Alginate Bioconjugate and Graphene Oxide in Multifunctional Hydrogels for Versatile Biomedical Applications

In this work, we combined electrically-conductive graphene oxide and a sodium alginate-caffeic acid conjugate, acting as a functional element, in an acrylate hydrogel network to obtain multifunctional materials designed to perform multiple tasks in biomedical research. The hybrid material was found to be well tolerated by human fibroblast lung cells (MRC-5) (viability higher than 94%) and able to modify its swelling properties upon application of an external electric field. Release experiments performed using lysozyme as the model drug, showed a pH and electro-responsive behavior, with higher release amounts and rated in physiological vs. acidic pH. Finally, the retainment of the antioxidant properties of caffeic acid upon conjugation and polymerization processes (Trolox equivalent antioxidant capacity values of 1.77 and 1.48, respectively) was used to quench the effect of hydrogen peroxide in a hydrogel-assisted lysozyme crystallization procedure.

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Melatonin deprival modifies follicular and corpus luteal growth dynamics in a sheep model

Reproduction ◽

10.1530/rep-13-0405 ◽

2014 ◽

Vol 147 (6) ◽

pp. 885-895 ◽

Cited By ~ 14

Author(s):

Maria Elena Manca ◽

Maria Lucia Manunta ◽

Antonio Spezzigu ◽

Laura Torres-Rovira ◽

Antonio Gonzalez-Bulnes ◽

...

Keyword(s):

Antioxidant Properties ◽

Growth Dynamics ◽

Oestrous Cycle ◽

Trolox Equivalent Antioxidant Capacity ◽

Corpora Lutea ◽

Sheep Model ◽

Ovarian Status ◽

Trolox Equivalent ◽

And Function ◽

Breeding Seasons

This study assessed the effect of melatonin deprival on ovarian status and function in sheep. Experimental procedures were carried out within two consecutive breeding seasons. Animals were divided into two groups: pinealectomised (n=6) and sham-operated (n=6). The completeness of the pineal gland removal was confirmed by the plasma concentration of melatonin. Ovarian status was monitored by ovarian ultrasonography for 1 year to study reproductive seasonality. Follicular and corpus luteal growth dynamics were assessed during an induced oestrous cycle. As the effects of melatonin on the ovary may also be mediated by its antioxidant properties, plasma Trolox equivalent antioxidant capacity (TEAC) was determined monthly for 1 year. Pinealectomy significantly extended the breeding season (310±24.7 vs 217.5±24.7 days in controls;P<0.05). Both pinealectomised and sham-operated ewes showed a well-defined wave-like pattern of follicle dynamics; however, melatonin deficiency caused fewer waves during the oestrous cycle (4.3±0.2 vs 5.2±0.2;P<0.05), because waves were 1 day longer when compared with the controls (7.2±0.3 vs 6.1±0.3;P<0.05). The mean area of the corpora lutea (105.4±5.9 vs 65.4±5.9 mm2;P<0.05) and plasma progesterone levels (7.1±0.7 vs 4.9±0.6 ng/ml;P<0.05) were significantly higher in sham-operated ewes compared with pinealectomised ewes. In addition, TEAC values were significantly lower in pinealectomised ewes compared with control ones. These data suggest that melatonin, besides exerting its well-known role in the synchronisation of seasonal reproductive fluctuations, influences the growth pattern of the follicles and the steroidogenic capacity of the corpus luteum.Free Italian abstractAn Italian translation of this abstract is freely available athttp://www.reproduction-online.org/content/147/6/885/suppl/DC1.

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Effect of Propofol, Sevoflurane and Desflurane on Systemic Redox Balance

International Journal of Immunopathology and Pharmacology ◽

10.1177/039463200702000316 ◽

2007 ◽

Vol 20 (3) ◽

pp. 585-593 ◽

Cited By ~ 15

Author(s):

G. Cinnella ◽

G. Vendemiale ◽

M. Dambrosio ◽

G. Serviddio ◽

P.L. Pugliese ◽

...

