https://commons.ru.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://commons.ru.ac.za/vital/access/manager/Repository/vital:2679 Wed 12 Oct 2022 10:08:59 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3162 Wed 12 May 2021 23:45:34 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2209 Wed 12 May 2021 23:25:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1535 Wed 12 May 2021 22:59:17 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11009 Wed 12 May 2021 22:32:57 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3180 Wed 12 May 2021 22:17:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1518 Wed 12 May 2021 20:31:31 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11075 Wed 12 May 2021 20:24:37 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5081 Wed 12 May 2021 20:19:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5255 Wed 12 May 2021 19:51:15 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4011 98 % in 24 – 30 h batch cycles. Comparable performance between the packing materials was shown. Uptake by the packing was negligible and stripping of compounds induced by aeration had a minimal effect on biodegradation efficiency. Reactor performances are discussed in relation to sequencing batch operation and nutrient requirements necessary to sustain fungal activity in inert vs. organic material packed systems. It was shown that a co-culture consisting of sulphate-reducing and dechlororespiring bacteria established in fed-batch and soil flasks, as well as pine chip-packed fluidized bed reactors. Results showed reductive dechlorination of 2,4,6-TCP to be in strict dependence on the activity of the sulphate-reducing population, sulphate and lactate concentrations. Transformation to 2,4-DCP, 4-CP and phenol was enhanced in sulphate deficient conditions. Dechlororespiring activity was found to be dependent on the fermentative activity of sulphate-reducing bacteria, and the culture was also shown to mobilize and dechlorinate TCP in soils contaminated with the pollutant. Linking the systems achieved degradation of the compound by > 99 % through fungal mineralization of metabolites produced in the dechlororespiring stage of the system. pH correction to the anaerobic reactor was found to be necessary since acidic effluent from the fungal reactor inhibited sulphate reduction and dechlorination. The fungal reactor system was evaluated at intermediate-scale using a complex waste oil recycling effluent. Substantial COD reduction (> 96 % in 48 h batch cycles) and removal of specific effluent hydrocarbon components was shown in diluted, undiluted (COD > 37 g.L⁻¹) and 2,4,6-TCP-spiked effluents. Industrial application of the fungal reactor was evaluated in a 14 m³ pilot plant operated on-site at a waste oil processing plant.]]> Wed 12 May 2021 19:45:11 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11095 Wed 12 May 2021 19:15:19 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2863 Wed 12 May 2021 19:01:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11081 Wed 12 May 2021 18:39:08 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4132 50%). In the current study, the specific activities of a range of extracellular hydrolytic enzymes (L-alanine aminopeptidase, L-leucine aminopeptidase, arylsulphatase, α-glucosidase, β- glucosidase, protease and lipase) were monitored in a sulfide gradient within a biosulphidogenic RSBR. Data obtained indicated that the specific enzymatic activities increased with the depth of the RSBR and also correlated with a number of the physicochemical parameters including sulfide, alkalinity and sulfate. The activities of α- glucosidase and β-glucosidase were higher than that of the other enzymes studied. Lipase activity was relatively low and studies conducted on the enzyme-enzyme interaction using specific enzyme inhibitors indicated that lipases were probably being digested by the proteases. Further studies to determine the impact of sulfide on the enzymes, showed an increase in the enzyme activity with increasing sulfide concentration. Possible direct affects were investigated by looking for changes in the Michaelis constant (Km) and the maximal velocity (Vmax) of the crude enzymes with varying sulfide concentrations (250, 400 and 500 mg/l) using natural and synthetic substrates. The results showed no significant difference in both the Km and the Vmax for any of the hydrolytic enzymes except for the protease. The latter showed a statistically significant increase in the Km with increasing sulfide concentration. Although this indicated a direct interaction, this difference was not large enough to be of biochemical significance and was consequently not solely responsible for the enhanced hydrolysis observed in the RSBR. Investigation into the floc characteristics indicated that the biosulphidogenic RSBR flocs were generally small in size and became more dendritic with the depth of the RSBR. Based on the above data, the previously proposed descriptive models of enhanced hydrolysis of particulate organic matter in a biosulphidogenic RSBR has been revised. It is thought that the effect of sulfide on the hydrolysis step is primarily indirect and that the reduction in floc size and alteration of the floc shape to a more dendritic form is central to the success of the process.]]> Wed 12 May 2021 18:32:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10869 Wed 12 May 2021 18:27:33 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3943 Wed 12 May 2021 18:23:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4833 Wed 12 May 2021 16:27:19 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1884 Wed 12 May 2021 16:10:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11015 Wed 12 May 2021 15:53:26 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10780 Wed 12 May 2021 15:51:16 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3935 Wed 12 May 2021 15:49:47 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3672 Tue 31 Aug 2021 09:50:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5317 Thu 13 May 2021 08:56:52 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5917 Thu 13 May 2021 08:10:07 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5796 Thu 13 May 2021 06:35:55 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10979 Thu 13 May 2021 06:15:42 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5813 Thu 13 May 2021 06:10:59 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:952 Thu 13 May 2021 06:01:16 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11014 Thu 13 May 2021 05:38:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11085 Thu 13 May 2021 04:09:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:752 Thu 13 May 2021 03:51:06 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11093 Thu 13 May 2021 03:35:04 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:10981 Thu 13 May 2021 03:10:28 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1317 Thu 13 May 2021 02:50:56 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:8499 Thu 13 May 2021 02:31:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3350 Thu 13 May 2021 02:10:52 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3351 Thu 13 May 2021 01:50:00 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5330 Thu 13 May 2021 01:25:24 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3937 Thu 13 May 2021 01:19:45 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5826 Thu 13 May 2021 01:10:24 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:11088 Thu 13 May 2021 00:28:23 SAST ]]>