Study on quality control methods of natural products using relative molar sensitivity with an emphasis on accuracy

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20735
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0801:Pharmaceutical sciences and related fields
• Research Institution: National Institute of Health Sciences
• Principal Investigator: Masumoto Naoko 国立医薬品食品衛生研究所, 食品添加物部, 主任研究官 (70754034)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: 相対モル感度 / クロロゲン酸 / カフェ酸 / クロマトグラフィー / HPLC-PDA

Outline of Final Research Achievements

The RMS method, a quantitative method using the relative molar sensitivity (RMS) of an analyte to reference material (RMS reference), was studied. Chlorogenic acid and its relatives (CGAs) are esters between quinic acid and cinnamic acid derivatives, and many compound types exist depending on the type and position of the cinnamic acid derivatives bonded to the quinic acid. Because quinic acid has almost no UV absorption, RMSs of CGAs used for HPLC/PDA could be predicted from the type and number of cinnamic acid derivatives, which are chromophores. RMSs of chlorogenic acid isomers, which differed in the bonding position, were almost identical. The RMS was almost twice as large when the number of cinnamic acid derivatives binding to quinic acid was two as when it was one. However, it was about 5% less than twice when steric hindrance was predicted. The results suggest that the RMS of a compound could be predicted from the RMSs of its analogs.

Free Research Field

分析化学、生薬・天然物

Academic Significance and Societal Importance of the Research Achievements

我々は古くから様々な天然資源を薬や食品として活用しており，これらの有効かつ安全な活用には，含まれる有用成分や有害成分の量を正しく把握し適切に用いることが肝要である．天然物のような多成分系試料中の成分の定量では定量用標品の入手が障壁となり不正確な定量値しか得られない場合も少なくない．このような課題の解決策の一つとしてRMS法が用いられているが，構造とRMSとの関係はどのようなものがあるか，装置間差はどうかといった学術的な情報が十分に集められているとは言いがたい．本研究の成果を含めRMS法の開発が進むことは，定量可能な成分の幅が広がり，人々がより有効かつ安全に天然資源を活用できることにつながる．