against eight bacteria and three fungi isolates. The herbal preparations were assayed for their toxicity using hatchability success and larval mortality of Artemia salina Leach. Finally, their nutritive properties were analysed using an inductively coupled plasma optical emission spectrometer for mineral analysis while the vitamins were determined using standardized methods A total of nine polyherbal preparations were collected. The herbs used for the preparation of these remedies belong to 20 families. Apiaceae [5(25 percent)] was the most prominent plant family used, followed by Liliaceae [4(20 percent)], Strychnaceae [4(20 percent)], Rutaceae [4(20 percent)] and Hypoxidaceae [3(15 percent)]. The two most frequently used plants were Allium sativum L. (Liliaceae) and Strychnos decussata (Pappe) Gilg. (Strychnaceae). Rhizomes was the most common parts used, followed by the roots and barks. The herbal medicines were prepared mainly by infusion and decoction. The presences of pathogenic and non-pathogenic bacteria were identified in the polyherbal medicines. Generally, the most common bacteria identified from the samples were Bacillus sp., Enterobacter sp., Klebsiella sp., Rahnella sp., Paenibacillus sp., Clostridium sp. and Pantoea sp. The predominant mycoflora obtained belongs to different genera or species of fungi; these include Alternaria, Candida, Ramularia, Cladosporium, Penicillium, Aspergillus and Malassezia. The susceptibility testing revealed that all the remedies contain anti-tubercular activity against M. tuberculosis H37Rv at concentrations below 50 ug/ml. Seven of the polyherbal preparations showed activity at concentrations below 25 ug/ml. The MIC values exhibited inhibitory activity at 1.562 μg/ml. However, isoniazid showed more inhibitory activity against M. tuberculosis at 0.05 μg/ml when compared to the polyherbal remedies. The inhibitory activity of the polyherbal medicines based on the overall MIC revealed that Hogsback first site (HBfs) and Fort Beaufort (FB) remedies were the most active remedies against the bacterial isolates at the concentration of 2.5 mg/mL. Among the nine herbal formulations, only King Williams Town site A (KWTa) remedy showed activity against Aspergillus niger and Aspergillus fumigatus with the MIC valve of 2.5 mg/mL. While King Williams Town site C (KWTc) and Hogsback third site (HBts) had the highest activity at 1.25 mg/mL against Candida albicans, the remaining remedies were active at 2.5 mg/mL. The percentage hatchability of 44.42 percent, 42.96 percent and 39.70 percent were observed in A. salina cysts incubated with herbal preparations from KWTa, HBfs and HBts respectively. The hatching success of the cysts in these remedies was significantly higher than the positive control (nystatin) and the negative control (sea water) at p < 0.05. The mortality of A. salina nauplii incubated in Alice (AL), King Williams Town site B (KWTb) and KWTc remedies were significantly higher than when larvae were incubated in both controls. Based on Meyer’s index, the LD50 of each polyherbal medicine was between 2.9 and 4.0 mg/ml, the LD50 values greater than 1 mg/ml, an indication that they are not toxic. The polyherbal preparations were found to be rich in vitamins and mineral nutrients. Calcium was the highest macronutrient detected while the lowest nutrient was phosphorus. Iron was the highest micronutrient in the majority of the polyherbal preparations while the lowest value was recorded for copper. Vitamin C was absent in the herbal preparations while vitamin A and E were detected. This study provides significant ethno-medicinal information on polyherbal medicines used for the treatment of TB in the study area. The presence of the identified bacteria and fungi in the herbal formulations is a cause for concern. However, the ability of the remedies to possess activity against Mycobacterium tuberculosis and other pathogenic microorganisms associated with tuberculosis infection makes them potential sources of new antimycobacterial agents. Also, they are rich sources of mineral nutrients, and are as well non-toxic, thus, they are safe for consumption. In view of their anti-tubercular properties, this study has provided a better understanding of the reasons why TB-patients make use of these polyherbal formulations. Also, the study supports the folkloric use of polyherbal medicines in the treatment of tuberculosis in the Eastern Cape Province, South Africa.
