DPPH Radical Scavenging Effect Research Articles

Investigation of Cytotoxic Effects of Tragopogon reticulatus Against HepG2 and MCF-7 Cell Lines and Antioxidant, Antimicrobial Effects Against Some Microorganisms

Plants have been used for various purposes throughout history. This subject has received increasing attention in the field of traditional medicine in recent years. Tragopogon reticulatus, as a forage grass plant in turkey, is a species that stands out with rich vitamin and mineral content. The aim of this study was to investigate the antimicrobial, antioxidant, and cytotoxic activities of T. reticulatus. Two separate extracts were prepared at different concentrations using hexane and methanol solvents obtained from the T. reticulatus plant, and cytotoxic activity was evaluated by the MTT Assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) method on human liver cancer (HepG2) and human breast cancer (MCF7) cell lines. The antioxidant activity of the extracts obtained from methanol and hexane was determined by the DPPH (2,2-diphenyl 1-picrylhydrazyl) radical scavenging capacity method. Antimicrobial activity was evaluated by the disk diffusion method, and bacteria such as Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Bacillus megaterium, and Candida albicans fungus were used in the study. The hexane extract obtained from the T. reticulatus plant showed a high cytotoxic activity of 44% in the MCF7 cell line, while it showed a 51% dead cell count in the HepG2 cell line. When the antioxidant results were evaluated, it was determined that the DPPH radical scavenging effect of the hexane extract exhibited the most effective activity at 19%. When the antimicrobial results were evaluated, it was determined that the concentrations prepared with hexane exhibited the most effective activity with a zone diameter of 16 mm against B. megaterium. These findings suggest that T. reticulatus plant extracts can be considered as a potential source. These results may shed light on future research into the biological effects of the plant and contribute to the development of new treatment methods.

Therapeutic potential of selenium nanoparticles synthesized by mangrove plant: Combatting oral pathogens and exploring additional biological properties

BackgroundOver the past few decades, nanoparticles have been widely employed to limit the growth of cancer both in vivo and in vitro, as well as many dangerous bacteria, fungi, and viruses. In traditional medicine, a marine plant called Rhizophora mucronata is frequently used to treat skin conditions, inflammation, and diabetes. ObjectiveEvaluate the efficacy of selenium nanoparticles synthesized using mangrove plant extracts in combating oral pathogens and assess their potential for additional biological properties towards the development of novel therapeutic interventions for oral infections and related conditions. MethodsIn the current study, R. mucronata was utilized to create selenium nanoparticles (SeNPs) in an environmentally friendly manner. The elements of the material were identified using EDX spectroscopy, its shape was examined using SEM, and its surface Plasmon resonance was measured using UV–Vis spectroscopy. Moreover, FT-IR was used to identify the SeNPs' functional groups. ResultsThe produced nanoparticles ranged in size from 20 to 60 nm and had a spherical form. Later analyses concentrated on the ability of the synthesized nanoparticles to combat common oral pathogens that cause dental cavities and other oral diseases. The marine plant-derived SeNPs showed notable zones of inhibition in addition to lethal actions against these oral infections. These nanoparticles also demonstrated anti-inflammatory and potentially effective DPPH radical scavenging qualities. ConclusionBased on the above reported results, it can be concluded that SeNPs generated by R. mucronata have significant potential for a variety of pharmacological and medical uses.

Biological Activities, Biosorption of Heavy Metals, and Stability of Lipopeptide Biosurfactant Produced by the Alcaligenes aquatilis Bacterium YGD-2906

