Application of numerical methods to thin-layer chromatographic investigation of the main components of chamomile (Chamomilla recutita (L.) Rauschert) essential oil

Differences in the Aroma Profile of Chamomile (Matricaria chamomilla L.) after Different Drying Conditions

This experiment was conducted to examine the influence of drying methods on the essential oil of chamomile (Matricaria chamomilla L.) and its chemical composition. Chamomile flower heads were dried using five different methods: sunlight for 72 h; shade for 1 week; oven at 40 °C for 72 h; solar dryer for 72 h; and microwave for 5 min. Drying methods had slight and nonsignificant impacts on dry biomass of flower heads. The highest percentages of oil in flowers (0.35–0.50%) were observed after solar-drying methods, and the lowest percentage of oil was found after microwave drying (0.24–0.33%). Drying methods significantly influenced the number of identified compounds. The maximum was identified after solar drying (21 compounds), while the lowest was identified after microwave drying (13 compounds), which revealed the solar ability to preserve compounds in contrast to microwave, which crushed the compounds. Major compounds were α-bisabolol oxide A (33.0–50.5%), (Z)-tonghaosu (10.0–18.7%), α-bisabolol oxide B (8.2–15.4%), α-bisabolone oxide A (5.4–14.6%), and chamazulene (1.9–5.2%) of essential oil. Drying methods clearly affected major compounds’ content as the lowest α-bisabolol oxide A was after sun drying, and the lowest α-bisabolol oxide B was after solar drying. (Z)-tonghaosu increased during drying compared to fresh flowers. Solar drying maintained higher chamazulene content (3.0%) compared to other drying methods. The results of this study suggest that drying under the shady conditions preserved chemical composition of essential oil with higher α-bisabolol content compared to other drying methods.

From functional food to medicinal product: systematic approach in analysis of polyphenolics from propolis and wine

In the last decade we have been working on standardization of propolis extract and determination of active constituents of wine those are rich in polyphenolics and have nutritional as well as therapeutic value. Here we are summarizing our results and providing overview on systematic approach how to analyse natural products rich in flavonoids and phenolic acids.Chromatographic methods (thin layer chromatography and high performance liquid chromatography) were used for identification, quantification, and characterization of individual flavonoid or phenolic acid. Total content of active constituents and antioxidant activity were determined by spectrophotometry. Pharmacokinetic parameters were determined by high performance liquid chromatography and using appropriate software. Quantitative structure-activity relationship study of antioxidant activity was conducted, as well as assessment of prolonged propolis supplementation on antioxidative status of organism.Thin layer chromatography-densitometry has been proven as quick and reliable method for standard analysis of propolis and wine; the best mobile phase being chloroform - methanol - formic acid (98-100%) in ratio 44 : 3.5 : 2.5 (v/v). Higher number of polyphenolics was determined by high performance liquid chromatography; 15 compared to 9 by thin layer chromatography. Interactions in situ with acetylsalicylic acid were detected with most of polyphenolics analysed. Plasma protein binding and blood-barrier penetration was greatest for flavone. The interactions with human serum albumin have been grater than 95% for all flavonoids analysed. The prolonged propolis consumption increased superoxide dismutase activity.The necessity of standardization of natural products and their registration as functional nutraceuticals demand easy, quick and inexpensive methods of analysis. In this work we provided overview of analytical part for polyphenolics that could be used as data for possible registration of final products either as functional food or medicinal product.This feature introduces the readers to the authors' research through a concise overview of the selected topic. Reference to important work from others in the field is included.

Application of self-organizing maps for the classification of chromatographic systems and prediction of values of chromatographic quantities

The applicability of self-organizing maps (SOM) for the classification of chromatographic systems or components of chromatographic systems based on data taken from literature is shown. The SOM approach is compared to dendrogram and principal components analysis (PCA) approaches. It has been shown that the distance between classified objects could reveal linear correspondence with quantity to be optimized, e.g. resolution, so it can be applied in the chromatographic method development. SOMs can also be applied for prediction of chromatographic quantities. It is shown that SOM-based response surface modeling is comparable to triangular presentation of mobile phase composition response surfaces.

Optimization of TLC analysis of flavonoids and phenolic acids of Helleborus atrorubens Waldst. et Kit

Numerical methods for the evaluation of the separation power of thirteen thin-layer chromatographic systems for splitting a methanolic extract of leaves of Helleborus atrorubens Waldst. et Kit. into 15 compounds (flavonoids and phenolic acids) have been investigated. For this purpose, the following mathematical approaches have been applied: calculation of the information content (I), determination of discriminating power (DP) and formation of clusters and dendrogram. The most suitable chromatographic system for the separation of investigated compounds is ethyl acetate-formic acid-water (65:15:20, v/v/v).