Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/21/2018
Publication Date: 2/18/2019
Citation: Klevorn, C.M., Dean, L.L., Johanningsmeier, S.D. 2019. Metabolite profiles of raw peanut seeds reveal differences between market-types. Journal of Food Science. 84(3):397-405. https://doi.org/10.1111/1750-3841.14450.
Interpretive Summary: Growing seeds produce many small molecular compounds that have the potential to be beneficial to human health and wellness. This paper reports the first known survey of these compounds present in raw peanut seeds of both the runner and the virginia cultivars. Many of the compounds found are related to the formation of proteins and fats in raw peanuts. Some of the compounds such as tocopherols (Vitamin E) are known to be required by humans. Others such as amino acid and nucleic acid components are of value. From these chemical profiles, differences between runner and virginia type peanuts were found and this could be useful information for the development of peanut varieties.
Technical Abstract: The peanut is cultivated worldwide both for oil as well as for edible seed. In contrast to other major production regions, the United States peanut crop predominantly enters the edibles market. The composition of the raw peanut seed has the potential to be further improved through traditional breeding methods yet very little remains known about its metabolome. A comprehensive metabolomic profile of both raw runner and virginia-type peanuts was elucidated for the first time. Qualitative metabolomic data was obtained through use of a multi-platform approach including (RP)/UPLC-MS/MS and HILIC/UPLC-MS/MS and coupled with quantitation of fatty acids, free amino acids, and tocopherols. A total of 365 metabolites were identified against authentic standards with 52 found to be significantly different between market types (P < 0.05). Virginia-type peanuts were characterized by higher levels of gamma-glutamylalanine, oxylipins, purine metabolites, and alpha-ketoglutarate derived members of the glutamate family of amino acids, while Runner-type peanuts were differentiated by their ethylmalonate and eicosenoate content. This study represents the most comprehensive analysis of the raw peanut seed to date, providing insight into the breadth of small molecules present in the peanut. The new information presented here will augment the toolbox for peanut quality improvement.