Azis Saifudin^1,, Habibie Habibie², Muhammad Aswad², Yasuhiro Tezuka³, Ken Tanaka⁴

Polyphenol groups have gained great interest as health-promoting and ailment-preventing agents in food ingredients. Their large range of distribution in the plant kingdom offers prospective development for many kinds of food products. From the beginning of the development processes, polyphenol group identity must be confirmed in order to guarantee the quality of their bioactivity, concentration consistency from batch to batch, and molecular stability. 1D and 2D nuclear magnetic resonance (NMR) provide robust and efficient finger printing of each polyphenol type at the skeleton level. Therefore, understanding the molecular skeleton of polyphenol types and their corresponding NMR typical signal has clearly become a necessity. However, for those in the initial involvement stage of polyphenol studies who do not possess adequate fundamental concepts in organic molecule structure, this will be a burdensome task. The goal of this review is to facilitate understanding how to use ¹H and ¹³NMR spectra to figure out the type of polyphenol based on the type of skeleton derived from possible biosynthesis pathways. Since simple polyketide polyphenol groups are very rarely found in a settled group, shikimic acid-derived compounds such as hydroxy benzoic acid and ferulic acid become the entry point to insight into more complex groups: coumarin, lignan, diarylheptanoid, Anthraquinone, phloroglucinol, xanthonoid flavonoid, stilbenoid, glycosides, and combined polyphenols with terpenoids. 2D NMR methods, in particular COSY and HMBC spectra data, are highlighted for determining the attachment site of each skeleton identity. Flavonoid, lignan, and stilbenoid oligomer possibilities possessing spatial orientation are also featured.

polyphenols, natural dietaries, healthy food product, ¹H, ¹³C NMR, HMBC