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Emerita Professor Mary Fletcher
Emerita Professor

Mary Fletcher

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Overview

Background

Professor Mary Fletcher is a natural product organic chemist, and led the Natural Toxin group within the Centre for Animal Science, Queensland Alliance for Agricultural and Food Innovation (QAAFI) 2010-2024,before being appointed Emeritus Professor in 2024. She previously worked as a research chemist at both The University Queensland and Queensland Primary Industries (Biosecurity Queensland), before joining the Queensland Alliance for Agricultural and Food Innovation in 2010. Prof Fletcher's current interest focuses on bioactives that reduce enteric methane and the application of slow release delivery systems appropriate to rangeland grazing systems. Prof Fletcher has an industry recognised expertise as an applied organic chemist with a specialist interest in the identification and analysis of natural toxins and other bioactives in a range of plants, fungi and agricultural products. Such toxins and bioactives can affect both human and animal health posing risks to livestock production, food safety and market access.

Prof Fletcher is also an Affiliate Professor in the School of Chemistry and Molecular Biosciences (http://www.scmb.uq.edu.au/index.html), and an Affiliated Scientist at the Biosciences eastern & central Africa-International Livestock Research Institute (BecA-ILRI) Hub in Nairobi, Kenya (http://hub.africabiosciences.org/).

Prof Fletcher is a Fellow of the Royal Australian Chemical Institute and in 2016 was elected President of the Queensland Branch of the Royal Australian Chemical Institute (http://www.raci.org.au/branches/qld-branch).

Availability

Emerita Professor Mary Fletcher is:
Not available for supervision

Qualifications

  • Bachelor of Science, The University of Queensland
  • Bachelor (Honours) of Chemistry, The University of Queensland
  • Doctor of Philosophy, The University of Queensland

Research interests

  • Slow release inserts to deliver bioactive compounds that reduce enteric methane

    Methane emissions from the beef cattle sector accounts for ~7% of Australia’s greenhouse gas emissions. This collaborative UQ-DAF project brings together a team of interdisciplinary scientists and applies novel technologies to progress the industry goal of achieving a carbon neutral beef industry by 2030. The synthetic feed additive 3 nitrooxypropanol (3-NOP) has shown promise in enteric methane mitigation. This compound targets the nickel enzyme methyl-coenzyme M reductase (MCR) in rumen archea, thereby inhibiting the last step of CH4 formation by reversibly oxidizing the nickel cofactor from Ni(I) to Ni(II). Applications to date have necessitated daily dosing regimes relevant mostly for intensive cattle systems, and this project seeks to provide alternate delivery mechanisms to enable application in extensive systems. In extensive grazing systems, most supplements are normally delivered through licks, with little or no control of intake by individual animals. Many methane mitigating active-agents including 3-NOP are required to be delivered consistently to the rumen to be effective. This project seeks to deliver a novel rumen insert for controlled release of active-agents to provide a sustained slow-release dose. Such technology avoids any process issues associated with traditional bolus capsule systems, where the capsule itself presents problems at abattoir. It is envisaged that the novel insert by comparison would be completely biodegraded with no problematic remains at abattoir.

  • Beneficial Sugars in Stingless Bee Honey

    Stingless bees (Meliponini) occur in all tropical and sub-tropical regions, and honey from these native bees has a long history of traditional indigenous use with a range of purported therapeutic properties. Prof Fletcher's research has identified the unusual low GI disaccharide trehalulose as a predominant sugar and distinctive marker of stingless bee honey in five species across three continents Australia, Malaysia and Brazil. The presence of this beneficial sugar has added support to the health claims of these native Meliponini honeys and provided impetus to this emerging industry. This is the first report of this unusual disaccharide as a major component of honey, and indeed the first significant natural occurrence in any food. Prof Fletcher's research team has further demonstrated that this rare sugar is produced by the bees themselves via an enzymatic isomerisation of nectar sucrose - further evidence of the unique characteristics of these stingless bees and the honey they produce.

