Article

1998 ◽  
Vol 76 (2) ◽  
pp. 171-182 ◽  
Author(s):  
Fengde Xi ◽  
L Ross Barclay
Keyword(s):  
Methyl Linoleate ◽  
Antioxidant Activities ◽  
Lignin Content ◽  
Synergistic Effects ◽  
Sodium Dodecyl ◽  
Ascorbyl Palmitate ◽  
Semiquinone Radical ◽  
Semiquinone Radicals ◽  
Sds Micelles

The antioxidant activities, kinh, of catechol, 1, 4-tert-butylcatechol, 2, and 3,5-di-tert-butylcatechol (DTBC), 3, determined by the inhibited oxygen-uptake method during peroxidation of styrene initiated by AIBN are 55.0 x 104, 88.4 x 104, and 149 x 104 M-1s-1, respectively, and the stoichiometric factors (n) were 2.1-2.3. A decrease by 50-fold in kinh for 3 and a drop of 1.1-1.4 in n observed during inhibited peroxidation of methyl linoleate in aqueous sodium dodecyl sulfate (SDS) initiated by di-tert-butylhyponitrile (DBHN) is attributed to hydrogen bonding by water on the antioxidant and on the intermediate di-tert-butylsemiquinone radical, 5, formed in the inhibition step. Combinations of ascorbyl palmitate with 3 exhibited cooperative (not synergistic) antioxidant effects during inhibited peroxidation of styrene in solution. Combinations of ascorbic acid with 3 exhibited synergistic effects during inhibited peroxidation of methyl linoleate initiated by DBHN in SDS micelles. A profile of the effect of concentration of ascorbate on this synergism indicates a mole of 3 is regenerated per mole of ascorbate. The thiols, homocysteine, and polyethylene glycol thiol (polythiol) also exhibited synergistic effects with DTBC in this inhibition. Either ascorbate or polythiol rapidly reduces di-tert-butyl-ortho-quinone (DTBQ), 4, to 3 in methanol or in SDS micelles, and the combination of 3 + ascorbate acted as an efficient inhibitor in this medium. The esr studies indicate the semiquinone radical, 5, produced photochemically from 3 or spontaneously from 3 + 4 in solution, to be very persistent at room temperature. A pathway, mediated by 5, is proposed to account for the cooperative and synergistic effects observed and for the additional combination effect discovered when the three inhibitors: 3, ascorbate, and a thiol are used in the SDS medium. Combinations of such antioxidants are expected to be useful for inhibition of yellowing of pulps and paper with high lignin content, and to be significant in the in vivo reductions of ortho-quinones and semiquinone radicals formed during oxidations of various biomolecules.Key words: catechols, ascorbate, thiols, radicals, antioxidants.

scholarly journals Nutraceutical Activity in Osteoarthritis Biology: A Focus on the Nutrigenomic Role

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1232
Author(s):  
Stefania D’Adamo ◽  
Silvia Cetrullo ◽  
Veronica Panichi ◽  
Erminia Mariani ◽  
Flavio Flamigni ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Antioxidant Activities ◽  
Synergistic Effects ◽  
National Health System ◽  
Bioactive Molecules ◽  
Joint Disease ◽  
In Vivo Studies ◽  
Wide Range

Osteoarthritis (OA) is a disease associated to age or conditions that precipitate aging of articular cartilage, a post-mitotic tissue that remains functional until the failure of major homeostatic mechanisms. OA severely impacts the national health system costs and patients’ quality of life because of pain and disability. It is a whole-joint disease sustained by inflammatory and oxidative signaling pathways and marked epigenetic changes responsible for catabolism of the cartilage extracellular matrix. OA usually progresses until its severity requires joint arthroplasty. To delay this progression and to improve symptoms, a wide range of naturally derived compounds have been proposed and are summarized in this review. Preclinical in vitro and in vivo studies have provided proof of principle that many of these nutraceuticals are able to exert pleiotropic and synergistic effects and effectively counteract OA pathogenesis by exerting both anti-inflammatory and antioxidant activities and by tuning major OA-related signaling pathways. The latter are the basis for the nutrigenomic role played by some of these compounds, given the marked changes in the transcriptome, miRNome, and methylome. Ongoing and future clinical trials will hopefully confirm the disease-modifying ability of these bioactive molecules in OA patients.

scholarly journals Enhancement of the Antibacterial Activity of Silver Nanoparticles against Phytopathogenic BacteriumRalstonia solanacearumby Stabilization