- Full Text:
- Date Issued: 2018
Development of conservation strategies for Alepidea Amatymbica ECKL. & ZEYH. : a rare medicinal plant in the Eastern Cape, South Africa
- Mangoale, Ramatsobane Maureen
- Authors: Mangoale, Ramatsobane Maureen
- Date: 2017
- Subjects: Medicinal plants Plants, Cultivated
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/8667 , vital:33400
- Description: Conservation through cultivation has been recommended as a means to relieve overexploitation of medicinal plants. However, the medicinal plants users believe that plants collected from the wild are more potent than cultivated ones. Hence, there is a need for scientific documentation of the potency of cultivated medicinal plants to contribute to the development of a sustainable management strategy to conserve wild populations. This study was aimed at documenting cultivation techniques of a known medicinal plant, Alepidea amatymbica and to validate its medicinal efficacy. In order to identify overexploited medicinal plants in the study area and thus develop their conservation strategy, a survey on the trade of medicinal plants was conducted in selected towns of Amathole District Municipality of the Eastern Cape, South Africa. The survey revealed 67 plants belonging to 46 different families. Twenty-five medicinal plants were identified as overexploited and scarce and they were prioritized for conservation. Furthermore, 69.14 percent of the respondents were not willing to use cultivated medicinal plants. Lack of belief on the potency of cultivated plants and cultivation techniques were mentioned as the most significant constraints to conservation of medicinal plants. Also, the time for cultivated plants to reach maturity deterred herbal medicine practitioners from cultivating them. Alepidea amatymbica was mentioned as one of the most overexploited medicinal plants which has become scarce in the study area. This medicinal plant was therefore selected for this study. In order to develop sustainable conservation program for the species, various studies which include survey on the medicinal plants trade, cultivation, comparative micromorphology, elemental composition, toxicity, phytochemical and antioxidant activity of the wild and cultivated A. amatymbica were conducted. Cultivation of Alepidea amatymbica was conducted to determine the appropriate planting depth and rhizome fragment length for the growth of this plant. The experiment was laid out in a Complete Randomized Block Design (CRBD) with two factors in 6×3 factorial design. There were six levels of fragment length (1, 2, 3, 4, 5 and 6 cm) and three levels of burial depth (2.5, 5 and 7.5 cm). Emergence rate, number of leaves, leaf area, and plant height, number of florets, rhizome length gain, rhizome weight gain, shoot moisture and rhizome moisture were measured as growth parameters. The best overall yield in terms of plant height, shoot emergence, rhizome weight gain, number of florets and number of leaves was observed in 7.5 cm planting depth at 6 cm rhizome length. Four centimetre rhizome length had the highest leaf area of 111.9±3.5 cm2, 101.3±3.5 cm2, 105±3.5 cm2 at 2.5, 5, 7.5 cm planting depth respectively. Shorter fragment lengths showed high potential for vegetative propagation in terms of rhizome length gain at all burial depths. Scanning electron microscopy (SEM) was used to examine the foliar micro morphological characteristics while energy dispersive x-ray spectroscopy (EDXS) was used to determine the elemental composition in different parts of the wild and cultivated plants. The study revealed numerous differences between the wild and cultivated ones. These include deposition of epicuticular waxes, stomatal apparatus, helical thickening of the xylem walls, thickening of the epidermal cell layer and presence of starch grains in the parenchyma cells of the cortex. The EDXS analysis also revealed disproportionate quantities of C, O, Ca, K, Al, Mg, Si, Br and N as the major constituents in both cultivated and wild A. amatymbica specimens. The quantities of elements varied in the different parts of wild and cultivated plants. Toxicity of the methanol, water and acetone extracts of the fresh rhizome of the wild and cultivated A. amatymbica were evaluated using hatchability of cysts and lethality on the hatched cysts (nauplii) of Artemia salina. The highest hatching success was observed in the water extracts of the wild plant (46.16percent) with a MIC of 0.184 mg/ml while the cultivated plants had a hatching success of 40.83percent with MIC of 0.208 mg/ml. Highest mortality was observed in the acetone extract of the wild plants at the lethal dose of 0.191 mg/ml while the cultivated plant had a lethal dose of 0.270 mg/ml. Water extracts of both wild and cultivated plants showed similar lethal dose (LD50) of >1 mg/ml. Methanol extracts of both the wild and cultivated species exhibited almost the same level of toxicity (0.695 mg/ml and 0.628 mg/ml, respectively). Based on the Bastos criterion of toxicity indices of the lethality test, all the plant fractions demonstrated cytotoxicity effect, although the degree of their toxicity varied among the plants used. Standard spectrophotometry assays were used to quantify the phytochemical contents and to determine the antioxidant potentials of the cultivated and wild A. amatymbica. The results revealed different levels of phytochemicals with corresponding antioxidant activities. The wild extracts had higher phytochemical contents in most of the assays than cultivated extracts. Total phenol in the wild extracts ranged from 32.30±3.43 to 117.8±8.45 mg GAE/g with the acetone extracts having the highest content while the water extracts was the least. The range in the total phenol of the cultivated species was 66.46±5.29 to 98.44±6.08 mg GAE/g with the methanol extracts having the highest content while water extracts was the least. The flavonoids content ranged from 55.01±6.51 to 99.09±7.20 mg QE/mg and from 48.65±7.74 to 67.32±4.1 mg QE/mg for the wild and cultivated plants, respectively. The alkaloids contents ranged from 14.70±0.04 to 17.80±0.015 percent in the wild species while it ranged from 11.98±0.14 to 13.21±0.06 percent in the cultivated species. The wild species also showed higher antioxidant activities in most of the assays evaluated. The study revealed successful cultivation of the wild species of Alepidea amatymbica using fragments from the rhizome. The micromorphological study of both the wild and cultivated species showed minimal differences in the helical thickening of the walls in the xylem vessels and starch grain accumulation pattern. Although herbal medicine practitioners believe that cultivated species are not potent, however this study revealed some levels of phytochemicals contents and antioxidant activities which are comparable to the wild species. Cultivation is a major strategy in conserving nature and their resources. Hence, the successful domestication of A. amatymbica would help in reducing the pressure on the wild species while also meeting their medicinal demands purposes, utilisation and conserving for future generations.
