title: An Investigation of Factors that Contribute to Dihydroxyacetone Variation Observed in New Zealand Leptospermum scoparium

authors: King, Jessica

abstract: Honey derived from Leptospermum scoparium (commonly known as mānuka) is known to have anti-bacterial activity that is not entirely accounted for by the presence of hydrogen peroxide.1 This is known as non-peroxide activity (NPA). The discovery of this medical benefit has led to mānuka honey being a major export for New Zealand. In order to assure supply, mānuka trees are being investigated to determine why certain specimens yield honeys with a greater NPA than others. This might result in plantations of L. scoparium that would yield honey with a consistently high NPA. 
The compound responsible for the NPA is a 1,2-dicarbonyl known as methylglyoxal (MGO).2 The precursor to this molecule was found in nectar of the mānuka flowers and was identified as dihydroxyacetone (DHA).3 An investigation of DHA in the nectar of L. scoparium across different regions of New Zealand was carried out by Williams (2012).4 It was confirmed that trees vary within and between regions across New Zealand. 
This thesis describes different investigations into why the variation of DHA observed in various mānuka flowers is so great. Flowers were collected during flowering periods from 2011-2013 and were frozen prior to processing. The extraction method used ten flowers (10F) and samples were analysed by gas chromatography with flame ionisation detection (GC-FID). The DHA quantity was expressed with respect to the total sugar (Tsugar) in the nectar (DHA/Tsugar) in order to allow for comparison between samples.
The study by Williams (2012) was extended to include the Northland region.4 Wild L. scoparium var. incanum specimens were collected from this region and it was determined that these trees only produced a low to moderate amount of DHA/Tsugar. Williams (2012) also investigated the DHA variability of trees in close proximity to each other as these are supposed to be genetically similar.4 This study was repeated in a different region and the findings were the same; that is trees that were in close proximity to each other can have different DHA/Tsugar. 
One possibility of why DHA is observed in mānuka flowers is that it is used to combat stress as a compatible osmolyte. This was tested using chemical additives and it was found that the DHA/Tsugar varied as a result of the Tsugar as opposed to the amount of DHA. This response was cultivar dependent.
Different flower physiologies were also investigated. This included the andromonoecious nature of mānuka and the specific colour change in the hypanthium of the flower. Male flowers were found to have a larger amount of DHA/Tsugar as a result of a higher level of DHA than hermaphrodite flowers. This could suggest that DHA is being used in the hermaphrodite flowers for processes such as seed production. The DHA/Tsugar of flowers with different hypanthium colour was shown to be dependent on the variety type. The source and reason for DHA still remains unclear and therefore further study is required.

text: An Investigation of Factors that Contribute to Dihydroxyacetone Variation Observed in New Zealand Leptospermum scoparium Honey derived from Leptospermum scoparium (commonly known as mānuka) is known to have anti-bacterial activity that is not entirely accounted for by the presence of hydrogen peroxide.1 This is known as non-peroxide activity (NPA). The discovery of this medical benefit has led to mānuka honey being a major export for New Zealand. In order to assure supply, mānuka trees are being investigated to determine why certain specimens yield honeys with a greater NPA than others. This might result in plantations of L. scoparium that would yield honey with a consistently high NPA. 
The compound responsible for the NPA is a 1,2-dicarbonyl known as methylglyoxal (MGO).2 The precursor to this molecule was found in nectar of the mānuka flowers and was identified as dihydroxyacetone (DHA).3 An investigation of DHA in the nectar of L. scoparium across different regions of New Zealand was carried out by Williams (2012).4 It was confirmed that trees vary within and between regions across New Zealand. 
This thesis describes different investigations into why the variation of DHA observed in various mānuka flowers is so great. Flowers were collected during flowering periods from 2011-2013 and were frozen prior to processing. The extraction method used ten flowers (10F) and samples were analysed by gas chromatography with flame ionisation detection (GC-FID). The DHA quantity was expressed with respect to the total sugar (Tsugar) in the nectar (DHA/Tsugar) in order to allow for comparison between samples.
The study by Williams (2012) was extended to include the Northland region.4 Wild L. scoparium var. incanum specimens were collected from this region and it was determined that these trees only produced a low to moderate amount of DHA/Tsugar. Williams (2012) also investigated the DHA variability of trees in close proximity to each other as these are supposed to be genetically similar.4 This study was repeated in a different region and the findings were the same; that is trees that were in close proximity to each other can have different DHA/Tsugar. 
One possibility of why DHA is observed in mānuka flowers is that it is used to combat stress as a compatible osmolyte. This was tested using chemical additives and it was found that the DHA/Tsugar varied as a result of the Tsugar as opposed to the amount of DHA. This response was cultivar dependent.
Different flower physiologies were also investigated. This included the andromonoecious nature of mānuka and the specific colour change in the hypanthium of the flower. Male flowers were found to have a larger amount of DHA/Tsugar as a result of a higher level of DHA than hermaphrodite flowers. This could suggest that DHA is being used in the hermaphrodite flowers for processes such as seed production. The DHA/Tsugar of flowers with different hypanthium colour was shown to be dependent on the variety type. The source and reason for DHA still remains unclear and therefore further study is required.

