Flavonoids are a large group of polyphenolic secondary metabolites of plants with high biologically active properties. Their determination in plant extracts (medicinal, edible, and other plants, as well as products made from them) with a complex chemical composition is a difficult task and requires effective separation of the components. In this study, a new approach to the determination of 18 flavonoids in plant extracts using reversed-phase comprehensive two-dimensional liquid chromatography with UV detection (LC×LC-UV) is proposed. The approach has been successfully tested on various plant raw materials: above-ground parts of bog rosemary, bog bilberry, bilberry, lingonberry, and cranberry, as well as aspen and apricot knots. It was found that aspen knots are a rich source of aromadendrin and naringenin and their derivatives, while apricot knots are a rich source of catechin and epicatechin, and bog rosemary is a rich source of quercetin glycosides-hyperoside, reinoutrin, and avicularin. The approach for isolation of pure hyperoside, reinoutrin, and avicularin from bog rosemary extract by preparative HPLC was proposed. Other phenolic compounds of the studied plant extracts were classified (by LC×LC-MS/MS) as hydroxycinnamic acid derivatives, iridoids, and flavonoids. The developed approaches are promising for bioprospecting of flavonoids and phenolic compounds in various plant materials. It can also be used for quality control of medicinal, edible, and other plants, as well as products made from them.

Periodontitis is a chronic inflammatory disease driven by dysbiosis of the subgingival microbiota, leading to immune dysregulation and progressive alveolar bone loss. In recent years, immunotherapeutic approaches, particularly those involving natural products, have gained attention as potential adjuvants to conventional therapy. This study evaluated the effects of four alkaloids, boldine, laurolitsine, laurotetanine, and N-methyl-laurotetanine, on alveolar bone loss and local immune regulation in experimental periodontitis.Male and female C57BL/6 mice with ligature-induced periodontitis received daily oral administration of each alkaloid (20 mg/kg) for 10 days. Alveolar bone loss was quantified by micro-computed tomography (micro-CT). Periodontal immune responses were assessed by RT-qPCR analysis of pro-inflammatory cytokines, T-cell-related transcription factors, and bone metabolism mediators (RANKL and OPG). In addition, regulatory T (Treg) cells in cervical lymph nodes were analyzed by flow cytometry.Boldine and laurolitsine significantly reduced alveolar bone loss compared with untreated periodontitis, in parallel with decreased RANKL expression. All four alkaloids significantly reduced IL-6 expression, with laurolitsine additionally suppressing IL-17A expression in periodontal tissues, whereas N-methyl-laurotetanine reduced IL-10 expression. No significant changes were observed in CD4+, CD4+FoxP3+, and CD4+FoxP3+CD25+ T-cell frequencies between treated and untreated groups.Oral administration of boldine and laurolitsine attenuates periodontitis-associated alveolar bone loss, likely through differential modulation of cytokine networks and osteoclastogenic signaling. These findings support their potential as host-modulating agents in the management of periodontitis.

Kynurenine (KYN) is a non-protein amino acid and major metabolite of tryptophan associated with human health. The acidic form, kynurenic acid (KYNA), has been previously identified in St.John's wort (SJW) tablets and tea, but other metabolites in the pathway are not known in the species. We developed and validated two liquid chromatography-mass spectrometry-based (UHPLC-Orbitrap MS) methods for the quantification of KYNA, KYN, 3-hydroxykynurenine (3-HK), and 3-hydroxyanthranilic acid (3-HAA). We compared two approaches: (1) derivatisation via 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) and (2) analysis of underivatised extracts. KYN was detected in both methods (78% and 101% recovery in underivatised and derivatised, respectively), and 3-HAA was detected only by the underivatised method (95%), while 3-HK was detected only by the derivatised method (90%). Methods were validated for key parameters, including linearity, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). Three of the KYN metabolites were detected in in vitro-grown SJW shoots: KYN (101 ng/g), KYNA (104 ng/g), and 3-HAA (670 ng/g). Significantly more KYN and KYNA was detected in greenhouse-grown plants than in tissue-cultured SJW. KYN, KYNA, and 3-HAA were also quantified in commercial preparations of SJW at 0.07 - 0.42 µg/g (KYN), 2.31 - 6.45 µg/g (KYNA), and 0.86 - 3.54 µg/g (3-HAA); 3-HK was not detected in any of our SJW samples. These data support future studies to understand the role of kynurenine metabolites in plant metabolism and plant-based products.