Background: Biosurfactants are natural products produced by microorganisms. This study examined the antioxidant activity, biosorption of heavy metals, and stability of lipopeptide biosurfactant (BLA 2906) produced by the Alcaligenes aquatilis bacterium YGD-2906. Methods: Biosurfactant production was determined by using four techniques: hemolytic test, emulsion indices, oil spreading test, and drop collapse test. The biosorption capacity of our biosurfactant to chelate the different heavy metals. The antioxidant activity was evaluated by the reducing power, phosphomolybdate tests, and DPPH•, ABTS•+ radical scavenging assays and in the end, the stability of this biosurfactant was studied. objective: Study of the heavy metal biosorption, antioxidant activity, and stability study of lipopeptide biosurfactant BLA 2906 produced by Alcaligenes aquatilis YGD-2906. Results: A negative hemolytic test, emulsion indices of 63.11 % with crude oil, 23.66 mm of oil spreading test, and a positive drop collapse test. The lipopeptide biosurfactant BLA 2906 demonstrated its ability to chelate different heavy metals at pH = 7.2, which gave biosorption capacities of Cu (II), Fe (II), Pb (II), Cd (II), and Zn (II) of 43.34, 43.60, 50.00, 20.08 and 22.48 mg /g of BLA 2906, respectively. The total antioxidant capacity of BLA 2906 presented a value of 0.84 mg Eq Trolox / g DM for the reducing power. On the other hand, the result for the phosphomolybdate test showed a value of 1029.00 ± 3.66 μg / mL to cause a 50 % reduction of the reducing activity of the phosphomolybdenum for the BLA 2906. The result of ABTS+• scavenging activity was 10.46 %. DPPH radical-scavenging effects and BHA at varying concentrations showed that concentrations required to cause 50 % inhibition were 705.48 ± 3.89 μg / ml and 7.61 ± 0.11 μg / ml for this biosurfactant and BHA, respectively. The BLA 2906 showed high stability at different temperatures, pH, and salinity in terms of emulsification activity. Conclusion: The results obtained by the lipopeptide biosurfactant BLA 2906 are attractive to invest in future applications in different fields such as industry, environment and biotechnology.

Effects of different chemical modifications on physicochemical and antioxidation properties of Lycium barbarum seed dreg polysaccharides

Recent studies have witnessed that chemical modification can improve the physicochemical and functional properties of plants' polysaccharides. Herein, we modified the natural Lycium barbarum seed dreg polysaccharides (LBSDPs) by sulfation (S-LBSDPs), phosphorylation (P-LBSDPs), and carboxymethylation (C-LBSDPs), and evaluated the chemical composition and antioxidant activity of their derivatives. Natural polysaccharides and their derivatives exhibited typical polysaccharide absorption peaks and characteristic group absorption peaks in FT-IR spectra along with maximum UV absorption. After modification, the total sugar and protein contents of the derivatives were decreased, whereas the uronic acid content was increased. Among the three derivatives, sulfated polysaccharides displayed excellent thermal stability. S-LBSDP and P-LBSDP showed the highest ABTS radical scavenging and reducing power while S-LBSDPs and C-LBSDPs showed better DPPH radical scavenging effect, and P-LBSDPs showed considerable Fe2+ chelating ability. Our data indicate that chemical modifications can impart a positive effect on the antioxidant potential of plant-derived polysaccharides.

Enzyme inhibitory effects, antioxidant properties, minerals and essential oils of Polygonum afyonicum

Total phenolic content, total antioxidant capacity, radical scavenging activity, prominent enzyme inhibitory properties, bioelement concentration and fatty acid content were determined qualitatively and quantitatively. methanol and acetone extracts of Polygonum afyonicum. The DPPH radical scavenging effect of the plant was found to be significantly different (p˂0.05) than the synthetic antioxidant butylated hydroxy toluene in the acetone extract with total phenolic content. The total antioxidant capacity of the acetone extract was higher than the methanolic extract total antioxidant status. The enzyme-inhibiting properties of acetone extract are also exceptionally high. It was found to inhibit acetylcholine esterase (86.97±3.76%) and exhibited inhibition activity as much as the standard substance galantamine (87.78±2.59%). In addition, it is seen that the tyrosinase enzyme inhibiting effect is high. Among the determined bioelements, those with the highest concentrations are Ca, K and Mg. It also contains elements (Cu, Fe, Mn and Zn) which are included in the antioxidant enzyme structure. Palmitic acid (42.5%), 1-octadecanol (9.2%) and myristic acid (7.1%) were found the most in the content of essential fatty acids and components. As a result, it was determined that the acetone extract of Polygonum afyonicum showed more antioxidative properties. The species is also prominent with its neurodegenerative effects. In addition, there is a need for structural illumination studies to reveal the metabolites responsible for biological activity by determining the phytochemicals contained in the species

Phytochemical Content of Malus floribunda: In Vitro and Molecular Docking Studies.

Malus floribunda Siebold ex Van Houtte is a plant planted for landscaping, and its sour and red fruits have been seen to be frequently used in the treatment of diabetes, making vinegar marmalade, and producing natural food dyes. Apart from these usage areas of this plant, it is aimed at determining the phytochemical content. For this purpose, plant parts (fruit, leaf, and branch) were examined. The antioxidant capacity (vitamins A, E, and C, lycopene, beta-carotene, total phenolic and flavonoid amounts, and DPPH radical scavenging effect), antimicrobial activity (agar well diffusion method, minimum inhibitory concentration-MIC), and GC-MS contents of plant parts were determined. High-performance liquid chromatography (HPLC), spectrophotometers, and gas chromatography/mass spectroscopy (GC-MS) methods were used in the study. It was determined that M. floribunda fruit is rich in lycopene, beta-carotene, and antioxidant vitamins and contains many biomolecules. In addition, it was concluded that the extracts of different parts of the plant have antimicrobial activity. This study has revealed the idea that this plant, whose phytochemical, antioxidant, and antimicrobial content has been determined, can be used as a bioactive substance equivalent to antibiotics in medicine, the food industry, and human nutrition. In addition, it is expected that the study will contribute to the plant literature. Molecular docking studies were performed to evaluate the binding interactions between the compound and human peroxiredoxin 5 and S. aureus. Both in vitro and in silico results indicated that synthesized extracts could act as potent antioxidant and antimicrobial agents.

Analysis of Antioxidant Property from Water Extraction of Garcia Mangostana Using Response Surface Methodology

Mangosteen (Garcia mangostana) is an exotic fruit that can be found widely in Southeast Asia. Mangosteen pericarp contains bioactive compound that has pharmacological properties, including antioxidants, anticarcinogenic, and also suggested its applicability for skincare products. Water extraction is more applicable for industry due to simple process, low cost, and neutral reaction. In this study, water extraction on the pericarp of mangosteen was applied and the operating parameters were discussed by using Response Surface Methodology (RSM) for high recovery of antioxidant extract from the mangosteen pericarp. The experimental design used three factors, solid-to-liquid ratio (g/ml), temperature (oC) and extraction time (hour), were analyzed to discuss two responses, DPPH radical scavenging effect (DPPH) and Ferric Reducing Antioxidant Power (FRAP). Under the operating conditions, the highest FRAP is 0.818 abs at the factors of 1:10 (g/ml), 65 oC, and 3-hour. DPPH is significantly high for all RSM pattern. The optimum parameters determined by using RSM are at 1:10 (g/ml), 59.74 oC, and 2.87 hours with DPPH 81.01% and FRAP 0.789 abs.

Geigeria alata- a potential source for anti-Alzheimer’s constituents: In vitro and computational investigations

Antioxidants and acetylcholinesterase inhibitors play a key role in the prevention and management of degenerative disorders including Alzheimer’s disease in particular. Identifying new anticholinesterases from natural sources may contribute to combating this class of diseases. The present study aimed to evaluate the potential anti-Alzheimer’s activity of Geigeria alata (DC), a plant used in Sudanese folkloric medicine. Accordingly, the whole DC plant extract including twenty phytoconstituents of phenolic, flavonoid, and tannin types was evaluated in vitro as antioxidants and acetylcholinesterase inhibitors. As well, their pharmacokinetics, drug likeliness, and toxicity profiles were assessed. Additionally, the virtual binding of the plant’s phytoconstituents with the cholinesterase target was investigated by docking against two AChE X-ray crystallographic structures. The best effective DPPH radical scavenging activity was demonstrated by both ethyl acetate and n-butanol fractions with percentages of inhibition of 91 ± 0.02% and 90 ± 0.02% (IC50 22 ± 0.01 and 66 ± 0.02 µg/mL), respectively. The ethyl acetate fraction showed statistically significant, and the highest AChE inhibitory activity (78% inhibition, IC50 0.246 ± 0.02 mg/mL). Furthermore, the ethyl acetate fraction exhibited the highest total phenolic, flavonoid, and tannin values. Among identified compounds, quercetin and hispidulin showed promising in silico anti-AChE activity and hence merit further studies for the isolation and characterization of these active constituents.

