Antifungal, Antitumoral and Antioxidant Potential of the Danube Delta Nymphaea alba Extracts

Biological activities, identification, method development, and validation for analysis of polyphenolic compounds in Nymphaea rubra flowers and leaves by UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS

INTRODUCTION

Nymphaea rubra belongs to the Nymphaea family and is regarded as a vegetable used in traditional medicine to cure several ailments. These species are rich in phenolic acid, flavonoids, and hydrolysable tannin.

OBJECTIVE

This study aimed to assess the biological activities of Nymphaea rubra flowers (NRF) and leaves (NRL) by identifying and quantifying their polyphenolic compounds using ultra-performance liquid chromatography coupled to quadrupole cyclic ion mobility time-of-flight mass spectrometry (UHPLC-Q-cIM-TOF-MS) and triple quadrupole mass spectrometry (UHPLC-TQ-MS).

METHODOLOGY

NRF and NRL powder was extracted with methanol and fractionated using hexane, ethylacetate, and water. Antioxidant and α-glucosidase, and tyrosinase enzyme inhibitory activities were evaluated. The polyphenolic components of NRF and NRL were identified and quantified using UHPLC-Q-cIM-TOF-MS and UHPLC-TQ-MS. The method was validated using linearity, precision, accuracy, limit of detection (LOD), and lower limit of quantification (LLOQ).

RESULTS

Bioactive substances and antioxidants were highest in the ethylacetate fraction of flowers and leaves. Principal component analysis showed how solvent and plant components affect N. rubra's bioactivity and bioactive compound extraction. A total of 67 compounds were identified, and among them 21 significant polyphenols were quantified. Each calibration curve had R2 > 0.998. The LOD and LLOQ varied from 0.007 to 0.09 μg/mL and from 0.01 to 0.1 μg/mL, respectively. NRF contained a significant amount of gallic acid (10.1 mg/g), while NRL contained abundant pentagalloylglucose (2.8 mg/g).

CONCLUSION

The developed method is simple, rapid, and selective for the identification and quantification of bioactive molecules. These findings provide a scientific basis for N. rubra's well-documented biological effects.

In Vitro Screening of Ecotoxic and Cytotoxic Activities of Ailanthus altissima Leaf Extract against Target and Non-Target Plant and Animal Cells

Ailanthus altissima, an invasive plant species, exhibits pharmacological properties, but also some allergic effects on humans. This study aimed to evaluate the potential toxicity of A. altissima leaves, using a complex approach towards different organisms. The ecotoxic impact of a crude extract was investigated on seeds germination and brine shrimp lethality. Cytotoxicity was studied in vitro using non-target (haemolysis, liposomal model, fibroblast), and target (cancer cells) assays. Leaf extract at 1000 µg/mL significantly inhibited wheat and tomato germination, while no significant effects were found on parsley germination. A slight stimulatory effect on wheat and tomato germination was found at 125 µg/mL. In a brine shrimp-test, the extract showed a low toxicity at 24 h post-exposure (LC50 = 951.04 ± 28.26 μg/mL), the toxic effects increasing with the exposure time and extract concentration. Leaf extract caused low hematotoxicity. The extract was biocompatible with human gingival fibroblasts. No anti-proliferative effect was found within the concentration range of 10-500 µg/mL on malignant melanoma (MeWo) and hepatocellular carcinoma (HepG2). In a liposomal model-test, the extract proved to possess low capability to alter the eukaryotic cell-mimicking membranes within the tested concentration range. Given the low to moderate toxicity on tested organisms/cells, the A. altissima autumn leaves may find useful applications.

Chemical Composition and Biological Properties of New Romanian Lavandula Species

The aims of the present study were to evaluate for the first time the chemical composition and antioxidant, antibacterial, antifungal and antiproliferative potentials of the Romanian George 90 lavender species, as well as parental species, L. angustifolia and L. latifolia. The L. angustifolia, L. latifolia and George 90 essential oils were analyzed by GC-MS/MS and the L. angustifolia, L. latifolia and George 90 hydroalcoholic extracts were analyzed by HPLC-DAD. The antioxidant, antibacterial, antifungal and antiproliferative assays revealed that all the investigated species showed significant activities. The results highlighted the chemical composition and the promising biological potentials of the L. angustifolia, L. latifolia and George 90 lavender species, validating their ethnomedicinal value, which offers potential applications as natural drugs.

