Honey Research Unit Publications

The Honey Research Unit’s publications showcase robust and collaborative research advancing scientific knowledge in and of New Zealand’s apiculture sector.

If you are interested in our research or would like to discuss collaboration or support, contact the Honey Research Unit or fill in our enquiry form.

Honey

Graphical Discrimination of New Zealand Honey from International Honey Using Elemental Analysis. Grainger, M. N. C.; Klaus, H.; Hewitt, N.; Gan, H.; French, A. D. Biological Trace Element Research 2024, 202 (2), 754-764.
DOI: doi.org/10.1007/s12011-023-03680-6

Accelerated loss of diastase in mānuka honey: Investigation of mānuka specific compounds. Bell, A. R.; Grainger, M. N. C. Food Chemistry 2023, 426, 136614.
DOI: doi.org/10.1016/j.foodchem.2023.136614

C4 sugar adulteration methodology: Understanding false-positive results for mānuka honey. Grainger, M. N. C. Food Chemistry Advances 2022, 1, 100128.
DOI: doi.org/10.1016/j.focha.2022.100128

Investigation of inorganic elemental content of honey from regions of North Island, New Zealand. Grainger, M. N. C.; Klaus, H.; Hewitt, N.; French, A. D. Food Chemistry 2021, 361, 130110.
DOI: doi.org/10.1016/j.foodchem.2021.130110

Optimised approach for small mass sample preparation and elemental analysis of bees and bee products by inductively coupled plasma mass spectrometry. Grainger, M. N. C.; Hewitt, N.; French, A. D. Talanta 2020, 120858.
DOI: doi.org/10.1016/j.talanta.2020.120858

Kinetics of conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part V – The rate determining step. Owens, A.; Lane, J. R.; Manley-Harris, M.; Marie Jensen, A.; Jørgensen, S. Food Chemistry 2019, 276, 636-642.
DOI: doi.org/10.1016/j.foodchem.2018.10.039

Kinetics of conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part IV – Formation of HMF. Grainger, M. N. C.; Owens, A.; Manley-Harris, M.; Lane, J. R.; Field, R. J. Food Chemistry 2017, 232, 648-655.
DOI: doi.org/10.1016/j.foodchem.2017.04.066

Kinetics of conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part III – A model to simulate the conversion. Grainger, M. N. C.; Manley-Harris, M.; Lane, J. R.; Field, R. J. Food Chem. 2016, 202, 500-506.
DOI: doi.org/10.1016/j.foodchem.2016.02.032

Kinetics of the conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part II – Model systems. Grainger, M. N. C.; Manley-Harris, M.; Lane, J. R.; Field, R. J. Food Chemistry 2016, 202, 492-499.
DOI: doi.org/10.1016/j.foodchem.2016.02.030

Kinetics of conversion of dihydroxyacetone to methylglyoxal in New Zealand mānuka honey: Part I – Honey systems. Grainger, M. N. C.; Manley-Harris, M.; Lane, J. R.; Field, R. J. Food Chemistry 2016, 202, 484-491.
DOI: doi.org/10.1016/j.foodchem.2016.02.029

Isolation of maltol glucoside from the floral nectar of New Zealand mānuka (Leptospermum scoparium). Adams, C. J.; Grainger, M. N. C.; Manley-Harris, M. Food Chemistry 2015, 174 (Supplement C), 306-309.
DOI: doi.org/10.1016/j.foodchem.2014.11.073

The Unique Mānuka Effect: Why New Zealand Mānuka Honey Fails the AOAC 998.12 C-4 Sugar Method. Rogers, K. M.; Grainger, M.; Manley-Harris, M. Journal of Agricultural and Food Chemistry 2014, 62 (12), 2615-2622.
DOI: doi.org/10.1021/jf404767b

Effect of high pressure processing on the conversion of dihydroxy acetone to methylglyoxal in New Zealand mānuka (Leptospermum scoparium) honey and models thereof. Grainger, M. N. C.; Manley-Harris, M.; Fauzi, N. A. M.; Farid, M. M. Food Chemistry 2014, 153, 134-139.
DOI: https://doi.org/10.1016/j.foodchem.2013.12.017