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Juanni Chen ◽  
Shili Li ◽  
Jinxiang Luo ◽  
Rongsheng Wang ◽  
Wei Ding
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Synergistic Effects ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Tween 80 ◽  
Phytopathogenic Bacterium ◽  
Crop Disease

In this paper, the enhanced antibacterial activity of silver nanoparticles (AgNPs) against the phytopathogenic bacteriumRalstonia solanacearumafter stabilization using selected surfactants (SDS, SDBS, TX-100, and Tween 80) was examined, in comparison with silver ion. Tween 80 was found to be the most preferable stabilizer of AgNPs due to the beneficial synergistic effects of the AgNPs and surfactant. However, all the surfactants nearly had no effects on the antibacterial activity of Ag+.In vitro, Tween 80-stabilized AgNPs showed the highest bactericidal activity againstR. solanacearum. Further measurements using TEM, fluorescence microscopy, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that though Ag+and Tween 80-Ag+induced high toxicity, Tween 80-stabilized AgNPs displayed most severe damage when in direct contact with cells, causing mechanistic injury to the cell membrane and strongly modifying and destructing the cellular proteins. Meanwhile,in vivo, the pot experiments data indicated that the control efficiency of Tween 80-stabilized AgNPs on tobacco bacterial wilt was 96.71%, 90.11%, and 84.21%, at 7 days, 14 days, and 21 days, respectively. Based on the results evidencing their advantageous low dosage requirements and strong antimicrobial activity, Tween 80-stabilized AgNPs are a promising antibacterial agent for use in alternative crop disease control approaches.

The autoxidation of unsaturated lipids in micelles. Synergism of inhibitors vitamins C and E

1983 ◽  
Vol 61 (6) ◽  
pp. 1288-1290 ◽  
Author(s):  
Lawrence Ross Coates Barclay ◽  
Steven Jeffrey Locke ◽  
Joseph Mark MacNeil
Keyword(s):  
Linoleic Acid ◽  
Methyl Linoleate ◽  
Sodium Dodecyl ◽  
Square Root ◽  
Micellar Phase ◽  
Chain Initiation ◽  
Unsaturated Lipids ◽  
Sds Micelles ◽  
Initiator Efficiency ◽  
Kinetics Of

The kinetics of thermally (30 °C) initiated autoxidations of unsaturated lipids, linoleic acid, and methyl linoleate are studied in 0.50 M sodium dodecyl sulfate (SDS) micelles. The rate of chain initiation, R1, was controlled by using known amounts of the thermal initiator, di-tert-butylhyponitrite (DBHN). The initiator efficiency, e, determined by the induction period method with x-tocopherol, was 0.30 for linoleic acid and varied (0.30 to 0.36) for methyl linoleate autoxiation as the concentration of the ester increased. The rate of autoxidation of linoleic acid follows the classical rate law since it is proportional to the substrate concentration and to the square root of chain initiation. The oxidizability of linoleic acid measured in micelles is 4.09 × 10−2 M−1/2 s−1/2. The oxidizability of methyl linoleate varied from 2.37 × 10−2 to 6.92 × 10−2 M−1/2 s−1/2 as the amount of solubilized ester increased. The latter results are indicative of pooling of the ester in the micellar phase. Additions of aqueous solutions of ascorbic acid to α-tocopherol-inhibited micellar autoxidations result in very significant extensions of the efficient inhibition period compared to that obtained with α-tocopherol alone. The mechanism of this synergism is briefly discussed.

Cardioprotective Effects of Diet with Different Grains on Lipid Profiles and Antioxidative System in Obesity-Induced Rats

2012 ◽  
Vol 82 (2) ◽  
pp. 85-93 ◽  
Author(s):  
Y. Kim ◽  
H. Shin ◽  
S. Lee
Keyword(s):  
Aortic Wall ◽  
Plasma Lipids ◽  
Antioxidant Activities ◽  
Plasma Lipid ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Lipid Profiles ◽  
Dietary Lipids ◽  
Male Rats

