Development of conservation strategies for Alepidea Amatymbica ECKL. & ZEYH. : a rare medicinal plant in the Eastern Cape, South Africa
- 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:
Effects of Vigna unguiculata and Lablab purpureus on methanogenesis, haematological parameters and the quality of meat from Xhosa Lop Ear goats
- Authors: Washaya, Soul
- Date: 2017
- Subjects: Legumes Forage Forage plants
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/9996 , vital:35249
- Description: The objective of the current study was to evaluate the nutritive value of forage legumes Lablab purpureus (Lablab) and Vigna unguiculata (Cowpea) and their effects on intake, growth, blood parameters and meat quality in Xhosa goats. Forages were established at UFH research farm in the summer of the 2014 /15 growing season in blocks measuring 8m width x 16m long for each legume, replicated three times, making a total of four blocks, and eight treatment units for each legume. Samples were collected at three different stages of growth of preanthesis, anthesis and post anthesis for biomass yield determination. A homogenous sub-sample was then oven dried for 72 hours at 60 0C. After drying the forage samples were milled through a 1mm screen and a 20g sample from each stage of growth and forage sample was subjected to proximate analysis, in-vitro digestibility and anti-nutrient evaluation. The in-vitro digestibility experiment was done with rumen liquor of cattle and sheep collected from an abbatoir. Tannins, total phenolics and sapponins were the only anti-nutrients evaluated as they are perceived to influence methanogenesis in ruminat animals. At 50percent flowering, forage legumes were harvested for hay making which was then used in an in-vivo trial to evaluate the nutritive value of forages. This trial was conducted using eighteen one-year-old goats of average weight 14.2±0.24 kg over a period of sixty days. The results showed that biomass yield, which increased with stage of growth, was significantly higher (P < 0.05) for Lablab than Cowpea (7.968t/ha vs 7.105t/ha). Cowpea exhibited higher moisture content (7.72percent), Ash (13.11percent), acid detergent fibre (ADF) (38.42percent) and crude protein (CP) (20.23percent) than Lablab which had 7.50percent, 11.45 percent, 36.17percent and 19percent, respectively. Lablab forage had significantly higher (P < 0.05) fat content (2.41percent), neutral detergent fibre (NDF) (49.27percent) and hemicellulose (13.07percent) than Cowpea which had 2.1percent; 46.91percent and 8.48percent, respectively. The stage of growth significantly (P < 0.05) affected the mineral content of both forages. Lablab showed significantly higher (P < 0.05) values (1.22percent 0.55percent, 2.67percent) than Cowpea (1.00percent, 0.45percent, 2.30percent) for calcium (Ca), phosphorus (P), and potassium (K) respectively. Lablab forage had significantly higher (P < 0.05) tannin (3.345mgCAE/gDM), phenolic (13.47mgGAE/gDM) and saponin (0.75percent) content compared to Cowpea with values of 1.494mgCAEg/DM; 9.402mgGAE/gDM and vs 1.55percent respectively. The tannin content significantly influenced in-vitro digestibility and enteric methane production. The forage type, harvesting stage and inoculum source significantly (P < 0.05) affected the in-vitro digestibility of the forages. The in-vitro dry matter (IVDM) and in-vitro organic matter (IVOM) digestibility was significantly higher (P < 0.05) for Lablab (41.13percent; 39.63percent) than Cowpea (39.86percent; 19.44percent), respectively. Both forages recorded higher dry matter (DM) digestibility coefficients at anthesis stage of growth 61.58percent, and 51.5 percent for Lablab and Cowpea respectively. The IVOM digestibility increased with stage of harvest (23.7percent to 25.57percent) for Cowpea while Lablab showed a decrease (44.6 percent to 43.9percent) when cattle inoculum was used. The IVDM digestibility was higher (P < 0.05) for Lablab (50.5percent) when cattle inoculum was used while Cowpea was observed to have higher digestibility co-efficiencies (38.54percent) when sheep inoculum was used. Cowpea had lower (P < 0.05) IVOM digestibility than Lablab (19.44percent) vs. 39.6percent). Lablab exhibited higher (P < 0.05) metabolisable energy (ME) values than Cowpea (6.21 vs. 2.70 MJ/kgDM). In the feeding study, the total DM intake by goats for Lablab was higher (P < 0.05) compared to Cowpea (688.1 