Analysis of the flavonoid component of bioactive New Zealand mānuka (Leptospermum scoparium) honey and the isolation, characterisation and synthesis of an unusual pyrrole. Chan, C. W.; Deadman, B. J.; Manley-Harris, M.; Wilkins, A. L.; Alber, D. G.; Harry, E. Food Chemistry 2013, 141 (3), 1772-1781.
DOI: doi.org/10.1016/j.foodchem.2013.04.092.

A convenient analysis for dihydroxyacetone and methylglyoxal in Australian honeys. Windsor, S.; Pappalardo, M.; Brooks, P.; Williams, S.; Manley-Harris, M. Journal of Pharmacognosy and Phytotherapy 2012, 4 (1), 6-11.
DOI: doi.org/10.5897/JPP11.025.

The controlled in vitro susceptibility of gastrointestinal pathogens to the antibacterial effect of mānuka honey. Lin, S.; Molan, P.; Cursons, R. European Journal of Clinical Microbiology & Infectious Diseases 2010, 1-6.
DOI: doi.org/10.1007/s10096-010-1121-x

The origin of methylglyoxal in New Zealand mānuka (Leptospermum scoparium) honey. Adams, C. J.; Manley-Harris, M.; Molan, P. C. Carbohydrate Research 2009, 344 (8), 1050-1053.
DOI: doi.org/10.1016/j.carres.2009.03.020

Corrigendum to "Isolation by HPLC and characterization of the bioactive fraction of New Zealand mānuka (Leptospermum scoparium) honey". Adams, C. J.; Boult, C. H.; Deadman, B. J.; Farr, J. M.; Grainger, M. N. C.; Manley-Harris, M.; Snow, M. J. [Carbohydrate Research vol 343 (2008) pg 651], Carbohydrate Research 2009, 344 (18), 2609-2609.
DOI: doi.org/10.1016/j.carres.2009.08.008

Isolation by HPLC and characterisation of the bioactive fraction of New Zealand mānuka (Leptospermum scoparium) honey. Adams, C. J.; Boult, C. H.; Deadman, B. J.; Farr, J. M.; Grainger, M. N. C.; Manley-Harris, M.; Snow, M. J. Carbohydrate Research 2008, 343 (4), 651-659.
DOI: doi.org/10.1016/j.carres.2007.12.011

A review of Leptospermum scoparium (Myrtaceae) in New Zealand. Stephens, J. M. C.; Molan, P. C.; Clarkson, B. D. New Zealand Journal of Botany 2005, 43, 431 - 449.
DOI: doi.org/10.1080/0028825X.2005.9512966

On the nature of non-peroxide antibacterial activity in New Zealand mānuka honey. Snow, M. J.; Manley-Harris, M. Food Chemistry 2004, 84 (1), 145-147.
DOI: doi.org/10.1016/S0308-8146(03)00258-9

Clinical usage of honey as a wound dressing: An update. Molan, P. C.; Betts, J. A. Journal of Wound Care 2004, 13 (9), 3535-3356.
DOI: doi.org/10.12968/jowc.2004.13.9.26708

The effect of dilution on the rate of hydrogen peroxide production in honey and its implications for wound healing. Bang, L. M.; Buntting, C.; Molan, P. Journal of Alternative & Complementary Medicine 2003, 9 (2), 267-273.
DOI: doi.org/10.1089/10755530360623383

The sensitivity to honey of Gram-positive cocci of clinical significance isolated from wounds. Cooper, R. A.; Molan, P. C.; Harding, K. G. J. Appl. Microbiol. 2002, 93 (5), 857-863.
DOI: 10.1046/j.1365-2672.2002.01761.x.