- Full Text:
- Date Issued: 2017
- Authors: Mangoale, Ramatsobane Maureen
- Date: 2017
- Subjects: Medicinal plants Plants, Cultivated
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/8667 , vital:33400
- Description: Conservation through cultivation has been recommended as a means to relieve overexploitation of medicinal plants. However, the medicinal plants users believe that plants collected from the wild are more potent than cultivated ones. Hence, there is a need for scientific documentation of the potency of cultivated medicinal plants to contribute to the development of a sustainable management strategy to conserve wild populations. This study was aimed at documenting cultivation techniques of a known medicinal plant, Alepidea amatymbica and to validate its medicinal efficacy. In order to identify overexploited medicinal plants in the study area and thus develop their conservation strategy, a survey on the trade of medicinal plants was conducted in selected towns of Amathole District Municipality of the Eastern Cape, South Africa. The survey revealed 67 plants belonging to 46 different families. Twenty-five medicinal plants were identified as overexploited and scarce and they were prioritized for conservation. Furthermore, 69.14 percent of the respondents were not willing to use cultivated medicinal plants. Lack of belief on the potency of cultivated plants and cultivation techniques were mentioned as the most significant constraints to conservation of medicinal plants. Also, the time for cultivated plants to reach maturity deterred herbal medicine practitioners from cultivating them. Alepidea amatymbica was mentioned as one of the most overexploited medicinal plants which has become scarce in the study area. This medicinal plant was therefore selected for this study. In order to develop sustainable conservation program for the species, various studies which include survey on the medicinal plants trade, cultivation, comparative micromorphology, elemental composition, toxicity, phytochemical and antioxidant activity of the wild and cultivated A. amatymbica were conducted. Cultivation of Alepidea amatymbica was conducted to determine the appropriate planting depth and rhizome fragment length for the growth of this plant. The experiment was laid out in a Complete Randomized Block Design (CRBD) with two factors in 6×3 factorial design. There were six levels of fragment length (1, 2, 3, 4, 5 and 6 cm) and three levels of burial depth (2.5, 5 and 7.5 cm). Emergence rate, number of leaves, leaf area, and plant height, number of florets, rhizome length gain, rhizome weight gain, shoot moisture and rhizome moisture were measured as growth parameters. The best overall yield in terms of plant height, shoot emergence, rhizome weight gain, number of florets and number of leaves was observed in 7.5 cm planting depth at 6 cm rhizome length. Four centimetre rhizome length had the highest leaf area of 111.9±3.5 cm2, 101.3±3.5 cm2, 105±3.5 cm2 at 2.5, 5, 7.5 cm planting depth respectively. Shorter fragment lengths showed high potential for vegetative propagation in terms of rhizome length gain at all burial depths. Scanning electron microscopy (SEM) was used to examine the foliar micro morphological characteristics while energy dispersive x-ray spectroscopy (EDXS) was used to determine the elemental composition in different parts of the wild and cultivated plants. The study revealed numerous differences between the wild and cultivated ones. These include deposition of epicuticular waxes, stomatal apparatus, helical thickening of the xylem walls, thickening of the epidermal cell layer and presence of starch grains in the parenchyma cells of the cortex. The EDXS analysis also revealed disproportionate quantities of C, O, Ca, K, Al, Mg, Si, Br and N as the major constituents in both cultivated and wild A. amatymbica specimens. The quantities of elements varied in the different parts of wild and cultivated plants. Toxicity of the methanol, water and acetone extracts of the fresh rhizome of the wild and cultivated A. amatymbica were evaluated using hatchability of cysts and lethality on the hatched cysts (nauplii) of Artemia salina. The highest hatching success was observed in the water extracts of the wild plant (46.16percent) with a MIC of 0.184 mg/ml while the cultivated plants had a hatching success of 40.83percent with MIC of 0.208 mg/ml. Highest mortality was observed in the acetone extract of the wild plants at the lethal dose of 0.191 mg/ml while the cultivated plant had a lethal dose of 0.270 mg/ml. Water extracts of both wild and cultivated plants showed similar lethal dose (LD50) of >1 mg/ml. Methanol extracts of both the wild and cultivated species exhibited almost the same level of toxicity (0.695 mg/ml and 0.628 mg/ml, respectively). Based on the Bastos criterion of toxicity indices of the lethality test, all the plant fractions demonstrated cytotoxicity effect, although the degree of their toxicity varied among the plants used. Standard spectrophotometry assays were used to quantify the phytochemical contents and to determine the antioxidant potentials of the cultivated and wild A. amatymbica. The results revealed different levels of phytochemicals with corresponding antioxidant activities. The wild extracts had higher phytochemical contents in most of the assays than cultivated extracts. Total phenol in the wild extracts ranged from 32.30±3.43 to 117.8±8.45 mg GAE/g with the acetone extracts having the highest content while the water extracts was the least. The range in the total phenol of the cultivated species was 66.46±5.29 to 98.44±6.08 mg GAE/g with the methanol extracts having the highest content while water extracts was the least. The flavonoids content ranged from 55.01±6.51 to 99.09±7.20 mg QE/mg and from 48.65±7.74 to 67.32±4.1 mg QE/mg for the wild and cultivated plants, respectively. The alkaloids contents ranged from 14.70±0.04 to 17.80±0.015 percent in the wild species while it ranged from 11.98±0.14 to 13.21±0.06 percent in the cultivated species. The wild species also showed higher antioxidant activities in most of the assays evaluated. The study revealed successful cultivation of the wild species of Alepidea amatymbica using fragments from the rhizome. The micromorphological study of both the wild and cultivated species showed minimal differences in the helical thickening of the walls in the xylem vessels and starch grain accumulation pattern. Although herbal medicine practitioners believe that cultivated species are not potent, however this study revealed some levels of phytochemicals contents and antioxidant activities which are comparable to the wild species. Cultivation is a major strategy in conserving nature and their resources. Hence, the successful domestication of A. amatymbica would help in reducing the pressure on the wild species while also meeting their medicinal demands purposes, utilisation and conserving for future generations.