  • Natural Toxins

    Prof Fletcher's research interests also encompass the identification and analysis of natural toxins and bioactives in a range of plants, fungi and agricultural products. Such toxins have the potential to form residues in agricultural products and pose a risk to both livestock and human consumers. Toxins of particular interest include mycotoxins, pyrrolizidine alkaloids, indospicine and simplexin. Her natural toxin research focusses on minimising the impacts of plant toxins on Australian livestock production. Plant toxins can have wide ranging animal impacts, depending on their chemical structure and have the potential to contribute to ill thrift through specific toxicoses such as Pimelea poisoning and pyrrolizidine alkaloid associated liver disease, and reproductive losses through abortion and teratogenic effects, or calf losses associated with premature births, weak calves, or failure to suckle. Devising strategies to deal with diverse plant toxins is not easy, as the chemical action and target organ varies considerably, and the best line of action is prevention rather than remedial treatment. In pasture systems, it is difficult to prevent consumption of poisonous plants, other than by total removal from the pasture which is generally not possible. However, plant consumption does not necessarily equal uptake of the toxin, and the approach of the proposed research is to devise strategies to enable toxin breakdown within the rumen before absorption into the animals circulatory systems. Our research approach is to capitalise on natural rumen response by isolating microbes capable of degrading toxins (for use as preventative probiotics), and investigating toxin absorbents and/or biopolymers to foster toxin-degrading microbe populations. Initially this research will be applied to the Pimelea toxin, simplexin, which causes frequently fatal poisoning in cattle grazing inland pastures of Australia with productivity losses estimated to be up to $50 million in bad years. Further interests include the presence of pyrrolizidine alkaloids in Australian honey and identification of diverse floral sources of these alkaloids using LCMS technologies to confirm alkaloid profiles. A collaborative project with Queensland Health is also investigating authenticity, adulteration and providence of these honeys using stable isotope MS techniques.

Research impacts

Throughout her career Prof Fletcher has applied her chemical skills to address diverse problems that pose threats to agricultural industries, from the identification of fruit fly pheromones to the determination of plant toxins responsible for livestock deaths, to the identification of bone volatiles attractive to phosphorous deficient cattle and more recently the identification of unusual beneficial sugars in stingless bee honey and the application of slow release devices for the release of bioactives to control enteric methane production in rangeland cattle. Her work has particular application in the areas of food safety and food security, both in Australia and overseas, including projects addressing the impacts of carcinogenic mycotoxin contamination of staple foods in sub-saharan Africa.

Current research funded by Meat and Livestock Australia (MLA) aims to develop a rumen insert that is applicable in extensive production systems to reduce methane emissions from northern Australia beef herds and applies novel biopolmyer technologies to progress the industry goal of achieving a carbon neutral beef industry by 2030. This collaborative UQ-DAF project aims to produce a rumen insert that slowly releases active-agents (such as 3-NOP) into the rumen over an extended period of time. The use of a rumen insert will mean that each animal will receive the treatment and should establish a more consistent reduced methane emission, when compared to other methods.

Works

Search Professor Mary Fletcher’s works on UQ eSpace

281 works between 1983 and 2025

81 - 100 of 281 works

2019

Journal Article

Analysis of Pyrrolizidine alkaloids in Queensland honey: Using low temperature chromatography to resolve stereoisomers and identify botanical sources by UHPLC-MS/MS

Hungerford, Natasha L., Carter, Steve J., Anuj, Shalona R., Tan, Benjamin L. L., Hnatko, Darina, Martin, Christopher L., Sharma, Elipsha, Yin, Mukan, Nguyen, Thao T. P., Melksham, Kevin J. and Fletcher, Mary T. (2019). Analysis of Pyrrolizidine alkaloids in Queensland honey: Using low temperature chromatography to resolve stereoisomers and identify botanical sources by UHPLC-MS/MS. Toxins, 11 (12) 726, 726. doi: 10.3390/toxins11120726

Analysis of Pyrrolizidine alkaloids in Queensland honey: Using low temperature chromatography to resolve stereoisomers and identify botanical sources by UHPLC-MS/MS

2019

Journal Article

Curcumin-based photosensitization inactivates Aspergillus flavus and reduces aflatoxin B1 in maize kernels

Temba, Benigni A., Fletcher, Mary T., Fox, Glen P., Harvey, Jagger, Okoth, Sheila A. and Sultanbawa, Yasmina (2019). Curcumin-based photosensitization inactivates Aspergillus flavus and reduces aflatoxin B1 in maize kernels. Food Microbiology, 82, 82-88. doi: 10.1016/j.fm.2018.12.013

Curcumin-based photosensitization inactivates Aspergillus flavus and reduces aflatoxin B1 in maize kernels

