rXXXX American Chemical Society A dx.doi.org/10.1021/jf202083b | J. Agric. Food Chem. XXXX, XXX, 000–000 ARTICLE pubs.acs.org/JAFC Assessing the Influence of Genotype and Temperature on Polyphenol Composition in Cloudberry (Rubus chamaemorus L.) Using a Novel Mass Spectrometric Method G. J. McDougall,* ,† I. Martinussen, ‡ O. Junttila, § S. Verrall, † and D. Stewart †,|| † Environmental and Biochemical Sciences Group, Enhancing Crop Production and Utilisation Theme, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, Scotland ‡ Norwegian Institute for Agricultural and Environmental Research, Bioforsk Nord Holt, Box 2284, N-9269 Tromsø, Norway § Department of Arctic and Marine Biology, University of Tromsø, N-9037 Tromsø, Norway ) School of Life Sciences, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, Scotland b S Supporting Information ABSTRACT: A high-throughput abbreviated liquid chromatography mass spectrometric (ACMS) method was used to assess the relative influence of genotype and temperature on polyphenol composition in cloudberries. Principal component analysis (PCA) plots of the collated ACMS data showed a separation between crosses based on their female parents (Nyby or Fjellgull). Crosses with Nyby as the female parent had higher relative levels of masses assignable to certain ellagitannin derivatives. Crosses with Fjellgull had higher levels of distinctive masses assignable to quercetin derivatives (including a hydroxy-3-methylglutaroyl hexose derivative not previously identified in cloudberry) and anthocyanin derivatives. There was also a separation between samples grown at lower and higher temperatures, which was driven by m/z signals associated with ellagitannins and notably a major component, sanguiin H-6. Therefore, abbreviated MS techniques can discern genetic and/or environmental influences in polyphenol composition and can quickly assess quality in breeding programmes or in response to environmental changes. KEYWORDS: Cloudberry, metabolomics, ACMS, LCMS, polyphenol, anthocyanin, ellagitannin, quality, health ’ INTRODUCTION Cloudberry (Rubus chamaemorus L.) is a unisexual circumpo- lar species, which is collected from the wild for domestic and commercial use in Fennoscandia. It has a long history of use 1 eaten fresh or frozen in desserts and in a variety of processed formats, such as jams, wines, liqueur, sweets and syrups, and comfitures. The unique combination of color, taste, and aroma has also driven several efforts to domesticate cloudberry. 2 These ongoing efforts to maximize, exploit, and grow cloudberry, while maintaining quality, have been concentrated in the northern latitudes, principally Canada, 3 Norway, and Finland, and have included studies focusing on cultivation, 4 breeding, 2,5 and biodiversity. 6 Besides its organoleptic aspects, cloudberry is a good source of selected nutrients and human health beneficial compounds. For example, it is a rich source of vitamin C (∼0.8 mg/g fresh weight 7 ) particularly in comparison to its more common sister species, raspberry, Rubus ideaus L. (∼0.2 mg/g fresh weight 7 ). Furthermore, it is a good source of micro- and macronutrients such as Fe, Cu, Mn, Zn, Mg, K, Ca, and P. 8 More recently, however, it has been the polyphenol complement and diversity that has attracted the majority of research interest, particularly ellagitannins (ETs) and ellagic acid. 9 Polyphenols have been shown to exhibit potential benefits in model, ex vivo, and clinical interventions targeted at several areas of human health such as cancer progression, 10,11 antibacterial properties (e.g., ref 12), obesity and calorific intake, 13 and aging. 14 Although the precise mechanisms of the biological activities are still unclear, it is clear that the in vitro antioxidative effects of cloudberry are mainly due to ETs, 9 and these components have been implicated in many of the above potential health benefits. In addition, this property has been exploited in the food sector by using cloudberry extracts as natural antioxidants to retard the development of meat rancidity. 15 Clearly, any future strategies to expand the use of cloudberry, particularly in the high return, human health, and functional food/ingredient/nutraceutical sector, will need to pay close attention to any factors that impact deleteriously on the poly- phenol complement. The antioxidative activities and the chemical composition of berries are affected both by genotype and environment (e.g. refs 1618). K€ ahk€ onen et al. 9 reported significant differences in the contents of anthocyanins, flavonols, and ETs in cloudberries collected at various locations in Finland, but genetic and environ- mental influences were confounded and could not be separated. In a recent study with a female clone and a hermaphroditic clone of cloudberry, we have shown that low temperature, 912 °C, was favorable for berry size. 19 Furthermore, at the level of polyphenol classes, there was a trend to enhanced levels of total anthocyanins with decreasing temperature, but temperature Received: May 25, 2011 Accepted: September 14, 2011 Revised: September 12, 2011