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18 April 2019 | Story Rulanzen Martin

The Institute for Reconciliation and Social Justice IRSJ) has initiated a Social Justice Week at the University of the Free State (UFS), which started on Friday 12 April  until Wednesday 17 April 2019. 

Ten key events took place during the week. It ranged from dialogues, workshops, talk shows, debates, and interactive displays and events on issues of multilingualism and diversity, social innovation, engaged scholarship, the Fourth Industrial Revolution, gender sensitisation, sexual consent, sexual preparedness, universal access, disability, anti-discrimination, and security.

There was also a round-table discussion on 17 April 2019 with various UFS stakeholders on off-campus student security as well as an inter-institutional discussion on the same topic. The UFS Debating Society will take on the topic of the UFS Language Policy, while Olga Barends from the Free State Centre for Human Rights will host a dialogue on sexual consent.

The IRSJ has also designed and implemented SOJO-VATION: Social Innovation/ Social Change, which strives to create a foundational platform where ideas of social justice, innovation, and engaged scholarship at the UFS and in society can be hosted. SOJO-VATION partners with the Office for Student Leadership, Development, and Community Engagement.

The collaborating partners for the Social Justice Week includes various UFS stakeholders such as the Sasol library, the Gender and Sexual Equity Office, UFS Protection Services, the Free State Centre for Human Rights, the Student Representative Council (SRC), the Office for Student Leadership Development, Kovsie Innovation, GALA, the FFree State Centre for Human Rights, SRC Associations, the Office for Student Governance, Kovsie Innovate, Start-Up-Grind, EVC, EBL, Community Engagement, the Institutional Transformation Plan (ITP) Dialogues Office, Residence Dialogues, UFS Debating Society, Debate Afrika!, the Center for Universal Access and Disability Support (CUADS), and the Gateway Office. 

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.

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