Elemental Composition and Chemometric Characterization of Pyrethrum Plant Materials and Insecticidal Flower Extracts

Abstract

The elemental composition of native and cultivated pyrethrum plants (Tanacetum cinerariifolium) and their insecticidal extracts obtained from dried flower heads was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The accuracy of the analytical procedure which included pressurized digestion of plant samples in HNO₃/H₂O₂ was tested by certified reference materials. Acceptable recoveries (90–110%) for the majority of elements were obtained measured in a simultaneous multi-element mode. The total pyrethrins content was determined by HPLC and it was 2.09% for cultivated plants and 1.58% for native species. The concentrations of 18 elements and pyrethrin content were subjected to statistical multivariate analysis which showed different patterns among plant parts. The roots were characterized by a combination of loadings of iron, aluminum, nickel, chromium, strontium, and barium, while the stems, leaves, and flowers showed more contributions from sodium, potassium, calcium, magnesium, phosphorus, sulfur, manganese, and copper. A higher loading of pyrethrins was the main characteristic of dried flower extracts. It was also observed that microelements such as copper, aluminum, and iron were more readily transferred into natural insecticide extracts.

Keywords:

• HPLC
• ICP-AES
• Natural insecticide
• Principal component analysis
• Trace elements

Notes

*radial mode

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