- Full Text:
- Date Issued: 2017
Impact of formulated soil types on growth performance, phytochemical constituents and pharmacological properties of solanum nigurm L. : a wild vegetable in the Eastern Cape Province, South Africa
- Authors: Ogundola, Adijat Funke
- Date: 2017
- Subjects: Solanum Materia medica, Vegetable Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8758 , vital:33519
- Description: Solanum nigrum L. is a wild vegetable that is highly recognised for its high nutiritional and therapeutical purposes. However, proper identification of the plant is essential not only to plant scientists but to a wide range of users. Therefore, the plant’s roots, stems and leaves cultivated on different soil types were viewed under the Scanning Electron Microscope while the leaves were further viewed under the Light Microscope. significant increase was observed in densities of stomata, guard and subsidiary cells of leaves of S. nigrum grown on silty clay loam soil. The SEM analysis revealed abundant glandular and non-glandular trichromes on both surfaces of the leaves. The glandular trichome is known to be responsible for the storage of bioactive compounds for which this plant is well known. Cultivation was embarked upon, for the availability of the plant at all times. However, propagation was by seed alone, therefore, quality seed is necessary for cultivation. Study was carried out on seeds extracted from plants growing in the wild in Alice for the seed viability, germination and seedling emergence when subjected to different soil texture types and sowing depths. The seeds were 98.3 percent viable. Highest germination (94.66 percent) was recorded in sand paper scarification, 15, 20 and 25ºC. Continuous darkness and temperatures lower than 5ºC and higher than 35ºCwere detrimental to the seeds. Silty clay loam soil and a depth of 2 cm had the highest seedling emergence 90 percent and recommended as the ideal condition for seedlings emergence. The growth, yield and physiological response of S. nigrum to sandy clay loam, silty clay loam, clay loam, loam soils and control soil (sandy loam) were investigated in the glasshouse in two separate trials. The ANOVA analysed data results indicated that plant samples on silty clay loam significantly increased in height, stem girth, plant root, leaf area, number of leaves, number of branches, number of flowers, number of fruit bunch per plant dry weight, as well as weight of fruit bunch. However, plant samples grown on clay loam and loam soils recorded increased chlorophyll and produced dark green leaves. It is conceivable that silty clay loam soils have a strong ability to support the physiological growth and the yield of S. nigrum. These soils are therefore recommended for the cultivation of this plant. S. nigrum cultivated on these soils was evaluated for proximate compositions, anti-nutrients, vitamins A, C and E and mineral compositions using standard analytical methods. Using the translocation factor, the minerals’ toxicity accumulation levels in the plant were also determined. Accumulation of proximate parameters in the first and second trials are: ash (11.25-12.25 percent and 11.14- 11.54 percent), crude fibre (19.24-19.95 percent and 18.71-19.35 percent), protein (36.72-38.98 percent and 34.47-37.00 percent), phytate (0.84-1.17 and 0.88-1.15 mg/ml), saponnin (94.10-97.00 and 94.17-97.00 percent) and alkaloids (43.03-45.76 and 42.08- 44.10 percent) respectively. Vitamin A ranged between 117 and 137 mg/kg and betweens 108 and 128 mg/kg, vitamin C between 100 and 118 mg/kg and between 96 and 108 mg/kg and vitamin E between 250 and 269 mg/kg and between 227 and 261 mg/kg in the first and second trials respectively. The quantities of macro and micro-nutrients recorded in S. nigrum showed that this plant is a reservoir of nutrients. Plants cultivated on clay loam, silty clay loam and loam soils accumulated elevated nutritients compositions. Investigation was made on the ability of S. nigrum cultivated on different soil texture types to synthesise phytochemicals such as phenol, flavonoid, alkaloid proanthocyanidins, tannins, saponins and antioxidant. Highest concentrations of phenolics (73.87 mg/g), flavonoids (58.41 mg/g), proanthocyanidins (875.74 mg/g), tannins (49.32 mg/g), saponins (875.74 mg/g) and alkaloid (47.50 mg/g) contents were recorded in plant sample cultivated on silty clay loam soil. Also, highest radical scavenging power using DPPH (0.0102 mg/g), ABTS (0.1062 mg/g) and FRAP (0.8395 mg/g) were recorded in plant samples grown on silty clay loam and the next high values were recorded in plant samples grown on clay loam soil. It is showed in this study