Without being aware of their chemical composition, many cultures have used herbaceous peony roots for medicinal purposes. Modern phytopreparations intended for use in human therapy require specific knowledge about the chemistry of peony roots and their biological activities. In this study, ethanol-water extracts were prepared by maceration and microwave- and ultrasound-assisted extractions (MAE and UAE, respectively) in order to obtain bioactive molecules from the roots of Paeonia tenuifolia L., Paeonia peregrina Mill., and Paeonia officinalis L. wild growing in Serbia. Chemical characterization; polyphenol and flavonoid content; antioxidant, multianti-enzymatic, and antibacterial activities of extracts; and in vitro gastrointestinal digestion (GID) of hot water extracts were performed. The strongest anti-cholinesterase activity was observed in PT extracts. The highest anti-ABTS (2,2\'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical potential was observed in PP extracts, whereas against DPPH (2,2-diphenyl-1-picrylhydrazyl radicals), the best results were achieved with PO extracts. Regarding antibacterial activity, extracts were strongly potent against Bacillus cereus. A molecular docking simulation was conducted to gather insights into the binding affinity and interactions of polyphenols and other Paeonia-specific molecules in the active sites of tested enzymes. In vitro GID of Paeonia teas showed a different recovery and behavior of the individual bioactives, with an increased recovery of methyl gallate and digallate and a decreased recovery of paeoniflorin and its derivatives. PT (Gulenovci) and PP (Pirot) extracts obtained by UAE and M were more efficient in the majority of the bioactivity assays. This study represents an initial step toward the possible application of Paeonia root extracts in pharmacy, medicine, and food technologies.

Swertia perennis Linnaeus (SP) has been utilised to treat gastritis. We report the qualitative and quantitative phytochemical analysis, antioxidant and enzyme inhibitory activities of SP. The correlation between the biological activities and total bioactive contents of the extracts was also studied via multivariate analysis. Methanol extract contained many active compounds and exhibited good antioxidant activity. Therefore, this was selected for further phytochemical profiling and stability studies. Fourteen compounds were identified by ultra-performance liquid chromatography-electrospray ionisation-orbitrap-mass spectrometry for the first time from this plant. Iridoids, xanthones, and flavonoids were the main components. Methanol extract exhibited good stability and antioxidant capacity in stability studies, with low toxicity, and showed a protective effect on the oxidation of olive and sunflower oils. SP has the potential to be developed and used as an antioxidant, or as urease and XO inhibitors, and its methanol extract could be used as a natural oil stabiliser.

To develop the medicinal and edible plant resources of Althaea officinalis Linn in Europe and other places, this study concentrated on the bioactive ingredients of its different extracts. The phytochemical compositions of MeOH extracts were evaluated by UPLC-DAD-ESI-Q-TOF-MSn analysis. The in vitro antioxidant properties, enzymes inhibitory effects and nitric oxide (NO) production inhibitory activities of fractions obtained from the aerial parts of Althaea officinalis (APAO) were evaluated. The results identified 76 compounds, including 8 phenolic acids, 17 flavonoids, 6 coumarins, 9 triterpenes and 11 alkaloids. Fr. C-2 of APAO was found to have the highest TPC (175.8 ± 1.5 mg GAE/g) and TFC (466.9 ± 5.0 mg RE/g) with the highest antioxidant capacity in DPPH, ABTS, CUPRAC, FRAP and β-carotene bleaching assays. Fr. A showed noticeable inhibition of α-glucosidase with an IC50 value of 3.8 ± 0.1 μg/mL. However, Fr. B displayed stronger inhibitory activity on 5-lipoxygenase than quercetin, with the IC50 value of 8.4 ± 1.6 μg/mL. In addition, Fr. B also possessed potent inhibitory activities on NO production toward LPS-activated RAW 264.7 Cells with an IC50 value of 15.7 ± 1.6 μg/mL. Our findings suggest that different Althaea officinalis extracts may be considered sources of phenolic and flavonoid compounds with high potential as natural antioxidants, anti-inflammatory agents and blood sugar regulators. In addition, they can also be used in food and nutraceutical products with enhanced bioactivities.

