Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
23 November 2021 | Story Leonie Bolleurs | Photo Supplied
With her talk on ‘Breaking the walls of darkness’, Emmie Chiyindiko came in second out of the 74 pitches presented at the recent Falling Walls Science Summit.

“I need you to take a moment and imagine trying to do everything that you do every day … without reliable energy. Or I’ll ask you this … How far would you walk to charge your phone if you didn’t have electricity? Would you walk for hours? Kilometres?”

“Well, that’s what millions of people in sub-Saharan Africa do daily to charge their phones. One billion people globally don’t have access to electricity in their homes and in sub-Saharan Africa, more than half of the population remains in the dark.”

This was the introduction to Emmie Chiyindiko’s talk at the recent Falling Walls Science Summit earlier this month. Emmie, who is a PhD student in Chemistry at the University of the Free State (UFS), came in second out of the 74 pitches presented with her talk on ‘Breaking the walls of darkness’ in the ‘Breakthrough of the year in the emerging talents category’.

Falling Walls Lab is a world-class pitching competition, networking forum, and steppingstone that brings together a diverse and interdisciplinary pool of students, researchers, and early-career professionals by providing a stage for breakthrough ideas, both globally and locally. 

Emmie, who sees getting out of bed every morning as just another opportunity to “be the exceptional young black female scientist that I am”, won the local Falling Walls Lab in Cape Town in October, which resulted in her going through to the finals in Berlin. She plans to host the Falling Walls Lab in Zimbabwe, her homeland, next year. 

This innovator and science communicator, whose work has been covered in Forbes Science, News24, and the Sunday Times, among others, refers to her obtaining second place on the international stage for her research as “a tremendous achievement and a new height in my science communication career. That level of recognition from the world leaders in science, technology, and science engagement cannot be overstated”.

Ending energy poverty

She believes Sustainable Development Goal 7 – leaving no one behind and eradicating global poverty – must be preceded by intentional efforts to end energy poverty. “My research on dye-sensitised solar cells (DSSC) with special metal complexes is among the most interesting alternatives to conventional solar cells.”

Emmie explains: “The design of the cells is inspired by photosynthesis – that good old process plants use to transform sunlight into energy via chlorophyll. Instead of a leaf, the cells start with a porous, transparent film of eco-friendly titanium dioxide nanoparticles. The film is also coated with a range of different dyes that absorb scattered sunlight and fluorescent light. When sunlight hits, it excites the electrons in the dye, creating an endless supply of energy. 

The bright side of this research is that there are several benefits to this invention. It produces energy that is cheap, reliable, and relatively simple and inexpensive to produce. Emmie adds: “These next-generation cells also work impeccably in low-light and non-direct sunlight conditions, providing all-year-round energy with no disruptions. DSSC is also three times cheaper than conventional cells and produces 40% more energy.”

Improving livelihoods 

She continues: “It does not degrade in sunlight over time as do other thin-film cells, making the cells last longer, and requiring less frequent replacement. DSSCs are also mechanically strong, because they are made of lightweight materials and do not require special protection from rain or abrasive objects.”

Emmie has proven that solutions to our current energy situation are available. “We are on the cusp of an energy revolution, and we must act now. Solutions are available, and if we do not seize them during a time of crisis, when will we?”

She believes that creating technology like this can end the energy crisis and improve livelihoods. “Billions of people simply lack enough energy to build a better life. Affordable, abundant, and reliable energy can go a long way to store food, power life-saving medical equipment, and run trains and factories. It can help communities to grow and prosper and to access opportunity and dignity. Societies where people have access to energy have lower childhood mortality, a higher life expectancy, they eat better and drink cleaner water, and have a better literacy rate.”

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