In the present study, the nutritional quality of four grains including adlay (AD), buckwheat (BW), glutinous barley (GB), and white rice (WR) were evaluated in terms of plasma lipid parameters, gut transit time, and thickness of the aortic wall in rats. The rats were then raised for 4 weeks on the high-fat diet based on the American Institute of Nutrition-93 (AIN-93 G) diets containing 1 % cholesterol and 20 % dietary lipids. Forty male rats were divided into 4 groups and raised for 4 weeks with a diet containing one of the following grains: WR, AD, BW, or WB. The level of thiobarbituric acid-reactive substances (TBARS) in liver was shown to be higher in rats by the order of those fed WR, AD, GB, and BW. This indicates that other grains decreased oxidative stress in vivo more than WR. The superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase levels in the AD, BW, and GB groups were significantly higher than those in the WR group (p < 0.05). Plasma lipid profiles differed significantly according to grain combination, and decreased aortic wall thickness was consistent with the finding of decreased plasma low-density lipoprotein cholesterol (LDL-C) (p < 0.05) and increased high-density lipoprotein (HDL-C) in rats fed AD, BW, and GB (p < 0.001). The antioxidant and hypolipidemic capacities of grains are quite high, especially those of adlay, buckwheat, and glutinous barley. In conclusion, this study has demonstrated that the whole grains had a cardioprotective effect. This effect was related to several mechanisms that corresponded to lowering plasma lipids, decreasing TBARS, and increasing antioxidant activities.

In vitro and in vivo antioxidant activities of the leaves of Chrysophyllum albidum

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
AH Adebayo ◽  
AO Abolaji ◽  
OO Ayepola ◽  
TB Olorunfemi ◽  
OS Taiwo
Keyword(s):  
Antioxidant Activities

Synergistic Effects of Implant Macrogeometry and Surface Physicochemical Modifications on Osseointegration: An In Vivo Experimental Study in Sheep

2019 ◽  
Vol 29 (4) ◽  
pp. 295-302 ◽  
Author(s):  
Edmara T. P. Bergamo ◽  
Paula G. F. P de Oliveira ◽  
Ryo Jimbo ◽  
Rodrigo Neiva ◽  
Nick Tovar ◽  
...  
Keyword(s):  
Experimental Study ◽  
Synergistic Effects

Punica granatum as a Source of Natural Antioxidant and Antimicrobial Agent; a Comprehensive Review on Related Investigations

2020 ◽  
Vol 17 ◽  
Author(s):  
Atefeh Jalali ◽  
Mohammadreza Kiafar ◽  
Masih Seddigh ◽  
Mohammad M. Zarshenas
Keyword(s):  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Natural Antioxidants ◽  
Punica Granatum ◽  
Antimicrobial Activities ◽  
Natural Antioxidant ◽  
Antiviral Activities ◽  
Natural Foods

Background: The consumption of natural antioxidants is increasing due to the demand and tendency to natural foods. Punica granatum L. [Punicaceae] is a fruit with various bioactive ingredients. The effectiveness of this plant has been proved against various disorders such as hyperglycemia, hyperlipidemia, blood coagulation, infections, cancer, and dentistry. Among them, there are numerous researches on antimicrobial and antioxidant properties. Subsequently, the present study aimed to compile a review of those properties to outline this herb as a possible natural antioxidant and preservative. Methods: Synchronically, keywords "Punica granatum" with antimicrobial, or antibacterial, antifungal, antiviral, antioxidant and radical scavenging were searched through "Scopus" database up to 31st September 2019. Papers focusing on agriculture, genetics, chemistry, and environmental sciences were excluded and also related papers were collected. Results: Among 201 papers focusing on related activities, 111 papers have dealt with antioxidant activities focusing based on DPPH assay, 59 with antibacterial, on both gram+ and gram- bacteria, 24 with antifungal effects, mostly on Aspergillus niger and Candida albicans, and 7 papers with antiviral activities. There were about 50 papers focusing on in-vivo antioxidant activities of this plant. Conclusion: Taken together, botanical parts of P. granatum have possessed notable radical scavenging and antimicrobial activities that with these properties, this plant can be introduced as a natural safe source of preservative and antioxidant. Accordingly, P. granatum can be applied as excipient with the aforementioned properties in the pharmaceutical and food industries.

Recent Patents on Anti-Cancer Potential of Helenalin

2020 ◽  
Vol 15 (2) ◽  
pp. 132-142
Author(s):  
Priyanka Kriplani ◽  
Kumar Guarve
Keyword(s):  
Synergistic Effects ◽  
Therapeutic Interventions ◽  
Active Constituent ◽  
Scientific Impact ◽  
Isolation Techniques ◽  
Anti Cancer ◽  
Prevention Of Cancer ◽  
Synthetic Derivatives