Effects of extracting solvents on phytochemical, antioxidant, and antibacterial activity of some seaweeds from the Bay of Bengal offshore Island

Seaweed is a rich source of bioactive compounds. Therefore, searching of natural antioxidant and antibacterial agents as alternatives to a synthetic counterpart is of great interest. The effects of various extracting solvents (viz. methanol, ethanol, and acetone) on the phytochemical content, antioxidant, and antibacterial activity of seven seaweeds consisting of three brown seaweeds (Sargassum natans, Sargassum fluitans, Spatoglossum asperum), three red seaweeds (Hypnea pannosa, Hypnea musciformes, Porphyra linearis) and one green seaweed (Ulva lactuca) were evaluated. The antioxidant capacity of crude extracts was evaluated by total antioxidant activity (TAA), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and cupric reducing antioxidant capacity (CUPRAC) assays. Seaweed extracts were also tested against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa by agar well diffusion method. The total phenolic content (TPC) of seaweed extracts varied significantly (P < 0.05) ranging from 51.08 ± 0.72–74.62 ± 1.15 mg GAE/g. Methanolic extracts of S. natans showed significantly the highest TPC, total flavonoid content (79.22 ± 5.21 mg QE/g), and TAA (57.79 ± 4.35 mg AA/g) than other seaweed extracts. Methanolic extracts of S. natans also exhibited the highest DPPH and ABTS radical scavenging effects (EC50 = 0.74 ± 0.04 and 0.14 ± 0.01 mg/ml, respectively). While, methanolic and ethanolic extracts of S. natans showed significantly the highest effective concentration (ECA0.50) value (0.19 ± 0.02 mg/ml and 0.14 ± 0.02 mg/ml, respectively) of CUPRAC. Pearson's correlation test and principal component analysis showed the relation between TPC and various antioxidant activity assays of seaweed extracts. The seaweed methanolic extracts showed a comparatively higher zone of inhibition against all the bacterial strains than other solvent extracts. However, all the solvent extracts of U. lactuca were almost inactive against all the bacterial strains. The results of this study demonstrated that methanolic extracts of brown seaweeds showed comparatively better antioxidant and antibacterial activity, which could be used in the food and pharmaceutical applications.

Helichrysum arenarium subsp. (L.) Moench aucheri’nin Farklı Ekstraktlarının Antimikrobiyal ve Antioksidan Aktivitesi

Helichrysum arenarium (L.) Moench subsp. aucheri is a herbaceous perennial herb belonging to the Asteraceae. This plant has biological activities such as antibacterial, antiviral, anti-inflammatory, antifungal, antiproliferative, antioxidant, and antiradical. In this study, antimicrobial and antioxidant activities of methanol and ethanol extracts of aerial parts of H. arenarium subsp. aucheri were investigated. To determine the antimicrobial activity pathogenic microorganisms Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus megaterium, Candida glabrata, Candida albicans and Trichophyton sp. Antioxidant activity was determined with total antioxidant value (TAS), total oxidant value (TOS) and 2.2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging capacity. In the results obtained, it was determined that the methanol extract had an antimicrobial effect (9.3 mm) only against C. albicans. It was found that the ethanol extract showed antimicrobial activity at different rates (8.8-20.4 mm) against S. aureus, B. megaterium, C. glabrata, C. albicans and Trichophyton sp. The TAS value of the methanol extract was 3.00 mmol, and the TAS value of the ethanol extract was 3.15 mmol. The TOS value of the methanol extract of the same species was calculated as 6.81 μmol, and the TOS value of the ethanol extract was calculated as 12.64 μmol. The DPPH radical scavenging effects of extracts of goldengrass was found to increase depend on concentrations.