that silty clay loam soil and clay loam soils are the best soil types for cultivation of S. nigrum for increased antioxidant properties/ oxygen radical scavenging activities. Investigation was made on chemical compositions and antioxidant properties of essential oil extracts of S. nigrum shoot and root cultivated on different soil textures. The Gas Chromatography-Mass Spectrometry (GC-MS) profiling revealed variations in the quality index (QI) and number of chemical constituents of the oil of S. nigrum cultivated on different soil texture types. Geraniol and citronellol were two principal components of high quality common to oil from shoots and roots fromplants cultivated on all soil types. Results of DPPH and ABTS assays of the shoot oil showed that S. nigrum cultivated on clay loam soil had the highest antioxidant power. The presence of citronellol and geraniol among the major compounds is an indicaton of the plant’s role in defensive mechanisms. The work indicated that soil texture has effect on the quality, quantity and chemical compounds synthesised in the shoots and roots of S. nigrum. Antibacterial activities and the efficacy of S. nigrum cultivated on different soil types were carried out on reference strains of 4 gram-positive and 4 gram-negative bacteria. Toxicity evaluation of the plant’s acetone extract and water extract were also assessed on lethality of brine shrimp eggs. Plant water and acetone extracts exhibited strong antibacterial activity against Pseudomona aeruginosa, acetone extracts against Bacillus cereus, Listeria and Escherichia coli. Significantly (p< 0.05) low concentration (0.25 mg/mL) of acetone extracts from plant shoot cultivated on silty clay loam and clay loam soils inhibited B. cereus and P. aeruginosa. Antimicrobial activities of extracts of plant cultivated on clay loam appeared to be more superior to extracs from plants grown on other soil types. Toxicity of the plant extracts (water and acetone) was concentration and time dependent. The LD50 values for all plant extracts were greater than 1000 mg/mL which showed they are non-toxic.
- Full Text:
- Date Issued: 2017
- Authors: Ogundola, Adijat Funke
- Date: 2017
- Subjects: Solanum Materia medica, Vegetable Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8758 , vital:33519
- Description: Solanum nigrum L. is a wild vegetable that is highly recognised for its high nutiritional and therapeutical purposes. However, proper identification of the plant is essential not only to plant scientists but to a wide range of users. Therefore, the plant’s roots, stems and leaves cultivated on different soil types were viewed under the Scanning Electron Microscope while the leaves were further viewed under the Light Microscope. significant increase was observed in densities of stomata, guard and subsidiary cells of leaves of S. nigrum grown on silty clay loam soil. The SEM analysis revealed abundant glandular and non-glandular trichromes on both surfaces of the leaves. The glandular trichome is known to be responsible for the storage of bioactive compounds for which this plant is well known. Cultivation was embarked upon, for the availability of the plant at all times. However, propagation was by seed alone, therefore, quality seed is necessary for cultivation. Study was carried out on seeds extracted from plants growing in the wild in Alice for the seed viability, germination and seedling emergence when subjected to different soil texture types and sowing depths. The seeds were 98.3 percent viable. Highest germination (94.66 percent) was recorded in sand paper scarification, 15, 20 and 25ºC. Continuous darkness and temperatures lower than 5ºC and higher than 35ºCwere detrimental to the seeds. Silty clay loam soil and a depth of 2 cm had the highest seedling emergence 90 percent and recommended as the ideal condition for seedlings emergence. The growth, yield and physiological response of S. nigrum to sandy clay loam, silty clay loam, clay loam, loam soils and control soil (sandy loam) were investigated in the glasshouse in two separate trials. The ANOVA analysed data results indicated that plant samples on silty clay loam significantly increased in height, stem girth, plant root, leaf area, number of leaves, number of branches, number of flowers, number of fruit bunch per plant dry weight, as well as weight of fruit bunch. However, plant samples grown on clay loam and loam soils recorded increased chlorophyll and produced dark green leaves. It is conceivable that silty clay loam soils have a strong ability to support the physiological growth and the yield of S. nigrum. These soils are therefore recommended for the cultivation