Cucurbita pepo (CP) seeds are traditionally used to alleviate lower urinary tract symptoms associated with benign prostatic hyperplasia and overactive bladder. While these effects are often attributed to lipophilic constituents, recent studies have highlighted the therapeutic potential of oil-free hydroethanolic extracts. However, their composition remains insufficiently characterized, considering the species’ significant phenotypic and phytochemical variability. This study aimed to characterize the phytochemical profile of hydrophilic hydroethanolic seed extracts from ten CP cultivars originating from different European regions, with a focus on compositional variability. The elemental composition, along with primary and secondary metabolites, was analyzed using established spectroscopic and chromatographic methods. The extracts showed considerable variation in protein (45.39 to 114.58 mg/g dw) and free amino acid content (46.51 to 111.10 mg/g dw), as well as differences in elemental composition. Principal component analysis revealed distinct clustering patterns, with several samples displaying metabolite profiles comparable to the Cucurbita pepo var. styriaca variety currently recommended by the European Pharmacopoeia (Ph. Eur.) and the Committee on Herbal Medicinal Products (HMPC). These findings open the possibility of using other CP varieties as alternative sources for extract preparation and offer novel insights into the composition of less explored hydrophilic extracts derived from CP seeds.

Zusammenfassung: Phytopharmaka sind wertvoll bei der Behandlung der akuten Bronchitis und helfen dabei, einen unangemessenen Antibiotikaeinsatz zu reduzieren. Die fixe Kombination aus Thymiankraut und Primelwurzel wirkt vermutlich synergistisch, um Symptome einer akuten Bronchitis zu bekämpfen. Die Wirksamkeit und Verträglichkeit der Kombination wurde u. a. in 2 randomisiert placebokontrollierten klinischen Studien an Erwachsenen untersucht, wo die Kombination zu einem schnelleren Ende der Bronchitissymptome führte als Placebo. Beide pharmazeutischen Zubereitungen (Lösung und Saft) zeigten eine vergleichbare Wirksamkeit.Anwendungsbeobachtungen an insgesamt mehr als 1500 Kindern zeigen, dass sich die Phytokombination auch im Alter von 1–12 Jahren durch gute Wirkung und Verträglichkeit auszeichnet. Zudem wurde eine nicht-interventionelle Studie an Säuglingen (Alter 6–12 Monate) durchgeführt. Auch in dieser Altersgruppe war die Phytokombination effektiv und sicher.

Actaea racemosa L. (syn. Cimicifuga racemosa (L.) Nutt., black cohosh) rhizomes contain triterpene glycosides (TTGs) that serve as principal quality markers in the European Pharmacopoeia (Ph. Eur.) monograph. However, discrepancies between chromatographic profiles of the plant material and the herbal reference standard (HRS) dry extract complicate quality assessment. This study elucidated the chemical origin of these discrepancies and evaluated whether the extract-based HRS can represent the analytical fingerprint of the plant material. Thirteen TTGs were identified and characterized within the official Ph. Eur. HPLC–ELSD method using centrifugal partition chromatography, semi-preparative UPLC, HRMS, GC–MS and NMR spectroscopy, employing reference standards and isolated compounds. Three malonylated TTGs (8a, 9a, 10a) were detected in wild and cultivated rhizomes but were absent from the A. racemosa dry extract HRS and other dry extracts. Quantitative analysis revealed that cultivated plants contained an insufficient amount of TTGs; however, after extraction, both the amount and the profile aligned with the Ph. Eur. requirements. This behavior is explained by the degradation and rearrangement pathways of the TTGs. Overall, these findings clarify the origin of chemical variability between plant and extract fingerprints and support the inclusion of malonylated TTGs in the quantitative determination of A. racemosa triterpene glycosides in the Ph. Eur.

Hydroethanolic Cucurbita pepo seed extracts are traditionally used for alleviating lower urinary tract symptoms (LUTS), yet their mechanisms remain unclear. Adenosine, a purine nucleoside involved in neuromodulation and smooth muscle relaxation, was recently identified in C. pepo seeds. Since A₁ adenosine receptors (A₁AR) suppress parasympathetic bladder overactivity by inhibiting acetylcholine (ACh) release, we investigated to which extent purines from pumpkin seed extracts contribute to A₁AR activation. Complementary antioxidant capacity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Three hydrophilic seed extracts containing different adenosine levels (0.60–1.18 mg/g dw) were evaluated for agonist activity using a cAMP inhibition assay. The most active extract showed an EC₅₀ of 40.22 µg/mL. Selective removal of adenosine shifted the dose–response curve rightward, while further elimination of an adenosine derivative increased the EC₅₀ to 212.10 µg/mL, confirming adenosine as the principal active compound. Guanosine and inosine did not exhibit A₁AR agonist or allosteric effects. All samples exhibited measurable but weak antioxidant activity (IC₅₀ = 1.02–4.19 mg/mL), consistent with their low total phenolic content. These findings underscore the importance of accounting for naturally occurring agonists in plant extracts to avoid overestimating receptor-mediated effects in vitro which are not translatable in vivo.