Changes in the Phenolic Composition and Antioxidant Activity of Pinotage, Cabernet Sauvignon, Chardonnay and Chenin blanc Wines During Bottle Ageing

The effect of bottle ageing on the antioxidant activity of Pinotage, Cabernet Sauvignon, Chardonnay and Chenin blanc wines, using the 2,2'-azino-di-(3-ethylbenzothialozine-sulphonic acid) radical cation (ABTS•+) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH0) scavenging assays, was determined. Storage at 0°C, 15°C or 30°C for a period of 12 months resulted in a significant (p ≤ 0.05) decrease in both the total antioxidant activity (TAAAnTs and TAAoPPH) and the total phenol content of the wines. The antioxidant potency of the total phenols of most of the wines, which is a ratio of antioxidant activity to the total phenol content, also decreased. The total anthocyanins in the red wines decreased significantly (p ≤ 0.05) over 12 months except for storage at 0°C, while the flavanol content of the Pinotage, Cabernet Sauvignon and Chardonnay wines increased up to nine months storage with a subsequent decrease to 12 months. The flavonol content of all the wines decreased, while only minor changes in their hydroxycinnamate content were observed during the storage period. Understanding the complexity of these reactions may provide clues for stabilising especially red wines to preserve the antioxidant activity without losing the beneficial effects of colouring and flavour development during bottle ageing

Cancer patterns in four districts of the Transkei region 1991-1995

Background. Oesophageal cancer (OC) is an important public health problem among the Xhosa-speaking people of the Transkei region in the Eastern Cape Province, South Africa, with incidence rates for males among the highest in the world.Objectives. To record the occurrence of cancer among men and women of all ages in four districts in the Transkei during the period 1991 - 1995, to identify common cancers and to compare the variations in cancer incidences in this region with incidences in Africa and the rest of the world.Design. Cancer registration of cases reported from all clinics and hospitals was conducted in the four selected districts.Setting. The districts included Centane (Kentani), Butterworth, Bizana and Lusikisiki in the Transkei region.Methods. Active and passive methods were used to collect data, which were analysed using the Statistical Analyses Systems (SAS) package.Results. The mean annual number of all cancer cases reported was 310, with age-standardised incidence rates (ASIRs, world standard) of 98.2/100 000 and 74.3/100 000 for males and females, respectively. The most frequently reported cancer was OC, with mean annual ASIRs of 76.6/100 000 and 36.5/100 000 for males and females, respectively, with a male/female ratio of 2:1.Conclusion. The present data confirm previous reports that OC rates in Centane have consistently remained very high, whereas time-dependent changes in the incidence of OC have occurred in Butterworth, Bizana and Lusikisiki suggesting changes in the risk determinants in these districts

Leukoencephalomalacia in two horses induced by oral dosing of fumonisin B₁

Leukoencephalomalacia (LEM) was induced by the oral administration of fumonisin B₁ (FB₁) to 2 horses: a filly received 59,5mg/kg of a 50% preparation of FB₁ administered in 21 doses of 1,25-4mg/kg over 33 days; a colt, 44,3mg/kg of 95% pure FB₁ in 20 doses of 1-4 mg/kg in 29 days. Both animals developed nervous signs such as apathy, changes in temperament, inco-ordination, walking into objects, and one showed paralysis of the lips and tongue. Characteristic lesions of LEM were present in the brains. These trials proved conclusively that FB₁ can induce LEM in horses.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Leukoencephalomalacia in a horse induced by fumonisin B₁isolated from Fusarium moniliforme

Each of two horses was dosed by stomach tube with culture material on maize of Fusarium moniliforme MRC 826. One horse developed severe hepatosis and mild oedema of the brain after 6 doses of 2,5 g of culture material/kg body mass/day in 7 days. The second horse, in a similar experiment but at a dosage rate of 1,25 g/kg/day, developed mild hepatosis and moderate oedema of the brain. In both animals the brain oedema was particularly noticeable in the medulla oblongata. The mycotoxin fumonisin B₁was extracted and purified from the culture material of F. moniliforme MRC, 826 which contained approximately 1 g/kg of this compound. A horse was injected intravenously 7 times from Day 0-Day 9 with 0,125 mg of fumonisin B₁/kg body mass/day. Clinical signs of neurotoxicosis, which appeared on Day 8, included nervousness followed by apathy, a wide-based stance, trembling, ataxia, reluctance to move, paresis of the lower lip and tongue, and an inability to eat or drink. Euthanasia was performed on the horse on Day 10 while the animal was in a tetanic convulsion. The principal lesions were severe oedema of the brain and early, bilaterally symmetrical, focal necrosis in the medulla oblongata. This report provides experimental evidence that fumonisin B₁, produced by F. moniliforme, causes equine leukoencephalomalacia.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