2019

Journal Article

Antioxidant rich extracts of Terminalia ferdinandiana inhibit the growth of foodborne bacteria

Akter, Saleha, Netzel, Michael E., Tinggi, Ujang, Osborne, Simone A., Fletcher, Mary T. and Sultanbawa, Yasmina (2019). Antioxidant rich extracts of Terminalia ferdinandiana inhibit the growth of foodborne bacteria. Foods, 8 (8) 281, 281. doi: 10.3390/foods8080281

Antioxidant rich extracts of Terminalia ferdinandiana inhibit the growth of foodborne bacteria

2019

Journal Article

Antioxidant-rich extracts of Terminalia ferdinandiana interfere with estimation of cell viability

Akter, Saleha, Addepalli, Rama, Netzel, Michael E., Tinggi, Ujang, Fletcher, Mary T., Sultanbawa, Yasmina and Osborne, Simone A. (2019). Antioxidant-rich extracts of Terminalia ferdinandiana interfere with estimation of cell viability. Antioxidants, 8 (6) 191, 191. doi: 10.3390/antiox8060191

Antioxidant-rich extracts of Terminalia ferdinandiana interfere with estimation of cell viability

2019

Journal Article

Pyrrolizidine alkaloids of Blue Heliotrope (Heliotropium amplexicaule) and their presence in Australian honey

Carpinelli de Jesus, Matheus, Hungerford, Natasha L., Carter, Steve J., Anuj, Shalona R., Blanchfield, Joanne T., De Voss, James Joseph and Fletcher, Mary T. (2019). Pyrrolizidine alkaloids of Blue Heliotrope (Heliotropium amplexicaule) and their presence in Australian honey. Journal of Agricultural and Food Chemistry, 67 (28) acs.jafc.9b02136, 7995-8006. doi: 10.1021/acs.jafc.9b02136

Pyrrolizidine alkaloids of Blue Heliotrope (Heliotropium amplexicaule) and their presence in Australian honey

2019

Journal Article

Bioaccumulation and Distribution of Indospicine and Its Foregut Metabolites in Camels Fed Indigofera spicata

Netzel, Gabriele, Tan, Eddie T. T., Yin, Mukan, Giles, Cindy, Yong, Ken W. L., Al Jassim, Rafat and Fletcher, Mary T. (2019). Bioaccumulation and Distribution of Indospicine and Its Foregut Metabolites in Camels Fed Indigofera spicata. Toxins, 11 (3) 169, 169. doi: 10.3390/toxins11030169

Bioaccumulation and Distribution of Indospicine and Its Foregut Metabolites in Camels Fed Indigofera spicata

2019

Journal Article

Assessing the risk of residues of the toxin indospicine in bovine muscle and liver from north-west Australia

Netzel, Gabriele, Palmer, Dieter G., Masters, Anne M., Tai, Samantha Y., Allen, Jeremy G. and Fletcher, Mary T. (2019). Assessing the risk of residues of the toxin indospicine in bovine muscle and liver from north-west Australia. Toxicon, 163, 48-58. doi: 10.1016/j.toxicon.2019.03.007

Assessing the risk of residues of the toxin indospicine in bovine muscle and liver from north-west Australia

2019

Conference Publication

Adsorbents for the sequestration of the Pimelea toxin, simplexin

Gordon, Russell J., Hungerford, Natasha L., Laycock, Bronwyn, Ouwerkerk, Diane and Fletcher, Mary T. (2019). Adsorbents for the sequestration of the Pimelea toxin, simplexin. Northern Beef Research Update Conference (NBRUC) 2019, Brisbane, QLD, Australia, 19 - 22 August 2019.

Adsorbents for the sequestration of the Pimelea toxin, simplexin

2019

Conference Publication

Biopolymer composites for slow release to manage Pimelea poisoning in cattle

Gauthier, Emilie, Ouwerkerk, Diane, Laycock, Bronwyn and Fletcher, Mary (2019). Biopolymer composites for slow release to manage Pimelea poisoning in cattle. The Third International Tropical Agriculture Conference TropAg 2019 , Brisbane, QLD Australia, 11-13 November 2019. Basel, Switzerland: MDPI. doi: 10.3390/proceedings2019036097

Biopolymer composites for slow release to manage Pimelea poisoning in cattle

2019

Conference Publication

Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic

Loh, Z. H., Hungerford, N. L., Ouwerkerk, D., Klieve, A. V. and Fletcher, M. T. (2019). Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic. 4th Queensland Annual Chemistry Symposium QACS 2019, Brisbane, QLD, Australia, 29 November 2019.

Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic

2019

Conference Publication

The Pimelea story – application of novel approaches to control toxicity in cattle

Fletcher, Mary and Ouwerkerk, Diane (2019). The Pimelea story – application of novel approaches to control toxicity in cattle. Australian Veterinary Association Queensland Division,, Gold Coast, Queensland, 22-24 March 2019.

The Pimelea story – application of novel approaches to control toxicity in cattle

2019

Conference Publication

Modelling the controlled release of toxins in a rumen environment

Yuan, Yue, Gauthier, Emilie, Hungerford, Natasha L., Ouwerkerk, Diane, Fletcher, Mary T. and Laycock, Bronwyn (2019). Modelling the controlled release of toxins in a rumen environment. 4th Queensland Annual Chemistry Symposium QACS 2019, Brisbane, QLD, Australia, 29 November 2019.

Modelling the controlled release of toxins in a rumen environment

2019

Conference Publication

In vitro bioaccessibility and transport of ascorbic and ellagic acid in Terminalia ferdinandiana (Kakadu plum) extracts

Akter, Saleha, Addepalli, Rama, Netzel, Michael E., Tinggi, Ujang, Fletcher, Mary T., Sultanbawa, Yasmina and Osborne, Simone A. (2019). In vitro bioaccessibility and transport of ascorbic and ellagic acid in Terminalia ferdinandiana (Kakadu plum) extracts. Active Integrated Matter (AIM) Conference 2019, Melbourne, VIC, Australia, 14-16 May 2019.

In vitro bioaccessibility and transport of ascorbic and ellagic acid in Terminalia ferdinandiana (Kakadu plum) extracts

2019

Conference Publication

Antimicrobial activity and ellagitannins from Terminalia ferdinandiana

Akter, Saleha, Hong, Hung Trieu, Netzel, Michael E., Tinggi, Ujang, Osborne, Simone, Fletcher, Mary and Sultanbawa, Yasmina (2019). Antimicrobial activity and ellagitannins from Terminalia ferdinandiana. TropAg2019, International Tropical Agriculture Conference, Brisbane, QLD, Australia, 11-13 November 2019. Basel, Switzerland: MDPI. doi: 10.3390/proceedings2019036081

Antimicrobial activity and ellagitannins from Terminalia ferdinandiana

2019

Conference Publication

Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic

Loh, Zhi Hung, Hungerford, Natasha L., Ouwerkerk, Diane, Gilbert, Rosalind A., Gravel, Jennifer, Minchin, Catherine M., Maguire, Anita J., Yong, Ken, Klieve, Athol and Fletcher, Mary (2019). Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic. TropAg2019, International Tropical Agriculture Conference, Brisbane, QLD, Australia, 11 - 13 November 2019.

Mitigating the effects of the toxin simplexin in pimelea poisoning of cattle by development of a microbial probiotic

2019

Conference Publication

Are toxic Pimelea secondary compounds absorbed via the intestinal lymph?

Gordon, Russell J., Hungerford, Natasha L., Laycock, Bronwyn and Fletcher, Mary T. (2019). Are toxic Pimelea secondary compounds absorbed via the intestinal lymph?. 4th Queensland Annual Chemistry Symposium QACS 2019, Brisbane, QLD, Australia, 29 November 2019.

Are toxic Pimelea secondary compounds absorbed via the intestinal lymph?

2018

Journal Article

NIRS calibration of aflatoxin in maize

Darnell, Ross E., Harvey, Jagger J., Fox, Glen P., Fletcher, Mary T., Wainaina, James, Wanjuki, Immaculate and Turner, Warwick J. (2018). NIRS calibration of aflatoxin in maize. Australian Journal of Chemistry, 71 (11), 868-873. doi: 10.1071/CH18316

NIRS calibration of aflatoxin in maize

2018

Journal Article

Release of indospicine from contaminated camel meat following cooking and simulated gastrointestinal digestion: implications for human consumption

Sultan, Saira, Giles, Cindy, Netzel, Gabriele, Osborne, Simone A., Netzel, Michael E. and Fletcher, Mary T. (2018). Release of indospicine from contaminated camel meat following cooking and simulated gastrointestinal digestion: implications for human consumption. Toxins, 10 (9) 356, 356. doi: 10.3390/toxins10090356

