* Leptosperin is a compound present only in manuka honey and provides a plausible authentication of manuka honey.
* The UMF grading system appraises natural markers found in Manuka Honey, and assures purity and quality - Leptosperin is one of the appraised markers
The discovery of Leptosperin:
The Manuka Honey Identification Project has identified a number of chemical markers unique to manuka honey. One of the four dominant markers is Leptosperin. Leptosperin provides a plausible authentication of manuka honey. Testing for authenticity
Leptosperin is characteristic of Manuka Honey. As yet this compound has not been found in the nectar of any other New Zealand flower type.
Leptosperin is present only in the nectar of the flower of the manuka plant (Leptospermum scoparium).
Leptosperin's unique presence in the nectar from the manuka flower proves that if it is present in honey then the honey can only be derived from manuka plants.
Leptosperin is abundant in Manuka Honey. The comparatively high levels of Leptosperin found in manuka honey make it straightforward to test for.
Leptosperin is relatively stable. In stability trials samples were incubated at 21, 27 and 34 degrees Celsius. Leptosperin shows little degradation over time, whereas methyglyoxal is not stable and shows a dramatic change and increase.
It is difficult to synthesise Leptosperin and thus less likely to be used in any adulteration.
Preliminary research indicates that Leptosperin may be bioactive. Work being done on this by Dr Peter Brooks and Daniel Meloncelli of the University of the Sunshine Coast
Peer-reviewed scientific publications on Leptosperin:
- Identification of Manuka Honey. Plausible authentication of manuka honey and related products by measuring leptosperin with methyl syringate. Kato Y, Fujiaka R, Ishisaka A, Nitta Y, Kitamoto N, Takimoto Y. (2014). J Agric Food Chem., 62(27), 6400-7. doi: 10.1021/jf501475h
- Authentication of Manuka Honey. Immunochemical authentication of manuka honey using a monoclonal antibody specific to a glycoside of methyl syringate. Kato Y, Araki Y, Juri M, Fujinaka R, Ishisaka A, Kitamoto N, Nitta Y, Niwa T, Takimoto Y. (2014). J Agric Food Chem., 62(44), 10672-8. doi: 10.1021/jf503464a
- Differentiation of Manuka Honey from Kanuka Honey and Jelly Bush Honey. Differentiation of Manuka Honey from Kanuka Honey and from Jelly Bush using HS-SPME-GC/MS and UHPLC-PDA-MS/MS. Beitlich, N., Koelling-Speer, I., Oelschlaegel, S., and Speer, K. (2014). J Agric Food Chem, 62(27), 6435-6444. doi: 10.1021/jf501818f
- Identification of Leptosperin. Identification of a Novel Glycoside, Leptosin, as a Chemical Marker of Manuka Honey. Yoji Kato, Natsuki Umeda, Asuna Maeda, Daiki Matsumoto, Noritoshi Kitamoto, Hiroe Kikuzaki. (March 2012). J.Agric Food Chem pp1-25. doi: 10.1021/jf300068w
- New approach: Chemical and Fluorescence profiling of NZ honeys. Bong J., et al. Food Chemistry (2017), https://dx.doi.org/10.1016/j.foodchem.2017.07.065
Abstract from paper: "New approach: Chemical and Fluorescence profiling of NZ honeys". Bong J., et al. Food Chemistry (2017)
New Zealand manuka (Leptospermum scoparium) and kanuka (Kunzea ericoides) honeys contain a unique array of chemical markers useful for chemical fingerprinting. We investigated the presence of 13 potential marker compounds in nectars of the major honey crop species. We confirmed that leptosperin, lepteridine, 2-methoxyacetophenone, and 2-methoxybenzoic acid are exclusive to manuka nectar whereas lumichrome is unique to kanuka nectar. .... Leptosperin, lepteridine .... are chemically stable over prolonged storage. ... Accordingly, leptosperin and lepteridine are definitive chemical markers for authentication of manuka honey. .... The use of leptosperin and lepteridine as fluorescence markers for manuka honey authentication is reinforced.