ANTIOXIDANT, ENZYME INHIBITORY, AND CYTOTOXIC ACTIVITY SCREENING OF MYRTUS COMMUNIS L.

Objective: The present study aimed to evaluate the biological activities of Myrtus communis L., which has traditional medicinal use for different purposes, from a broad perspective. Material and Method: The antioxidant (DPPH, ABTS, total phenol, and flavonoid amounts) anti-inflammatory (LOX enzyme inhibition), antidiabetic (α-glucosidase enzyme inhibition), and cytotoxic properties (MTT assay) of a 70% methanol extract made from leaves and dichloromethane, butanol, ethyl acetate, and the residual water fractions were investigated. Result and Discussion: The DPPH radical scavenging effect of the ethyl acetate fraction, with the highest total phenol and flavonoid content, was found to be 1.4 µg/ml, and the ABTS radical scavenging effect was 2.58 mmol/Trolox. The most potent inhibitor of LOX (IC50: 31.17 µg/ml) and α-glucosidase (96% inhibition at 0.5 mg/ml) enzymes was determined as ethyl acetate extract. Dichloromethane fraction was shown to have the most cytotoxic activity in both Hela and Colo cell lines. This research has given us a better understanding of the traditional use of the M. communis plant, which stands out for its therapeutic properties.

Evaluation of antioxidant and antibacterial activities of some selected seaweeds from Saint Martin's Island of Bangladesh

The effects of extracting solvents on the antioxidant and antibacterial activity of crude extracts of six seaweeds were investigated. The antioxidant activity of seaweed crude extracts was evaluated by total antioxidant activity (TAA), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt (ABTS), and cupric reducing antioxidant capacity (CUPRAC) assays. Acetone extract of B. wrightii showed significantly (P < 0.05) the highest total phenolic content (TPC) (71.09 mg GAE/g), while methanolic extract of Porphyra sp. had the highest total flavonoid content (75.61 mg QE/g). Methanolic extract of S. muticum showed significantly (P < 0.05) the highest TAA. Methanolic extract of P. tetrastromatica and S. muticum showed significantly (P < 0.05) the highest DPPH and ABTS radical scavenging effects, while acetone extract of B. wrightii showed significantly the highest ECA0.50 value (0.78 mg/ml) of CUPRAC activity. Pearson's correlation test and principal component analysis (PCA) confirmed the relationship between TPC and various antioxidant activity assays of seaweed extracts. Methanolic extracts of P. tetrastromatica, S. muticum and H. clathratus showed higher inhibitory zones against all the bacterial strains than other seaweed extracts. The results of this study indicated that brown seaweeds showed comparatively better antioxidant and antibacterial activity, which could be utilized in the food processing industries.

A Physicochemical Study of the Antioxidant Activity of Corn Silk Extracts.

Corn silk (CS) extracts are reported to contain flavonoids (appx. 59.65 mg quercetin/g), polysaccharides (appx. 58.75 w.%), steroids (appx. 38.3 × 10-3 to 368.9 × 10-3 mg/mL), polyphenols (appx. 77.89 mg/GAE/g) and other functional biological substances. This study investigated the antioxidant activity of corn silk extracts related to their functional compounds. The radical scavenging effect of corn silk extracts was evaluated by the spin-trapping electron paramagnetic resonance (EPR) technique, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonate) (ABTS•+) free radical measurement, ferric ion-reducing antioxidant power, and copper ion reductive capacity. It was found that the maturity stage of CS plant materials and the applied extraction procedure of their bioactive compounds have a profound effect on the radical scavenging capacity. Differences in the antioxidant activity of the studied corn silk samples based on their maturity were also confirmed. The strongest DPPH radical scavenging effect was observed for the corn silk mature stage (CS-M)stage (CS-MS) (65.20 ± 0.90)%, followed by the silky stage (CS-S) (59.33 ± 0.61)% and the milky stage (CS-M) (59.20 ± 0.92)%, respectively. In general, the final maturity stage (CS-MS) provided the most potent antioxidant effect, followed by the earliest maturity stage (CS-S) and the second maturity stage (CS-M).