Polyphenol Analysis via LC-MS-ESI and Potent Antioxidant, Anti-Inflammatory, and Antimicrobial Activities of Jatropha multifida L. Extracts Used in Benin Pharmacopoeia

Jatropha multifida L., a plant from the Euphorbiaceae family, is commonly used in Benin's traditional medicine due to its therapeutic benefits. This study aims to explore the medicinal efficacy of Jatropha multifida L. by evaluating its various biological activities. An initial phytochemical analysis was conducted, following which the polyphenols and flavonoids were quantified and identified using LC-MS-ESI. The antimicrobial efficacy of the extracts was tested using agar diffusion. Their antioxidant capacity was assessed using several methods: DPPH radical reduction, ABTS radical cation reduction, ferric ion (FRAP) reduction, and lipid peroxidation (LPO). Anti-inflammatory activity was determined based on the inhibition of protein (specifically albumin) denaturation. The study identified several phenolic and flavonoid compounds, including 2-Hydroxybenzoic acid, o-Coumaroylquinic acid, Apigenin-apiosyl-glucoside, and luteolin-galactoside. Notably, the extracts of J. multifida demonstrated bactericidal effects against a range of pathogens, with Concentration Minimally Bactericidal (CMB) values ranging from 22.67 mg/mL (for organisms such as S. aureus and C. albicans) to 47.61 mg/mL (for E. coli). Among the extracts, the ethanolic variant displayed the most potent DPPH radical scavenging activity, with an IC50 value of 0.72 ± 0.03 mg/mL. In contrast, the methanolic extract was superior in ferric ion reduction, registering 46.23 ± 1.10 µgEAA/g. Interestingly, the water-ethanolic extract surpassed others in the ABTS reduction method with a score of 0.49 ± 0.11 mol ET/g and also showcased the highest albumin denaturation inhibition rate of 97.31 ± 0.35% at a concentration of 1000 µg/mL. In conclusion, the extracts of Jatropha multifida L. are enriched with bioactive compounds that exhibit significant biological activities, underscoring their therapeutic potential.

Ethnopharmacological Value and Biological Activities via Antioxidant and Anti-Protein Denaturation Activity of Morinda lucida Benth and Momordica charantia L. Leaves Extracts from Benin

Momordica charantia Linn. (Cucurbitaceae), the wild variety of bitter melon, and Morinda lucida Benth (Rubiaceae) were commonly used as a popular folk medicine in Benin. This study aimed to appreciate the ethnopharmacological knowledge and evaluate the antioxidant and anti-inflammatory effects of M. charantia and M. lucida leaves extracts. Semi-structured surveys supported by individual interviews were conducted with herbalists and traditional healers in southern Benin. The antioxidant activities were evaluated by a micro-dilution technique using ABTS and FRAP methods. These activities were supported by cyclic voltammetry analysis. The anti-inflammatory activity was evaluated by the albumin denaturation method. The volatile compounds were analysed by GC-MS analysis. All the respondents involved in this study have good knowledge of the two plants. We identify 21 diseases grouped into five categories of condition. The two plants' extracts possess variable antioxidant capacity. Indeed, all the active extracts of M. charantia presented an IC₅₀ < 0.078 mg/mL, while the extracts of M. lucida had an IC₅₀ up to 0.21 ± 0.02 mg/mL. For anti-inflammatory activity, a dose-response activity (p < 0.001) was observed in the protein denaturation inhibition rate of the extracts. It should be noted that the highest inhibition rate (98.34 ± 0.12) of the albumin denaturation was observed with M. lucida dichloromethane extract. A total of 59 volatile compounds were identified by GC-MS analysis in the extracts of the two plants. The M. charantia ethyl acetate extract shows the presence of 30 different compounds with a relative abundance of 98.83%, while that of M. lucida shows 24 compounds with a relative abundance of 98.30%. These plants are potential candidates to discover new compounds with therapeutic properties that could be used to solve public health problems.

Bridging the Chemical Profile and Biological Activities of a New Variety of Agastache foeniculum (Pursh) Kuntze Extracts and Essential Oil

This study investigated the phytochemical content of alcoholic extracts and essential oil of a new variety of medicinal plants, Agastache foeniculum (Pursh), which Kuntze adapted for cultivation in Romania, namely “Aromat de Buzău”. The essential oil was investigated by GC-MS, while the identification and quantification of various compounds from alcoholic extracts were performed by HPLC-DAD. The total phenol and flavonoid contents of the extracts were evaluated by using standard phytochemical methods. The antioxidant activities of ethanol, methanol extracts, and essential oil of the plant were also assessed against 2,2′-diphenyl-1-picrylhydrazyl (DPPH•), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), and by ferric reducing power (FRAP) using spectroscopic methods. Cyclic voltammetry was used to evaluate the antioxidant capacity of the essential oil. The concentrations of phenolic compounds were higher in methanolic extract compared to ethanolic extract. A significant correlation was found between total phenol and total flavonoid contents (r = 0.9087). Significant high correlations were also found between the total phenolic compounds and the antioxidant activities of the extracts (r ≥ 0.8600, p < 0.05). In addition, the extracts and essential oil showed good antioxidant and xanthine oxidase inhibitory activities. Estragole was detected as the major constituent of the essential oil (94.89%). The cytotoxic activity of the essential oil was evaluated by the MTT assay. At lower concentrations (1 µg/mL) high cytotoxicity against MCF-7 breast cancer cells was observed but not on the non-tumoral dermal fibroblasts (HDF) which indicated selectivity for cancer cells and suggests the presence of biologically active components that contribute to the observed high cytotoxic effect. Findings from the present study offer new perspectives on the use of A. foeniculum as a potential source of bioactive compounds and a good candidate for pharmaceutical plant-based products.

Characterizations of Six Pomegranate (Punica granatum L.) Varieties of Global Commercial Interest in Morocco: Pomological, Organoleptic, Chemical and Biochemical Studies

Pomegranate variety properties are important not only to demonstrate their diversity but also to satisfy the current market need for high-quality fruits. This study aims to characterize pomological and physico-chemical features as well as the antioxidant capacity of Moroccan local cultivars (Djeibi, Mersi, Sefri 1 and Sefri 2) compared to the imported ones (Mollar de Elche and Hicaz). The pomological characteristics of varieties were relatively diverse. The juice varieties (PJ) displayed a marketed variability in organoleptic and quality properties, such as the flavor, juice yield, and micro/macronutrients contents. Interrelationships among the analyzed properties and PJ varieties were investigated by principal component analysis (PCA). Dimension of the data set was reduced to two components by PCA accounting for 64.53% of the variability observed. The rinds varieties (PR) were studied for their total phenolics, flavonoids, and condensed tannins quantifications. PR varieties extracts exhibited different levels of free radical scavenging activity and local varieties revealed a greater potential with stability over time. The HPLC-DAD analyses of PR extracts revealed (+) catechin as the major compound, where the highest content was found for the local varieties. The SEC analysis showed the molecular weight distribution of phenolic compounds with a high size of condensed tannins formed by the polymerization of the catechin monomer. Given these properties, this research provides an easy selection of high-quality fruits as potential candidates for local market needs.