Keyword(s):

Antioxidant Capacity ◽

Antioxidant Properties ◽

Redox Balance ◽

Trolox Equivalent Antioxidant Capacity ◽

Sodium Thiopental ◽

Blood Samples ◽

Plasma Antioxidant Capacity ◽

Trolox Equivalent ◽

Plasma Antioxidant ◽

Group D

We studied the effects of Propofol, Desflurane, and Sevoflurane on the systemic redox balance in patients undergoing laparohysterectomy. We measured blood concentration of glutathione (GSH), plasma antioxidant capacity (Trolox Equivalent Antioxidant Capacity-TEAC), and lipid peroxidation products (malondialdehyde (aMDA) and 4-hydroxynonenal (aHNE) protein adducts). Sixty patients were randomly placed into three groups of twenty people each. In Group P anesthesia was induced with Propofol 2 mg/kg and maintained with 12–10–8 mg/kg/min; in Groups S and D anesthesia was induced with 3 mg/kg Sodium Thiopental and maintained with 2% Sevoflurane and 6% Desflurane, respectively. Blood samples were collected prior to induction (T0bas), 60min and 24h postoperatively (T160' and T224 h). In Group P, GSH increased on T160' (p<0.02) and returned to baseline on T24h, while TEAC remained unmodified; in Groups S, GSH and TEAC decreased on T160' (p<0.01 vs. T0bas, p<0.03 vs. T0bas, respectively); in Group D, on T160' there was a slight decrease of GSH and TEAC. The levels of aMDA slightly decreased throughout the study periods in Group P, increased in Group D, and remained stable in Group S. Propofol showed antioxidant properties, while Sevoflurane and Desflurane seemed to shift the redox balance towards oxidation, yet without inducing overt oxidative damage.

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HPLC, UV-Vis and NMR spectroscopic and DFT characterization of purpurin isolated from Rubia tinctorum L.

Hemijska industrija ◽

10.2298/hemind120419058m ◽

2013 ◽

Vol 67 (1) ◽

pp. 77-88 ◽

Cited By ~ 7

Author(s):

Zoran Markovic ◽

Nedeljko Manojlovic ◽

Svetlana Jeremic ◽

Miroslav Zivic

Keyword(s):

Antioxidant Capacity ◽

Colorimetric Assay ◽

Antioxidant Properties ◽

Electron Delocalization ◽

Trolox Equivalent Antioxidant Capacity ◽

Bond Dissociation Enthalpy ◽

Rubia Tinctorum ◽

Dissociation Enthalpy ◽

Trolox Equivalent

Purpurin (1,2,4-trihidroxyanthraquinone), a naurally occuring anthraquinone pigment present in the root of Rubia tinctorum (Mull. Arg.) Zahlbr. was isolated from the plant, purified and characterized by HPLC chromatography, UV-Vis and NMR spectroscopy. The geometries of the purpurin conformers were optimized using the B3LYP/6-311+G(d,p) level of theory. It was found that all conformations have similar energies and that the corresponding purpurin radicals are planar. In spite of their planarity, there is no significant electron delocalization over the A and C rings. The antioxidant properties of purpurin were investigated using the colorimetric assay as Trolox-equivalent antioxidant capacity, and theoretical BDE (Bond Dissociation Enthalpy). Both methods revealed that purpurin has strong antioxidant capacity.

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Study on the Synthesis, Antioxidant Properties, and Self-Assembly of Carotenoid–Flavonoid Conjugates

Molecules ◽

10.3390/molecules25030636 ◽

2020 ◽

Vol 25 (3) ◽

pp. 636

Author(s):

Ildikó Línzembold ◽

Dalma Czett ◽

Katalin Böddi ◽

Tibor Kurtán ◽

Sándor Balázs Király ◽

...

Keyword(s):

