Browsing by Author "Bester, M."

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    FLO gene-dependent phenotypes in industrial wine yeast strains
    (2010) Govender, P.; Bester, M.; Bauer, Florian
    Most commercial yeast strains are nonflocculent. However, controlled flocculation phenotypes could provide significant benefits to many fermentation-based industries. In nonflocculent laboratory strains, it has been demonstratedthat it is possible to adjust flocculation and adhesion phenotypes to desired specifications by altering expression of the otherwise silent but dominant flocculation (FLO) genes. However, FLO genes are characterized by high allele heterogeneity and are subjected to epigenetic regulation. Extrapolation of data obtained in laboratory strains to industrial strains may therefore not always be applicable. Here, we assess the adhesion phenotypes that are associated with the expression of a chromosomal copy of the FLO1, FLO5, or FLO11 open reading frame in two nonflocculent commercial wine yeast strains, BM45 and VIN13. The chromosomal promoters of these genes were replaced with stationary phase-inducible promoters of the HSP30 and ADH2 genes. Under standard laboratory and wine making conditions, the strategy resulted in expected and stable expression patterns of these genes in both strains. However, the specific impact of the expression of individual FLO genes showed significant differences between the two wine strains and with corresponding phenotypes in laboratory strains. The data suggest that optimization of the flocculation pattern of individual commercial strains will have to be based on a strain-by-strain approach. © 2009 Springer-Verlag.
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    Nutrition related knowledge and practices of hypertensive adults attending hypertensive clinics at day hospitals in the Cape Metropole
    (AOSIS Publishing, 2004-05) Becker, H.; Bester, M.; Reyneke, N.; Labadarios, D.; Monyeki, K. D.; Steyn, N. P.
    The aim of this study was to determine nutrition knowledge and dietary practices of hypertensive adults attending hypertensive clinics at Day Hospitals in the Cape Metropole. Ten Day Hospitals were randomly selected from a total of 31 Day Hospitals and the first participants attending the hypertension clinics per day were recruited. A total of 85 participants were evaluated. The weight, height, waist and hip circumference of each participant was measured, as well as their blood pressure. Knowledge of dietary intake was obtained by completing a questionnaire, during an interview with the patient. Knowledge regarding salt usage indicated that a large percentage (34.1 %) of participants believed that flavour enhancers like Aromat or Fondor could safely be used instead of table salt. Furthermore, 23.5% reported that tinned and smoked meat or fish have a low sodium (salt) content. Fruit and vegetables were perceived as having a positive effect on hypertension by 74.1 % of participants. However, only 15% of the group knew that the recommendation for their usage was five or more servings per day. Only 12.9% of participants in this study had a normal weight (body mass index (BMI) < 25), 25.9% were overweight (BMI 25 - 29.9) and 61.2% were obese (BMI ^30); 84.7% recognized the association between obesity and hypertension. A large waist circumference (> 88 cm in women; 102 cm in men) was found in 61.2% of participants, however, only 18.2% of black men had such a measurement. Uncontrolled blood pressure readings (> 140/90 mm Hg) were found in 61.2% of these patients at the hypertension clinics.