Allantoin from Valuable Romanian Animal and Plant Sources with Promising Anti-Inflammatory Activity as a Nutricosmetic Ingredient

Helix aspersa (HA), Helix pomatia (HP) and Symphytum officinale are common organisms in Romania’s biosphere, widely known for their allantoin content and their therapeutic properties. Herein, the allantoin was separated and quantified from the aqueous extracts of Romanian comfrey root and the secretions of HA and HP snails. This study also focused on determining the antioxidant and anti-inflammatory activities of these Romanian allantoin-rich samples. The plant extracts were obtained through two methods: ultrasonic extraction and enzymatic ultrasonic extraction. A microplate method was used for the quantitative determination of allantoin content. The antioxidant activity was measured by using the DPPH radical scavenging method. The antioxidant capacity of the samples was studied in order to observe the type of interactions generated by the chemical complex present in their composition. High concentrations of allantoin were obtained by enzymatic ultrasonic extraction method (EUE—102 ± 0.74 μg/mL), and also in the water-soluble fraction of the snail secretion (FS1—22.051 μg/mL). The antioxidant screening suggests that Symphytum officinale and snail mucus extracts could be used as promising natural substitutes for synthetic antioxidants in products used for therapeutic purposes. The evaluation of anti-inflammatory activity was also investigated, allantoin-rich samples showing a promising action (FS1—81.87 ± 2.34%). In future, the inclusion of allantoin-rich extracts in various novel pharmaceutical forms for new therapeutic applications could be achieved. The study will continue with the formulation of a nutricosmetic product with snail mucus and Symphytum officinale extract as principal bioactive ingredients.

Sono-Biosynthesis and Characterization of AuNPs from Danube Delta Nymphaea alba Root Extracts and Their Biological Properties

Root extracts from Danube Delta Nymphaea alba were used to prepare gold nanoparticles (AuNPRn) by reducing HAuCl4 at different pHs (6.4-8.4) using ultrasonic irradiation: an easy, cheap, eco-friendly and green approach. Their antibacterial and anticancer activities were evaluated against Staphylococcus aureus and Escherichia coli, and A2780 ovarian cancer cells, respectively. The AuNPRn were characterized concerning their phytoconstituents (polyphenols, flavonoids and condensed tannins) and gold content. All of the nanoparticles were negatively charged. AuNPRn exhibited a hydrodynamic size distribution ranging from 32 nm to 280 nm, with the larger nanoparticles being obtained with an Au/root extract ratio of 0.56, pH 7 and 10 min of sonication (AuNPR1), whereas the smallest were obtained with an Au/root extract ratio of 0.24, pH 7.8 and 40 min of sonication (AuNPR4). The TEM/SEM images showed that the AuNPRn had different shapes. The ATR-FTIR indicated that AuNPRn interact mainly with hydroxyl groups present in the polyphenol compounds, which also confirm their high antioxidant capacity, except for AuNPR2 obtained at pH 6.4. Among the AuNPRn, the smallest ones exhibited enhanced antimicrobial and anticancer activities.

High Resolution Mass Spectroscopy-Based Secondary Metabolite Profiling of Nymphaea nouchali (Burm. f) Stem Attenuates Oxidative Stress via Regulation of MAPK/Nrf2/HO-1/ROS Pathway

The secondary metabolites profiling of Nymphaea nouchali stem (NNSE) extract was carried out using a high-resolution mass spectroscopic technique. The antioxidant effects of NNSE, as well as the underlying mechanisms, were also investigated in tert-butyl hydroperoxide (t-BHP)-stimulated oxidative stress in RAW264.7 cells. Tandem mass spectroscopy with (-) negative mode tentatively revealed the presence of 54 secondary metabolites in NNSE. Among them, phenolic acids and flavonoids were predominant. Phenolic acids (brevifolincarboxylic acid, p-coumaroyltartaric acid, niazinin B, lalioside, 3-feruloylquinic acid, and gallic acid-O-rutinoside), flavonoids (elephantorrhizol, apigenin-6-C-galactoside 8-C-arabinoside, and vicenin-2), sialic acid (2-deoxy-2,3-dehydro-N-acetylneuraminic acid), and terpenoid (α-γ-onoceradienedione) were identified in NNSE for the first time. Unbridled reactive oxygen species/nitrogen species (ROS/RNS) and redox imbalances participate in the induction and development of many oxidative stress-linked diseases. The NNSE exhibited significant free radical scavenging capabilities and was also able to reduce t-BHP-induced cellular generation in RAW264.7 cells. The NNSE prevented oxidative stress by inducing the endogenous antioxidant system and the levels of heme oxygenase-1 (HO-1) by upregulating Nrf2 through the modulation of mitogen-activated protein kinases (MAPK), such as phosphorylated p38 and c-Jun N terminal kinase. Collectively, these results indicate that the NNSE exhibits potent effects in preventing oxidative stress-stimulated diseases and disorders through the modulation of the MAPK/Nrf2/HO-1 signaling pathway. Our findings provide new insights into the cytoprotective effects and mechanisms of Nymphaea nouchali stem extract against oxidative stress, which may be a useful remedy for oxidative stress-induced disorders.

