198 research outputs found
Rights and risk : challenging biotechnology policy in Zimbabwe
Human rights have become a key focus of law and development, yet they remain conspicuously absent from the regulatory and policy regimes for the use and development of modern agricultural biotechnology. In contrast to rights approaches biotechnology law and policy is concerned with individual property rights and global trade. In this context the only “acceptable” restriction on biotechnology development is safety and thus regulation has focussed almost exclusively on risk assessment. Drawing on the experience of Zimbabwe and other countries in southern Africa, this paper argues that a risk-based approach, creates an artificial divide between civil and political rights and economic, social and cultural rights, desegregates society into a conglomerate of individual rights holders, effectively dis-empowers citizens and fails to create a viable and supportive legal framework for consensual agricultural biotechnology development that is responsive to local needs and perceptions about rights.
The paper begins by examining the legal underpinnings of a risk-based approach and asks why it has come to prominence. It contrasts this with a rights approach and looks specifically at how rights framing and claiming has evolved since Zimbabwe’s independence in 1980. Against this background it examines demands for rights to participation, livelihood choice, farmer and community property and information and how these are manifested as challenges to the established regulatory regime. In particular it looks at issues of problem framing, knowledge, culture, values, information and responsibility. In conclusion the paper suggests that human rights law is a useful tool in creating more socially responsive law. This is so because it seeks to redress inequalities by establishing legal standards that allow for the restoration of human dignity by putting people back in control of their lives and limiting abuse and so creating substantial equality between people
Gender and Indigenous Knowledge Systems and Sustainable Development
A ZLRev article on gender and Indigenous Knowledge Systems (IKS) in Zimbabwe.Environmental education is essential for promoting sustainable development practices and strategies. Potentially, it may affect the choices various stakeholders, policy makers and managers make that affect the environment. Further, it is important for enforcement of the law in that it could affect the decisions the police make about prosecuting and their efficiency. Similarly, the perspective of the court affects how they interpret the law and their sentencing practice.* 1
Sound policy, programme formulation processes, planning and managerial practice that are able to address the social, economic and environmental objectives of sustainable development are essential. It is important for environmental education initiatives to challenge views currently held by policy makers, planners and enforcement agencies as well as to complement their knowledge base so as to promote better planning and management. Both Indigenous Knowledge Systems (IKS) and gender are sorely neglected factors in decision making and policy formulation. This may be attributed to many factors including Zimbabwe's political history, existing gender relations, the institutional framework and the planning and managerial framework. This paper examines the significance of gender and IKS in the creation of such strategies. It seeks to locate rural women in the development scenario and to specifically identify their interests and values. Thus, it explores the relationship of rural women to knowledge systems and defines them as critical stakeholders
Isolation of an antibacterial stilbene from Combretum woodii (Combretaceae) leaves
Acetone extracts of C. woodii leaf powder was separated by solvent-solvent partition into six fractions. The highest total activity was in the chloroform fraction. This fraction contained mainly one compound active against S. aureus. This compound was isolated by bioassay-guided fractionation using silica gel open column chromatography and identified by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) as the stilbene 2’,3’,4-trihydroxyl-3,5,4’-trimethoxybibenzyl (combretastatin B5) previously isolated from the seeds of C. kraussii. It showed significant activity against S. aureus withan MIC of 16 mg/ml but with lower activity towards P. aeruginosa (125 mg/ml), E. faecalis (125 mg/ml) and slight activity against E. coli. This is the first report of the antimicrobial activity of combretastatin B5. Its concentration in the leaves was in the order of 5-10 mg/g which makes the use of non-polar leafextracts a viable proposition in treating some infections, particularly in resource-poor settings
Combretum woodii (Combretaceae) leaf extracts have high activity against Gram-negative and Gram-positive bacteria