This study investigated the content and biological activity of three solvent extracts of Adonis ramosa Franch (AR), which contains 12 types of phytochemicals. The overall yield and total protein content of the aqueous extract were the highest, and it exhibited the highest hydroxyl and superoxide radical-scavenging abilities, copper chelating abilities, and cupric reducing antioxidant capacity. Ethanol extract had the highest total phenolic, flavonoid, and carbohydrate contents, and it showed the highest iron chelating activity, and HClO- and nitrite-scavenging abilities. Methanol AR extract contained the highest total steroid and tannin contents; it also demonstrated high radical- and reactive oxygen species-scavenging abilities and had the best ferric reducing antioxidant power, which allowed it to effectively prevent β-carotene bleaching. Methanol extract also showed good stability and low toxicity. All tested solvent extracts of AR exhibited weak enzyme-inhibitory activities for four enzymes (α-glucosidase, α-amylase, acetylcholinesterase and butyrylcholinesterase). Overall, AR can serve as a natural antioxidant.

The peculiarities of the survival and adaptation of deep-sea organisms raise interest in the study of their metabolites as promising drugs. In this work, the hemolytic, cytotoxic, antimicrobial, and enzyme-inhibitory activities of tentacle extracts from five species of sea anemones (Cnidaria, orders Actiniaria and Corallimorpharia) collected near the Kuril and Commander Islands of the Far East of Russia were evaluated for the first time. The extracts of Liponema brevicorne and Actinostola callosa demonstrated maximal hemolytic activity, while high cytotoxic activity against murine splenocytes and Ehrlich carcinoma cells was found in the extract of Actinostola faeculenta. The extracts of Corallimorphus cf. pilatus demonstrated the greatest activity against Ehrlich carcinoma cells but were not toxic to mouse spleen cells. Sea anemones C. cf. pilatus and Stomphia coccinea are promising sources of antimicrobial and antifungal compounds, being active against Gram-positive bacteria Bacillus subtilis, Staphylococcus aureus, and yeast Candida albicans. Moreover, all sea anemones contain α-galactosidase inhibitors. Peptide mass fingerprinting of L. brevicorne and C. cf. pilatus extracts provided a wide range of peptides, predominantly with molecular masses of 4000-5900 Da, which may belong to a known or new structural class of toxins. The obtained data allow concluding that deep-sea anemones are a promising source of compounds for drug discovery.

Peppermint is widely used medicinal plant with distinguished bioactive potential, therefore, the aim of present work was to develop novel peppermint extracts with high activity by application of traditional and emerging separation techniques. Conventional hydrodistillation and microwave-assisted hydrodistillation (MWHD) were applied for recovery of essential oil (EO), while organic solvent extraction using Soxhlet apparatus, microwave-assisted and ultrasound-assisted process and supercritical fluid extraction (SFE) were applied for non-selective recovery of peppermint lipophilic extracts. Extracts were characterized in terms of terpenoids profile with special emphasis on content of major compounds (mentol, menthone, isomenthol and eucalyptol). Antioxidant activity (DPPH, ABTS, CUPRAC, FRAP, chelating and phosphomolybdenum assay) and enzyme-inhibitory assays (acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase and glucosidase inhibition) were used for screening of peppermint bioactivity. MWHD was recognized as alternative for traditional process in EO recovery, while SFE extracts were useful for green production of solvent-free peppermint extracts rich in terpenoids and other lipophilic bioactives.

In the last decades, marine natural products (MNPs), have attracted extensive interest from both chemists and pharmacologists due to their chemical and bioactive diversities. This special issue, collecting total synthesis and structural modification of six different type of bioactive MNPs, is expected to inspire and attract more research effects invested into MNP research.