Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
04 April 2019 | Story Leonie Bolleurs | Photo JohanRoux
Prof Chapagain  Inaugural
Prof Ashok Chapagain, Senior Professor in the Department of Agricultural Economics, recently delivered his inaugural lecture on the university’s Bloemfontein Campus. The title of his lecture was Counting Water: Simple yet Complex. From the left are: Dr Engela van Staden, Vice-Rector: Academic; Prof Ashok, Dr Frikkie Maré, Head of the Department of Agricultural Economics; and Prof Danie Vermeulen, Dean of the Faculty of Natural and Agricultural Sciences.

Virtually every economic sector, from agriculture, power generation, manufacturing, beverage, and apparel to tourism, relies on fresh water to sustain its business. Yet, water scarcity and water-pollution levels in river basins around the world are increasing due to growing populations, changing consumption patterns, and poor water governance.

These are the words of Prof Ashok Chapagain, Senior Professor in the Department of Agricultural Economics at the University of the Free State (UFS), who recently delivered his inaugural lecture on the university’s Bloemfontein Campus. The title of his lecture was Counting Water: Simple yet Complex.

He believes that in a world of increasing interconnectedness, equitable and sustainable resource management has become not only a local phenomenon, but also a global one. “The critical factors in managing these resources lie at both ends of the production and consumption chains. The interlinkages between agriculture, trade, economic, and energy policy and water-resources management must be understood,” he said.

Water footprint from farm to cup

The water footprint of a product is the volume of fresh water used to produce the product, measured over the various steps of the production chain. Water use is measured in terms of water volumes consumed or polluted, e.g. a cup of black coffee would take 140 litres of water as a result of water used in various processes, from the farm to the cup! 

Prof Chapagain said: “With the emergence of the water footprint concept, the public could for the first time see that the issue is not only related to direct water use in their houses, but also to their consumption of goods and services, such as food, fibre, and electricity. For example, a developed nation would typically state their water consumption data as around 100-200 litres per capita per day. This information is misleading, as it does not capture the massive amount of water needed to produce food, goods, and services consumed by the nation, which makes the daily water consumption a whopping 3 000-8 000 litres in these developed nations. Consumers, governments, and businesses are beginning to understand how their interests could be sustained in the long run, using this new approach to water-resource management.”

He also spoke about water as an economic enabler. According to him, harnessing the full benefit of water is constrained by three limits: hydrological limits, limits in production efficiency, limits and risks in externalising water footprints. He further elaborated, “Each river basin is unique with respect to amount of rainfall and pattern, rainfall-runoff relation, total available runoff, environmental flow requirements, groundwater recharge, etc. The actual available quantity of water is determined by all these parameters. Hence, there is a hydrological limit to water use in a river basin/aquifers”. He said: “On the other hand, making a process more efficient comes at a price, marking a limit on local efficiency gains. Similarly, importing virtual water to relieve pressure on local water resources would require second-order resources such as foreign currency, and a political will to move from a ‘water and food self-sufficiency’ policy towards a ‘water and food security’ policy. Enhancing the global water-use efficiency by means of trade has socio-economic limitations.” His current research focuses on unravelling these limits to growth, and on developing a generic analytical framework to find optimal solutions to growth under these water limits.

Trade can relieve the strain

Regarding the latter, he said trade in water-intensive goods and services could help relieve the strain on local/national water resources. For example, Switzerland covers merely 18% of its water demand from its internal water resources, i.e. 82% of it is external! South Africa’s external water footprint is only 22% of the total water footprint of national consumption. Hence, the scope of international trade to help alleviate local scarcity is limited by the availability of second-order resources such as foreign exchange, institutional capacity, socio-political context, etc. 

However, globalisation of fresh water brings both risks and opportunities. “Although national water resources could be saved for best alternative uses, the risks of a growing external dependency and the associated risks related to events elsewhere, are often not visible. These water-intensive production processes are vulnerable to the availability of water at the various locations where the production processes take place. The vulnerabilities may result from a range of factors – from reduced river flows, lowered lake levels, and declined ground-water tables to increased salt intrusion in coastal areas, pollution of freshwater bodies, droughts, and a changing climate,” he said.