Dried ground leaves of Combretum woodii were extracted with 10 different solvents (hexane, diisopropyl ether, diethyl ether, methylene dichloride, ethyl acetate, tetrahydrofuran, acetone, ethanol, methanol and water) to determine the best extractant for subsequent isolation and characterization of antibacterial compounds. With the exception of the water extract, which had no antibacterial activity, the other extracts were bioactive with at least one of them exhibiting minimum inhibitory concentration values of 0.04 mg/ml against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli or Enterococcus faecalis. Intermediate polarity solvents extracted c. 10% of the dry mass compared to c. 3% with the more polar or non-polar solvents. These solvents also had higher antibacterial activity than more polar or non-polar extractants. Ethyl acetate was the best extractant with an average minimum inhibitory concentration (MIC) value of 0.08 mg/ml for the four pathogens followed by acetone and methylene dichloride with values of 0.14 mg/ml. The average MIC values for the positive controls were 0.13 (ampicillin) and 0.12 mg/ml (chloramphenicol). By taking the quantity extracted from the leaf powder into consideration, the total activity, a measure of potency, was highest for methylenedichloride (1309 ml/g) followed by acetone (1279 ml/g) extracts. The antibacterial activity was high enough to consider the use of extracts for clinical application and to isolate and characterise antibacterial compounds from the extracts. Based on the Rf values of the antibacterial compoundsdetermined by bioautography, the antibacterial compound was not a polyphenol or a tannin
Rights Mapping (Policy Brief)
Changes in resource entitlements can disrupt existing social relationships and intensify inequality. When this happens it can trigger or amplify conflict. The risk of conflict is higher when one group becomes privileged over another, or where existing inequities and inequalities are exacerbated. Mapping rights can help avoid increases in conflict dimensions, as such mapping increases the visibility of rights of communities, as well as within and among communities. Rights mapping can be used to avoid conflicts by supporting local and indigenous people and those involved in decision-making to actively guard against rights erosion that increase vulnerability
A comparative study of antibacterial activities of wild and cultivated plants used in ethnoveterinary medicine
Farmers generally collect fresh plant materials from the wild for ethnoveterinary uses. They are encouraged to harvest with caution and dry or cultivate important materials in order to protect the biodiversity. These recommendations are not validated scientifically. The microplate method for minimum inhibitory concentration (MIC) determination was used to compare wild with cultivated, and fresh with dry plant materials. The MIC values obtained ranged from 1.25 to 0.01 mg/ml. MIC values ≤0.3 mg/ml were considered as cut off point between effective and none effective inhibition. The multilevel linear models (hierarchical linear models), both unadjusted and adjusted models were employed. The plant (name) was considered as level-2 or higher level, while the actual observation was level-1 or lower level. The crude estimates of the odds ratio indicated that wild is significantly 0.57 times less likely than garden to yield MIC values of more than 0.3 mg/ml (p-value = 0.005). Also, fresh are about 4.195 times more likely than dry to yield MIC scores of more than 0.3 mg/ml (p-value < 0.001). Adjusting for conditions “dry and fresh”, microbe and solvent; wild is significantly 0.52 times less likely than garden to yield MIC values of more than 0.3 mg/ml (p-value = 0.003). On the other hand, when adjusting for “wild or garden”, type of solvents and type of microbes; fresh is significantly 4.202 times more likely than dry to yield MIC values of more than 0.3 mg/ml (p-value < 0.001). These results partially support farmers claiming that wild plant materials are more potent than the grown ones. On the contrary, the results are in favour of drying plant materials.Key words: Antibacterial, medicinal plants, wild, cultivated, fresh, dry, odd ratio
Towards the Constitutional Protection of Environmental Rights in Zimbabwe
A ZLRev. article on the legally constituted rights for the protection of the environment and ecology of Zimbabwe.The increasing emphasis on environmental protection and ecological preservation, as well as Zimbabwe's crisis of development make it eminently desirable to analyse the conceptual values in which environmental law is based. It has been stressed that environmental law derives from the common interest of mankind, as does international recognition of human rights and freedom. It is thus normal that a link was established between the two as early as 1972, by the Stockholm Declaration itself which stated that:
Man (sic) has the fundamental rights of freedom, equality, and adequate conditions of life, in an environment of a quality that permits a life of dignity and well being, and he bears a solemn responsibility to protect and improve the environment for present and future generations.’
