Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4

The effect of different tillage systems on the yield and incidence of root and stalk rot of sorghum

The effect of different tillage systems on grain yield, root and stalk rot of sorghum (Sorghum bicolor (Moensch) L) was studied over four seasons at Potchefstroom. Seasonal effects were apparent for all parameters, indicating significant environmental effects. Tillage treatments had no significant effects on grain yield and root and stalk rot of sorghum. Positive correlations existed between grain yield and root rot at the soft dough stage and root rot and stalk rot at soft dough and harvest.L'effet de plusieurs systemes appliques sur le rendement de grain, racine et tige du sorgho (Sorghum bicolor) etait etudie pendant quatre saisons a Potchfstroom. Les effets saisonniers etaient presque apparents au niveau de tous les Parametres, indiquant les effets considerables de l'environement. Les traitements pendant la culture n'ont pas eu des effets considerables sur les rendements des grains, racines et tiges du sorgho. Les correlations positives ont existe entre le rendement des grains, racines et tige pendant le stade doux du ble et la recolte

Occurrence of aflatoxins and aflatoxin-producing Aspergillus spp. associated with groundnut production in subsistence farming systems in South Africa

Anatoxins are carcinogenic mycotoxins produced by Aspergillus spp. In groundnut kernels. Forty-six groundnut samples were collected from subsistence farmers In three provinces of South Africa, namely KwaZulu-Natal (KZN), Mpumalanga (MP) and Limpopo (LP), in 2006 and 2007. Anatoxin levels of groundnut kernels were quantified using an ELISA technique. The occurrence of A. parasiticus colonies was predominant and it was isolated at twice the frequency of A. flavus. Anatoxins were present in groundnut produced in the northern parts of KZN, where aflatoxin levels of up to 131 parts per billion (ppb) were found. In Mpumalanga and Limpopo, the highest aflatoxin levels were 160 ppb and 2 ppb, respectively. In the Makhanisi and Mbazwane localities situated in KwaZulu-Natal, and in Boshoffontein in Mpumalanga, aflatoxin levels were higher than the maximum permitted level set by the Food and Drug Administration in the USA (20 ppb), the European Union (6 ppb) and the Department of Health in South Africa (10 ppb) for groundnut that is Intended for direct human consumption. This study indicates the need for mycotoxin awareness campaigns and control programs to be implemented in rural areas of South Africa.Articl

Stenocarpella maydis and its toxic metabolites: a South African perspective on diplodiosis

Stenocarpella maydis is one of the most prevalent ear and stalk rot pathogens of maize globally, causing reductions of grain quality and yield. Various molecular methods, including polymerase chain reaction (PCR)-based techniques and nucleotide microarrays, have been developed for the identification of S. maydis infestation in maize grain. In addition to diplodiatoxin, new metabolites, namely dipmatol, diplonine and chaetoglobosins K and L, have been isolated from S. maydis infected cultures. S. maydis infected maize is also associated with intoxication in ruminants. Diplodiosis, a nervous disorder of cattle and sheep, results from ingestion of mouldy ears, kernels and maize stubble infected by S. maydis. Although this disease is most common in southern Africa, it has also been reported in Australia, Argentina and Brazil. Diplodiosis is characterised by reluctance of the animals to move, a wide-based stance, incoordination, paralysis and death. Myelin degeneration (status spongiosis) is the only histopathological change observed in affected animals, especially in cases of perinatal mortality. To date, none of the purified S. maydis metabolites has been administered to ruminants in order to reproduce diplodiosis. However, recent studies have focused on investigating the toxicity of the metabolites on cell cultures. Cytotoxicity studies where cultured cells were exposed to the S. maydis metabolites indicated that diplodiatoxin and dipmatol affected the activity of the mitochondrial succinate dehydrogenase enzyme and the overall viability of the cells. More detailed in vitro toxicity studies are still required to elucidate how the currently available S. maydis metabolites influence parameters such as the mechanism of cell death. Development of analytical test methods to quantify and establish the presence and distribution of these mycotoxins in infected maize commodities also needs investigation. It is also critical that the role of S. maydis stalk rot be evaluated as a potential source and cause of diplodiosi

Fusarium spp. and levels of fumonisins in maize produced by subsistence farmers in South Africa

Fusarium spp. produce fumonisins - mycotoxins that are of importance to maize production in South Africa. Fumonisins have been associated with human oesophageal cancer and cause various diseases in animals that are of concern to the animal feed industry. Maize samples, collected from subsistence farm fields in the Eastern Cape, KwaZulu-Natal, Limpopo and Mpumalanga provinces of South Africa during the 2006 and 2007 growing seasons, were analysed for Fusarium spp. and contamination with fumonisins. Fusariumverticillioides was the most common Fusarium species in maize followed by F. subglutinans and F. proliferatum. Levels of contamination with fumonisins ranged from 0 µg/g to 21.8 µg/g, depending on the region where samples were collected. Levels of fumonisins were highest in northern KwaZulu-Natal (Zululand) where 52% and 17% of samples collected in 2006 and 2007, respectively, exceeded 2 µg/g. Regression analyses showed a positive correlation between fumonisin-producing Fusarium spp. determined by real-time polymerase chain reaction and concentration of fumonisins (r = 0.93). Many samples from Zululand, and some from Mokopane (Limpopo) and Lusikisiki (Eastern Cape), contained fumonisins at levels well above the maximum levels of 2 µg/g set by the Food and Drug Administration (USA) and therefore also the limit of 1 µg/g set by the European Union for food intended for direct human consumption. Regulations governing contamination of grain with fumonisins are not yet implemented in South Africa. The high incidence of fumonisins in subsistence farming systems indicates the need for awareness programmes and further researc

Occurrence of aflatoxins and aflatoxin-producing Aspergillus spp. associated with groundnut production in subsistence farming systems in South Africa

Abstract: Author: Ncube, E. Flett, B.C. Waalwijk, C. Viljoen, A. Vol 27 Issue 2 Publication: 2010 Page: 195-198 : Aflatoxins are carcinogenic mycotoxins produced by Aspergillus spp. in groundnut kernels. Forty-six groundnut samples were collected from subsistence farmers in three provinces of South Africa, namely KwaZulu-Natal (KZN), Mpumalanga (MP) and Limpopo (LP), in 2006 and 2007. Aflatoxin levels of groundnut kernels were quantified using an ELISA technique. The occurrence of A. parasiticus colonies was predominant and it was isolated at twice the frequency of A. flavus. Aflatoxins were present in groundnut produced in the northern parts of KZN, where aflatoxin levels of up to 131 parts per billion (ppb) were found. In Mpumalanga and Limpopo, the highest aflatoxin levels were 160 ppb and 2 ppb, respectively. In the Makhanisi and Mbazwane localities situated in KwaZulu-Natal, and in Boshoffontein in Mpumalanga, aflatoxin levels were higher than the maximum permitted level set by the Food and Drug Administration in the USA (20 ppb), the European Union (6 ppb) and the Department of Health in South Africa (10 ppb) for groundnut that is intended for direct human consumption. This study indicates the need for mycotoxin awareness campaigns and control programs to be implemented in rural areas of South Africa

Aflatoxin and fumonisin on sorghum grain from commercial production areas of South Africa

Sorghum plays an important role in food security in Africa where it serves as the staple food for millions of people. The crop, however, is susceptible to infection by mycotoxigenic fungi such as Aspergillus flavus, A. parasiticus, Fusarium andiyazi, F. thapsinum, F. verticillioides and F. proliferatum. This can lead to a reduction in yield and the production of aflatoxin and fumonisin that are harmful to humans and animals. Sorghum grain samples were collected from five cultivars planted at 21 localities in South Africa from 2007-2009. Each sample was subjected to quantitative (q) real-time-PCR to determine the presence and biomass of aflatoxin-producing Aspergillus spp. and fumonisin-producing Fusarium spp. Aflatoxin and fumonisin amounts were also quantified by means of High Performance Liquid Chromatography (HPLC). HPLC results yielded minute amounts of aflatoxin with little or no fungal contamination determined with qPCR. The soft grain genotype NS5511 was more prone to aflatoxin contamination than the other cultivars. Fumonisin-producing Fusarium spp. were absent from sorghum samples collected in 2007. In 2008, sorghum samples from the Northwest and Kwa-Zulu Natal Provinces had small amounts of fungal contamination. In 2009, a low amount of fungi from samples from Northwest, Kwa-Zulu Natal and the Free State Provinces were recorded. Although small amounts of fungi were present, fumonisin were not produced. HPLC and qPCR results indicate that Aspergillus and Fusarium spp. and their mycotoxins do not pose a threat to sorghum production in South Africa

Sampling variation in the quantification of fumonisins in maize samples

Fumonisins produced by F. verticillioides and F. proliferatum cause mycotoxicoses in horses, swine and rats and have been associated with oesophageal cancer in humans. Accurate measurement of mycotoxins is essential for determining the safety of grain and their products for consumption. Four sources of variation were studied, namely sub-sample size, variation within a single maize sub-sample, number of replicates and toxin detection techniques used by independent laboratories. Variation in detected fumonisin levels within a single maize sample was high using the 25 g sub-samples proposed in the Neogen Veratox protocols. A 250 g subsample significantly reduced variation in fumonisin levels of samples. An incremental increase in sample size also improved the number of positive samples recorded. Increasing the number of replicates using the recommended sub-sample size (25 g) did notreduce variation except when the sample had high fumonisin levels. Improved accuracy was recorded when a 250 g sub-sample was used in conjunction with increased replicates. Data from laboratory analyses indicated that ELISA reactions (Agricultural Research Council - Grain Crops Institute) correlated significantly with HPLC results of the Medical Research Council (MRC), but neither of these correlated with results from an independent laboratory. Concentrations determined using ELISA were consistently higher than those from the HPLC (MRC) technique. Quantification technique, sample size, replicate number and laboratory where analyses are conducted, appear to be important sources of variation for quantification of fumonisins