Development of propolis extract-loaded nanoparticles with chitosan and hyaluronic acid for improving solubility and stability

Propolis extract (PE) is a natural polyphenol with various biological activities; however, its application is limited due to low solubility and instability. To overcome these drawbacks, we encapsulated PE in nanoparticles (PE-loaded nanoparticles, PE-NP) using chitosan (CS) and hyaluronic acid (HA) as wall materials. We examined the physicochemical characteristics (size, polydispersity index, zeta potential, and entrapment efficiency) of PE-NP prepared with the various ratios of CS to HA and core to the wall material, and confirmed the optimal ratio for the formulation of PE-NP as 4:7 and 1:2, respectively. In addition, PE-NP significantly increased the solubility of PE by 2.43-fold compared to that of free PE (p < 0.05). Moreover, the retention rate of total flavonoid content (TFC) in PE-NP was significantly higher than that in free PE after the heat treatment (90 °C) for 24 h (p < 0.05). Furthermore, PE-NP showed significantly higher retention rates of TFC and DPPH radical scavenging effects than free PE after storage for 4 weeks at 30 and 50 °C (p < 0.05). In conclusion, these findings suggest that PE-NP may be a promising approach to enhance the solubility and stability of PE and could provide helpful information for expanding the application of PE.

Pyrogallol is a key component for xanthine oxidase inhibition by the leaves of Ammannia baecifera

Ammannia baecifera Linn is an important plant in traditional medication system of Bangladesh. In order to give the scientific clarification for using this plant in the treatment of gout, this study was designed to identify the xanthine oxidase (XO) inhibitors present in the extract of Ammannia baecifera leaves along with evaluating its antioxidant effect. First aqueous extract was prepared from leaves and then water insoluble part (WIP) was separated from water soluble part (WSP) as precipitate with ethanol. In DPPH and ABTS assays, WSP with rich amount of phenolic compound exhibited high radical scavenging activity than WIP. WSP also showed potent XO inhibition with IC50: 18.03 ± 1.65 μg/mL value. Using different chromatographic techniques, the key XO inhibitor was isolated from WSP and identified as pyrogallol based on its different spectroscopic data. In XO inhibition assay, pyrogallol (IC50: 11.67 ± 0.45 μg/mL) showed potent inhibitory effect as compared to a known XO inhibitor (allopurinol; IC50 = 27.35 ± 1.15 μg/mL) and it also displayed strong DPPH and ABTS radical scavenging effect. In addition, an inhibition kinetics study indicated that WSP and pyrogallol are mixed competitive inhibitors of XO. The overall results suggest that the presence of pyrogallol as XO inhibitor and free radical scavenger in Ammannia baecifera leaf justifies the traditional uses of this plant.&#x0D; Keywords: Ammannia baecifera, Leaves, Xanthine oxidase, Pyrogallol, Inhibitor

Comparative Phytochemical and Antioxidant Analysis of the Leaf Extracts of Two Nigerian Medicinal Plants

Bridelia ferruginea (Benth., Euphorbiaceae), prominently found in Savannah regions, is commonly used as an ethnomedicine for the treatment of several ailments in many parts of Africa. Piliostigma thonningii (Schum., Fabaceae) is used for various medicinal purposes in African countries with some pharmacological activities established from the crude extracts including antibacterial, antihelminthic, antiinflammatory and antilipidemic activities. In the present study, crude methanolic extract and fractions of B. ferruginea and P. thonningii were examined for their phytochemical constituents and antioxidant activity using standard protocols. Qualitative phytochemical screening of B. ferruginea crude extract revealed the presence of tannins, saponins, phlobatanins, flavonoids, steroids, alkaloids, glycosides, phenols and resins while it tested negative for triterpenoids, carbohydrates, terpenoids and anthraquinones; the quantitative phytochemical analysis showed that it contained 1.5% saponins, 5.3% flavonoids, 1.2% alkaloids and 0.9% phenols. P. thonningii crude extract tested positive for saponins, flavonoids, terpenoids, steroids, alkaloids, and phenols while tannins, phlobatanins, glycosides, triterpenoids, carbohydrates, resins and anthraquinones were absent. It contains 3.2% saponins, 1.6% flavonoids, 1.8% alkaloids, and 0.7% phenols. The concentration of the crude extract required for 50% inhibition of DPPH radical scavenging effect (IC50) is 0.018 and 0.020 mg/ml for B. ferruginea and P. thonningii, respectively, compared to 0.015 mg/ml for vitamin C as a standard antioxidant. Both extracts showed potent inhibition of DPPH radical scavenging activity comparable to that of the Vitamin C standard and would be valuable sources of antioxidant compounds.