Antioxidant Capacity ◽

Self Assembly ◽

Uv Light ◽

Antioxidant Properties ◽

Hydroxyl Group ◽

Trolox Equivalent Antioxidant Capacity ◽

Solvent Ratio ◽

Protective Effects ◽

Synergistic Enhancement ◽

Trolox Equivalent

Flavonoids and carotenoids possess beneficial physiological effects, such as high antioxidant capacity, anticarcinogenic, immunomodulatory, and anti-inflammatory properties, as well as protective effects against UV light. The covalent coupling of hydrophobic carotenoids with hydrophilic flavonoids, such as daidzein and chrysin, was achieved, resulting in new amphipathic structures. 7-Azidohexyl ethers of daidzein and chrysin were prepared in five steps, and their azide-alkyne [4 + 2] cycloaddition with pentynoates of 8′-apo-β-carotenol, zeaxanthin, and capsanthin afforded carotenoid–flavonoid conjugates. The trolox-equivalent antioxidant capacity against ABTS•+ radical cation and self-assembly of the final products were examined. The 1:1 flavonoid–carotenoid hybrids generally showed higher antioxidant activity than their parent flavonoids but lower than that of the corresponding carotenoids. The diflavonoid hybrids of zeaxanthin and capsanthin, however, were found to exhibit a synergistic enhancement in antioxidant capacities. ECD (electronic circular dichroism) and UV-vis analysis of zeaxanthin–flavonoid conjugates revealed that they form different optically active J-aggregates in acetone/water and tetrahydrofuran/water mixtures depending on the solvent ratio and type of the applied aprotic polar solvent, while the capsanthin derivatives showed no self-assembly. The zeaxanthin bis-triazole conjugates with daidzein and with chrysin, differing only in the position of a phenolic hydroxyl group, showed significantly different aggregation profile upon the addition of water.

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The Effect of an Edible Coating with Tomato Oily Extract on the Physicochemical and Antioxidant Properties of Garambullo (Myrtillocactus geometrizans) Fruits

Agronomy ◽

10.3390/agronomy8110248 ◽

2018 ◽

Vol 8 (11) ◽

pp. 248 ◽

Cited By ~ 8

Author(s):

César López-Palestina ◽

César Aguirre-Mancilla ◽

Juan Raya-Pérez ◽

Juan Ramírez-Pimentel ◽

Jorge Gutiérrez-Tlahque ◽

...

Keyword(s):

Ascorbic Acid ◽

Bioactive Compounds ◽

Antioxidant Properties ◽

Titratable Acidity ◽

Trolox Equivalent Antioxidant Capacity ◽

Trolox Equivalent ◽

Gelatin Coating ◽

Reduced Water ◽

Capacity Method

The Myrtillocactus geometrizans (Mart. ex. Pfeiff.) fruit, locally called garambullo, is an important source of bioactive compounds, mainly betalains, polyphenols, and ascorbic acid. However, information on the application of post-harvest technologies that prolong the shelf life of the fruits is still insufficient. The objective of the present research was to evaluate the effect of a gelatin coating incorporating 0%, 1%, or 3% tomato oily extract (TOE), compared to a control (without coating), on the physicochemical and antioxidant properties of garambullo fruits stored for 15 days at 5 °C. The gelatin coatings with TOE significantly (p ≤ 0.05) delayed changes in weight loss, brix degrees, titratable acidity and pH, compared to the control during storage. Fruits coated with TOE-gelatin had a higher content of betalains, ascorbic acid, total phenols, and flavonoids. The results showed that a higher concentration of phytochemicals increased antioxidant activity in vitro; the maximum values found for Trolox equivalents per kg of fresh weight were 10.46 and 17.65 mM for the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and Trolox Equivalent Antioxidant Capacity Method (TEAC) tests, respectively. The gelatin coating with TOE-3% (COTE-3%) reduced water loss by 1.66 times, compared to the control. In addition, the fruits covered with COTE-3% showed the highest concentration of bioactive compounds during storage.

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Impact of Bovine Lipocalin-2 Gene on the Antioxidant Activity of Milk from Polish Holstein-Friesian Cows

Animals ◽

10.3390/ani9110992 ◽

2019 ◽

Vol 9 (11) ◽

pp. 992 ◽

Cited By ~ 1

Author(s):

Joanna Pokorska ◽

Dominika Kułaj ◽

Agata Piestrzyńska-Kajtoch ◽

Anna Radko

Keyword(s):

Antioxidant Activity ◽

Antioxidant Capacity ◽

Antioxidant Properties ◽

Trolox Equivalent Antioxidant Capacity ◽

Lipocalin 2 ◽

Holstein Friesian ◽

Total Antioxidant ◽

Trolox Equivalent ◽

Daily Milk Yield ◽

Friesian Cows

In the recent years, antioxidant properties of food products have become an important aspect for consumers. Milk is a very good source of easily absorbable proteins and minerals, as well as a valuable source of antioxidants. Lipocalin-2 (LCN2), given that, inter alia, it is produced in large quantities by various types of cells in response to oxidative stress caused by physical or chemical factors, it can be considered a protein that determines the total antioxidant capacity of milk. The main objective of this study was to analyze polymorphisms within the lipocalin-2 gene and to determine their impact on antioxidant activity of milk from Holstein-Friesian cows. The genotyping was carried out by sequencing of PCR products. To determine the antioxidant activity of milk, the Trolox equivalent antioxidant capacity (TEAC) method was used. A total of four polymorphic sites were identified in the examined segment of the bovine lipocalin-2 gene. It was shown that cows of the CC genotype at the locus g.98793763G>C produced milk of significantly higher antioxidant capacity. The antioxidant capacity of milk also varied according to the age of cows, their daily milk yield, and SCC in milk.

