Multi-experimental characterization of selected medical plants growing in the Czech Republic

Recent Advances in the Determination of Major and Trace Elements in Plants Using Inductively Coupled Plasma Optical Emission Spectrometry

Interest in measuring major and trace elements in plants has increased in recent years because of growing concerns about the elements' contribution to daily intakes or the health risks posed by ingesting vegetables contaminated by potentially toxic elements. The recent advances in using inductively coupled plasma atomic emission spectrometry (ICP-OES) to measure major and trace elements in plant samples are reviewed in the present work. The sample preparation before instrumental determination and the main advantages and limitations of ICP-OES are described. New trends in element extraction in liquid solutions using fewer toxic solvents and microextractions are observed in recently published literature. Even though ICP-OES is a well-established and routine technique, recent innovations to increase its performance have been found. Validated methods are needed to ensure the obtaining of reliable results. Much research has focused on assessing principal figures of merit, such as limits of detection, quantification, selectivity, working ranges, precision in terms of repeatability and reproducibility, and accuracy through spiked samples or certified reference materials analysis. According to the published literature, the ICP-OES technique, 50 years after the release of the first commercially available equipment, remains a powerful and highly recommended tool for element determination on a wide range of concentrations.

Differentiation of Medicinal Plants According to Solvents, Processing, Origin, and Season by Means of Multivariate Analysis of Spectroscopic and Liquid Chromatography Data

Effects of processing and extraction solvents on antioxidant properties and other characteristics were evaluated for ten medicinal plant species originating from two different localities and two production years. A combination of spectroscopic and liquid chromatography techniques possessed data for multivariate statistics. Water, 50% (v/v) ethanol, and dimethyl sulfoxide (DMSO) were compared to select the most suitable solvent for the isolation of functional components from the frozen/dried medicinal plants. DMSO and 50% (v/v) ethanol were evaluated as more efficient for phenolic compounds and colorants extraction, while water was more useful for element extraction. Drying and extraction of herbs with 50% (v/v) ethanol was the most appropriate treatment to ensure a high yield of most compounds. The satisfactory differentiation of herbs (61.8-100%) confirmed the significant effect of the processing, geographical, and seasonal factors on target functional component concentrations. Total phenolic and total flavonoid compounds content, total antioxidant activity expressed as TAA, yellowness, chroma, and browning index were identified as the most important markers for medicinal plant differentiation.

Effects of Different Factors on Concentration of Functional Components of Aronia and Saskatoon Berries

Effects of different factors on the content of phenolics, anthocyanins, antioxidants and colour parameters in two varieties of Aronia and three varieties of Saskatoon berries were evaluated. The berries were extracted by dynamic solvent extraction using three different solvents (water, 50% ethanol (v/v) and dimethyl sulfoxide) and subsequently analysed by ultraviolet visible near infrared spectroscopy and electron paramagnetic resonance followed by chemometric analysis. The results obtained show that, dimethyl sulfoxide was the most appropriate for berries functional components isolation, and among the studied berries, Aronia exhibited the highest contents of phenolics. Besides that, varieties of Aronia melanocarpa Viking and of Amelanchier lamarckii Ballerina were selected as the cultivars with high contents of functional components. Satisfactory differentiation of berries was achieved according to extraction solvent, fruit type, variety and production years. The results obtained reveal that, phytochemical composition of Aronia and Saskatoon berries may vary depending on genotypic factors, climate, growing conditions as well as on extraction method used for their assessment. Sample processing, genotypic and seasonal factors had significant effect on the concentration of naturally occurring compounds in berries.