of this plant. S. nigrum cultivated on these soils was evaluated for proximate compositions, anti-nutrients, vitamins A, C and E and mineral compositions using standard analytical methods. Using the translocation factor, the minerals’ toxicity accumulation levels in the plant were also determined. Accumulation of proximate parameters in the first and second trials are: ash (11.25-12.25 percent and 11.14- 11.54 percent), crude fibre (19.24-19.95 percent and 18.71-19.35 percent), protein (36.72-38.98 percent and 34.47-37.00 percent), phytate (0.84-1.17 and 0.88-1.15 mg/ml), saponnin (94.10-97.00 and 94.17-97.00 percent) and alkaloids (43.03-45.76 and 42.08- 44.10 percent) respectively. Vitamin A ranged between 117 and 137 mg/kg and betweens 108 and 128 mg/kg, vitamin C between 100 and 118 mg/kg and between 96 and 108 mg/kg and vitamin E between 250 and 269 mg/kg and between 227 and 261 mg/kg in the first and second trials respectively. The quantities of macro and micro-nutrients recorded in S. nigrum showed that this plant is a reservoir of nutrients. Plants cultivated on clay loam, silty clay loam and loam soils accumulated elevated nutritients compositions. Investigation was made on the ability of S. nigrum cultivated on different soil texture types to synthesise phytochemicals such as phenol, flavonoid, alkaloid proanthocyanidins, tannins, saponins and antioxidant. Highest concentrations of phenolics (73.87 mg/g), flavonoids (58.41 mg/g), proanthocyanidins (875.74 mg/g), tannins (49.32 mg/g), saponins (875.74 mg/g) and alkaloid (47.50 mg/g) contents were recorded in plant sample cultivated on silty clay loam soil. Also, highest radical scavenging power using DPPH (0.0102 mg/g), ABTS (0.1062 mg/g) and FRAP (0.8395 mg/g) were recorded in plant samples grown on silty clay loam and the next high values were recorded in plant samples grown on clay loam soil. It is showed in this study that silty clay loam soil and clay loam soils are the best soil types for cultivation of S. nigrum for increased antioxidant properties/ oxygen radical scavenging activities. Investigation was made on chemical compositions and antioxidant properties of essential oil extracts of S. nigrum shoot and root cultivated on different soil textures. The Gas Chromatography-Mass Spectrometry (GC-MS) profiling revealed variations in the quality index (QI) and number of chemical constituents of the oil of S. nigrum cultivated on different soil texture types. Geraniol and citronellol were two principal components of high quality common to oil from shoots and roots fromplants cultivated on all soil types. Results of DPPH and ABTS assays of the shoot oil showed that S. nigrum cultivated on clay loam soil had the highest antioxidant power. The presence of citronellol and geraniol among the major compounds is an indicaton of the plant’s role in defensive mechanisms. The work indicated that soil texture has effect on the quality, quantity and chemical compounds synthesised in the shoots and roots of S. nigrum. Antibacterial activities and the efficacy of S. nigrum cultivated on different soil types were carried out on reference strains of 4 gram-positive and 4 gram-negative bacteria. Toxicity evaluation of the plant’s acetone extract and water extract were also assessed on lethality of brine shrimp eggs. Plant water and acetone extracts exhibited strong antibacterial activity against Pseudomona aeruginosa, acetone extracts against Bacillus cereus, Listeria and Escherichia coli. Significantly (p< 0.05) low concentration (0.25 mg/mL) of acetone extracts from plant shoot cultivated on silty clay loam and clay loam soils inhibited B. cereus and P. aeruginosa. Antimicrobial activities of extracts of plant cultivated on clay loam appeared to be more superior to extracs from plants grown on other soil types. Toxicity of the plant extracts (water and acetone) was concentration and time dependent. The LD50 values for all plant extracts were greater than 1000 mg/mL which showed they are non-toxic.
- Full Text:
- Date Issued: 2017
Pharmacological evaluation of phragmanthera capitata (sprengel) balle, loranthaceae :a parasiticmistletoe growing on rubber trees
- Ohikhena, Franklin Uangbaoje
- Authors: Ohikhena, Franklin Uangbaoje
- Date: 2017
- Subjects: Hevea Hevea -- Diseases and pests Rubber
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8899 , 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.
- Full Text:
- Date Issued: 2017
- Authors: Ohikhena, Franklin Uangbaoje
- Date: 2017
- Subjects: Hevea Hevea -- Diseases and pests Rubber
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/8899 , 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.