Controversies in fumonisin mycotoxicology and risk assessment

Fusarium verticillioides causes several animal diseases and the contamination maize suggests that it could adversely affect human health. The fumonisin B mycotoxins were characterized from the fungal culture material and shown to be the causative principle responsible for the major mycotoxicological effects of the fungus in experimental and farm animals. The main focus was on the toxicological effects in rats and mice, the outcome of which played an important role in setting risk assessment parameters for exposure of the fumonisins to humans. The International Agency for Research on Cancer characterized the fumonisins as Group 2B carcinogens. Several controversial findings regarding the toxicological effects of the culture material of the fungus, the genotoxicity and carcinogenicity of pure fumonisin B1 (FB1) in rats have been reported that should be clarified prior to assessing the risk in humans. The underlying differences between the diets with the high protein levels are likely to sensitize the kidneys to FB1-induced toxic and carcinogenic effects. Several other dietary factors, such as plant extracts (antioxidants) and dietary Fe, could either stimulate or inhibit cancer induction of FB1, which complicates the comparison of toxicological effects in experimental animals. Cognisance should be taken of the modulating role of dietary constituents as it will determine the outcome of toxicological assays and determine the threshold of an adverse effect in a specific target organ to be used in determining risk assessment parameters. © SAGE Publications 2012

Antioxidant activity of South African red and white cultivar wines: Free radical scavenging

The free radical scavenging activity of South African red (n = 46) and white (n = 40) cultivar wines was determined using 2,2′-azinobis(3-ethylbenzothialozinesulfonic acid) radical cations (ABTS·+) and 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH·). The total antioxidant activities (TAA) of red and white wines using ABTS·+ were 14.916 and 0.939 mM Trolox, respectively, at corresponding total phenol (TP) contents of 2339.0 and 273.8 mg of gallic acid equiv/L. Ruby Cabernet wines had the lowest TAAABTS (13.177 mM Trolox) of the red wines, whereas the TAAABTS values of Chardonnay and Chenin blanc wines were the highest (1.060 mM Trolox) and lowest (0.800 mM Trolox) of the white wines. The TAADPPH values were of the same magnitude as the TAAABTS values, and similar trends were observed. TAA correlated (P < 0.001) with total phenol content of red (r = 0.935) and white (r = 0.907) wines, as well as flavanol content of red wines (r = 0.866) and tartaric acid ester content of white wines (r = 0.767). Canonical discriminant analysis using phenolic composition and antioxidant activity was applied to differentiate between red and white cultivar wines.The free radical scavenging activity of South African red (n = 46) and white (n = 40) cultivar wines was determined using 2,2′-azinobis(3-ethylbenzothialozinesulfonic acid) radical cations (ABTS·+) and 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH·). The total antioxidant activities (TAA) of red and white wines using ABTS·+ were 14.916 and 0.939 mM Trolox, respectively, at corresponding total phenol (TP) contents of 2339.0 and 273.8 mg of gallic acid equiv/L. Ruby Cabernet wines had the lowest TAAABTS (13.177 mM Trolox) of the red wines, whereas the TAAABTS values of Chardonnay and Chenin blanc wines were the highest (1.060 mM Trolox) and lowest (0.800 mM Trolox) of the white wines. The TAADPPH values were of the same magnitude as the TAAABTS values, and similar trends were observed. TAA correlated (P < 0.001) with total phenol content of red (r = 0.935) and white (r = 0.907) wines, as well as flavanol content of red wines (r = 0.866) and tartaric acid ester content of white wines (r = 0.767). Canonical discriminant analysis using phenolic composition and antioxidant activity was applied to differentiate between red and white cultivar wines.ArticleArticl

Mycotoxicological research in South Africa 1910-2011

The British mycologist, I.B. Pole-Evans, was appointed as the first South African government mycologist in 1905 following the Anglo-Boer War (1899-1902). The Onderstepoort Veterinary Research Institute was founded in 1908 with the Swiss veterinarian, Arnold Theiler, as the first director. Thus, the stage was set for the commencement of mycotoxicological research when the Union of South Africa came into being in 1910. The first accounts of this pioneering research appeared in the 'Seventh and eight reports of the Director of Veterinary Research, Union of South Africa. 1918' in which D.T. Mitchell reported on the experimental reproduction of the neurotoxic syndrome, diplodiosis, in cattle with pure cultures of Stenocarpella maydis (= Diplodia zea) isolated by P.A. Van der Bijl and grown on sterile maize kernels. This is the first report of the experimental reproduction of a veterinary mycotoxicosis with a pure culture of a fungus in South Africa and possibly in the world. This seminal research was followed by a great deal of multidisciplinary research on veterinary mycotoxicoses as well as human syndromes in which fungal toxins are suspected to be involved, taxonomy of mycotoxigenic fungi and chemistry of mycotoxins in South Africa. The mycotoxicoses studied in South Africa include the following (more or less in chronological order): diplodiosis, Paspalum staggers, aflatoxicosis, human hepatocellular carcinoma, ochratoxicosis, lupinosis, facial eczema, tremorgenic mycotoxicosis, hyperoestrogenism, stachybotryotoxicosis, ergotism, leukoencephalomalacia and human oesophageal cancer. A major breakthrough in mycotoxicological research was made in South Africa in 1988 with the isolation and chemical characterisation of the carcinogenic fumonisins produced by Fusarium verticillioides in maize. Current research at the PROMEC Unit of the South African Medical Research Council on the risk assessment of fumonisins and intervention methods to reduce fumonisin intake by rural populations on a maize staple diet is highlighted. This paper concludes with a selected list of mycotoxicological publications by South African mycologists/plant pathologists, veterinarians and chemists/biochemists. © 2011 Wageningen Academic Publishers