vs. 607.8 g/head/ day). There was a positive (P < 0.05) correlation between dry matter intake and average daily gain (r= 0.8513, and r=0.5279) for Cowpea and Lablab respectively. Lablab and Cowpea promoted growth of Xhosa goats at a rate of 35.0g/d; and 38.3g/d, respectively which was not significantly different (P > 0.05). However, this growth was associated with a significantly higher (P < 0.05) food conversion ratio (FCR) of 19.16 vs 18.11 for Cowpea and Lablab, respectively. The apparent DM, non structural carbohydrate (NSC) nutrient digestibilities were significantly different (P < 0.05) for Lablab and Cowpea. Furthermore sex of animal influenced significantly (P < 0.05) the DM, ADF, NSC and NDF digestibilities. Lablab and Cowpea did not influence (P > 0.05) individual VFA molar concentrations in both sexes. However, animals fed Lablab had significantly higher butyrate concentrations (P < 0.05). Lablab and Cowpea forages significantly lowered (P > 0.05) enteric methane production in goats compared to a concentrate diet, and this was related to animal activity. Animals produced significantly more (P < 0.05) methane gas when ruminating than feeding or just standing. The average methane produced each year was lower but not significant (P > 0.05) for animals fed Cowpea than Lablab (4.602kg CH4, vs. 4.719kg CH4) when expressed per year. Male animals produced more gas than females with values of 17.40L/day; 12.46 g/kg DMI and 0.126g/day vs. 15.47L/day, 12.28 g/kg DMI, and 0.0109g/day, respectively. Forage legumes had no significant effects (P > 0.05) on serum total proteins (TP), globulin, urea, creatinine, alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma- glutamyl transferase (GGT) concentrations, but serum concentration of albumin was influenced by the diets (P < 0.05). Sex of animals significantly influenced ALP concentration (P < 0.05) with male animals exhibiting higer ALP values than females. Measured over time, the plasma concentration of urea and ALP significantly increased (P < 0.05) while creatinine and cholesterol concentration decreased (P < 0.05). Although the overall serum concentration of urea, total proteins, globulin, creatinine, ALT, ALP and GGT remained unchanged among the treatments and between sexes; treatment by sex, treatment by day and sex by day interactions were significant (P < 0.05). The white blood cell (WBC), red blood cell (RBC), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), haemoglobin, haematocrite, platelet and mean platelet volume (MPV) levels were similar among treatments and between sexes (P > 0.05). The WBC decreased with time by 8.07 x10 9/l while mean crepuscular volume (MCV) increased by 11.83(fl) from day 15 to day 55. Treatment diets significantly (P < 0.05) influenced neutrophile (percent) content while sex influenced basophile (percent) content. There were no treatment or sex effects (P > 0.05) on lymphocytes (percent), monocytes (percent) and eosinophiles (percent). In the meat quality study, the dietary treatments and sex had a significant (P < 0.05) effect on dressing out percent (DPpercent), initial pH, redness (a*), yellowness (b*), Warner Blartze Shear force (WBS) , drip loss and cooking loss in the chevon from Xhosa goats. Compared with a commercial pellet diet, Lablab and Cowpea diets resulted in similar slaughter body weights (SBW), hot carcass weight (HCW) and cold dressed mass (CDM) of carcasses. However, female animals exhibited a significantly (P < 0.05) higher DPpercent than male animals (42.3percent vs. 38.9percent) for all treatments. The male animals exhibited significantly (P < 0.05) higher pH values one hour after slaughter than females (5.79 vs 5.67). Neverthreless the diet and gender did not significantly (P > 0.05) affect the ultimate pH (pHu). Meat samples from male animals had significantly (P < 0.05) higher redness values than females. Feeding cowpea significantly (P < 0.05) increased meat redness with the least drip loss of chevon. Female animals produced significantly (P < 0.05) tougher chevon compared to male animals; 4.16kg and 3.36kg for female and male, respectively. Lablab and Cowpea posses high CP levels and moderately lower NDF with high ADF values that influences dry matter intake (DMI), digestibility and growth of goats. These forage legumes meet animal requirements for fat, ADF, NDF, CP, Ca, Mn, zinc and Cu and their biomass yield is satisfactory.
