Integrative study of Anchusa italica Retz flower’s microstructure and chemical composition

The unique structural features of Anchusa italica Retz (A. italica Retz) flowers were revealed at different scales through tissue sectioning and microstructural observations of the flower powder. High-resolution imaging of the fine structure and fracture of the sample surface was performed using scanning electron microscopy (SEM) to obtain detailed information about the surface morphology and microstructure. The chemical composition of the samples was analysed via ultra-performance liquid chromatography quadrupole-orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS). Infrared and near-infrared spectroscopy were employed to elucidate the vibrational characteristics of the functional groups in the sample. Characteristic structures, including nonglandular hairs, ducts, epidermal cells, and pollen grains, were revealed through microscopic and SEM analyses. A diverse array of bioactive substances, including flavonoids, saponins, phenylpropanoids, and polyphenolic compounds, was identified. Among these substances, rosmarinic acid (Ros A) had the highest relative content, reaching 39.85%. The infrared spectral scans had high stability for multiple batches of samples, with discernible characteristic peaks at 1434 cm^-1, 1619 cm^-1, 2923 cm^-1, and 3440 cm^-1. A comprehensive investigation and an analysis of the microstructure and chemical composition of A. italica Retz flowers were performed, and cross-scale analysis was employed to expand and supplement the current understanding of the morphological, histological, and chemical diversity of the plant. This analysis provides a scientific basis for the potential medicinal value of this plant and a theoretical foundation for subsequent in-depth research.