Biosynthesis, Characterization, and Biological Activities of Procyanidin Capped Silver Nanoparticles

In this study, procyanidin dimers and Leucosidea sericea total extract (LSTE) were employed in the synthesis of silver nanoparticles (AgNPs) and characterized by ultraviolet-visible (UV-Visible) spectroscopy, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), and dynamic light scattering (DLS) techniques. AgNPs of about 2–7 nm were obtained. DLS and stability evaluations confirmed that the AgNPs/procyanidins conjugates were stable. The formed nanoparticles exhibited good inhibitory activities against the two enzymes studied. The IC50 values against the amylase enzyme were 14.92 ± 1.0, 13.24 ± 0.2, and 19.13 ± 0.8 µg/mL for AgNPs coordinated with LSTE, F1, and F2, respectively. The corresponding values for the glucosidase enzyme were 21.48 ± 0.9, 18.76 ± 1.0, and 8.75 ± 0.7 µg/mL. The antioxidant activities were comparable to those of the intact fractions. The AgNPs also demonstrated bacterial inhibitory activities against six bacterial species. While the minimum inhibitory concentrations (MIC) of F1-AgNPs against Pseudomonas aeruginosa and Staphylococcus aureus were 31.25 and 15.63 µg/mL respectively, those of LSTE-AgNPs and F2-AgNPs against these organisms were both 62.50 µg/mL. The F1-AgNPs demonstrated a better bactericidal effect and may be useful in food packaging. This research also showed the involvement of the procyanidins as reducing and capping agents in the formation of stable AgNPs with potential biological applications.

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Bioactivity-Guided Isolation of Phytochemicals from Vaccinium dunalianum Wight and Their Antioxidant and Enzyme Inhibitory Activities

Molecules ◽

10.3390/molecules26072075 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2075

Author(s):

Tianrui Zhao ◽

Mengxue Sun ◽

Lingpeng Kong ◽

Qingwang Xue ◽

Yudan Wang ◽

...

Keyword(s):

Pancreatic Lipase ◽

Antioxidant Activities ◽

Bioactive Components ◽

Inhibitory Effects ◽

Macroporous Resin ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Ic50 Values ◽

Trolox Equivalent ◽

Inhibitory Activities

Vaccinium dunalianum Wight, usually processed as a traditional folk tea beverage, is widely distributed in the southwest of China. The present study aimed to investigate the antioxidant, α-glucosidase and pancreatic lipase inhibitory activities of V.dunalianum extract and isolate the bioactive components. In this study, the crude extract (CE) from the buds of V. dunalianum was prepared by the ultrasound-assisted extraction method in 70% methanol and then purified with macroporous resin D101 to obtain the purified extract (PM). Five fractions (Fr. A–E) were further obtained by MPLC column (RP-C18). Bioactivity assays revealed that Fr. B with 40% methanol and Fr. D with 80% methanol had better antioxidant with 0.48 ± 0.03 and 0.62 ± 0.01 nM Trolox equivalent (TE)/mg extract for DPPH, 0.87 ± 0.02 and 1.58 ± 0.02 nM TE/mg extract for FRAP, 14.42 ± 0.41 and 19.25 ± 0.23 nM TE/mg extract for ABTS, and enzyme inhibitory effects with IC50 values of 95.21 ± 2.21 and 74.55 ± 3.85 for α-glucosidase, and 142.53 ± 11.45 and 128.76 ± 13.85 µg/mL for pancreatic lipase. Multivariate analysis indicated that the TPC and TFC were positively related to the antioxidant activities. Further phytochemical purification led to the isolation of ten compounds (1–10). 6-O-Caffeoylarbutin (7) showed significant inhibitory effects on α-glucosidase and pancreatic lipase enzymes with values of 38.38 ± 1.84 and 97.56 ± 7.53 µg/mL, and had the highest antioxidant capacity compared to the other compounds.

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Characterization of Epigallocatechin-Gallate-Grafted Chitosan Nanoparticles and Evaluation of Their Antibacterial and Antioxidant Potential

Polymers ◽

10.3390/polym13091375 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1375

Author(s):

María J. Moreno-Vásquez ◽

Maribel Plascencia-Jatomea ◽

Saúl Sánchez-Valdes ◽

Judith C. Tanori-Córdova ◽

Francisco J. Castillo-Yañez ◽

...

Keyword(s):

Biomedical Applications ◽

Food Packaging ◽

Inhibitory Concentration ◽

Antioxidant Activities ◽

Bacterial Species ◽

Chitosan Nanoparticles ◽

Epigallocatechin Gallate ◽

Antioxidant Power ◽

Ferric Reducing Antioxidant Power

Nanoparticles based on chitosan modified with epigallocatechin gallate (EGCG) were synthetized by nanoprecipitation (EGCG-g-chitosan-P). Chitosan was modified by free-radical-induced grafting, which was verified by Fourier transform infrared (FTIR). Furthermore, the morphology, particle size, polydispersity index, and zeta potential of the nanoparticles were investigated. The grafting degree of EGCG, reactive oxygen species (ROS) production, antibacterial and antioxidant activities of EGCG-g-chitosan-P were evaluated and compared with those of pure EGCG and chitosan nanoparticles (Chitosan-P). FTIR results confirmed the modification of the chitosan with EGCG. The EGCG-g-chitosan-P showed spherical shapes and smoother surfaces than those of Chitosan-P. EGCG content of the grafted chitosan nanoparticles was 330 μg/g. Minimal inhibitory concentration (MIC) of EGCG-g-chitosan-P (15.6 μg/mL) was lower than Chitosan-P (31.2 μg/mL) and EGCG (500 μg/mL) against Pseudomonas fluorescens (p < 0.05). Additionally, EGCG-g-chitosan-P and Chitosan-P presented higher Staphylococcus aureus growth inhibition (100%) than EGCG at the lowest concentration tested. The nanoparticles produced an increase of ROS (p < 0.05) in both bacterial species assayed. Furthermore, EGCG-g-chitosan-P exhibited higher antioxidant activity than that of Chitosan-P (p < 0.05) in 2,2′-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and ferric-reducing antioxidant power assays. Based on the above results, EGCG-g-chitosan-P shows the potential for food packaging and biomedical applications.

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Antioxidant and cytotoxic studies of Acacia nilotica twig extract and their green synthesized silver nanoparticles

Letters in Applied NanoBioScience ◽

10.33263/lianbs92.975980 ◽

2020 ◽

Vol 9 (2) ◽

pp. 975-980 ◽

Cited By ~ 1

Keyword(s):

Antioxidant Activity ◽

Silver Nanoparticles ◽

Cell Lines ◽

Antioxidant Activities ◽

Reducing Power ◽

Acacia Nilotica ◽

Total Phenolic ◽

Hek 293 ◽

Selected Area Electron Diffraction ◽

Wide Range

Acacia nilotica (L.) Delile is well known as “Desi Kikar”or Babul in India that possesses a wide range of pharmacological activities. In the present study, Acacia nilotica twig extract and its synthesized silver nanoparticles (AgNPs) were evaluated for total phenolic content (TPC), antioxidant activity and cytotoxic effects. Characterization of AgNPs was done by UV-Visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and Selected area electron diffraction (SAED) techniques. Antioxidant potential was determined using different assays including 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power and β-carotene linoleic acid. Cytotoxicity was tested by 3-(4,5-dimethyl-2-yl)-2,5-diphynyl tetrazolium bromide (MTT) assay on Human embryonic kidney (HEK)-293 cell lines. The results indicated that AgNPs exhibited higher antioxidant activity (81.11 %) and TPC (57.35 mg of GAE/mL of extract) as compare to plant extract. A positive correlation was observed between the TPC and antioxidant activities. The inhibitory concentration (IC50) of A. nilotica extract and AgNPs was 52.08µg/mL and 56.82µg/mL respectively. Cytotoxicity against HEK-293 cell lines was dose dependent. Accordingly, it is summarized that A. nilotica based AgNPs could serve as a potential antioxidant for therapeutic purposes.

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Antibacterial and Antioxidant Activities of Slender Amaranth Weed

Planta Daninha ◽

10.1590/s0100-83582020380100006 ◽

2020 ◽

Vol 38 ◽

Cited By ~ 1

Author(s):

M. AKBAR ◽

I.N. SHERAZI ◽

M.S. IQBAL ◽

T. KHALIL ◽

H.M. WAQAS

Keyword(s):

Antioxidant Activity ◽

Antibacterial Activity ◽

Ethyl Acetate ◽

Pseudomonas Syringae ◽

Antioxidant Activities ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Bacterial Species ◽

Radical Scavenging ◽

Root Extract

ABSTRACT: In the present study, antibacterial and antioxidant [1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity] activities of a weed, slender amaranth (Amaranthus viridis L.) were investigated. Extracts of different plant parts were prepared in n-hexane, chloroform and ethyl acetate. Antibacterial activity was measured by using 100 mg mL-1 concentration extracts against 4 deadly phytopathogenic bacterial species viz. Pseudomonas syringae Van Hall, Ralstonia solanacearum Smith, Erwinia carotovora (Jones), Holland and Xanthomonas axonopodis Hasse. In antioxidants assays, 10, 20 and 30 mg mL-1 extracts were used keeping DPPH as control. In these bioassays, ethyl acetate fraction of A. viridis leaf exhibited the best antibacterial and antioxidants activity. Ethyl acetate leaf fraction showed the highest inhibition zone diameter (IZD) where it caused 21 mm IZD against P. syringae and 19 mm IZD against E. carotovora. This extract also showed 22, 52 and 84% antioxidant activity at 10, 20 and 30 mg mL-1 concentrations, respectively. Previously there is no report available that describes antibacterial activity of root extract of A. viridis against P. syringae. Moreover, antioxidant activity of stem and root extracts in n-hexane, chloroform and ethyl acetate was investigated first time in the world. It was concluded that the biological activities observed during the present investigation may be due to the presence of bioactive constituents that can be harnessed as natural antibacterials and antioxidants.

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Phenolic compounds and biological activities of rye (Secale cereale L.) grains

Open Chemistry ◽

10.1515/chem-2019-0103 ◽

2019 ◽

Vol 17 (1) ◽

pp. 988-999 ◽

Cited By ~ 2

Author(s):

Katarína Kulichová ◽

Jozef Sokol ◽

Peter Nemeček ◽

Mária Maliarová ◽

Tibor Maliar ◽

...

Keyword(s):

Secale Cereale ◽

High Performance ◽

Antioxidant Activities ◽

Biological Activities ◽

Antioxidant Properties ◽

Biologically Active ◽

Spectrophotometric Methods ◽

Secale Cereale L ◽

Inhibitory Activities ◽

Traditional Bread

AbstractThe rye flour is, together with the wheat flour, the basic ingredient used in traditional bread baking. The rye grain contains many compounds with significant impacts on the consumer. Considering that, various biologically active phytochemicals were determined in extracts from mature grains of 19 rye genotypes (Secale cereale L.). The content of total phenols, flavonoids, phenolic acids and thiols, as well as antioxidant activities and inhibitory activities against trypsin, thrombin, and urokinase were analyzed by spectrophotometric methods. The vanillic acid, vanillin, p-coumaric acid, and t-ferulic acid were analyzed in particular by high performance liquid chromatography (HPLC). The observed differences in the amounts and activities between rye genotypes reflected variations in their genetic background. Rye grain is a remarkable source of specific phytochemicals. Genetic diversity in rye makes it possible to identify individual genotypes that have a unique content and biological activity of compounds deposited in mature grains. One subgroup of rye genotypes had higher values of antioxidant properties and concentrations of polyphenols. Other sub-group had higher proteinase inhibitory activities and contents of polyphenols. The third sub-group contained as though the universal genotypes, i.e. genotypes with average values in nearly all the measured parameters.

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Antioxidant, cytotoxic activity and pharmacokinetic studies by SwissAdme, Molinspiration, Osiris and DFT of PhTAD-substituted dihydropyrrole derivatives

Current Computer - Aided Drug Design ◽

10.2174/1573409917666210223105722 ◽

2021 ◽

Vol 17 ◽

Author(s):

Arif Ayar ◽

Masuk Aksahin ◽

Seda Mesci ◽

Burak Yazgan ◽

Melek Gül ◽

...

Keyword(s):

Cytotoxic Activity ◽

Cell Lines ◽

Heterocyclic Compounds ◽

Antioxidant Activities ◽

Biological Activities ◽

Molecular Structures ◽

Biologically Active ◽

Pharmacokinetic Studies ◽

Ic50 Values ◽

Mcf 7

Background: Pyrrole compounds having a heterocyclic structure are the most researched and biological activities such as antioxidant and anticancer. Objective: Herein is a first effort to study the significance of heterocyclic compounds to include pyrrole and triazolidine-3,5-dion moiety, on the pharmacokinetic, antioxidant activity and cytotoxic activity on MCF-7 and MCF-12A cell lines. Method: The molecular structures of compounds I-XIV were simulated by the theoretical B3LYP/DFT method. Pharmacokinetic studies of PhTAD-substituted heterocyclic compounds (I-XIV) were analyzed to show Lipinski's rules via in-silico methods of Swiss-ADME. The drug likeness calculations were carried out Molinspiration analyses. The some toxicity risk parameter can be quantified using Osiris. Antioxidant activities determined by DPPH, Fe+2 ions chelating and reducing. Cytotoxic activity measured by MTT and RTCA. Results: Compared with the DPPH activity, the metal chelating activity exhibited serious similar antioxidant effects by PhTAD substituted pyrrole compounds. The same compounds showed the highest activity among the two antioxidant activities. The IC50 values of the compounds are in the range of 12 and 290 µM in MCF-7 cell line. In the MTT and RTCA assays, All compounds showed cytotoxic activity, but about half of the fourteen compounds showed high cytotoxicity. IC50 values of the compounds are in the range of 5 and 54 µM for MTT and range of 1.5 and 44 µM for RTCA. Conclusion: Data of the antioxidant and cytotoxic activity of PhTAD-substituted dihydropyrrole-derived compounds in MCF-7 and MCF-12A cell lines confirmed that the compounds are a biologically active compound and is notable for anti-cancer researches.

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Extraction of flavonoids in pomelos’ peels using Box-Behnken response surface design and their biological activities

Vietnam Journal of Science Technology and Engineering ◽

10.31276/vjste.63(2).52-57 ◽

2021 ◽

Vol 63 (2) ◽

pp. 52-57

Author(s):

Truong Ngoc Quynh Phuong ◽

◽

Pham Van Hung ◽

Nguyen Thi Lan Phi ◽

◽

...

Keyword(s):

Response Surface ◽

Antioxidant Activities ◽

Biological Activities ◽

Solvent Ratio ◽

Optimum Conditions ◽

Flavonoid Content ◽

Surface Design ◽

Pomelo Peel ◽

Order Polynomial ◽

Ic50 Values

The objectives of this study were to optimize the extraction conditions of flavonoids from the pomelo peel using the Box-Behnken response surface methodology and to investigate the chemical composition and biological activities of the extracts from three different pomelo species under optimized extraction conditions. Three extraction condition factors of were varied, including the solid-solvent ratio (1/15-1/45 g/ml), temperature (30-60oC), and time (20-60 min), which affected the efficiency of the total flavonoid content (TFC). The high R2 coefficient of 0.93 indicated that the experimental data obtained in this study fit well to a second-order polynomial using multiple regression analysis. The maximum TFC extracted from the pomelo peel was 6.0 mg/g (dried basis, db), which was obtained using Derringer’s desired function methodology under the following optimum conditions: a solid-solvent ratio of 1/44 g/ml, temperature of 30.7oC, and time of 34.6 min. The results also indicated that the Tan Trieu pomelo peel had the highest TFC and naringin concentration followed by the Nam Roi and Duong Hong pomelo peels, whereas the Nam Roi pomelo peel had a higher hesperidin concentration than the others. The extracts of the pomelo peels exhibited strong antioxidant activities with low IC50 values. However, these extracts showed only a slight effect on cancer cells, including lung cancer and breast cancer, when tested at 100 μg/ml.

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Bioactive Phytochemical Compounds of Physalis minima L. and its Anticholinesterase and Antioxidant Activities

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23067 ◽

2021 ◽

Vol 33 (4) ◽

pp. 741-746

Author(s):

V. PRABHU ◽

K. ARUNKUMAR ◽

B. MONIKA ◽

V. LATHA ◽

G. SIBI

Keyword(s):

Antioxidant Activities ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Acetylcholine Esterase ◽

Esterase Inhibition ◽

Acetylthiocholine Iodide ◽

Ic50 Values ◽

Phytochemical Compounds

Physalis minima Linn. was investigated for its antioxidant and acetylcholine esterase inhibition activities. The methanolic extract of the whole plant was evaluated for radical scavenging and in vitro hydrolysis of acetylthiocholine iodide. Inhibitory concentration (IC50) of the extract exhibited IC50 values of 78.6, 46.2, 76.7 and 296 μg/mL under 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS (2,2′-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid)), hydroxyl radical scavenging and acetylcholine esterase inhibition assays. GC-MS analysis revealed the presence of 11 compounds of which most of the compounds were reported with biological activities. The study suggests further investigations of P. minima for isolation, purification and characterization of valuable bioactive compounds related to their radical scavenging activity and for the treatment of neurodegenerative disease.

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Chemical Compounds, Antioxidant Activities, and Inhibitory Activities Against Xanthine Oxidase of the Essential Oils From the Three Varieties of Sunflower (Helianthus annuus L.) Receptacles

Frontiers in Nutrition ◽

10.3389/fnut.2021.737157 ◽

2021 ◽

Vol 8 ◽

Author(s):

Xin-Sheng Liu ◽

Bo Gao ◽

Zhan-De Dong ◽

Zi-An Qiao ◽

Min Yan ◽

...

Keyword(s):

Uric Acid ◽

Essential Oils ◽

Xanthine Oxidase ◽

Antioxidant Activities ◽

Biological Activities ◽

Pearson Correlation ◽

Chemical Compounds ◽

Bornyl Acetate ◽

Inhibitory Ability ◽

Inhibitory Activities

Background/Aim: Essential oils of sunflower receptacles (SEOs) have antibacterial and antioxidant potential. However, the differences of biological activities from the different varieties of sunflowers have not been studied till now. The purpose of this study was to compare the differences of chemical compounds, antioxidant activities, and inhibitory activities against xanthine oxidase (XO) of SEOs from the three varieties of sunflowers including LD5009, SH363, and S606.Methods: SEOs were extracted by using the optimal extraction conditions selected by response surface methodology (RSM). Chemical compounds of SEOs were identified from the three varieties of sunflowers by gas chromatography-mass spectrometry (GC-MS). Antioxidant activities of SEOs were detected by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and iron ion reduction ability. Inhibitory activities of SEOs against XO were measured by using UV spectrophotometer. XO inhibitors were selected from the main chemical compounds of SEOs by the high-throughput selections and molecular simulation docking.Results: The extraction yields of SEOs from LD5009, SH363, and S606 were 0.176, 0.319, and 0.580%, respectively. A total of 101 chemical compounds of SEOs were identified from the three varieties of sunflowers. In addition, the results of inhibitory activities against XO showed that SEOs can reduce uric acid significantly. Eupatoriochromene may be the most important chemical compounds of SEOs for reducing uric acid. The results of antioxidant activities and inhibitory activities against XO showed that SEOs of LD5009 had the strongest antioxidant and XO inhibitory activities. The Pearson correlation coefficient (r > 0.95) showed that γ-terpinene, (E)-citral, and L-Bornyl acetate were highly correlated with the antioxidant activities and XO inhibitory ability.Conclusion: SEOs had antioxidant activities and XO inhibitory ability. It would provide more scientific information for utilization and selection of varieties of sunflowers, which would increase the food quality of sunflowers and incomes of farmers.

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Compositional Analysis and Antioxidant Activities of Thymus pubescens Essential Oil from Iran

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666201230091042 ◽

2020 ◽

Vol 23 ◽

Author(s):

Bahman Nickavar ◽

Elaheh Malekitabar

Keyword(s):

Chemical Composition ◽

Essential Oil ◽

Antioxidant Activities ◽

Biological Activities ◽

Compositional Analysis ◽

Detection And Identification ◽

Ic50 Values ◽

Main Components ◽

Β Carotene

Background: The genus Thymus is one of the well-known members of the Lamiaceae, which comprises about 215 species. It is a polymorphic genus in this family. Therefore, possible differences in chemical composition among polymorphs may result in differences in their biological activities. Objective: This study was designed to specify chemical composition in order to assess antioxidant activities and to characterize active constituents of essential oil from Thymus pubescens. Methods: Essential oil was collected by hydrodistillation and was analyzed using GC-MS and GC-FID. Antioxidant activities were evaluated by ABTS radical cation scavenging and β-carotene bleaching inhibition methods. Detection and identification of antioxidant components were performed by TLC-bioautography assay using ABTS•+ reagent. Results: GC analyses indicated the presence of 39 components, accounting for 96.64% of total constituents, with thymol (38.67%), γ-terpinene (7.46%), and p-cymene (5.54%) as the main components. The IC50 values for antioxidant activities were equal to 1.15 (1.05 – 1.25) μg/mL and 0.45 (0.33 – 0.62) μg/mL for ABTS•+ scavenging and β-carotene bleaching inhibition tests, respectively. TLC-bioautograpgy of oil resulted in identification of thymol as the major antioxidant compound. Conclusion: Essential oil exhibited very potent and significant antioxidant activities correlated well with increasing dose in vitro.

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