Thus, "the right to environment" was proclaimed at the beginning of the "environmental era" at a worldwide level. In addition, as it is formulated, this principle includes all the essential elements of both old and new fields of international law. It is very clearly linked with human rights, civil, political (freedom, equality, dignity) economic, social and cultural rights (adequate conditions of life, well being). It also warns that everybody has a responsibility for the protection and improvement of the environment. Finally, and this is new in human rights language, it also opens a time perspective by speaking of future generations
The use of Clausena anisata in insect pest control in Africa : a review
ETHNOPHARMACOLOGICAL RELEVANCE : Clausena anisata is used traditionally by various communities across Africa against pests such as mosquitoes, flies and weevils among others. Pests are a major cause of disease and production losses in various crop and livestock production systems in Africa. This review discusses the available information on the occurrence, chemistry, biological activity and possible commercialization of Clausena anisata with a view to see the plant species being integrated in pest management. MATERIALS AND METHODS : Information on the ethnomedical use, chemistry and biological activity of C. anisata published between 1980 and 2016 was accessed from various databases namely Science Direct, Springer Link and Wiley Online Library. In addition various relevant books were also consulted. RESULTS : The crude extracts as well as different fractions of C. anisata have been evaluated for activity against
various insect pests and have been shown to be active. Furthermore, close to 50 compounds have been isolated and identified from C. anisata, which include coumarins, carbazole alkaloids, limonoids and essential oils (monoterpenes). Some of these compounds have been proven to exhibit pesticidal properties in both laboratory and field studies against various pests including mosquitoes, flies and weevils. The possible mechanisms of action of these compounds have been explored in this review. CONCLUSION : The results of pesticidal and hytochemical screening of C. anisata strongly indicate that the species is endowed with pesticidal properties that can be harnessed into commercial products. However, one glaring challenge in the evaluation of this plant species for pesticidal activity has been the non-availability of standard testing systems. Researchers have used various methods which they developed based on their own circumstances and resources. Formulation, standard appropriate testing systems and agronomic research are key in unlocking the potential of this important African species.The National Research Foundation of South Africa (NRF) (Grant No. 95408)http://www.elsevier.com/locate/jethpharm2017-12-31hb2017Paraclinical Science
Annona stenophylla aqueous extract stimulate glucose uptake in established C2Cl2 muscle cell lines
Background: Annona stenophylla is a folk medicine popularly used in Zimbabwe for the treatment of many ailments. This study was carried out to determine some of the possible anti diabetic mechanisms of its action using in vitro cell culturing methods.Methods: A. stenophylla’s effects on glucose uptake were tested using muscle cells (C2Cl2). Expression of glucose 4 transporters was determined by treating cell lines with plant extract. Total RNA was isolated and using RT-PCR, GLUT 4 expression levels were quantified. Translocation of GLUT 4 was assessed using FITC fluorescence measured by flow cytometry.Results: Treatment of cells with plant extract significantly increased glucose uptake in a concentration dependent manner, with the highest concentration (250 μg/ml) giving 28% increased uptake compared to the negative control. The increase in glucose uptake (2.5 times more than control) was coupled to increase in GLUT 4 mRNA and subsequently GLUT 4 translocation. Wortmannin expunged the A. stenophylla induced increase in GLUT 4 mRNA and glucose uptake.Conclusion: The results suggest that A. stenophylla aqueous extract increases glucose uptake partly through increasing the GLUT 4 mRNA and translocation potentially acting via the PI-3-K pathway. This study confirms the ethnopharmacological uses of A.stenophylla indicating potential for anti-diabetic products formulation.Keywords: Annona stenophylla, glucose uptake, GLUT 4, diabetes, wortmannin
Antifungal activity of epithelial secretions from selected frog species of South Africa
Resistance to antibiotics has been acknowledged as a major global public health problem. The use of antimicrobial peptides to provide alternatives to combat multi-drug antibiotic resistance is beginning to attract increasing attention. The high diversity of amphibian skin peptides renders anurans an important potential source for the discovery of novel pharmacophores. This study aimed to investigate the antifungal activity of skin secretions from selected frogs (Amietia fuscigula, Strongylopus grayi and Xenopus laevis) and one toad (Amietophrynus pantherinus) of the south Western Cape Province of South Africa. Initially, different extraction techniques for the collection of skin secretions were tested and optimized, thereafter the extracts were tested against three fungal species of medical and agricultural importance that is, Candida albicans, Fusarium verticillioides and Aspergillus flavus. Chemical stimulation gave the best yield by mass, and secretions from A. fuscigula showed the best activity with an MIC of 40 ÎĽg / ml against C. albicans and 200 ÎĽg / ml against A. flavus. In general, C. albicans and A. flavus were the most sensitive while F. verticillioides was the most resistant. From this study it appears that bioprospecting of South African frog species has the potential to yield potential therapeutic lead agents.Key words: Antifungal, African anurans, antimicrobial peptides (AMP), Candida albicans, Aspergillus flavus, bioprospecting, minimum inhibitory concentrations (MIC)
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