Chemical and Pharmaceutical Bulletin
Online ISSN : 1347-5223
Print ISSN : 0009-2363
ISSN-L : 0009-2363
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Simple and Rapid Evaluation of the Unique Manuka Factor in Manuka Honey Using Fluorescence Fingerprints and Principal Component Analysis
Koji KarasawaMasatoshi TakakuraSaori KatoMomoha AkatsukaMasaru Kato
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2020 Volume 68 Issue 8 Pages 762-765


The excellent antibacterial activity of manuka honey has been well-documented and is often evaluated according to the unique manuka factor (UMF) index. UMF is determined by an assay based on a bacterial culture, which is time-consuming and does not allow for quantitative analysis. This study developed a simple and rapid method for UMF evaluation using fluorescence fingerprints, principal component analysis (PCA), and partial least squares (PLS) regression. Manuka honey samples were diluted four times with water and fluorescence was observed at three wavelength combinations, namely 260–300 (excitation; ex) to 370 (emission; em) nm, 340 (ex) to 480 nm (em), and 440 (ex) to 520 nm (em), that are mainly attributed to lepteridine, leptosperin, 2-methoxybenzoic acid, and N-methyl phenazinium. Analyzing fluorescence fingerprints using PCA and PLS regression provided a reliable evaluation of the UMF in manuka honey and could be used to differentiate between manufacturers.

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© 2020 The Pharmaceutical Society of Japan
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