Release of indospicine from contaminated camel meat following cooking and simulated gastrointestinal digestion: implications for human consumption

2018

Journal Article

Learned behaviours lead to bone ingestion by phosphorus-deficient cattle

Dixon, R. M., Fletcher, M. T., Goodwin, K. L., Reid, D. J., Yong, K.W.L., McNeill, D. M. and Petherick, J. C. (2018). Learned behaviours lead to bone ingestion by phosphorus-deficient cattle. Animal Production Science, 59 (5), 921-932. doi: 10.1071/AN17251

Learned behaviours lead to bone ingestion by phosphorus-deficient cattle

2018

Journal Article

Metabolites Identified during Varied Doses of Species in Grains, and Their Correlation with Aflatoxin Levels

Falade, Titilayo D. O., Chrysanthopoulos, Panagiotis K., Hodson, Mark P., Sultanbawa, Yasmina, Fletcher, Mary, Darnell, Ross, Korie, Sam and Fox, Glen (2018). Metabolites Identified during Varied Doses of Species in Grains, and Their Correlation with Aflatoxin Levels. Toxins, 10 (5) 187, 187. doi: 10.3390/toxins10050187

Metabolites Identified during Varied Doses of Species in Grains, and Their Correlation with Aflatoxin Levels

Funding

Current funding

  • 2023 - 2025
    Harnessing the synbio potential of Australia's stingless bees, the first step
    Sugar Research Australia Limited
    Open grant
  • 2022 - 2025
    Developing cutting-edge capability for atypical saccharides in emerging and novel foods
    Queensland Health Forensic and Scientific Services
    Open grant
  • 2022 - 2027
    EAP - Biopolymers to deliver bioactive compounds that reduce enteric methane
    Meat & Livestock Australia
    Open grant

Past funding

  • 2023 - 2024
    Indospicine from the Australian plant Indigofera spicata as potential anticancer agent
    Ukraine-Australia Research Fund
    Open grant
  • 2021
    Rapid and Non-destructive Identification of Mycotoxins in Animal Feed Ingredients
    Queensland Department of Agriculture and Fisheries
    Open grant
  • 2020 - 2021
    Authentication of Australian stingless bee honey - proof of concept study
    Queensland Health
    Open grant
  • 2020 - 2021
    Optimising bioactive content of Australian stingless bee honey
    Agrifutures Australia
    Open grant
  • 2018 - 2019
    Improving nitrogen usage efficiency to reduce the environmental impact of beef cattle
    UQ-FAPESP Strategic Research Fund SPRINT
    Open grant
  • 2018 - 2023
    Nitrogen recycling as determinant for feed efficiency of Bos indicus cattle
    Meat & Livestock Australia
    Open grant
  • 2018 - 2022
    Improving beef production through management of plant toxins
    Meat & Livestock Australia
    Open grant
  • 2017 - 2018
    Analysis of environmental contaminants in Australian/Queensland honey
    Queensland Health Forensic and Scientific Services
    Open grant
  • 2017 - 2018
    Pimelea toxicity - finding potential solutions for managing cattle poisoning
    Meat & Livestock Australia
    Open grant
  • 2016 - 2018
    The risk of pyrollizidine alkaloids in Queensland honey
    Queensland Health Forensic and Scientific Services
    Open grant
  • 2016 - 2017
    Bio-actives: Value-adding to industrial hemp production
    UQ Collaboration and Industry Engagement Fund - FirstLink
    Open grant
  • 2015 - 2017
    Indospicine - managing the risk of residues in Western Australia meat
    Western Australian Department of Primary Industries and Rural Development
    Open grant
  • 2014 - 2016
    Native plant extracts for extended shelf life in corn
    Rural Industries Research & Development Corporation
    Open grant
  • 2012 - 2017
    Improved management of cattle phosphorus status through applied physiology
    Meat & Livestock Australia
    Open grant
  • 2011 - 2015
    Capacity and Action for Aflatoxin Reduction in Eastern Africa
    CSIRO
    Open grant
  • 2003 - 2004
    Linking structure to activity: identification of fruit fly sex pheromones with potential for pest management
    UQ New Staff Research Start-Up Fund
    Open grant

Supervision

Availability

Emerita Professor Mary Fletcher is:
Not available for supervision

Supervision history

Current supervision

Completed supervision

Media

Enquiries

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