- Full Text:
- Date Issued: 2017
Pharmacological investigations of Kedrostis africana (L.) Cogn. and Vernonia mespilifolia Less. used in folk medicine in the Eastern Cape, South Africa
- Authors: Unuofin, Jeremiah Oshiomame
- Date: 2017
- Subjects: Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9231 , vital:34307
- Description: The prevalence of obesity and its co-morbidity is increasing in South Africa. High calorie diet, sedentary lifestyle and the cultural belief that being fat or obese signifies beauty, wellness and wealth are major causative factors. This study was undertaken to scientifically validate two major medicinal plants used traditionally in the Raymond Mhlaba Municipality for the mespilifolia Less. were used singly and in combination. According to ethnobotanical studies,these two plants are regarded as wild plants and are only used for medicinal purposes. There has been a dearth of scientific reports on the two plants and to the best of our knowledge, this study is the first to investigate the nutritional, antioxidant, antimicrobial, safety and anti-obesity potentials of the two plants and their combination. This study revealed that both plants are rich in nutrients. K. africana had greater ash (16.28 percent), crude fat (1.12 percent), Ca (2505 mg/100g), Mg (485 mg/100g) and Fe (89.95 mg/100g) while V. mespilifolia showed higher crude fibre (29.24 percent), crude protein (10.75 percent), P (400 mg/100g), Na (570 mg/100g), Cu (1.55 mg/100g) and Mn (4.70 mg/100g). K. africana and V. mespilifolia both contributed 223.37 Kcal/kg and 237.37 Kcal/kg of energy respectively. The polyphenolic evaluation of the acetone, aqueous and ethanol extracts of the plants revealed that the acetone extract of the combination of both plants had higher total phenol (144.59 mgGAE/g) and flavonoid (803.93 mgQE/g) contents, the ethanol extract of the combined plant also had the highest tannin contents (1.25 mgTAE/g), while the acetone extracts of K. Africana had the highest proanthocyanidin content (585 mgCE/g). The antioxidant assays revealed that the ethanol extract for V. mespilifolia had higher scavenging potentials of ABTS, DPPH and vinitric oxide radicals while the aqueous extract of the combination of both had higher scavenging potential for hydrogen peroxide radicals. Evaluation of antimicrobial potential of the extracts using the minimial inhibitory concentration (MIC) assay against 6 bacteria (Actinomyces odontolyticus, Lactobacillus sakei, Staphylococcus aureus, Enterobacter cloacae, Pseudomonas aeruginosa and Bacteriodes thetaiotomicron) and 4 fungi (Candida albicans, Microsporium gypsum, Penicillium chrysogenum and Trichophyton tonsurans) revealed that the plants possess antimicrobial activity. The MIC of the extracts against the tested bacterial strains ranged from 2.5 mg/mL to 5 mg/mL acetone and ethanol extracts of V. mespilifolia and the combined plants as well as the ethanol extracts of K. africana. However, no activity was observed for the acetone extract of K. africana and aqueous extracts of V. mespilifolia and the combination of both plants. Only three fungal strains (Candida albicans, Microsporium gypsum and Penicillium chrysogenum) were susceptible to the organic extracts with an MIC 0.3125 mg/mL to 5 mg/mL while the aqueous extracts showed no activity against all the fungal strains. None of the plant extracts showed any activity against Trichophyton tonsurans. The brine shrimp toxicity test revealed that all the three extracts of V. mespilifolia, aqueous and ethanol extracts of K. africana and aqueous and acetone extracts of the combination of both plants were toxic in relative to Meyer’s index and other indices of toxicity. The cytotoxic effect of the aqueous and ethanol extracts of V. mespilifolia, K. africana and their combination were also evaluated using HeLa cells. From this study, all the extracts tested had IC50 values were greater than 20 μg/mL which connotes that they are not toxic. According to the American National Cancer Institute, crude plant extracts are considered cytotoxic in an in vitro assay when concentrations 20 μg/mL and below produce 50% inhibition of tumor cells, after an exposure time of 48 hours. In vivo acute evaluation of single oral administration of 2000 and 5000/kg body weight did not produce mortality or significant behavioral changes during 14 days observation. In addition, the sub-acute administration of the aqueous extract at 200, 400 and 600 mg/kg/bwt/ day over a period of 28 days revealed no mortality or morbidity. The weekly body and organ weight of the rats were not significantly different from those of the controls and extract treated rats. The aqueous extracts at all doses did not show any significant (p > 0.05) effect on biomarkers of liver and renal damage. Haematological evaluation revealed that oral administration of aqueous extracts of K. africana, V. mespilifolia and the combination of both plants did not induce anaemia or leucocytosis in the animals. Furthermore, histopathological evaluation of the internal organs revealed no detectable inflammation at the the doses administered over a period of 28 days. These results demonstrated that the aqueous extracts of K. africana, V. mespilifolia and the combination of both plants was potentially safe for consumption orally even in chronic administration. Enzyme based in-vitro antiobesity evaluation of the aqueous and ethanolic extracts of K. africana, V. mespilifolia and their combination revealed that the ethanol extracts of both plants and their combination exhibited moderate inhibitory activities against α-amylase, α- glucosidase and pancreatic lipase. However, the standards used for the various inhibition assays exhibited much higher inhibitory actions when compared to any of the extracts. This suggests that the mechanism by which these two plants and their combination exert anti-obesity effects are probably not by inhibition of key enzymes of carbohydrate and fat metabolism.
