From Stem to Spectrum: Phytochemical Characterization of Five Equisetum Species and Evaluation of Their Antioxidant Potential.

The Equisetaceae family, commonly known as horsetails, has been of scientific interest for decades due to its status as one of the most ancient extant vascular plant families. Notably, the corresponding species have found their place in traditional medicine, offering a wide array of applications. This study presents a comprehensive phytochemical analysis of polar secondary metabolites within the sterile stems of five distinct Equisetum species using HPLC-DAD-ESI-MSn. For this purpose, fresh plant material was extracted with acetone/water, and the resulting crude extracts were fractionated using dichloromethane, ethyl acetate, and n-butanol, respectively. The results reveal a complex array of compounds, including hydroxycinnamic acids, hydroxybenzoic acids, flavonoids, and other phenolic compounds. In addition, total phenolic contents (Folin-Ciocalteu assay) and antioxidant activities (DPPH assay) of the plant extracts were evaluated using spectrophotometric methods. The present comparative analysis across the five species highlights both shared and species-specific metabolites, providing valuable insights into their chemical diversity and potential pharmacological properties.

Impact of Fermentation on the Phytochemical Profile and Bioactivity Characteristics of Aqueous Matricaria recutita L. Root Extracts.

While the flowers of Matricaria recutita L., German chamomile, are widely used for medicinal and cosmetic purposes, little is known about its roots, which are used in complementary medicine for the preparation of aqueous fermented extracts for the treatment of cramps and anxiety. To broaden the understanding of the active principles involved, a model fermentation approach was developed and fermentates were compared to commercially manufactured tinctures. Coumarins and hydroxycinnamates were among the major secondary metabolites characterized using HPLC-MSn. After six months of fermentation and storage, low-molecular organic acids were detected by GC-MS. Fermentation contributed to the stabilization of antioxidant and radical scavenging activities, which were in a range of about 8-10 mg gallic acid equivalents/g dry weight and 20-24 mg trolox equivalents/g dry weight, determined by Folin-Ciocalteu and DPPH assays, respectively. In addition, antibacterial activities of the extracts against Gram-positive and -negative bacteria increased during the first week of fermentation. Fermentates were neither cytotoxic nor pro- or anti-inflammatory. Thus, fermentation of chamomile roots is a suitable method for the safe production of biofunctional aqueous chamomile root extracts that remain stable without the addition of synthetic preservatives.

Phytochemical Characterization of Chamomile (Matricaria recutita L.) Roots and Evaluation of Their Antioxidant and Antibacterial Potential.

Matricaria recutita L., German chamomile, is one of the most widely used medicinal plants, whose efficacy has been proven in numerous studies. However, its roots have attracted only little interest so far, since mainly above-ground plant parts are used for medicinal purposes. To broaden the knowledge of chamomile roots, a profound phytochemical characterization was performed along with a bioactivity screening of corresponding root extracts. While volatile constituents such as chamomillol and polyynes were detected using GC-MS, HPLC-MSn analyses revealed the occurrence of four coumarin glycosides, more than ten phenolic acid esters and five glyceroglycolipids. Furthermore, the antioxidant activity of the extracts was evaluated. Polar extracts revealed IC50 values ranging from 13 to 57 µg/mL in the DPPH radical scavenging assay, which is in the same range as reported for chamomile flower extracts. In addition, superoxide radical scavenging potential and mild antibacterial effects against S. aureus und B. subtilis were demonstrated. Moreover, to assess interspecies variation in chamomile roots, extracts of M. recutita were compared to those of M. discoidea DC. Interestingly, the latter revealed stronger antioxidant activity. The presented results aim at the valorization of chamomile roots, previously discarded as by-product of chamomile flower production, as a sustainable source of bioactive phytochemicals.

Evaluation of Geum urbanum L. Extracts with Respect to Their Antimicrobial Potential.

Preparations derived from roots and rhizomes of Geum urbanum L. are traditionally used for the treatment of ulcers and irritations of mucous membranes of the mouth, stomach, and intestinal tract. In complementary medicine, fermentation is one of the methods applied to recover plant extracts used for the production of such pharmaceutical preparations. The present study was performed to characterize the secondary metabolites and to evaluate the antimicrobial potential of different G. urbanum root and rhizome extracts. For this purpose, individual metabolites of fresh and fermented G. urbanum root and rhizome extracts were analyzed by HPLC-DAD-MSn and GC/MS. Among others, rare ellagitannin-sulfates could be characterized by LC/MSn . In addition, the antibacterial activity of various extracts of fresh and dried G. urbanum roots and rhizomes against Staphylococcus aureus (ATCC 6538) and Cutibacterium acnes (CP033842.1; FDAARGOS 503 chromosome) were assessed and compared to that of G. rivale. Furthermore, low- and high-molecular tannins were fractionated by column chromatography, demonstrating the latter to exhibit highest antibacterial activity.