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Abstract: In this report, we present preliminary nutritional data for traditional leafy vegetables collected in Kwa Zulu-Natal, South Africa, including their content of mineral elements (Ca, P, Na, Zn, Mg, Mn and Fe) and antioxidant levels. Twenty vegetables were studied: Amaranthus dubius, Amaranthus hybridus, Amaranthus spinosus, Asystasia gangetica, Bidens pilosa, Centella asiatica, Ceratotheca triloba, Chenopodium album, Cleome monophylla, Cucumis metuliferus, Emex australis, Galinsoga parviflora, Justicia flava, Momordica balsamina, Oxygonum sinuatum, Physalis viscosa, Portulaca oleracea, Senna occidentalis, Solanum nodiflorum and Wahlenbergia undulata. The results of this study provide evidence that these local traditional vegetables, which do not require formal cultivation, could be important contributors to improving the nutritional content of rural and urban people. From this study, it was determined that twelve leafy vegetables, namely A. dubius, A. gangetica, A. hybridus, A. spinosus, C. metuliferus, C. monophylla, C. triloba, G. parviflora, J. flava, M. balsamina, P. viscosa and W. undulata provide mineral concentrations exceeding 1% of plant dry weight and are much higher than typical mineral concentrations in conventional edible leafy vegetables; they are thus recommended for future commercial cultivation. High levels of antioxidant activity (96%) were noticed in J. flava and P. oleraceae. [Copyright &y& Elsevier]

Traditionally brewed alcoholic beverages are regularly consumed by most ethnic black South Africans. Maize and barley, both of which are used for producing locally brewed alcoholic beer, are frequently contaminated by mycotoxin-producing moulds. The study was undertaken to investigate whether these toxins are present in raw grains and the traditional beers imbibed by the local black African population. It was established that the raw ingredients (sorghum, sorghum malt grains, maize grits), commercially produced traditional beers (Utshwala and Utshwala special) and home-brewed beers (Umqombotha, Isiqatha, Imfulamfula) were contaminated by bacteria and fungi (both yeasts and moulds). The contaminating moulds were isolated and identified. The contaminated samples were analysed for aflatoxins B[sub 1], B[sub 2], G[sub 1] and G[sub 2], zearalenone, citrinin, deoxynivalenol, and ochratoxin A using a multi-mycotoxin thin-layer chromatography screening method and the toxins were quantified by high-performance liquid chromatography. Grain samples were infected by Aspergillus flavus, A. alliaceus, A. clavatus, Penicillium spp., Rhizopus spp. and Mucor spp. Sorghum malt grain samples contained the toxin zearalenone. No mycotoxin-producing fungi were present in the fermented beers but two of six commercial beer samples contained aflatoxins (200 and 400 μgl[sup -1]) and 45% (13 of 29) of the home-brewed beers had zearalenone (range 2.6-426 μg l[sup -1]) and/or ochratoxin A (3-2340 μg l[sup -1]). [ABSTRACT FROM AUTHOR]

Extracts of selected flowering plants, which are considered eco-friendly, are used for the treatment of numerous ailments and vector control worldwide. This has resulted in approximately 25 per cent of currently used drugs being derived from herbal sources. The aqueous and methanolic extracts of twelve plant species, Psidium guajava (pink fruit), Psidium guajava (white fruit), Psidium cattleianum var. cattleianum, Psidium guineense and Psidium X durbanensis, Achyranthes aspera, Alternanthera sessilis, Guilleminea densa, Capparis tomentosa, Leonotis leonurus, Dichrostachys cinerea and Carpobrotus dimidiatus, were tested for insecticidal activity, including larvicidal, adulticidal and repellent activities against the adult female mosquito, Anopheles arabiensis. The extracts of P. guajava (white fruit), C. tomentosa, L. leonurus,D. cinerea, and C. dimidiatus exerted a pronounced inhibitory effect on adult insects, while those of P. guajava (pink fruit), P. X durbanensis, P. cattleianum var. cattleianum, P. guineense, A. aspera, A. sessilis, and G. densa were ineffective and failed to satisfy the criteria set by the World Health Organization. In the tests for repellency against An. arabiensis, all the tested aqueous and methanolic plant extracts except those of A. sessilis repelled 80-100% of mosquitoes. The most effective mosquito repellents were the methanol and aqueous extracts of P. guajava (pink fruit), P. X durbanensis, P. cattleianum var. cattleianum, P. guineense, G. densa,L. leonurus and D. cinerea, which are potential sources of cost effective mosquito repellents to be utilized in malarial endemic areas.

Phytoremediation is an emerging technology where specially selected and engineered metal-accumulating plants are used for bioremediation. This study was undertaken to evaluate the potential of Amaranthus dubius for phytoremediation of chromium (Cr), mercury (Hg), arsenic (As), lead (Pb), copper (Cu) and nickel (Ni). Locally gathered soil and plants of A. dubius were investigated for the metals from a regularly cultivated area, a landfill site and a waste water treatment site. Metals were extracted from the samples using microwave-digestion and analyzed using Inductively Coupled Plasma-Mass Spectroscopy. The mode of phytoremediation, effect of the metals on the plants, ability of the plant to extract metals from soil (Bioconcentration Factor) and the ability of the plants to move the metals to the aerial parts of the plants (Translocation Factor) were evaluated. The survey of the three sites showed that soils were heavily contaminated with Cr, Hg, Cu and Ni. These levels were far above acceptable standards set for soils and above the standards set for the Recommended Dietary Allowance. Specimens of A. dubius from the three sites showed that they could tolerate Hg, sequester it from the soil, and translocate it to the shoots. Cr could only be removed from the soil and stored in the roots, with limited amounts translocated to the aerial parts. Pb, As, Ni, and Cu have some degree of transportability from the soil to the roots but not to aerial parts. The ability of A. dubius to be considered for phytoremediation has to be viewed with caution because translocation of the metals to the aerial parts of the plant is limited.