Glycyrrhizae Radix (GR), the dried root and stolon of Glycyrrhiza uralensis or G. glabra, is most frequently used as a crude drug, compounding Kampo medicines to treat a variety of diseases in Japan. This key crude drug, however, would be coinstantaneously a risk factor for pseudoaldosteronism. This adverse effect is thought to be due to glycyrrhetinic acid (GA), a major metabolite of glycyrrhizin, which is one of the ingredients of GR. Therefore, we thought that if the blood GA concentration could be measured quickly and easily when side effects occur, the causal relationship could be clarified, and side effects could be avoided. To realize this plan, we developed the competitive ELISA using anti-GA monoclonal antibody (mAb6D6), which was labeled 'biotin' to avoid endogenous effects, such as antibodies in serum, and to detect GA sensitively. This ELISA could quantify GA from about 10 pg/mL to 25 ng/mL. The quantitative value of GA in serum based on this ELISA was significantly corelated with that of GA based on high-performance liquid chromatography. Hence, the developed competitive ELISA could be an useful tool for users who would like to quantify the blood GA concentration to clarify the relationship between GA and pseudoaldosteronism derived from the intake of medicines containing GR and to lead to avoiding side effects derived from GA.

Plants have been a central source of natural resources for humanity with all kinds of uses and applications: food, cosmetics, natural remedies and medicines, dyes, textiles, construction materials, ornamental uses, and the extraction of various compounds, including natural pigments. Within pigments, there are four major groups of interest: anthocyanins, chlorophylls, betalains, and carotenoids. Carotenoids are characterized by being formed by relatively long hydrocarbon chains (25 - 50 C), which can end in linear or cyclic structures. In the carotenoid group, bixin and norbixin are two compounds of undeniable relevance as food and cosmetic pigments. However, in recent years, these compounds have been studied to understand other possible effects, mainly in the field of health, yielding promising results. This review features results from studies published in recent years with a focus on possible applications in the field of public health, mainly related to metabolic problems such as sugar and fat metabolism. Additionally, various other health applications are analyzed, and the results are summarized. The main conclusions reached by the authors are also mentioned for a better understanding of the importance of each study. Finally, general conclusions and perspectives are provided in order to continue exploring the possible applications of bixin and norbixin as potential bioactive and functional compounds.

The Solanaceae family comprises numerous species of economic and pharmacological importance, including the toxic deadly nightshade (Atropa belladonna), bittersweet nightshade (Solanum dulcamara), and black nightshade (Solanum nigrum). These plants are native to Europe, North Africa, and Western Asia, and have been used since ancient times in both ritual practices and medicine. A.belladonna contains potent tropane alkaloids (atropine, hyoscyamine, and scopolamine) and is widely utilized in modern pharmacology, although accidental poisonings still occur, often due to confusion with edible plants or the misuse of herbal and homeopathic preparations. In contrast, S. dulcamara contains glycoalkaloids such as solanine, solasodine, and β-solamarine, while S. nigrum contains solanine, solamargine, and solasonine. Both species have a history of traditional use as narcotics, diuretics, and treatments for skin, rheumatic, and respiratory conditions, as well as for pain, inflammation, fever, and other disorders; however, they also pose significant toxicological risks to humans and animals. Although poisonings from these two species are less common than those caused by A.belladonna, they still occur. A review of the literature identified 41 studies reporting poisoning cases associated with these plants, primarily resulting from berry ingestion. Poisoning typically produces anticholinergic syndrome, underscoring the importance of accurate identification and prompt treatment.

