Speciation Analysis, Bioavailability and Risk Assessment of Copper Complexes in Phytomedicines using Flame Atomic Absorption Spectrometry

Abstract

Octanol (n-C₈H₁₇OH), the configuration of which resembles a carbohydrate and lipid, was used as a biomembrane model, and an octanol-water system was adopted to study the distribution of copper in herbal decoctions under the acidity of saliva, gastric juice, bile and intestinal fluid. Octanol- and water-solubility were used for speciation analysis and the bioavailability assessment of copper. The influence of a combination of Aconitum carmichaeli and Paeonia lactiflora at different ratios, the acidity of the digestive site on the species, and the bioavailability and dose of copper were studied. The concentrations of copper in the original herbal materials and in n-octanol- and water-soluble fractions were determined by flame atomic absorption spectrometry following mixed acid digestion. The results showed that the digestive juice acidity, phytomedical composition, and combination ratio of phytomedicines dominated both the species present and the bioavailability of copper. The concentration of octanol-soluble copper could be used to represent the bioavailability assessment of copper in the phytomedicines, and the dosage of copper in the phytomedicines could be designed based on the level of the octanol-soluble copper and the recommended dietary allowance for copper (0.9 mg/day). Risk assessment could be examined through comparison of the level of octanol-soluble copper and the tolerable upper intake level for copper (10 mg /day).

Key words

phytomedicine - copper - Ranunculaceae - Paeoniaceae - Aconitum carmichaeli - Paeonia lactiflora

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