Flavonoid Profiles of Two New Approved Romanian Ocimum Hybrids

Basil (Ocimum spp.) is a traditional herbal medicine abundant in antioxidants such as phenolic compounds. As part of a diet, this herb is proved to have some roles in decreasing the risk of cancer, and in the treatment of inflammation and neurodegenerative diseases. This study aims to explore the total phenolic and flavonoid content of two new basil hybrids growing in Romania, namely "Aromat de Buzau" (AB) and "Macedon" (MB). The antioxidant capacity of those two species was also analyzed by DPPH and cyclic voltammetry. Six different flavonoids, such as catechin (+), rutin, hyperoside, naringin, naringenin, and genistein, were separated, identified, and quantified by HPLC-DAD chromatography, for the first time, from romanian basil hybrids. The main flavonoid of the extracts was found to be naringin which is present in the highest amount (26.18 mg/kg) in "Aromat de Buzau" (O. basilicum) methanolic extract. These results suggest that dietary intake of these new hybrids can be a source of antioxidant compounds.

New Insights into Antibacterial Compounds: From Synthesis and Discovery to Molecular Mechanisms of Action

The worldwide emergence of microbial resistance to available antibiotics presents a global threat to public health and health systems. This special issue aimed to gather papers describing novel antibiotics, originating form chemical synthesis, repurposing of existent drugs, or from natural sources like plant extracts, herbs and spices. A total of 13 papers were published, covering a wide range of topic, including antimicrobial resistance surveillance studies; synthesis of novel molecules with antimicrobial activities; modification or repurposing of already existing molecules, plant-derived active extracts, and molecules; the effects of antimicrobial therapy on microbiota; and the investigation of novel formulations for human and veterinary uses. After decades of antibiotics discovery decline, antibiotics discovery is boosting. Recent developments of post genomics approaches and bioinformatics tools will most certainly turn the tide in the discovery and development of antimicrobials in this exciting field.

Whole-Cells of Yarrowia lipolytica Applied in “One Pot” Indolizine Biosynthesis

A series of yeast strains was tested in order to evaluate their catalytic potential in biocatalysis of one-pot indolizine’s synthesis. Yeast cultivation was performed in a submerged system at 28 °C for 72 h at 180 rpm. An assessment of the reagents’ toxicity on yeast viability and metabolic functionality concluded that the growth potential of three Yarrowia lipolytica strains were least affected by the reactants compared to the other yeast strains. Further, crude fermentation products (biomass and cell-free supernatant)—obtained by submerged cultivation of these yeasts—were used in multistep cascade reactions for the production of fluorescent indolizine compounds with important biologic activities. A whole–cell catalyzed multicomponent reaction of activated alkynes, α-bromo-carbonyl reagents and 4,4′-bipyridine, at room temperature in buffer solution led to the efficient synthesis of bis-indolizines 4a, 4b and 4c, in good-to-excellent yields (47%–77%). The metabolites of the selected Y. lipolytica strains can be considered effective biocatalysts in cycloaddition reactions and the high purity and bioconversion yields of the synthesized indolizines indicates a great potential of this type of “green” catalysts. Seeds of Triticum estivum L. were used to investigate the impact of the final products on the germination and seedling growth. The most sensitive physiological parameters suggest that indolizines, at the concentrations tested, have non-toxic effect on germination and seedling growth of wheat, fact also confirmed by confocal laser scanning microscopy images.