Citral-rich essential oils (CEO) exhibit remarkable antioxidant potential. In this review, we discuss chemical and biological aspects of citral and CEO, estimating possible mechanisms of action. To this end, a literature search was carried out in the Scielo, PubMed, and Google Scholar databases, focusing on the antioxidant potential of CEO. Analyzed studies demonstrated the protective capacity of citral and CEO in cells stressed by hydrogen peroxide and excess glucose in the medium. Moreover, citral has antimicrobial, anti-inflammatory, and antimutagenic activity that can be exploited in a cell culture. The antioxidant activity of citral is attributed to the presence of an aldehyde group and multiple unsaturations in its structure, which enable it to scavenge free radicals and convert them into auto-oxidizing epoxides that are rapidly eliminated by the cell. Citral epigenetically modulates DNA, increasing the activity of endogenous antioxidant enzymes, while inhibiting enzymes involved in lipid peroxidation. In parallel, CEO and citral contribute to maintaining DNA integrity through kinase-related signaling pathways. Despite growing evidence of their antioxidant potential, studies investigating the bioactivity of citral and CEOs in animal cell cultures remain limited. Furthermore, research exploring the synergistic activity of citral with other compounds is still scarce, despite their significant scientific relevance. This scenario reinforces the need for further investigations to elucidate their mechanisms of action and to establish reference parameters guiding their application in different cellular and reproductive models in vitro.

Herbal preparations of senna leaves or fruits are commonly used as laxatives. The European Medicines Agency (EMA) sets a daily dose of 10-30 mg for the hydroxyanthracene glycosides (HAG) determined by spectrophotometry. A recent revision of the European Pharmacopoeia monographs on senna replaced the photometric assay with HPLC. The new method offers improved reproducibility and specificity but results in lower content, while the dose recommendation in the EMA monograph still refers to the photometric determination. The systematic difference between the photometric and the HPLC method has been studied in a collaborative inter-laboratory trial by seven participating quality control laboratories. The goal was to compare precision and reproducibility and ideally to derive a conversion factor. The HAG determination by spectrophotometry according to the method from Ph. Eur. Edition 8.3. was compared to the HPLC assay according to the new method for senna leaves or pods (Ph. Eur. Ed. 10.1). The photometric method showed a low inter-laboratory reproducibility of about ± 28% (RSD) but an intra-laboratory precision of around 2%, while the HPLC method showed an inter-laboratory precision of around ± 10% and an intra-laboratory precision of 1.5%. Assay values obtained by HPLC were about 90% of the values of the photometric method, but this relation seems to be sample dependent. Because of its dependency on the raw material, a simple conversion factor between the two methods is not yet satisfying but an additional method-specific dose recommendation for the EMA monographs is proposed by the authors.

Mesembryanthemum tortuosum is a succulent plant native to southern Africa and was traditionally used to enhance mood. Recent research into M.tortuosum's mood-enhancing effects has culminated in the development of a standardised extract, Zembrin, containing consistent levels of mesembrine alkaloids considered to be the main bioactive compounds. This review aims to critically investigate published in vivo animal and clinical studies using M.tortuosum, Zembrin, and mesembrine alkaloids, to evaluate the study designs, formulations, and dosages used, and to assess the results in terms of safety and therapeutic efficacy as an antidepressant and anxiolytic. Four databases, namely PubMed, Scopus, Web of Science, and ScienceDirect, were searched using terms relating to 'clinical trials', 'in vivo', 'Mesembryanthemum', 'M.tortuosum', 'pre-clinical', 'Sceletium', 'S. tortuosum', and 'Zembrin'. The search was conducted to identify original research articles published before July 2025. Although published pre-clinical animal and clinical studies on M.tortuosum-derived products offer valuable insights, such as a favourable safety profile and potential efficacy as an anxiolytic and antidepressant, several limitations have been identified, including small sample sizes and studies conducted in clinically irrelevant populations. A limited number of reported outcomes suggest that Zembrin may have positive effects on anxiety, cognitive function, stress resilience, and mood. However, not all studies showed consistent benefits, and some outcomes were limited to specific measures such as EEG changes or reaction time under cognitive stress. Large-scale clinical trials in relevant populations should be conducted to determine the potential of M.tortuosum-derived products as anxiolytics and antidepressants.