Extractives from New Zealand Honeys. 5. Aliphatic Dicarboxylic Acids in New Zealand Rewarewa (Knightea excelsa) Honey. Wilkins, A. L.; Lu, Y. Journal of Agricultural and Food Chemistry 1995, 43 (12), 3021-3025.
DOI: doi.org/10.1021/jf00060a006

Susceptibility of Helicobacter pylori to the antibacterial activity of mānuka honey. N al Somal, N.; Coley, K. E.; Molan, P. C.; Hancock, B. M. Journal of the Royal Society of Medicine 1994, 87, 9-12.
DOI: doi.org/10.1177/014107689408700106

Extractives from New Zealand honeys. 4. Linalool derivatives and other components from nodding thistle (Carduus nutans) honey. Wilkins, A. L.; Lu, Y.; Tan, S. T. Journal of Agricultural and Food Chemistry 1993, 41 (6), 873-878.
DOI: doi.org/10.1021/jf00030a006

Extractable organic substances from New Zealand unifloral mānuka (Leptospermum scoparium) honeys. Wilkins, A. L.; Lu, Y.; Molan, P. J. Apic. Res. 1993, 32 (1), 3-9.
DOI: doi.org/10.1080/00218839.1993.11101281

The antibacterial activity of honey 2. Variation in the potency of the antibacterial activity. Molan, P. Bee World 1992, 73 (2), 59-76.
DOI: doi.org/10.1080/0005772X.1992.11099118

The Antibacterial activity of honey 1. The nature of the antibacterial activity. Molan, P. Bee World 1992, 73 (1), 5-28.

A survey of the antibacterial activity of some New Zealand honeys. Allen, K. L.; Molan, P. C.; Reid, G. M. Journal of Pharmacy and Pharmacology 1991, 43 (12), 817-822, Article.
DOI: doi.org/10.1111/j.2042-7158.1991.tb03186.x Scopus.

Extractives from New Zealand honeys. 3. Unifloral thyme and willow honey constituents. Tan, S. T.; Wilkins, A. L.; Holland, P. T.; McGhie, T. K. Journal of Agricultural and Food Chemistry 1990, 38 (9), 1833-1838.
DOI: doi.org/10.1021/jf00099a010 (acccessed 2014/08/14).

Identification of some antibacterial constituents of New Zealand mānuka honey. Russell, K. M.; Molan, P. C.; Wilkins, A. L.; Holland, P. T. J. Agric. Food Chem. 1990, 38 (1), 10-13.
DOI: doi.org/10.1016/j.talanta.2023.124647

Identification of some antibacterial constituents of New Zealand mānuka honey. Russell, K. M.; Molan, P. C.; Wilkins, A. L.; Holland, P. T. Journal of Agricultural and Food Chemistry 1990, 38 (1), 10-13.
DOI: doi.org/10.1021/jf00091a002

Extractives from New Zealand unifloral honeys. 2. Degraded carotenoids and other substances from heather honey. Tan, S. T.; Wilkins, A. L.; Holland, P. T.; McGhie, T. K. Journal of Agricultural and Food Chemistry 1989, 37 (5), 1217-1221.
DOI: doi.org/10.1021/jf00089a004

A Chemical Approach to the Determination of Floral Sources of New Zealand Honeys. Tan, S. T.; L., W. A.; C., M. P.; T., H. P.; and Reid, M. J. Apic. Res. 1989, 28 (4), 212-222.
DOI: doi.org/10.1080/00218839.1989.11101187

Extractives from New Zealand honeys. 1. White clover, mānuka and kanuka unifloral honeys. Tan, S. T.; Holland, P. T.; Wilkins, A. L.; Molan, P. C. Journal of Agricultural and Food Chemistry 1988, 36 (3), 453-460.
DOI: doi.org/10.1021/jf00081a012

Non-peroxide antibacterial activity in some New Zealand honeys. Molan, P.; Russell, K. M. J. Apic. Res. 1988, 27, 62-67.
DOI: doi.org/10.1080/00218839.1988.11100783

Past Honey Reseach by Peter Molan

A large body of research was carried out by Dr Molan and collaborators on the antibacterial properties of mānuka honey and its use as a dressing to heal wounds.