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Comparison of Antioxidant Properties of Wild Blueberries (Vaccinium arctostaphylos L. and Vaccinium myrtillus L.) with Cultivated Blueberry Varieties (Vaccinium corymbosum L.) in Artvin Region of Turkey

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v3i1.40-44.166 ◽

2014 ◽

Vol 3 (1) ◽

pp. 40 ◽

Cited By ~ 5

Author(s):

Özlem Saral ◽

Zafer Ölmez ◽

Hüseyin Şahin

Keyword(s):

Wild Species ◽

Antioxidant Activities ◽

Antioxidant Properties ◽

Vaccinium Corymbosum ◽

Vaccinium Myrtillus ◽

Trolox Equivalent Antioxidant Capacity ◽

High Biological Activity ◽

Wild Blueberries ◽

Trolox Equivalent ◽

Vaccinium Myrtillus L

Vaccinium arctostaphylos L. and Vaccinium myrtillus L. which are found naturally in most part of Blacksea Region, and Artvin are generally called bear grape, Trabzon tea, and likapa. In addition, different varieties of blueberry (Vaccinium corymbosum L.) have been cultivated in Artvin region for 5 or 6 years. Blueberries contain appreciable levels of phenolic compounds, including anthocyanins and ﬂavonols that have high biological activity. V. arctostaphylos and V. myrtillus show that natural distrubition with received V. corymbosum of different cultured species in Artvin region will be determined antioxidant activity in this study. In this study showed that wild species had a higher antioxidant effect than cultivated species. V. myrtillus had high total polyphenols (11.539-20.742 mg GAE/g dry sample), flavonoids (1.182-2.676 mg QE/g dry sample) and anthocyanins (3.305-11.473 mg Cyn/g dry sample) than V. corymbosum species. In addition, wild species had high CUPRAC, FRAP and DPPH values. The antioxidant activities found with CUPRAC, expressed as trolox equivalent antioxidant capacity ranged from 0.143 to 0.297 mmol TEAC/g dry sample. Those determined with DPPH expressed as IC50 ranged from 0.229 to 1.178 mg/ml. Those determined with FRAP expressed as FeSO4.7H2O equivalent were in 130.719–346.115 µmol Fe/g dry sample range.

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Polyphenol Composition and Antioxidant Potential of Instant Gruels Enriched with Lycium barbarum L. Fruit

Molecules ◽

10.3390/molecules25194538 ◽

2020 ◽

Vol 25 (19) ◽

pp. 4538

Author(s):

Marta Olech ◽

Kamila Kasprzak ◽

Agnieszka Wójtowicz ◽

Tomasz Oniszczuk ◽

Renata Nowak ◽

...

Keyword(s):

Phenolic Acids ◽

Antioxidant Properties ◽

Trolox Equivalent Antioxidant Capacity ◽

Production Parameter ◽

Polyphenolic Compound ◽

Lycium Barbarum ◽

Functional Additive ◽

Trolox Equivalent ◽

Free Phenolic Acids ◽

Compound Plant

Goji fruit (Lycium barbarum L.) has been identified as a polyphenolic compound plant source of noted richness. It also contains polysaccharides, carotenoids, vitamins and minerals, fatty and organic acids. The purpose of the presented research was to produce innovative instant corn gruels with various dry goji berry contents (1, 3 and 5%), to determine the level of included polyphenolic compounds (including individual free phenolic acids) and to assess the antioxidant properties of these functional-food products. A further objective was to identify the optimum value of one of the most important production parameter, the rotational speed of the extruder’s screw during gruel processing. The undertaken chromatographic analysis (LC-ESI-MS/MS) showed a wide variety of available phenolic acids. In the samples with 5% addition of fruit, eight phenolic acids were detected, whereas in the corn gruel without additives, only five were noted. The antioxidant activity, the content of free phenolic acids and the sum of polyphenols increased with increase of the functional additive. For all goji content, screw speeds of 100 and 120 rpm rather than 80 rpm resulted in higher polyphenol amounts and greater Trolox equivalent antioxidant capacity, as well as higher ability to scavenge DPPH.

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