Background: Arnica montana, containing helenalin as its principal active constituent, is the most widely used plant to treat various ailments. Recent studies indicate that Arnica and helenalin provide significant health benefits, including anti-inflammatory, neuroprotective, antioxidant, cholesterol-lowering, immunomodulatory, and most important, anti-cancer properties. Objective: The objective of the present study is to overview the recent patents of Arnica and its principal constituent helenalin, including new methods of isolation, and their use in the prevention of cancer and other ailments. Methods: Current prose and patents emphasizing the anti-cancer potential of helenalin and Arnica, incorporated as anti-inflammary agents in anti-cancer preparations, have been identified and reviewed with particular emphasis on their scientific impact and novelty. Results: Helenalin has shown its anti-cancer potential to treat multiple types of tumors, both in vitro and in vivo. It has also portrayed synergistic effects when given in combination with other anti- cancer drugs or natural compounds. New purification/isolation techniques are also developing with novel helenalin formulations and its synthetic derivatives have been developed to increase its solubility and bioavailability. Conclusion: The promising anti-cancer potential of helenalin in various preclinical studies may open new avenues for therapeutic interventions in different tumors. Thus clinical trials validating its tumor suppressing and chemopreventive activities, particularly in conjunction with standard therapies, are immediately required.

scholarly journals Investigating the Feasibility of Mefenamic Acid Nanosuspension for Pediatric Delivery: Preparation, Characterization, and Role of Excipients

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 574
Author(s):  
Nikhat Perween ◽  
Sultan Alshehri ◽  
T. S. Easwari ◽  
Vivek Verma ◽  
Md. Faiyazuddin ◽  
...  
Keyword(s):  
Particle Size ◽  
Mefenamic Acid ◽  
Hydroxypropyl Methylcellulose ◽  
Sodium Dodecyl ◽  
Aqueous Solubility ◽  
Oral Route ◽  
Precipitation Method ◽  
Antisolvent Precipitation

Molecules with poor aqueous solubility are difficult to formulate using conventional approaches and are associated with many formulation delivery issues. To overcome these obstacles, nanosuspension technology can be one of the promising approaches. Hence, in this study, the feasibility of mefenamic acid (MA) oral nanosuspension was investigated for pediatric delivery by studying the role of excipients and optimizing the techniques. Nanosuspensions of MA were prepared by adopting an antisolvent precipitation method, followed by ultrasonication with varying concentrations of polymers, surfactants, and microfluidics. The prepared nanosuspensions were evaluated for particle size, morphology, and rheological measures. Hydroxypropyl methylcellulose (HPMC) with varying concentrations and different stabilizers including Tween® 80 and sodium dodecyl sulfate (SLS) were used to restrain the particle size growth of the developed nanosuspension. The optimized nanosuspension formula was stable for more than 3 weeks and showed a reduced particle size of 510 nm with a polydispersity index of 0.329. It was observed that the type and ratio of polymer stabilizers were responsive on the particle contour and dimension and stability. We have developed a biologically compatible oral nanoformulation for a first-in-class drug beautifully designed for pediatric delivery that will be progressed toward further in vivo enabling studies. Finally, the nanosuspension could be considered a promising carrier for pediatric delivery of MA through the oral route with enhanced biological impact.

scholarly journals Effective decellularisation of human saphenous veins for biocompatible arterial tissue engineering applications: Bench optimisation and feasibility in vivo testing

2021 ◽  
Vol 12 ◽  
pp. 204173142098752
Author(s):  
Nadiah S Sulaiman ◽  
Andrew R Bond ◽  
Vito D Bruno ◽  
John Joseph ◽  
Jason L Johnson ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Mechanical Strength ◽  
Vascular Tissue ◽  
Sodium Dodecyl ◽  
Host Cells ◽  
Replacement Model ◽  
In Vivo Testing ◽  
Vascular Scaffolds

Human saphenous vein (hSV) and synthetic grafts are commonly used conduits in vascular grafting, despite high failure rates. Decellularising hSVs (D-hSVs) to produce vascular scaffolds might be an effective alternative. We assessed the effectiveness of a detergent-based method using 0% to 1% sodium dodecyl sulphate (SDS) to decellularise hSV. Decellularisation effectiveness was measured in vitro by nuclear counting, DNA content, residual cell viability, extracellular matrix integrity and mechanical strength. Cytotoxicity was assessed on human and porcine cells. The most effective SDS concentration was used to prepare D-hSV grafts that underwent preliminary in vivo testing using a porcine carotid artery replacement model. Effective decellularisation was achieved with 0.01% SDS, and D-hSVs were biocompatible after seeding. In vivo xeno-transplantation confirmed excellent mechanical strength and biocompatibility with recruitment of host cells without mechanical failure, and a 50% patency rate at 4-weeks. We have developed a simple biocompatible methodology to effectively decellularise hSVs. This could enhance vascular tissue engineering toward future clinical applications.

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