The Aerial Parts of Agrimonia procera Wallr. and Agrimonia eupatoria L. as a Source of Polyphenols,and Especially Agrimoniin and Flavonoids

Plants of the genus Agrimonia L. perfectly fit the current trends in nutrition and food technology, namely, the need for raw materials with a high content of bioactive natural compounds, including polyphenols, which could be added to food. The composition of polyphenolics, including agrimoniin and flavonoids, in the aerial parts of Agrimonia procera Wallr. (A. procera) and Agrimonia eupatoria L. (A. eupatoria) (Rosaceae) was determined using HPLC-DAD-MS. The polyphenolic content of A. procera was found to be 3.9%, 3.2%, 2.9%, 1.8% and 1.1%, and that of A. eupatoria was determined to be 1.3%, 0.3%, 0.9%, 0.6% and 0.5% in the dry matter of leaves, stems, fruits, seeds and hypanthia, respectively. Except for A. procera hypanthia, agrimoniin was the main polyphenolic compound in the aerial parts of the studied Agrimonia species. Both plants are also a valuable source of flavonoid glycosides, especially apigenin, luteolin and quercetin. The obtained data indicate that both A. procera and A. eupatoria are potentially good sources of polyphenols (albeit significantly different in terms of their qualitative and quantitative composition), and may not only be a medicinal raw material, but also a valuable material for food use such as nutraceuticals or functional food ingredients.     

Bioactive compounds content and their biological properties of acetone extract of Cuscuta reflexa Roxb. grown on various host plants

The present study is aimed to evaluate the total phenolic and flavonoid contents, and free phenolic compounds of acetone extract of Cuscuta reflexa grown on five different hosts: Coccinia grandis, Ficus racemosa, Samanea saman, Streblus asper and Zollingeria dongnaiensis, and to explore the antioxidant activities, α-glucosidase and tyrosinase inhibitory properties of the extracts. The highest level of total phenolic and flavonoid contents were observed in the extract of C. reflexa that was grown on S. asper (65.45 mg GAE/g extract) and C. grandis (97.83 mg QE/g extract), respectively. According to HPLC results, vanillic acid, rutin and quercetin were found in all extracts of C. reflexa grown on diversified hosts. The extract of C. reflexa grown on C. grandis possessed the greatest antioxidant activities (DPPH; 251.64 μg/mL, FRAP; 26.44 mg GAE/g extract), α-glucosidase inhibition accounted for 84.36 per cent and antityrosinase activity was at 18.29 mg KAE/g sample.     

Calotropis procera extract induces apoptosis and cell cycle arrest at G2/M phase in human skin melanoma (SK-MEL-2) cells

Calotropis procera (family: Asclepiadaceae) contains cardiac glycosides which are cytotoxic to cancer cells. The extracts of C. procera have been reported to be cytotoxic to many cancer cell lines and this is the first report against the human skin melanoma cells (SK-MEL-2). The SK-MEL-2 cells treated with C. procera methanolic extract (CPME) were analysed for growth inhibition and apoptosis. The exposure of phosphatidylserine in apoptotic SK-MEL-2 was analysed by using the Annexin-V FITC flow cytometry method. In CPME-treated SK-MEL-2 cells, 19.6% of apoptotic and 58.3% dead cells were observed. The 15.97% and 15.85% of early apoptotic cells were found at 20 μg/mL of the ouabain and paclitaxel, respectively. Active caspases, nuclear degradation confirmed apoptotic SK-MEL-2 cells in time- and dose-dependent manner. The cell cycle analysis shows that CPME treated cells halt at G2/M phase. Significant cytotoxic activity of CPME against SK-MEL-2 may be attributed to its high cardenolide content.     

Phytochemical composition,in vitro antioxidant activity and antibacterial mechanisms of Neolamarckia cadamba fruits extracts

Aqueous extracts of Neolamarckia cadamba fruits prepared at different maturity stages were used for the analysis of various phytochemicals, and their antioxidant and antibacterial activities were determined. Ripe fruit extract had highest phenolics (3.14 mM GAE/ g fruit extract) with caffeic acid, tannic acid, syringic acid and quercetin as major phenolic compounds. The ripe fruit extract showed lowest IC₅₀ values in DPPH radical scavenging assay (231.33 μg fruit extract/ mL), and highest ABTS radical scavenging activity (111.18 μM TEAC/g). Immature fruit extract showed lowest minimum inhibitory concentration against tested bacteria, and the antibacterial activity was probably due to membrane permeation, as was evident by leakage of genetic material and reduction in propidium iodide uptake by bacterium; and by inhibition of sugar and amino acid uptake. The appreciable amount of phenolic compounds and biological activities in the aqueous extracts of N. cadamba fruits suggests it's potential application as natural preservative.     