Dysosmaflavonoid A–F, new flavonols with potent DPPH radical scavenging activity from Dysosma versipellis

Six new flavonols, including four glucosylated flavonols (dysosmaflavonoid A–D), one phenylpropanoid-substituted flavonol (dysosmaflavonoid E), and one phenyl-substituted flavonol (dysosmaflavonoid F), together with five known analogues, were isolated from the roots and rhizomes of Dysosma versipellis. Their structures were elucidated by comprehensive analysis of their NMR, IR, UV, HRESIMS, and HPLC data. The antioxidant activities of all isolated compounds were examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Compounds 2, 3, 5–8, and 12 exhibited significant DPPH scavenging capacity with IC50 values of 33.95, 39.02, 31.17, 32.79, 31.85, 30.48, and 23.75 μM, respectively, in comparison with Trolox (IC50, 15.80 μM). Compound 12 displayed more potent DPPH radical scavenging activity than prenylated and (or) glucosided derivatives (2–4, or 10). The preliminary structure-activity relationship showed that the catechol structure in flavonol is essential for DPPH radical scavenging effect.

Antioxidant, Anti-Inflammatory and Attenuating Intracellular Reactive Oxygen Species Activities of Nicotiana tabacum var. Virginia Leaf Extract Phytosomes and Shape Memory Gel Formulation.

Oxidative stress is one of the major causes of skin aging. In this study, the shape memory gels containing phytosomes were developed as a delivery system for Nicotiana tabacum var. Virginia fresh (VFL) and dry (VDL) leaf extracts. The extracts were loaded in the phytosomes by a solvent displacement method. The physical and chemical characteristics and stability of phytosomes were evaluated by dynamic light scattering and phytochemistry, respectively. The in vitro antioxidant activity and intracellular reactive oxygen species reduction of phytosomes and/or extracts were investigated by the DPPH and ABTS radical scavenging assays, FRAP assay, and DCFH-DA fluorescent probe. The cytotoxicity and anti-inflammatory activity of VDL and VFL phytosomes were studied by an MTT and a nitric oxide assay, respectively. Here, we first reported the total phenolic content in the dry leaf extract of N. tabacum var. Virginia was significantly greater than that of the fresh leaf extract. The HPLC analysis results revealed that VDL and VFL extracts contained 4.94 ± 0.04 and 3.13 ± 0.01 µg/mL of chlorogenic acid and 0.89 ± 0.00 and 0.24 ± 0.00 µg/mL of rutin, respectively. The phytosomes of the VDL and VFL extracts displayed stable size, polydispersity index, zeta potential values, and good chemical stability. VDL and VDL phytosomes showed higher phenolic and flavonoid contents which showed stronger DPPH and ABTS radical scavenging effects and reduced the intracellular ROS. The results suggested that the phenolic compounds are the main factor in their antioxidant activity. Both VDL and VFL phytosomes inhibited nitric oxide production induced by LPS, suggesting the anti-inflammatory activity of the phytosomes. The shape memory gel containing VDL and VFL phytosomes had good physical stability in terms of pH and viscosity. The VDL and VFL phytosomes dispersed in the shape memory gels can be considered as a promising therapeutic delivery system for protecting the skin from oxidation and reactive oxygen species.

Phytochemical Study and In Vitro Biological Activities of Hibiscus panduriformis Burm. f. (Malvaceae), Alternanthera pungens Kunth (Amaranthaceae), and Wissadula rostrata (Schumach.) Hook. f. (Malvaceae).

