The Swartkops and Missionvale salinas in Port Elizabeth on the east coast of South Africa are surrounding by large informal settlements. The runoff from these settlements contributes largely to the eutrophication of the solar saltworks which in turn has an effect on the biotic functioning of the systems, ultimately affecting the quantity and quality of the salt produced. Inorganic nutrients and organic composition, as well as important biological groups were examined within the brine with the aim of comparing the current condition of the same salinas to their condition twelve years ago. Comparisons between inorganic nutrient concentrations and biological groups showed significantly higher inorganic nutrients, with chlorophyll a concentrations in the Swartkops salina in 2011 being significantly higher than in 2012 and the 1999 and 2011 chlorophyll a concentrations being significantly higher than 2012 in the Missionvale salina. Microalgae found in the salinas were cultured in four different growth media. Cells were stained with Nile Red fluorescent dye in order to estimate the extent of lipids production. Five of the most promising lipid producing species were isolated into a monoculture and grown at different salinities to establish the growth and lipid production in response to salinity. Halamphora coffeaeformis and Navicula sp. were found to be the best candidate species. They grew best at salinities between 50 and 70 psu and produced lipid vesicles consuming approximately 10 percent of the cell.

This study concerns a determination as to whether anaerobic organisms are involved in pulmonary diseases, particularly those of the chronic type.

The structures of the exopolysaccharides from a number of strafos of the bacterial genus KlebsieUa have been investigated and compared. ·All of these polysaccharides have been shown to be composed of regularly repeated oligosaccharide units containing -glucuronic acid and three to five hexose residues, with pyruvic acid ketal and 0-acetyl groups also present in some of the polysaccharides. Graded acid hydrolysis, monitored by gel-permeation chromato graphy, has been used to study the degradation of each polysaccharide to the structurally significant oligosaccharides and fragments of higher molecular weight which are clearly aggregates of these units. In all cases both acidic and neutral oligosaccharides have been isolated in a high degree of purity, which has permitted their characterisation by standard techniques, including partial acid hydrolysis and methylation analysis, and the use of proton magnetic resonance spectroscopy and measurement of optical rotatory power to determine the nature of anomeric linkages. The polysaccharides from Klebsiella K4 and X.pnev.moniae ( oxytoca variant) have been shovm to have linear tetra- and pentasaccharide repeating units respectively, while the structures of those from serotypes K27 and K64 have been found to be more complex, consisting of branched hexasaccharide repeating units with pyruvic acid ketallinked to one sugar residue. In addition, the fungal polysaccharides from two strains of c1yptococcus neoformans have been investigated and shovm to be chemically equivalent. The evidence obtained from partial acid hydrolysis, methylation analysis and Smith-degradation studies performed on one of these polysaccharides is consistent with a structure in which a linear (l-+3)- linked chain of -mannose residues is substituted at position C-2 by either g-glucuronic acid or ll_-xylose. This represents one of the few complete characterisations of a Cryptococcus polysaccharide to be achieved up to the present.

Thesis (M. Phil.)--University of Hong Kong, 1979.

Thesis (M.Sc.-Res.)--University of Wollongong, 2007. / Typescript. Includes bibliographical references: leaf 96-109.

Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references (leaves 206-229).

Plants require ten elements in appreciable quantity and several others in smaller amount for their continued and normal growth. Three of these necessary elements, nitrogen, phosphorus, and potassium are most important because they occur in the soil in quantities which are usually small in proportion to that needed by the plants. Of these three, nitrogen is in most cases the limiting factor because of the ease with which in may be leached from the soil and comparatively large amount assimilated by plants. These factors coupled with the inhibiting high cost of artificially replacing it in the form of commercial fertilizers, make its conservation and efficient utilization of the utmost importance.

Published Article / The LPS, endotoxin of Gram-negative organisms in communal growth as compared to pure culture was the focus of this research. The experiment aimed to show pure and communal samples grown in the presence of the extrinsic stresses. The change in toxicity was measured using the Limulus Amoebocyte Lysate (LAL) test. The overall sensitivity of organisms was similar for the same sanitiser and the same detergent. Growth in community was found not to be the arithmetic sum of the individual growth patterns. The detergents had a marked effect on the growth of all samples throughout the growth cycle. This finding reveals that the acceptable refrigeration temperatures still allows for pathogen growth and thus for biofilm formation. The quantification by LAL showed that the enumeration of the food-borne pathogens isolated from households might not be indicative of acclimatisation obtained over short periods of time and the causal stress could turn these organisms into more or less toxic pathogens.

No description available.

No description available.