Antioxidant,antimicrobial and urease inhibiting activities of methanolic extracts from Cyphostemma digitatum stem and roots

Cyphostemma digitatum stem and roots extracts were investigated for antioxidant, antimicrobial, urease inhibition potential and phytochemical analysis. Phytochemical screening of the roots and stem extract revealed the presence of secondary metabolites including flavonoids, alkaloids, coumarins, saponins, terpenoids, tannins, carbohydrates/reducing sugars and phenolic compounds. The methanolic extracts of the roots displayed highest antioxidant activity (93.518%) against DPPH while the crude methanolic extract of the stem showed highest antioxidant activity (66.163%) at 100 μg/mL concentration. The methanolic extracts of both stem and roots were moderately active or even found to be less active against the selected bacterial and fungal strains (Tables S2 and S3). The roots extract (methanol) showed significant urease enzyme inhibition activity (IC₅₀ = 41.2 ± 0.66; 0.2 mg/mL) while the stem extract was found moderately active (IC₅₀ = 401.1 ± 0.58; 0.2 mg/mL) against thiourea (IC₅₀ = 21.011; 0.2 mg/mL).     

Modulation of antibiotic activity by the hydroalcoholic extract from leaves of Caryocar coriaceum WITTM

The aim of this study was to identify the presence of tannins, phenols and flavonoids on the hydroalcoholic extract of Caryocar coriaceum leaves (HECCL) and to determine the antioxidant and antibacterial activity of this extract. The extract was tested alone (1024–1 μg/mL) or associated (MIC/8) with several antibiotics in order to identify any antibacterial activity against multiresistant bacterial strains (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa). The existence of tannins, total phenols (901.31 mg/g) and flavonoids (89.68 mg/g) was confirmed in the HECCL. The presence of rutin and quercetin were confirmed by Thin-layer chromatography (TLC). Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, the antioxidant activity of the extract (9 μg/mL) was determined. Moreover, the Minimum Inhibitory Concentration (MIC) value found for HECCL was 1024 μg/mL and the association between HECCL (MIC/8) with benzylpenicillin significantly changed its minimum inhibitory concentration from 2500 to 625 μg/mL against E. coli.     

A new ultra-high pressure liquid chromatography method for the determination of antioxidant flavonol aglycones in six Lysimachia species

UPLC-DAD method was developed and validated for the quantitative determination of free flavonol aglycones (kaempferol, quercetin and myricetin) after acidic hydrolysis in six Lysimachia species. Quantitative analyses showed that the amounts of various flavonol aglycones were significantly different in Lysimachia vulgaris, Lysimachia nummularia, Lysimachia punctata, Lysimachia christinae, Lysimachia ciliata and Lysimachia clethroides. The L. clethroides sample was found to be the richest in kaempferol (25.77 ± 1.29 μg/mg extract) and quercetin (97.67 ± 4.61 μg/mg extract), while the L. nummularia sample contained the highest amount of myricetin (20.79 ± 1.00 μg/mg extract). The antioxidant capacity of hydrolysed extracts was evaluated using in vitro DPPH^? (2,2-diphenyl-1-picrylhydrazyl) and ABTS^?+ [2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] decolourisation tests. The observed radical scavenging capacities of the extracts showed a relationship with the measured flavonol aglycone content and composition. The acidic treatment resulted in an increased free radical scavenging activity compared to the untreated methanol extract.     

Antioxidant,cholinesterase inhibition activities and essential oil analysis of Nelumbo nucifera seeds

Nelumbo nucifera seeds’ essential oil (EO), crude extract and subsequent fractions were evaluated for their DPPH, ABTS and superoxide anion-free radical scavenging and cholinesterase inhibitory activities. The ethyl acetate fraction and EO showed outstanding antioxidant activities with IC₅₀ values of 191, 450 μg/mL (DPPH), 123, 221 μg/mL (ABTS) and 69, 370 μg/mL (superoxide anion). The ethyl acetate fraction and EO also caused significant inhibition of acetylcholinesterase and butyrylcholinesterase with IC₅₀ values of 70 ± 0.6, 64 ± 0.8 and 75 ± 0.3, 58 ± 0.2, in dose-dependent manner. The first ever gas chromatography–mass spectrometry analysis of the EO obtained from N. nucifera seeds resulted in identification of 19 constituents, mainly comprised of oxygenated sesquiterpenes responsible for their promising bioactivity. The crude and fractions revealed the presence of saponins, flavonoids, steroids, alkaloids, terpenoids and cardiac glycosides in phytochemical investigation.     

Egyptian herbal tea infusions' antioxidants and their antiproliferative and cytotoxic activities against cancer cells

The antioxidant, antiproliferative and cytotoxic activities against different human cancer cells were investigated in local and recently introduced plants of Mentha sp., Rosmarinus officinalis L. (ROL) and Origanum majorana L. (OML). ROL exhibited the highest antioxidant activities (IC₅₀ 8.4 ± 0.2 μg/mL) followed by OML and mint species such as Mentha suaveolens ‘apple mint’ and Mentha longifolia L. exhibiting moderate antioxidant activities. HPLC analysis of leaf extract revealed that rosmarinic acid is the main component followed by caffeic acid. Herbal leaf extracts varied in their proliferation inhibition and cytotoxicity against HeLa, MCF-7 and Jurkat cancer cells in a dose-dependent matter. The highest antiproliferative inhibition and cytotoxic activity were detected in ROL and OML followed by mint. Local herbs might have a potential role as anticancer natural medicines in addition to their high antioxidant activities due to the presence of different phenolics in their aqueous tea extracts.     

Polyphenolic profiling of Ipomoea carnea Jacq. by HPLC-DAD and its implications in oxidative stress and cancer

Ipomoea carnea Jacq. is an important folklore medicinal plant, assessed for its underexplored biological potential. Antioxidant, cytotoxic, antiproliferative and polyphenolic profile of whole plant was evaluated using various techniques. Maximum extract recovery (29% w/w), phenolic [13.54 ± 0.27 μg GAE/mg dry weight (DW)] and flavonoid (2.11 ± 0.10 μg QE /mg DW) content were recorded in methanol-distilled water (1:1) flower extract. HPLC-DAD analysis quantified substantial amount of six different polyphenols ranging from 0.081 to 37.95 μg/mg extract. Maximum total antioxidant and reducing potential were documented in methanol-distilled water and acetone-distilled water flower extracts (42.62 ± 0.47 and 24.38 ± 0.39 μg AAE/mg DW) respectively. Ethanol-chloroform root extract manifested highest free radical scavenging (IC₅₀ of 61.22 μg/mL) while 94.64% of the extracts showed cytotoxicity against brine shrimps. Ethanol leaf extract exhibited remarkable activity against THP-1 cell line (IC₅₀ = 8 ± 0.05 μg/mL) and protein kinases (31 mm phenotype bald zone).     

The natural phenolic compounds and their antioxidant and anticholinesterase potential of herb Leiotulus dasyanthus (K. Koch) Pimenov & Ostr.

Abstract

The presented work reports anticholinesterase and antioxidant activities of extracts, fractions from aerial parts, fruits, flowers, roots and isolated compounds of roots from Leiotulus dasyanthus (bergapten, pimpinellin, umbelliferone, quercetin, rutin and kaempferol). Phenolic contents, antioxidant activities of samples were carried out by Folin-Ciocalteu, DPPH, TBA methods. Anticholinesterase activity was evaluated by Ellman’s method. The highest and lowest total phenolic content were detected in root MeOH extract (88.6?mg GAE g^?1 DW) and aerial part (51.83?mg GAE g^?1 DW), respectively. The highest antioxidant activity among isolated secondary metabolites got coumarins umbelliferone, bergapten and pimpinellin. Pimpinellin (66.55%) and umbelliferone (61.09%) demonstrated strong inhibition towards acetylcholinesterase and butyrylcholinesterase, respectively. Dichloromethane fraction of root demonstrated significant inhibition against AChE (49.66%) and BuChE (92.21%) at 20 µg/mL. Dichloromethane fractions of roots had a notableness antioxidant and anticholinesterase activities. The further studies on roots will be important for development use of this plant for pharmaceutical and food research needs.

