scholarly journals Glycosylation of resveratrol protects it from enzymic oxidation

2003 ◽  
Vol 374 (1) ◽  
pp. 157-163 ◽  
Author(s):  
Gilly REGEV-SHOSHANI ◽  
Oded SHOSEYOV ◽  
Itzhak BILKIS ◽  
Zohar KEREM
Keyword(s):  
Hydroxy Group ◽  
Biological Properties ◽  
Plant Polyphenols ◽  
Lower Affinity ◽  
Polyphenol Oxidases ◽  
Dietary Polyphenols ◽  
Enzymic Oxidation ◽  
Beneficial Effects ◽  
One Step ◽  
Kinetics Of

Plant polyphenols, including dietary polyphenols such as resveratrol, are important components in the plant antioxidant and defence systems. They are also known to exert beneficial effects on human health through diet. As they are produced, these polyphenols may be subjected to deleterious enzymic oxidation by the plant polyphenol oxidases. They are generally synthesized as glycosides like 5,4′-dihydroxystilbene-3-O-β-d-glucopyranoside, the 3-glucoside of resveratrol. The effects of the glycosylation and methylation of the parent resveratrol on its enzymic oxidation were studied. Methyl and glucosyl derivatives were synthesized using simple one-step methodologies. The kinetics of their enzymic oxidation by tyrosinases were defined. Substitution at the p-hydroxy group, by either glucose or methyl, abolished enzymic oxidation by both mushroom and grape tyrosinases. Substitution at the m-hydroxy group with methyl had a small effect, but substitution with glucose resulted in a much lower affinity of the enzymes for the glycoside. We suggest that glycosylation of polyphenols in nature helps to protect these vital molecules from enzymic oxidation, extending their half-life in the cell and maintaining their beneficial antioxidant capacity and biological properties.

Potential Anti-inflammatory Effects of Hesperidin from the Genus Citrus

2019 ◽  
Vol 25 (37) ◽  
pp. 4929-4945 ◽  
Author(s):  
Silvia Tejada ◽  
Samuel Pinya ◽  
Miquel Martorell ◽  
Xavier Capó ◽  
Josep A. Tur ◽  
...  
Keyword(s):  
Large Family ◽  
Potential Effect ◽  
Biological Properties ◽  
High Concentration ◽  
Specific Mechanism ◽  
Bioactive Substances ◽  
Dietary Polyphenols ◽  
Beneficial Effects ◽  
Anti Inflammatory ◽  
Antioxidant Effects

Background: The benefits of the Mediterranean diet for protecting against many diseases are usually attributed to high consumption of certain foods, characterized by the presence of bioactive substances such as polyphenols. Inflammation plays an important role in the pathogenesis of numerous diseases such as arthritis, allergies or neurodegenerative disorders. Dietary polyphenols constitute a large family of bioactive substances with potential beneficial effects against a broad group of diseases. Citrus fruits and juices are a rich source of vitamin C and flavonoids, with a potential effect on the inflammatory response. Objective: The aim was to evidence the potential anti-inflammatory effects of the flavonoids hesperidin for its possible therapeutic application against diverse pathologies. Method: In the present review, available literature about the anti-inflammatory effects of hesperidin is reported and discussed. Moreover, we also discuss the chemistry, bioavailability and proposed mechanisms of action of hesperidin. Results: Hesperidin is a flavonoid present in high concentration in citrus species and has numerous biological properties, principally antioxidant and anti-inflammatory. Several studies have been performed in order to evaluate the effects of hesperidin as anti-inflammatory agent using cellular and animal models and few clinical trials. Hesperidin treatment decreased inflammatory mediators and exerted significant antioxidant effects. The molecular basis for its anti-inflammatory effects seems to be mediated by signalling pathways especially the nuclear factor κβ pathway. Conclusion: Although hesperidin evidenced anti-inflammatory effects, the specific mechanism of action is not completely known and additional studies are required for elucidation of the molecular targets.

Diosgenin: Therapeutic Action, Pharmacology and Applications

2017 ◽  
Vol 5 (1) ◽  
pp. 7-15
Author(s):  
Sanasam Sanjeev ◽  
◽  
Maibam Sunita Devi ◽  
Khushboo Maurya ◽  
Vikas Kumar Roy ◽  
...  
Keyword(s):  
Hepatitis C ◽  
Drug Development ◽  
Liver Diseases ◽  
Potential Role ◽  
Wide Spectrum ◽  
Herbal Product ◽  
Biological Properties ◽  
Therapeutic Action ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Beneficial Effects

Diosgenin [25R-spriost-5-en-3þ-ol], is an important steroidal metabolite found in various plant species. The discovery of diosgenin has made it one of the most researched and studied herbal product. Moreover, there is excellent opportunity to address whether diosgenin plays a role in chemoprevention versus therapy, or both. However, rigorous experimental based evidence in support of ethnomedicine-derived notions would lead to the development of products relevant to drug development. The health beneficial effects of diosgenin are further extended to its potential role to treat other ailments such as HIV and hepatitis-C infections as well as liver diseases. There is little information regarding the bioavailability, pharmacokinetics and pharmacodynamics of diosgenin in relation to its health beneficial effects. It has been reported to have wide spectrum of biological properties that contributes to several diseases in its role as a health beneficial phytochemical by citing new studies.

scholarly journals Evaluation of Leaf Litter Mulching and Incorporation on Skid Trails for the Recovery of Soil Physico-Chemical and Biological Properties of Mixed Broadleaved Forests