Water footprint assessment

Prof Chapagain also touched on the Water Footprint Assessment; he believes it has provided a sound method to analyse the water footprint in the relevant context and formulate appropriate response strategies. “The water-footprint assessment breaks down the different water-footprint components and checks the sustainability of these components against three sets of criteria: environmental, economic, and social. The application of the Water Footprint Assessment has evolved from basic quantitative studies to a powerful advocacy tool that can support decision-making and policy processes and help mitigate water-related business risk.

“Counting water drops is simple, yet unravelling the underlying complexities is the key! I count on you to start by counting water drops in counting for sustainable growth,” he concluded.

News Archive

Research eradicates bacteria from avocado facility
2017-01-17

 Description: Listeria monocytogenes Tags: Listeria monocytogenes

Listeria monocytogenes as seen under an electron
microscope. The photo was taken with a transmission
electron microscope at the microscopy unit of the UFS.
Bacteriophages (lollipop-like structures) can be seen
next to the bacterial cells.
Photo: Supplied

“The aim of my project was to identify and characterise the contamination problem in an avocado-processing facility and then to find a solution,” said Dr Amy Strydom, postdoctoral fellow in the Department of Microbial Biochemical and Food Biotechnology at the University of the Free State (UFS).

Her PhD, “Control of Listeria monocytogenes in an Avocado-processing Facility”, aimed to identify and characterise the contamination problem in a facility where avocados were processed into guacamole. Dr Strydom completed her MSc in food science in 2009 at Stellenbosch University and this was the catalyst for her starting her PhD in microbiology in 2012 at the UFS. The research was conducted over a period of four years and she graduated in 2016. The research project was funded by the National Research Foundation.

The opportunity to work closely with the food industry further motivated Dr Strydom to conduct her research. The research has made a significant contribution to a food producer (avocado facility) that will sell products that are not contaminated with any pathogens. The public will then buy food that is safe for human consumption.


What is Listeria monocytogenes?

Listeria monocytogenes is a food-borne pathogenic bacterium. When a food product is contaminated with L. monocytogenes, it will not be altered in ways that are obvious to the consumer, such as taste and smell. When ingested, however, it can cause a wide range of illnesses in people with impaired immune systems. “Risk groups include newborn babies, the elderly, and people suffering from diseases that weaken their immune systems,” Dr Strydom said. The processing adjustments based on her findings resulted in decreased numbers of Listeria in the facility.

The bacteria can also survive and grow at refrigeration temperatures, making them dangerous food pathogens, organisms which can cause illnesses [in humans]. Dr Strydom worked closely with the facility and developed an in-house monitoring system by means of which the facility could test their products and the processing environment. She also evaluated bacteriophages as a biological control agent in the processing facility. Bacteriophages are viruses that can only infect specific strains of bacteria. Despite bacteriophage products specifically intended for the use of controlling L. monocytogenes being commercially available in the food industry, Dr Strydom found that only 26% of the L. monocytogenes population in the facility was destroyed by the ListexP100TM product. “I concluded that the genetic diversity of the bacteria in the facility was too high and that the bacteriophages could not be used as a control measure. However, there is much we do not understand about bacteriophages, and with a few adjustments, we might be able to use them in the food industry.”

Microbiological and molecular characterisation of L. monocytogenes

The bacteria were isolated and purified using basic microbiological culturing. Characterisation was done based on specific genes present in the bacterial genome. “I amplified these genes with polymerase chain reaction (PCR), using various primers targeting these specific genes,” Dr Strydom said. Some amplification results were analysed with a subsequent restriction digestion where the genes were cut in specific areas with enzymes to create fragments. The lengths of these fragments can be used to differentiate between strains. “I also compared the whole genomes of some of the bacterial strains.” The bacteriophages were then isolated from waste water samples at the facility using the isolated bacterial strains. “However, I was not able to isolate a bacteriophage that could infect the bacteria in the facility.

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept