Identification and quantification of major derivatives of ellagic acid and antioxidant properties of thinning and ripe Spanish pomegranates

Avocado has become fashionable due to its great organoleptic and nutritional properties. It is consumed as a fresh product and it is also processed to obtain salad oil and guacamole. In all cases, the only usable portion is the pulp. Therefore, to be a more sustainable and profitable agribusiness, it is important to recognize which compounds from the peel and the stone waste can be converted into valuable bio-products. Therefore, their chemical composition was determined according to the National Renewable Energy Laboratory, the total phenolic content by the Folin-Ciocalteu method and the antioxidant properties by the FRAP and TEAC assays. The main components of the peel and stone were acid-insoluble lignin (35.0% and 15.3%, respectively), polymeric sugars (23.6% and 43.9%, respectively), and the aqueous extractives (15.5% and 16.9%, respectively). Both biomasses contain lipids and protein, but a minor proportion (<6%). The valorization of lignin and sugars is of interest given the high content; stones are a rich source of glucose (93.2% of the polymeric fraction), which could be used to obtain biofuels or derivatives of interest. The extractive fraction of the peel contained the highest number of phenolic compounds (4.7 g/100 g biomass), mainly concentrated in the aqueous fraction (i.e., 87%) compared to the ethanol one, which was subsequently extracted. It correlated with major antioxidant activity and, therefore, the peel can be applied to obtain antioxidants and water can be used as an environmentally friendly extraction solvent.

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Cytotoxic and antioxidant potentials of ellagic acid derivatives from Conocarpus lancifolius (Combretaceae)

Tropical Journal of Pharmaceutical Research ◽

10.4314/tjpr.v19i5.24 ◽

2020 ◽

Vol 19 (5) ◽

pp. 1037-1080

Author(s):

Malik Saadullah ◽

Muhammad Asif ◽

Abdul Sattar ◽

Kanwal Rehman ◽

Shahid Shah ◽

...

Keyword(s):

Ellagic Acid ◽

Antioxidant Properties ◽

Human Colon ◽

Antioxidant Compounds ◽

Phytochemical Analysis ◽

Human Colon Cancer ◽

Chemical Structures ◽

Ellagic Acid Derivatives ◽

Layer Chromatography

Purpose: Isolation, characterisation and structure elucidation of compounds obtained from Conocarpus lancifolius and screening of their pharmacological effects in vitro.Methods: After collection, authentication and extraction from whole C. lancifolius plants, screening for secondary metabolites, thin-layer chromatography and subsequent open column chromatography were performed for phytochemical analysis and subsequent purification of the compounds. The chemical structures of the isolated compounds were elucidated using spectroscopic (UV-visible, infrared and mass) spectroscopy, and nuclear magnetic resonance (1H-NMR, 13C-NMR including BB, DEPT-135, 90 and two-dimensional correlation techniques, including HMBC and HSQC). The cytotoxic and antioxidant potentials of extracts and compounds obtained from C. lancifolius were evaluated using in vitro models.Results: Two ellagic acid derivatives, 2,3,8-tri-o-methylellagic acid (A) and 3-O-methylellagic acid 4-O-β-D-glucopyranoside (B), were isolated. Both compounds (A and B) were cytotoxic in a variety of cancer cell lines, including murine lymphocytic leukaemia (P-388, half-maximal inhibitory concentration (IC50) =3.60 and 2.40 μg/mL, respectively), human colon cancer (Col-2, IC50 = 0.76 and 0.92 μg/mL, respectively) and human breast cancer (MCF-7, IC50 = 0.65 and 0.54 μg/mL, respectively). Moreover, both compounds showed significant antioxidant potential in vitro.Conclusion: C. lancifolius extract and isolated ellagic acid derivatives (compounds A and B) possess cytotoxic and antioxidant properties. These findings suggest that C. lancifolius contains bioactive compounds that can be potentially developed as natural cytotoxic and antioxidant compounds. Keywords: Conocarpus lancifolius, Ellagic acid, Combretaceae, Cytotoxic activity, Antioxidant

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Ellagic Acid May Improve Mechanical and Barrier Properties in Films of Starch-A Review Paper

Journal of Food Research ◽

10.5539/jfr.v5n3p61 ◽

2016 ◽

Vol 5 (3) ◽

pp. 61

Author(s):

J. M. Tirado-Gallegos ◽

D. R. Sepúlveda-Ahumada ◽

P. B. Zamudio-Flores ◽

M. L. Rodríguez-Marin ◽

Francisco Hernández-Centeno ◽

...

Keyword(s):

Ellagic Acid ◽

Structural Changes ◽

Antioxidant Properties ◽

Barrier Properties ◽

Packaging Materials ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Film Forming ◽

Starch Films

<p>Packaging increases the shelf life of food and facilitates its handling, transportation and marketing. The main packaging materials are plastics derived from petroleum, but their accumulation has given rise to environmental problems. An alternative is the use of biodegradable materials. In this regard, starch is an excellent choice because it is an abundant and renewable source with film-forming properties. However, the films obtained from starch have some limitations with respect to their mechanical and barrier properties. Several strategies have been developed in order to improve these limitations, ranging from the addition of lipids to the modification of the polymer structure. The aim of this review was propose the use of ellagic acid as a cross-linking agent that may improves the mechanical and barrier properties in films based on exists reports that phenolic compounds interact with starch-based materials decreasing their rate of retrogradation. Furthermore, ellagic acid is a powerful natural antioxidant, which would allow the production of active packaging with antioxidant properties, in addition to the improvement of the mechanical and barrier properties of starch films. In this concern more studies such as Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis are necessary to verify the structural changes and interactions between starch and ellagic acid. We expect extensive use of it in the future of packaging materials.</p>

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Suppression of Methane Generation during Methanogenesis by Chemically Modified Humic Compounds

Antioxidants ◽

10.3390/antiox9111140 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1140

Author(s):

Elena Efremenko ◽

Olga Senko ◽

Nikolay Stepanov ◽

Nikita Mareev ◽

Alexander Volikov ◽

...

Keyword(s):

Antioxidant Properties ◽

Nutrient Media ◽

Potassium Humate ◽

Methane Generation ◽

Chemically Modified ◽

Humic Compounds ◽

Negative Effect ◽

The Media ◽

First Time ◽

Derivatives Of

The introduction of various concentrations of chemically modified humic compounds (HC) with different redox characteristics into the media with free and immobilized anaerobic consortia accumulating landfill gases was studied as approach to their functioning management. For this purpose, quinone (hydroquinone, naphthoquinone or methylhydroquinone) derivatives of HC were synthesized, which made it possible to vary the redox and antioxidant properties of HC as terminal electron acceptors in methanogenic systems. The highest acceptor properties were obtained with potassium humate modified by naphthoquinone. To control possible negative effect of HC on the cells of natural methanogenic consortia, different bioluminescent analytical methods were used. The addition of HC derivatives, enriched with quinonones, to nutrient media at concentrations above 1 g/L decreased the energetic status of cells and the efficiency of the methanogenesis. For the first time, the significant decrease in accumulation of biogas was reached as effect of synthetic HC derivatives, whereas both notable change of biogas composition towards increase in the CO2 content and decrease in CH4 were revealed. Thus, modification with quinones makes it possible to obtain low-potential HC derivatives with strongly pronounced acceptor properties, promising for inhibition of biogas synthesis by methanogenic communities.

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Improvement of endothelial function by Gunnera tinctoria extract with antioxidant properties

Biological Research ◽

10.1186/s40659-020-00322-2 ◽

2020 ◽

Vol 53 (1) ◽

Author(s):

Constanza Sabando ◽

Maité Rodríguez-Díaz ◽

Walther Ide ◽

Edgar Pastene ◽

Marcia Avello ◽

...

Keyword(s):

Oxidative Stress ◽

Endothelial Function ◽

Ellagic Acid ◽

Methanolic Extract ◽

Umbilical Vein ◽

Chemical Constituents ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Antioxidant Power ◽

Quercetin Derivatives

Abstract Background Gunnera tinctoria has been collected by Mapuche-Pewenche people for food and medicinal purposes. The high polyphenol content of methanolic extract from G. tinctoria leaves with chemical constituents such as ellagic acid and quercetin derivatives suggests its application to prevent endothelial dysfunction and oxidative stress. The aim of this study was to provide evidence of the protective effect of this extract on endothelial function by reducing oxidative stress induced by high d-glucose and H2O2, as well as by stimulating nitric oxide (NO) levels in human umbilical vein endothelial cells (HUVECs). Results A methanolic extract with a high content of polyphenols (520 ± 30 mg gallic acid equivalents/g dry extract) was obtained from G. tinctoria leaves. Its main constituent was ellagic acid. The results of Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays of the extract confirmed its antioxidant activity by inhibition pathway of radical species. The incubation of HUVECs with the extract decreased the apoptosis and reactive oxygen species (ROS) synthesis induced by high extracellular concentration of d-glucose or hydrogen peroxide. The extract increased endothelial NO levels and reduced vasoconstriction in human placental vessels. Conclusions This study provides evidence about the antioxidant and endothelial protective properties of methanolic G. tinctoria leaf extract. The extract improves the availability of NO in HUVECs, inhibiting the production of ROS and vasoconstriction.

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Antioxidant Properties of Select Radiation Mitigators Based on Semicarbazone and Pyrazole Derivatives of Curcumin

Oxygen Transport to Tissue XXXII - Advances in Experimental Medicine and Biology ◽

10.1007/978-1-4419-7756-4_39 ◽

2011 ◽

pp. 291-297 ◽

Cited By ~ 4

Author(s):

Steven G. Swarts ◽

Mei Zhang ◽

Liangjie Yin ◽

Chaomei Liu ◽

Yeping Tian ◽

...

Keyword(s):

Antioxidant Properties ◽

Pyrazole Derivatives ◽

Derivatives Of

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Regioselective Lipase-Catalyzed Synthesis of 3-O-Acyl Derivatives of Resveratrol and Study of Their Antioxidant Properties

Journal of Agricultural and Food Chemistry ◽

10.1021/jf903210q ◽

2010 ◽

Vol 58 (2) ◽

pp. 807-813 ◽

Cited By ~ 46

Author(s):

Pamela Torres ◽

Ana Poveda ◽

Jesús Jimenez-Barbero ◽

Antonio Ballesteros ◽

Francisco J. Plou

Keyword(s):

Antioxidant Properties ◽

Derivatives Of ◽

Acyl Derivatives

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Antioxidant properties of 4-vinyl derivatives of hydroxycinnamic acids

Food Chemistry ◽

10.1016/j.foodchem.2011.02.077 ◽

2011 ◽

Vol 128 (1) ◽

pp. 62-69 ◽

Cited By ~ 77

Author(s):

Petra Terpinc ◽

Tomaž Polak ◽

Nataša Šegatin ◽

Andrej Hanzlowsky ◽

Nataša Poklar Ulrih ◽

...

Keyword(s):

Antioxidant Properties ◽

Hydroxycinnamic Acids ◽

Vinyl Derivatives ◽

Derivatives Of

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An efficient synthesis and antioxidant properties of novel imino and amino derivatives of 4-hydroxy coumarins

Archives of Pharmacal Research ◽

10.1007/s12272-010-2220-z ◽

2010 ◽

Vol 33 (1) ◽

pp. 5-15 ◽

Cited By ~ 29

Author(s):

Nenad Vukovic ◽

Slobodan Sukdolak ◽

Slavica Solujic ◽

Neda Niciforovic

Keyword(s):

Antioxidant Properties ◽

Efficient Synthesis ◽

Amino Derivatives ◽

Derivatives Of

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New Accelerators for Vulcanization of Rubber—Part III: Synthesis, Characterization, and Evaluation of Some 2-Mercaptobenzimidazole Derivatives

Rubber Chemistry and Technology ◽

10.5254/1.3536088 ◽

1985 ◽

Vol 58 (4) ◽

pp. 713-727 ◽

Cited By ~ 2

Author(s):

D. Pal ◽

A. Khamrai ◽

B. Adhikari ◽

T. Dutta ◽

Mrinal M. Maiti ◽

...

Keyword(s):

Natural Rubber ◽

Antioxidant Properties ◽

Antioxidant Compounds ◽

Dual Function ◽

Cure Characteristics ◽

Aging Resistance ◽

Rubber Part ◽

Derivatives Of ◽

Better Than

Abstract Five derivatives of 2-mercaptobenzimidazole containing S—N bonds have been synthesized and evaluated for their action as accelerator-antioxidant in NR gum stocks. All these compounds exhibit varying degree of accelerating efficiency; some of them, viz. MBSTP, MBSPT, and MBDSPT, offer excellent cure characteristics and vulcanizate properties comparable to some of the best commercially available curatives such as CPTD. Substitution at the N or S atom of the MB molecule does not affect adversely its antioxidant properties; rather, an improvement in aging resistance has been achieved. The degree and nature of substitution play an important role in the antioxidation properties of these MB derivatives. Thus, disubstitution offers better antioxidation characteristics than monosubstitution, and the latter, in turn, is better than unsubstituted MB. Some discussion on correlation of reactivities of these MB derivatives and their cure synergism with CPTD have been reported. It was observed that these new accelerator—antioxidant compounds show very little cure synergism with CPTD but do show promise as dual-function curatives for natural rubber.

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