- Full Text:
Market participation and value chain integration among smallholder homestead and irrigated crop farmers in the Eastern Cape province of South Africa
- Authors: Mdoda, Lelethu
- Date: 2017
- Subjects: Farms, Small -- South Africa -- Eastern Cape Irrigation farming -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/15023 , vital:40152
- Description: The irrigation schemes had been established over the years and now are operational but there is no marked improvement in the living conditions of the rural farmers and households. Smallholder farmers still face numerous constraints in market participation that hinder smallholder farmers, irrigators and homestead growth which have been attributed to lack of access to markets and technical expertise. Despite the government efforts, smallholder farmers effectively functioning in the agro-food chains, high-valued markets and commercial agricultural markets are rare; this indicates that the objective to allow smallholder farmers to advance their livelihood through participating in commercial agro-food chains has not yet been met. Farmers in the Eastern Cape produce many crops which they mainly sell in informal local markets; there is minimal number of smallholder farmers supplying their produce to the formal markets. Irrigation development is very crucial to the development of the agricultural sector as it ensures improvement in yields and reduces rural poverty through creating rural employment, enhance smallholder farmers’ market participation and enhance market access policies by smallholder farmers as means to achieve the Sustainable Development Goals The study was conducted in the Eastern Cape Province and employed survey data obtained from 200 smallholder irrigated crop farmers and homestead gardeners. A multistage stratified sampling procedure was used in which the first stage involved selecting the study areas. This was followed by the selection of the district and then the respondents. The farmers were selected from three District Municipalities which have operational irrigation schemes, namely OR Tambo, Amathole and Chris Hani District Municipalities in the province. STATA and SPSS were used to analyze the data. The Heckman model was applied to examine factors influencing farmers’ decision to participate in market among crop producing farmers in the province. In the first stage Heckman analysis, the decision as to whether or not to participate (which is a binary choice situation) is used to undertake the maximum likelihood estimation (MLE). In the second stage, the conditional quantity sold (continuous variable) is assumed to follow a truncated normal regression model, whereby the MLE is estimated by fitting a truncated normal regression of quantity sold. Gross Margin and Net Farm Income were used to measure farm profit as well as multiple regression analysis to estimate determinants of profitability in the study area. Profit efficiency was measured using the normalized transcendent logarithmic profit frontier approach (translog). he descriptive statistics employed include means, percentages and frequencies mostly of the socio-economic characteristics of farmers in the study area. The results show that males were dominant with the representation of 61.7percent. The majority of farmers were aged and the mean age was 60 years, indicating that farmers in the province are old which has implication for productivity and market participation. High level of illiteracy is shown in the data and mean household size of 5 persons with the household head having at least obtained some primary school education.The irrigated crop farmers and homesteads were found to have farm size under 4 ha. About 86.5percent were full time farmers and Farming is their major source of livelihood. Smallholder irrigators and homestead gardeners derive their income from social grants and remittances. This thesis found out that majority of the farmers do not participate in markets. In this instance, farming becomes a scapegoat for failure to enter alternative labour markets. The average annual on-farm production income from smallholder irrigators was R7 860.27 and homestead gardeners was R5 915.50. The empirical results from probit model suggest that age of the farmer, level of education of the farmer, household size, farm organization, access to extension, distance to markets, occupation and farm experience were some of the key determinants that had significant and positive effects on farmers’ decision to participate in markets while access to credit, transport to the markets and farm size were some of the key determinants that had significant and negative effect on farmers’ decision to participate in markets. The volume of crops sold to the market is determined by gender, age, years spent in school, distance to the market, farm experience, household size, access to extension, membership in farm organization and non-farm income.