The present study investigated the phytochemical content of Hibiscus panduriformis, Alternanthera pungens, and Wissadula rostrata and assessed their radical scavenging and anti-inflammatory properties. n-Hexane, dichloromethane (DCM), ethyl acetate, and methanol extracts were prepared from the powdered plant parts. The phytochemical analysis was performed using qualitative high-performance thin-layer chromatography, and polyphenols were quantified using well-established methods. The anti-inflammatory effect was by lipoxygenase inhibition, while the antiradical impact was evaluated through DPPH and ABTS radicals. Steroids, triterpenoids, flavonoids, and tannins were identified in the three plants. The highest phenolic content (95.67 ± 2.19 mg gallic acid equivalent/g) was obtained in the methanolic extract of W. rostrata, while the lowest was measured in H. panduriformis. H. panduriformis was found to be highly rich in flavonoids (61.22 ± 0.09 mg rutin equivalent/g), condensed tannins (62.53 ± 0.03 mg catechin equivalent/g), and hydrolyzable tannins (125.1 ± 1.02 mg tannic acid equivalent/g). The methanolic extract of H. panduriformis displayed the greatest antilipoxygenase activity with an IC50 value of 8.78 ± 1.05 μg/mL. It should be noted that although a moderate to low effect was observed, the extracts were more likely to scavenge DPPH (IC50 values ranged from 0.106 ± 0.010 to 1 mg/mL) than ABTS radicals. There was a strong to moderate correlation between the antilipoxygenase and DPPH radical scavenging effects of the methanolic extracts and total phenolic content (antilipoxygenase, r = 0.7175; DPPH, r = 0.9376). Furthermore, it is worth noting that this is the first report investigating the phytochemical analysis and in vitro biological properties of Hibiscus panduriformis. The results highlighted the richness of this plant in polyphenols and demonstrated its high and moderate effects on lipoxygenase and DPPH radicals, respectively. To this intent, further in vivo and in vitro studies on this plant, along with exhaustive phytochemical analysis, are needed.

Dictamnus albus L’ a Ait. Ekstrelerin PC-12 ve SHSY-5Y Hücre Hatlarında Toksik Etkilerinin Değerlendirilmesi ve Antioksidan Aktivitesinin Araştırılması

This study investigated the antioxidant and cytotoxic properties of the Dictamnus albus L. plant grown in Türkiye. The aerial parts and roots of the plant were evaluated qualitatively in terms of chemical content. Total phenol and flavonoid amounts were calculated by spectrophotometric methods, antioxidant activity was tested with DPPH and ABTS radical scavenging activity assay. In addition, cell viability determination in PC-12 and SHSY-5Y cell lines was evaluated by performing MTT (3-4,5-dimethyl-thiazolyl-2,5-diphenyltetrazolium bromide) test. According to the results, both parts of the plant gave negative results in the tannin, cyanogenetic glycoside, anthraquinone, cardiac glycoside, and anthocyanoside identification tests, while they gave positive results in the alkaloid, coumarin, saponin, carbohydrate identification tests. While the total amount of phenol was calculated as 77.13 ± 5.73 mgGAE gexracts-1 in the extract prepared with methanol from the aerial parts of the plant (D.A Herba), it was calculated as 43.81 ± 9.49 mgGAE gexracts-1 in the extract prepared from the roots (D.A Root). The total flavonoid content could only be calculated in the D.A Herba extract (19.11 ± 0.16 mgCA gextract-1). Although the DPPH radical scavenging effect of the extracts was higher in D.A Herba extract, the ABTS radical scavenging effects were found similar in both D.A Herba and D.A Root extracts. According to the toxicity test, D.A Root extract reduced the viability below 50% (43.17 ± 3.44%) at 500 µg mL-1, but D.A Herba extract was found to be more toxic at the same concentration with 19.53 ± 0.183% in the PC-12 cell line. However, D.A. Herba and D.A.Root extract increased cell proliferation in the SHSY-5Y cell line at 3.25 µg/mL concentrations with 122.87±6.29 and 112.78±7.00%, respectively. The results suggest that D. albus may be a promising candidate for the new phytopharmaceuticals due to its neuroprotective effects.