year: 2013

title: Cartel regulation in New Zealand: Undermining the per se rule?

authors: Kingsbury, Anna

subjects: cartels

abstract: In 2010, the New Zealand Government began a process to reform and strengthen the regulation of cartels, with a focus on criminalising hard core cartels. The Organisation for Economic Co-operation and Development (OECD) has condemned hard cartels as the "most egregious violations of competition law" and recommended criminal sanctions. ¹ The New Zealand Court of Appeal has said that "[c]artel conduct has a damaging impact upon society: it results in high prices, misallocation of resources, and corrodes the incentive for firms to innovate." ²

text: Cartel regulation in New Zealand: Undermining the per se rule? In 2010, the New Zealand Government began a process to reform and strengthen the regulation of cartels, with a focus on criminalising hard core cartels. The Organisation for Economic Co-operation and Development (OECD) has condemned hard cartels as the "most egregious violations of competition law" and recommended criminal sanctions. ¹ The New Zealand Court of Appeal has said that "[c]artel conduct has a damaging impact upon society: it results in high prices, misallocation of resources, and corrodes the incentive for firms to innovate." ²

year: 2016

title: Te karanga tūturu o maieke:  Ngāti Kuri women’s taiao geographies

authors: Ringham, Sandra Lee

subjects: Māori and Indigenous geographies

abstract: This research examines the relationships, identities and sense of belonging of Māori women of within the Ngāti Kuri iwi (tribe) and te taiao (the natural world, environment, nature, country) in Te Hiku o te Ika, Far North, Aotearoa New Zealand. It shows how Ngāti Kuri women and te taiao are embedded in - yet also resist - colonial and patriarchal discourses. 
The Kaupapa Māori and Mana Wahine theoretical framework decolonises and transforms the ways in which Māori women have been represented and marginalised. Pūrākau (storywork) as a theory and methodology ensures Ngāti Kuri women’s stories are told by them and for them. Indigenous relational geography is woven into the theoretical framework to further understand Indigenous relationships to place and diverse feelings of belonging and responsibility.
Whakawhiti kōrero (research conversations), wānanga (workshops) and tipi haere (mobile wānanga) were carried out with 19 Ngāti Kuri women. Approximately 40 people from the iwi and / or scientific communities contribute to the thesis through the initiatives of the Ngāti Kuri Relationship Working Group (NKRWG), the Auckland War Memorial Museum and other research partners and as conservationists. 
Findings are organised around three themes: identities; relationships; and a sense of belonging. The first theme introduces Ngāti Kuri women’s identities as leaders and drivers of change, disrupting and dismantling the intersection of patriarchal and colonial discourse. The pūrākau of Maieke, a founding ancestress of Ngāti Kuri, brings to light the reclamation and transformation of Māori women’s identities and geographies, as defined by participants. Pre-colonisation Ngāti Kuri women had the capacity and authority to become a governing force in the daily lives of the iwi. The second theme highlights colonial and patriarchal naming of our world. Ngāti Kuri women are reconfiguring relationships and representation through the scientific naming of taonga (culturally valuable objects and species). Values and principles of kaitiakitanga (inherited guardianship) and whakawhanaugatanga (relating well to others) guide the naming process. The third theme focuses on participants’ reflections and understandings of the ways in which they sense place and feelings of belonging. Participants’ engagement with te taiao - through singing, storying and sensing place – highlights the way te taiao re-centres and transforms Ngāti Kuri women’s relationships and experiences of belonging to iwi homelands.
Importantly, the thesis concludes with a discussion of the challenges, successes and actions of Ngāti Kuri women as they continue to strive for tino rangatiratanga (self-determination), social and environmental well-being. I conceptualise new geographies that account for, and celebrate, uniquely Ngāti Kuri understandings of identities, relationships and feelings of belonging. Finally, a short creative story ends the thesis in order to show the transformative power of Ngāti Kuri women’s te taiao experiences.

text: Te karanga tūturu o maieke:  Ngāti Kuri women’s taiao geographies This research examines the relationships, identities and sense of belonging of Māori women of within the Ngāti Kuri iwi (tribe) and te taiao (the natural world, environment, nature, country) in Te Hiku o te Ika, Far North, Aotearoa New Zealand. It shows how Ngāti Kuri women and te taiao are embedded in - yet also resist - colonial and patriarchal discourses. 
The Kaupapa Māori and Mana Wahine theoretical framework decolonises and transforms the ways in which Māori women have been represented and marginalised. Pūrākau (storywork) as a theory and methodology ensures Ngāti Kuri women’s stories are told by them and for them. Indigenous relational geography is woven into the theoretical framework to further understand Indigenous relationships to place and diverse feelings of belonging and responsibility.
Whakawhiti kōrero (research conversations), wānanga (workshops) and tipi haere (mobile wānanga) were carried out with 19 Ngāti Kuri women. Approximately 40 people from the iwi and / or scientific communities contribute to the thesis through the initiatives of the Ngāti Kuri Relationship Working Group (NKRWG), the Auckland War Memorial Museum and other research partners and as conservationists. 
Findings are organised around three themes: identities; relationships; and a sense of belonging. The first theme introduces Ngāti Kuri women’s identities as leaders and drivers of change, disrupting and dismantling the intersection of patriarchal and colonial discourse. The pūrākau of Maieke, a founding ancestress of Ngāti Kuri, brings to light the reclamation and transformation of Māori women’s identities and geographies, as defined by participants. Pre-colonisation Ngāti Kuri women had the capacity and authority to become a governing force in the daily lives of the iwi. The second theme highlights colonial and patriarchal naming of our world. Ngāti Kuri women are reconfiguring relationships and representation through the scientific naming of taonga (culturally valuable objects and species). Values and principles of kaitiakitanga (inherited guardianship) and whakawhanaugatanga (relating well to others) guide the naming process. The third theme focuses on participants’ reflections and understandings of the ways in which they sense place and feelings of belonging. Participants’ engagement with te taiao - through singing, storying and sensing place – highlights the way te taiao re-centres and transforms Ngāti Kuri women’s relationships and experiences of belonging to iwi homelands.
Importantly, the thesis concludes with a discussion of the challenges, successes and actions of Ngāti Kuri women as they continue to strive for tino rangatiratanga (self-determination), social and environmental well-being. I conceptualise new geographies that account for, and celebrate, uniquely Ngāti Kuri understandings of identities, relationships and feelings of belonging. Finally, a short creative story ends the thesis in order to show the transformative power of Ngāti Kuri women’s te taiao experiences.

year: 2022