- Full Text:
Ruthenium sulphide nanoparticles derived from tri-dithiocarbamato ruthenium (III) complexes : synthesis, optical and structural studies
- Authors: Mbese, Johannes Zanoxolo
- Date: 2017
- Subjects: Nanoparticles Ruthenium compounds
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/15420 , vital:40406
- Description: The present Thesis pioneer the application of single-source molecular precursor method for the synthesis of ruthenium sulfide nanoparticles using a series of novel self-prepared single-source molecular precursors. The preparation of precursors involved the design and synthesis of compounds containing all the desired elements required within the coordination compound. Good precursors are tailored to give reproducible, clean decomposition at moderate temperatures, leading to high quality, defect free, mono-dispersed nanoparticles. Nine (9) homonuclear tris-dithiocarbamato ruthenium(III) complexes, [Ru(S2CNR2)3] were prepared from a stoichiometric reaction of RuCl3·H2O with self-prepared dithiocarbamate ligands at room temperature in a molar ratio of Ru3+: Ligand of 1:3. Dithiocarbamate ligands were derived from a stoichiometric reaction of carbon disulfide with (aniline, N-allylmethylamine, p-toluidine, p-anisidine, N-ethyl-m-toluidine, piperidine, morpholine, di-isopropylamine, and diallylamine) in the presence of concentrated ammonia or potassium hydroxide in ice cold bath. The dithiocarbamate ligands and complexes were characterized by elemental analyses, UV-Vis, Fourier transform infrared spectroscopy (FTIR), 1H- and 13C-NMR spectroscopy. Thermogravimetric analyses (TGA) was used to study the decomposition profiles of the precursor complexes. The results obtained from the TGA of precursors showed that the complexes decompose to ruthenium sulfide nanoparticles. The FTIR spectra of the ligands revealed prominent strong absorption bands ascribed to v(N-H) stretching vibrations and also confirm the bidentate coordination of the dithiocarbamate ligands. Ruthenium(III) complexes show absorption spectra in the visible region that exhibit bands attributed to n → π* electronic transitions located on the sulfur atoms located in the S–C–S and N–C–S chromophores of the bidentate dithiocarbamate ligands respectively. The absorption spectra also confirmed the geometry of ruthenium(III) complexes to be octahedral. The proposed structures of dithiocarbamate ligands and ruthenium(III) complexes were confirmed by the 1H- and 13C-NMR. The complexes were used as single-source molecular precursors for the synthesis of ruthenium sulfide nanoparticles. The structural and optical properties were studied using transmission electron microscope (TEM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), UV-Vis absorption and photoluminescence (PL) spectra. FTIR revealed that Ru2S3 nanoparticles are capped through the interaction of the –NH2 group of hexadecylamine HDA adsorbed on the surfaces of nanoparticles and it also showed that oleic acid (OA) is acting as both coordinating stabilizing surfactant and capping agent. The XRD confirmed the successful formation of Ru2S3 nanoparticles induced by the thermal decomposition of series of [Ru(S2CNR2)3] complexes. The diffraction peaks: 2θ = 29.43, 40.54, 49.33, 51.86, 61.92, and 75.94 were assign the Miler indices (hkl) to be (111), (211), (220), (300), (222) and (330) reflections, respectively, and were found to be in agreement with a cubic crystal structure reported in database file of (JCPDS 19-1107). The particle sizes estimated from Scherer's equation were found in a range between 2.5 and 4.9 nm. EDS spectra reveal that the prepared nanoparticles are mainly composed of Ru and S, confirming the presence of Ru2S3 nanoparticles in cubic phase. The inner morphology of nanoparticles was obtained by transmission electron microscopy (TEM) and most nanoparticles had narrow particle size distribution characterized by an average diameter of 8.45 nm with a standard deviation of 1.6 nm. The optical band gap (Eg) determined from Tauc plot was found in the range (3.44 to 4.18 eV) values.
- Full Text: