Chemist of the Month - September 2021
Associate Professor Paul Prenzler
Paul Prenzler is the Chemist of the Month for September 2021, and the first from Regional NSW. He is an academic in the School of Agricultural and Wine Sciences at Charles Sturt University, Wagga Wagga Campus, with a long history of involvement in the RACI Riverina-Murray Section as its past Chair. After going through several postdoctoral positions, each in a different area of research, he is now well-established in the studies involving the olive plant, as well as antioxidants and Indigenous foodstuffs. The latter in particular opened up opportunities to support science education towards local Indigenous communities, which extends his passion and commitment towards providing quality education to students wishing to have the best possible start to a career in chemistry.
Interview conducted by William Li.
WL: Pleasure to interview you tonight, Paul. Firstly, how long have you been an RACI Member?
PP: I became a Member when I was a PhD student, so around 1988.
WL: That’s over 30 years in RACI. You’ve certainly shown quite a bit of loyalty and have found time to be involved in one of the NSW Sections.
PP: That’s right. The one relevant to my area is the Riverina-Murray Section. That’s quite a large area; I did a calculation once and the Section covers around 40,000 km2. From Wagga Wagga out to Griffith is about 200 km, and from Cootamundra (north of Wagga) to Albury is also ~200 km, so the members are quite dispersed. I took over the Chair role around 2000, and I only recently stepped down from that role around 2018. My main involvement in promoting chemistry has been the HSC Chemistry Days that Charles Sturt runs and we get up towards 200 students each year from around 15 high schools. For some schools, it’s a 4-hour bus ride. It’s very popular and both the teachers and students appreciate being given learning opportunities relevant to the curriculum that aren’t available back at school. We’re pleased to share resources such as our labs.
WL: Certainly quite fulfilling to give the kids an idea of what it’s like to study chemistry and a feel of what they could do as a chemist, and giving the motivation as well to take up chemistry in their university studies. Speaking of motivation, what interested you in science?
PP: Quite a few things, actually. When I was small, I used to watch Professor Julius Sumner Miller on television. He had a science show and had a ‘mad scientist’ appearance. I think that inspired me to be a scientist, along with my enjoyment of learning new things. But I had a really good chemistry teacher back in high school and during my first year of studies at university. After studying chemistry, maths and physics, I found the chemistry subjects were much more appealing to me. I found that I naturally liked chemistry so I specialised in chemistry. One of those things that also played into my thinking for chemistry was at a careers night, when I spoke to someone who told me about an industrial chemist who went overseas as part of their job, and it sounded pretty good being paid while working in another country. I did end up doing that with a year of postdoctoral studies in Japan, and had a sabbatical leave in Italy. That advice came true in my life and was somewhat amazing!
WL: Seems pretty common these days for aspiring postdocs to do a stint overseas.
PP: Yes, that was definitely the advice I got during my PhD, when my supervisor told me that I needed to go overseas and work for a while if I was to pursue an academic career. That’s what I did in Japan, and had a few more postdocs before securing a position at Charles Sturt.
WL: Seems like a nice, linear pathway.
PP: Actually not! Every time I changed location, I changed the emphasis of the research I did at the time. Not very good in the short term, but in the long term, it gave me a real breadth of experience. After the Japan stint with Hitachi, I went to ANU studying platinum chemistry and electrochemistry. Then at University of Melbourne, my studies were more focused on polyoxometalates. And finally at Charles Sturt, the focus is on analytical chemistry. So we’re geared towards working on issues relating to regional and rural Australia. One of the first projects I got involved in was looking at phenolics in olives, which is important for olive oil quality, but also linked with the health benefits of olive oil, as well as sensory properties. So I changed direction quite a bit to fit in with what the university was more likely to support. The other project I got involved with was on wine chemistry, particularly a phenomenon called ‘random browning’, which was linked to the use of ascorbic acid as a preservative in white wine. It wasn’t actually that random; it was linked to the amount of oxygen, sulfur dioxide and ascorbic acid present in the wine at bottling, and a lack of these substances when certain reactions that take place resulting in the formation of pigments.
WL: Hmmm. So when it comes to olive oil at the local supermarket, I’ll think about the phenolics in it.
PP: That’s right. Phenolics are very important to oil quality, especially extra-virgin olive oil. We also did work on olive leaf extract, and we were the first group in the world to show that oleuropein in the extract is bioavailable; it gets absorbed by the body. There was controversy as to whether phenolic compounds were actually absorbed or just passed through the digestive system. We established that ingestion of olive leaf extract will give off a signal in urine that can be detected, which showed that the compound did get absorbed and excreted.
WL: Quite interesting the amount of research you can get from the humble olive. So how are you finding your current career so far?
PP: Most of the olive research in Australia is now done elsewhere, so we’ve looked in other areas. We’ve also done work on antioxidant activity – one of my main research areas at the moment. We’ve also worked with the local Wiradjuri people to investigate the properties of their medicinal plants - I’ve got a PhD student working on that now. So it started with olives, then looking at the antioxidant properties around that, and now looking into Indigenous medicinal plants.
WL: Pretty fascinating in the range of Indigenous foodstuffs around, and how unique it is when it comes to cuisine and how it can enhance the cuisines we know. Very surprising how good it can be.
PP: It’s a growing area, but one thing we’re conscious of in our research is working with communities by ensuring whatever benefits arise from the research are passed on to the communities. Dr Joanne Jamie is a leader in this area, and one such initiative is the National Indigenous Science Education Program (NISEP), of which I’m the Director of the Charles Sturt ‘hub’. We work with 3 local high schools, running science shows and giving the Indigenous students the opportunity to attend a larger one at Redfern for National Science Week. It’s a tremendous opportunity for the students to meet up with other Indigenous kids to share their love of science.
WL: Lovely, giving these wonderful opportunities to them. However, had COVID-19 impacted on these initiatives?
PP: For NISEP, yes. We did work a way around that and used a mixture of Zoom and our student leaders within the schools to have science shows held last year. Despite COVID, the feedback was really good to do it again and the student leaders got a lot out of it. We’re looking forward to running it in the usual manner this year. Fortunately, at Wagga Wagga, we got next to no cases of COVID-19.
WL: You’ve certainly contributed much to RACI, had quite a varied career path, working on olives, antioxidants and Indigenous foodstuffs. Now if there’s one piece of advice you want to give to people, what would it be?
PP: I’d say if you enjoy chemistry, there’s a whole range of careers out there, go where your interests lie and be prepared to look for opportunities. I never thought I would’ve done a postdoc in Japan, but an opportunity came up, I applied for it and got a year in Japan out of it. Just an amazing experience; life-wise, I wouldn’t swap it. Also, here at Charles Sturt, there is a compulsory subject called Industrial Experience, consisting of 180 hours of laboratory experience. Students learn what it’s like to work as a chemist in a laboratory, and they get excited about those opportunities in laboratory work, which is quite a valuable head start in their careers. Even before this subject was established 10-12 years ago, our students have close to 100% success rate in finding a job, because so much of what we do is hands-on. Our third-year students have to develop their own method involving some high-end equipment such as HPLC-MS with a quadrapole time-of-flight mass spectrometer, which is quite top-end, but we let them loose on it to get this invaluable experience!
WL: That’s excellent, being able to gain as much practical experience; even better if it also involves instrument troubleshooting, or doing tasks that even experienced instrument operators have difficulty with, such as changing a column or validating a method. Never got a chance during my studies to get my hands on these sort of instruments - always a demonstrator who ran the instruments to process and analyse the samples. One final question, what do you like to do in your spare time, if you have any?
PP: Spare time is fishing, gardening, watching movies with my wife and spending time with my family. If I’m lucky, I get to spend an afternoon a month going fishing. I’m also involved in one of the local churches in Wagga Wagga.