     

Phytochemical characterisation and bioprospection for antibacterial and antioxidant activities of Lippia alba Brown ex Britton & Wilson (Verbenaceae)

Ethanol extract and fractions obtained from fresh and dry aerial parts of Lippia alba were examined in order to determine their phytochemical composition, antioxidant capacity and antibacterial activities. The ethanol extracts and fractions exhibited an antioxidant effect by the DPPH assay, especially samples of fresh plant. HPLC analysis of the ethyl acetate fractions identified the presence of phenolic acids and flavonoids. The ethanol extract and fractions showed activity against reference and multidrug-resistant strains of Staphylococcus aureus and Enterococcus faecalis (MIC range 2000–250 μg/mL). The hexane and dichloromethane fractions of fresh plant showed better activity against reference strains of Escherichia coli (MIC of 250 and 125 μg/mL, respectively), but all extracts and fractions were less active against multidrug-resistant strains of all the Gram-negative species evaluated. The results showed that the extract and fractions of L alba aerial parts showed antibacterial activity, even against multidrug-resistant Gram-positive bacteria, and antioxidant effect (DPPH assay).     

Phytochemical profile and biological activities of Deverra tortuosa (Desf.)DC.: a desert aromatic shrub widespread in Northern Region of Saudi Arabia

The present study describes the chemical composition of the essential oil of different plant parts of Devrra tortuosa; in vivo and in vitro biological activities of plant extract and essential oils. Apiol was found to be the major component of the oil (between 65.73% and 74.41%). The best antioxidant activities were observed for the oil of flowers (IC50 = 175 μg/ml). The samples of stems and roots exhibit lower antioxidant activity (IC50 = 201 μg/ml and 182 μg/ml, respectively). The values of IC50 showed that the extracts of methanol exhibit the highest antioxidants activities (IC50 = 64.8 102 μg/ml). EOs showed excellent antifungal activity against yeasts with low azole susceptibilities (i.e. Malassezia spp. and Candida krusei). The MIC values of oils varied between 2.85 mg/mL and 27 mg/mL. The obtained results also showed that the plant extracts inhibited the germination and the shoot and root growth of Triticum æstivum seedlings.     

Quantification of polyphenols and flavonoid content and evaluation of anti-inflammatory and antimicrobial activities of Stenocereus stellatus extracts

The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) – induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography–mass spectrometry (GC–MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 μg/mL) and Rhizopus sp. (15 μg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, β-sitosterol, β-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species.     

Phenolic,flavonoid contents,anticholinesterase and antioxidant evaluation of Iris germanica var; florentina

This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman’s assay. Antioxidant activity was performed using DPPH, H₂O₂ and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC₅₀ values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC₅₀ of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC₅₀ = 9 μg/mL) and 78.30% (IC₅₀ = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC₅₀ values of < 0.1, 2, 2 and 3 μg/mL, respectively.     

Establishment of an HPLC method for testing acetylcholinesterase inhibitory activity and compared with traditional spectrophotometry

Acetylcholinesterase (AChE) inhibitory activity test is one of the important areas of natural product research, which is traditionally tested by spectrophotometry. In this work, a simple high-performance liquid chromatography (HPLC) method was developed for testing AChE inhibitory activity in several natural products. Using galanthamine hydrobromide and huperzine A as positive controls, it was found that the optimal conditions for sample preparation are 7.0–8.0 for pH, 30 min for reaction time, 37 °C for reaction temperature, 1.1 × 10^?3 U mL^?1 for concentration of AChE, and 0.625 mM for acetylthiocholine iodide in the final reaction mixture with total volume 2 mL. The Diamonsil C₁₈ column was used and the chromatographic conditions were mobile phase methanol–water–triethylamine (40:60:0.05, v/v/v), flow rate 1.0 mL min^?1, injection volume 5 μL, run time 5 min, column temperature 37 °C, and wavelength 405 nm. The AChE inhibitory activity of anthocyanin with concentration of 10, 20, and 50 μg mL^?1, blueberry extract and purple potato extract with concentration of 20, 100, and 500 μg mL^?1 were further determined under this conditions. The results showed the inhibition ratios obtained from spectrophotometry were nearly adjacent and approximately lower than 10% and the values of absorbance mostly exceed 0.8, but the absorbance should ensure in the range of 0.15–0.8 to guarantee smaller relative error for spectrophotometry. While the inhibition ratios gained from HPLC method were higher than 20% and had greater difference, they had better comparability to the different concentrations of anthocyanin and its extracts. It is revealed that the HPLC method can be used for the evaluation of the AChE inhibitory activity in natural product extracts with deep color or not.     

Chemical constituents of essential oil of endemic Rhanterium suaveolens Desf. growing in Algerian Sahara with antibiofilm,antioxidant and anticholinesterase activities

Twenty compounds were detected in the essential oil of Rhanterium suaveolens representing 98.01% of the total oil content. Perillaldehyde (45.79%), caryophyllene oxide (24.82%) and β-cadinol (5.61%) were identified as the main constituents. In β-carotene–linoleic acid assay, both the oil and the methanol extract exhibited good lipid peroxidation inhibition activity, with IC₅₀ values of 17.97 ± 5.40 and 11.55 ± 3.39 μg/mL, respectively. In DPPH and CUPRAC assays, however, the methanol extract exhibited a good antioxidant activity. The highest antibiofilm activity has been found 50.30% against Staphylococcus epidermidis (MU 30) at 20 μg/mL for essential oil and 58.34% against Micrococcus luteus (NRRL B-4375) at 25 mg/mL concentration for methanol extract. The in vitro anticholinesterase activity of methanol extract showed a moderate acetylcholinesterase inhibitory (IC₅₀ = 168.76 ± 0.62 μg/mL) and good butyrylcholinesterase inhibitory (IC₅₀ = 54.79 ± 1.89 μg/mL) activities. The essential oil was inactive against both enzymes.     

Acanthus mollis L. leaves as source of anti-inflammatory and antioxidant phytoconstituents

This work expands the phytochemical composition knowledge of Acanthus mollis and evaluates antioxidant and anti-inflammatory activities which could be related with its traditional uses. Extracts from leaves, obtained by sequential extraction, were screened using TLC and HPLC-PDA. The ethanol extract was the most active on DPPH assay (IC₅₀ = 20.50 μg/mL) and inhibited nitric oxide (NO) production in RAW 264.7 macrophages (IC₅₀ = 48.31 μg/mL). Significant amounts of cyclic hydroxamic and phenolic acids derivatives were detected. A lower antioxidant effect was verified for a fraction enriched with DIBOA derivatives (IC₅₀ = 163.02 μg/mL), suggesting a higher contribution of phenolic compounds for this activity in ethanol extract. However, this fraction exhibited a higher inhibition of NO production (IC₅₀ = 32.32 μg/mL), with absence of cytotoxicity. These results support the ethnomedical uses of this plant for diseases based on inflammatory processes. To our knowledge, it is the first report to the anti-inflammatory activity for DIBOA derivatives.     

Experimental and computational approaches to reveal the potential of Ficus deltoidea leaves extract as α-amylase inhibitor

Ficus deltoidea leaves extract are known to have good therapeutic properties such as antioxidant, anti-inflammatory and anti-diabetic. We showed that 50% ethanol-water extract of F. deltoidea leaves and its pungent compounds vitexin and isovitexin exhibited significant (p < 0.05) α-amylase inhibition with IC₅₀ (vitexin: 4.6 μM [0.02 μg/mL]; isovitexin: 0.06 μg/mL [13.8 μM] and DPPH scavenging with IC₅₀ (vitexin: 92.5 μM [0.4 μg/mL]; isovitexin: 0.5 μg/mL [115.4 μM]). Additionally, molecular docking analysis confirmed that vitexin has a higher binding affinity (-7.54 kcal/mol) towards α-amylase compared to isovitexin (?5.61 kcal/mol). On the other hand, the molecular dynamics findings showed that vitexin-α-amylase complex is more stable during the simulation of 20 ns when compared to the isovitexin-α-amylase complex. Our results suggest that vitexin is more potent and stable against α-amylase enzyme, thus it could develop as a therapeutic drug for the treatment of diabetes.     

Ruta chalepensis L. (Rutaceae) leaf extract: chemical composition,antioxidant and hypoglicaemic activities

Ruta chalepensis L. (Rutaceae) leaf extract was investigated for its chemical profile and antioxidant and hypoglycaemic properties. The antioxidant effects were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), β-carotene bleaching, and metal chelating activity assays. The carbohydrate-hydrolysing enzymes inhibition assay was used to test the hypoglycaemic potential. R. chalepensis showed a high content of hesperidin and rutin with values of 591.9 and 266.7 mg/g dry extract, respectively. The extract exhibited a promising protection of lipid peroxidation (IC₅₀ value of 16.9 μg/mL) and inhibited both α-amylase and α-glucosidase enzymes in a concentration-dependent manner. The highest activity was found against α-amylase (IC₅₀ value of 69.0 μg/mL). The obtained results support the use of R. chalepensis leaves as healthy food ingredients.