- Full Text:
- Date Issued: 2017
- Authors: Unuofin, Jeremiah Oshiomame
- Date: 2017
- Subjects: Medicinal plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9231 , vital:34307
- Description: The prevalence of obesity and its co-morbidity is increasing in South Africa. High calorie diet, sedentary lifestyle and the cultural belief that being fat or obese signifies beauty, wellness and wealth are major causative factors. This study was undertaken to scientifically validate two major medicinal plants used traditionally in the Raymond Mhlaba Municipality for the mespilifolia Less. were used singly and in combination. According to ethnobotanical studies,these two plants are regarded as wild plants and are only used for medicinal purposes. There has been a dearth of scientific reports on the two plants and to the best of our knowledge, this study is the first to investigate the nutritional, antioxidant, antimicrobial, safety and anti-obesity potentials of the two plants and their combination. This study revealed that both plants are rich in nutrients. K. africana had greater ash (16.28 percent), crude fat (1.12 percent), Ca (2505 mg/100g), Mg (485 mg/100g) and Fe (89.95 mg/100g) while V. mespilifolia showed higher crude fibre (29.24 percent), crude protein (10.75 percent), P (400 mg/100g), Na (570 mg/100g), Cu (1.55 mg/100g) and Mn (4.70 mg/100g). K. africana and V. mespilifolia both contributed 223.37 Kcal/kg and 237.37 Kcal/kg of energy respectively. The polyphenolic evaluation of the acetone, aqueous and ethanol extracts of the plants revealed that the acetone extract of the combination of both plants had higher total phenol (144.59 mgGAE/g) and flavonoid (803.93 mgQE/g) contents, the ethanol extract of the combined plant also had the highest tannin contents (1.25 mgTAE/g), while the acetone extracts of K. Africana had the highest proanthocyanidin content (585 mgCE/g). The antioxidant assays revealed that the ethanol extract for V. mespilifolia had higher scavenging potentials of ABTS, DPPH and vinitric oxide radicals while the aqueous extract of the combination of both had higher scavenging potential for hydrogen peroxide radicals. Evaluation of antimicrobial potential of the extracts using the minimial inhibitory concentration (MIC) assay against 6 bacteria (Actinomyces odontolyticus, Lactobacillus sakei, Staphylococcus aureus, Enterobacter cloacae, Pseudomonas aeruginosa and Bacteriodes thetaiotomicron) and 4 fungi (Candida albicans, Microsporium gypsum, Penicillium chrysogenum and Trichophyton tonsurans) revealed that the plants possess antimicrobial activity. The MIC of the extracts against the tested bacterial strains ranged from 2.5 mg/mL to 5 mg/mL acetone and ethanol extracts of V. mespilifolia and the combined plants as well as the ethanol extracts of K. africana. However, no activity was observed for the acetone extract of K. africana and aqueous extracts of V. mespilifolia and the combination of both plants. Only three fungal strains (Candida albicans, Microsporium gypsum and Penicillium chrysogenum) were susceptible to the organic extracts with an MIC 0.3125 mg/mL to 5 mg/mL while the aqueous extracts showed no activity against all the fungal strains. None of the plant extracts showed any activity against Trichophyton tonsurans. The brine shrimp toxicity test revealed that all the three extracts of V. mespilifolia, aqueous and ethanol extracts of K. africana and aqueous and acetone extracts of the combination of both plants were toxic in relative to Meyer’s index and other indices of toxicity. The cytotoxic effect of the aqueous and ethanol extracts of V. mespilifolia, K. africana and their combination were also evaluated using HeLa cells. From this study, all the extracts tested had IC50 values were greater than 20 μg/mL which connotes that they are not toxic. According to the American National Cancer Institute, crude plant extracts are considered cytotoxic in an in vitro assay when concentrations 20 μg/mL and below produce 50% inhibition of tumor cells, after an exposure time of 48 hours. In vivo acute evaluation of single oral administration of 2000 and 5000/kg body weight did not produce mortality or significant behavioral changes during 14 days observation. In addition, the sub-acute administration of the aqueous extract at 200, 400 and 600 mg/kg/bwt/ day over a period of 28 days revealed no mortality or morbidity. The weekly body and organ weight of the rats were not significantly different from those of the controls and extract treated rats. The aqueous extracts at all doses did not show any significant (p > 0.05) effect on biomarkers of liver and renal damage. Haematological evaluation revealed that oral administration of aqueous extracts of K. africana, V. mespilifolia and the combination of both plants did not induce anaemia or leucocytosis in the animals. Furthermore, histopathological evaluation of the internal organs revealed no detectable inflammation at the the doses administered over a period of 28 days. These results demonstrated that the aqueous extracts of K. africana, V. mespilifolia and the combination of both plants was potentially safe for consumption orally even in chronic administration. Enzyme based in-vitro antiobesity evaluation of the aqueous and ethanolic extracts of K. africana, V. mespilifolia and their combination revealed that the ethanol extracts of both plants and their combination exhibited moderate inhibitory activities against α-amylase, α- glucosidase and pancreatic lipase. However, the standards used for the various inhibition assays exhibited much higher inhibitory actions when compared to any of the extracts. This suggests that the mechanism by which these two plants and their combination exert anti-obesity effects are probably not by inhibition of key enzymes of carbohydrate and fat metabolism.
- Full Text:
- Date Issued: 2017
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