Trees

Host selection is not a universal driver of phyllosphere community assembly among ecologically similar native New Zealand plant species. Noble, A. S.; Abbaszadeh, J.; Lee, C. K. Microbiome 2025, 13 (1), Article.
DOI: doi.org/10.1186/s40168-024-02000-x

A phosphatase gene is linked to nectar dihydroxyacetone accumulation in mānuka (Leptospermum scoparium). Grierson, E. R. P.; Thrimawithana, A. H.; van Klink, J. W.; Lewis, D. H.; Carvajal, I.; Shiller, J.; Miller, P.; Deroles, S. C.; Clearwater, M. J.; Davies, K. M.; et al. New Phytologist 2024, 242 (5), 2270-2284.
DOI: doi.org/10.1111/nph.19714

Nectary photosynthesis contributes to the production of mānuka (Leptospermum scoparium) floral nectar. Clearwater, M. J.; Noe, S. T.; Manley-Harris, M.; Truman, G.-L.; Gardyne, S.; Murray, J.; Obeng-Darko, S. A.; Richardson, S. J. New Phytologist 2021, 232 (4), 1703-1717.
DOI: doi.org/10.1111/nph.17632

A core phyllosphere microbiome exists across distant populations of a tree species indigenous to New Zealand. Noble, A. S.; Noe, S.; Clearwater, M. J.; Lee, C. K. PLoS One 2020, 15 (8), e0237079.
DOI: doi.org/10.1371/journal.pone.0237079

Floral nectar of wild mānuka (Leptospermum scoparium) varies more among plants than among sites. Noe, S.; Manley-Harris, M.; Clearwater, M. J. New Zealand Journal of Crop and Horticultural Science 2019, 1-15.
DOI: doi.org/10.1080/01140671.2019.1670681

Influence of genotype, floral stage, and water stress on floral nectar yield and composition of mānuka (Leptospermum scoparium). Clearwater, M. J.; Revell, M.; Noe, S.; Manley-Harris, M. Annals of Botany 2018, 121 (3), 501-512.
DOI: doi.org/10.1093/aob/mcx183

Regional, annual, and individual variations in the dihydroxyacetone content of the nectar of ma̅nuka (Leptospermum scoparium) in New Zealand. Williams, S.; King, J.; Revell, M.; Manley-Harris, M.; Balks, M.; Janusch, F.; Kiefer, M.; Clearwater, M.; Brooks, P.; Dawson, M. J Agric Food Chem 2014, 62 (42), 10332-10340.
DOI: doi.org/10.1021/jf5045958

Propolis

Composition and bioactivity of propolis derived from New Zealand native forest. Manley-Harris, M.; Grainger, M. N. C.; Peters, L. M.; Te Rire-McNeil, S. T. Fitoterapia 2025, 181, 106412.
DOI: doi.org/10.1016/j.fitote.2025.106412

HPLC and GC-MS identification of the major organic constituents in New Zeland propolis. Phytochemistry Markham, K. R.; Mitchell, K. A.; Wilkins, A. L.; Daldy, J. A.; Lu, Y. 1996, 42 (1), 205-211.
DOI: doi.org/10.1016/0031-9422(96)83286-9

Theses

Honey

Thomas, E., Characterisation of the aroma profiles of New Zealand monofloral honeys, MSc, The University of Waikato, Hamilton, New Zealand, 2023

Bell, A, An investigation of low diastase activity in mānuka honey, MSc, The University of Waikato, Hamilton, New Zealand, 2023.

Swears, R., "The Bee on Honey-Dew Hath Fed": Carbohydrate composition and prebiotic potential of an Australian commercial honey and some New Zealand honeydew honeys, MSc, The University of Waikato, Hamilton, New Zealand, 2020.

Owens, A., The kinetics of the dissociation of dihydroxyacetone dimer in aprotic media, MSc, The University of Waikato, Hamilton, New Zealand, 2016.

Grainger, M. N. C., Kinetics of conversion of dihydroxyacetone to methylglyoxal in honey. Ph.D, The University of Waikato, Hamilton, New Zealand, 2015.

Lloyd, A., Analysis of Amino Acids in Mānuka Honey, MSc, The University of Waikato, Hamilton, New Zealand, 2015.

Chan, C., Isolation, Characterization and Synthesis of a Phenyl-substituted Pyrrole Isolated from the Flavonoid Fraction of Mānuka Honey, MSc, The University of Waikato, Hamilton, New Zealand, 2011.

Trees

Nobel, A., Exploring the mānuka phyllosphere microbiome, Ph.D, The University of Waikato, Hamilton, New Zealand, 2024.

Noble, A., Environmental and biogeographical drivers of the Leptospermum scoparium (mānuka) phyllosphere microbiome, MSc, The University of Waikato, Hamilton, New Zealand, 2018.

King, J., An Investigation of Factors that Contribute to Dihydroxyacetone Variation Observed in New Zealand Leptospermum scoparium, MSc, The University of Waikato, Hamilton, New Zealand, 2013.

Williams, S., A Survey of Dihydroxyacetone in Nectar of Leptospermum Scoparium from Several Regions of New Zealand, MSc, The University of Waikato, Hamilton, New Zealand, 2012.

Media

Podcasts and webinars

Mānuka is A Buzzworthy Functional Food for Health, Grainger, M., 2025, Webinar,

Podcast Episode 281: What’s All the Buzz About? The Health Benefits of Mānuka Honey – Dr. Megan Grainger & Beekeeper James Jeffery Sound Bites, Grainger M., 2025.

Honey fingerprints and plant powers, Grainger M., RNZ, 2022 .

Videos

Megan Grainger – Emerging Scientist, Grainger, M., 2022 Dr., The Kudos Science Trust YouTube.   

Magazines and interviews

20 minutes with – Changing NZ's Honey Industry, Grainger, M. Sequeira, J., Ed.; F+BTech, May 2025; pp 32-33.

Leading promising research in NZ mānuka honey, Grainger, M. Sequeira, J., Ed.; Supermarket News, May 2025; pp 24-25.

Can Mānuka Honey Avoid the Tait of ‘Adulteration’? Grainger, M. Dawkins, P., Ed.; Apiarist's Advocate, May, 2023

Megan Grainger – Emerging Scientist, Grainger, M., 2022 Dr., The Kudos Science Trust YouTube.

Television

In Rural Delivery, Grainger, M. N. C. Cvitanovich, J., Ed.; Series 13, Episode 6: TV 1, 2017.

Magazines articles

NZ Beekeepers Magazine: You can subscribe for free.

Move over mānuka – here are 5 other delicious native NZ honeys to try this summer In The Conversation, Grainger, M., 2024; December

Testing nectar to select Mānuka trees for high-grade honey, New Zealand. Grainger, M. N. C. New Zealand Beekeeper, 2016; Vol. December 2016.

Assessing the potential of your hive site. Grainger, M. N. C. Apiculture Conference, Rotorua, New Zealand, 19-21 June 2016, 2016.

C4 sugar analysis. Grainger, M. New Zealand Beekeeper, New Zealand Beekeeper, 2015; July, pp 13-14.

The explaination of why the level of UMF varies in mānuka honey. Stephens, J.; Molan, P. C. New Zealand BeeKeeper, South City Print: New Zealand BeeKeeper, 2008; Vol. March, pp 17-21.

Improvements to the UMF assay. Molan, P. C. New Zealand Bee Keeper 2008, 16 (7), 24-25.

An explanation of why the MGO level in mānuka honey does not show the antibacterial activity. Molan, P. C. New Zealand Bee Keeper 2008, 16 (4), 11-13.

Current honey research at the University of Waikato. Molan, P. C. The New Zealand Bee Keeper 2008, 16 (7), 20-21.

World Wide Wounds. Molan, P. C. 2001. (accessed 2011 5 March 2011).