Identification and Characterization of Foliar Polyphenolic Composition in Sweetpotato (Ipomoea batatas L.) Genotypes

Abstract

Trials over two years were conducted using 1389 sweetpotato (Ipomoea batatas L.) genotypes collected from all over the world to characterize the polyphenolic composition in sweetpotato leaves. Wide variation was observed in relation to their total and individual leaf polyphenolic constituents. In all genotypes studied, the total polyphenol contents of sweetpotato leaf ranged from 1.42 to 17.1 g/100 g dry weight. The six different polyphenolic compounds were identified and quantified by NMR, FABMS, and RPHPLC analysis procedures. This is the first report of polyphenolic compositions in sweetpotato leaves. The relative levels of polyphenolic acids in sweetpotato leaves were as follows: 3,5-di-O-caffeoylquinic acid > 4,5-di-O-caffeoylquinic acid > chlorogenic acid (3-O-caffeoylquinic acid) > 3,4-di-O-caffeoylquinic acid > 3,4,5-tri-O-caffeoylquinic acid > caffeic acid. The highest 3,4,5-tri-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid occurred at 221 and 1183.30 mg/100 g dry weight, respectively.

Free Radical Scavenging and Hepatoprotective Actions of the Medicinal Herb, Crassocephalum crepidioides from the Okinawa Islands

“…Thus the structure of six fractions obtained was identified by UV, 1 H-NMR and 13 C-NMR spectra by comparision with an authentic sample or the reported compound. 27,28) Statistical Analyses Data were expressed as the meanϮ S.D. The significance of difference was evaluated using Student's t-test 29) and pϽ0.05 was taken as significant.…”

Simple High-yield Purification of 3,4,5-Tri-O-caffeoylquinic Acid from Sweetpotato (Ipomoea batatas L.) Leaf and Its Inhibitory Effects on Aldose Reductase

“…We found that sweetpotato leaves contain large amounts of polyphenols and identified caffeic acid (CA) and five types of caffeoylquinic acid (CQA) derivatives, mono-, diand triCQAs (Islam et al, 2002). Mono-and diCQAs are ubiquitously present in plants.…”

Single-laboratory validation for the determination of caffeic acid and seven caffeoylquinic acids in sweet potato leaves

“…11) Our previous experiments revealed that sweet potato leaves have a higher CQA content compared to other major commercial vegetables. 4) Our previous experiments also showed that the order of the anti-mutagenicity of CQAs was as follows: 3,4,5-triC-QA > diCQAs > 5-CQA. 12) About a decade ago, NARO/KARC developed "Suioh", a sweet potato cultivar, whose leaves are also edible.…”

“…Especially, coffee beans (27.9-52.0 g kg −1 dw), eggplant plant fruits (14.1-28.0 g kg −1 dw), mate tea (4.8-24.9 g kg −1 dw), and sweet potato leaves (14.2-171 g kg −1 dw) contained high amount of CQAs. [1][2][3][4] In addition, it is estimated that humans consume up to 1.0 g of CQAs per day. 5) CQAs have several beneficial properties, and in in vitro and in vivo experiments, have been found to induce anti-oxidant, 6) anti-hyperglycemic, 7) anti-melanogenic, 8) and neuroprotective effects.…”