Land ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 625
Author(s):  
Meghdad Jourgholami ◽  
Azadeh Khoramizadeh ◽  
Angela Lo Monaco ◽  
Rachele Venanzi ◽  
Francesco Latterini ◽  
...  
Keyword(s):  
Soil Properties ◽  
Soil Compaction ◽  
Biological Properties ◽  
Soil Protection ◽  
Natural Soil ◽  
Compacted Soils ◽  
Beneficial Effects ◽  
Physico Chemical ◽  
Forest Logging ◽  
Soil Recovery

Engineering applications can be used to mitigate the adverse effects of soil compaction and amend compacted soils. Previous literature has highlighted the beneficial effects of interventions such as litter mulching and incorporation on skid trails. However, little is known about the effectiveness of these alternatives in restoring forest soil quality after forest logging. The objective of this study was to properly elucidate the effects of the above mentioned soil protection methods, litter incorporation before skidding (LI) and litter mulching after skidding (LM), on the recovery of compacted soil’s physico-chemical and biological properties on skid trails over a 2-year period in the Hyrcanian forests of Iran to identify the best option for restoration intervention. The litter used in both methods consisted of dried leaves of the hornbeam and maple tree in three intensities of 3, 6, and 9 Mg ha−1. The results showed that the application of both methods (LI and LM) significantly improved the soil properties when compared to the untreated skid trail. Results showed that the recovery values of soil properties in the LI treatments were significantly higher than those of the LM. The recovery values of soil properties by 6 and 9 Mg ha−1 were significantly higher than those of 3 Mg ha−1, while the differences were not significant between 6 and 9 Mg ha−1. Our findings showed that soil properties were partially recovered (70–80%) over a 2-year period from treatment, compared to untreated, but the full recovery of soil properties required more time to return to the pre-harvest value. Overall, the results of this study demonstrated that the application of soil protection methods accelerates the process of recovering soil properties much faster than natural soil recovery, which can take more than 20 years in these forests.

scholarly journals Anti-Obesity Effects of Polyphenol Intake: Current Status and Future Possibilities

2020 ◽  
Vol 21 (16) ◽  
pp. 5642 ◽  
Author(s):  
Mariarosaria Boccellino ◽  
Stefania D’Angelo
Keyword(s):  
Lifestyle Modification ◽  
Food Supplement ◽  
Biological Properties ◽  
Current Status ◽  
Dietary Polyphenols ◽  
Balanced Diet ◽  
Increase Energy Expenditure ◽  
Prevalence Of Obesity ◽  
Polyphenol Intake ◽  
Study Designs

The prevalence of obesity has steadily increased worldwide over the past three decades. The conventional approaches to prevent or treat this syndrome and its associated complications include a balanced diet, an increase energy expenditure, and lifestyle modification. Multiple pharmacological and non-pharmacological interventions have been developed with the aim of improving obesity complications. Recently, the use of functional foods and their bioactive components is considered a new approach in the prevention and management of this disease. Due to their biological properties, polyphenols may be considered as nutraceuticals and food supplement recommended for different syndromes. Polyphenols are a class of naturally-occurring phytochemicals, some of which have been shown to modulate physiological and molecular pathways involved in energy metabolism. Polyphenols could act in the stimulation of β-oxidation, adipocyte differentiation inhibition, counteract oxidative stress, etc. In this narrative review, we considered the association between polyphenols (resveratrol, quercetin, curcumin, and some polyphenolic extracts) and obesity, focusing on human trials. The health effects of polyphenols depend on the amount consumed and their bioavailability. Some results are contrasting, probably due to the various study designs and lengths, variation among subjects (age, gender, ethnicity), and chemical forms of the dietary polyphenols used. But, in conclusion, the data so far obtained encourage the setting of new trials, necessary to validate benefic role of polyphenols in obese individuals.

Role of the C(6)-Hydroxy Group in Bicyclomycin:  Synthesis, Structure, and Chemical, Biochemical, and Biological Properties

1998 ◽  
Vol 41 (7) ◽  
pp. 1185-1194 ◽  
Author(s):  
Alejandro Santillán, ◽  
Xiangdong Zhang ◽  
Jon Hardesty ◽  
William R. Widger ◽  
Kohn
Keyword(s):  
Hydroxy Group ◽  
Biological Properties

Beneficial effects of dietary polyphenols in the prevention and treatment of NAFLD: cell-signaling pathways underlying health effects

2021 ◽  
Vol 28 ◽  
Author(s):  
Francisca Echeverría ◽  
Andrés Bustamante ◽  
Verónica Sambra ◽  
Daniela Álvarez ◽  
Luis Videla ◽  
...  
Keyword(s):  
Liver Disease ◽  
Health Effects ◽  
De Novo Lipogenesis ◽  
Liver Fat ◽  
Alcoholic Fatty Liver ◽  
Dietary Polyphenols ◽  
Beneficial Effects ◽  
Inflammatory Status ◽  
Pubmed Database ◽  
Prevention And Treatment

Background: Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic accretion of triacylglycerides in the absence of alcohol intake that may progress to steatohepatitis, fibrosis and cirrhosis, becoming the main cause of chronic liver disease. This article discusses recent data concerning the use of dietary polyphenols in the prevention and treatment of NAFLD in vitro, in vivo, and in clinical trials. Methods: Study searches were performed using the PubMed database from the National Library of Medicine-National Institutes of Health. Results: Polyphenols exert beneficial effects in NAFLD, with positive outcomes being related to body weight gain, insulin resistance, liver fat accumulation, oxidative stress, pro-inflammatory status, mitochondrial dysfunction and ER stress. Data reported for hydroxytyrosol suggest that the activation of the hepatic PPAR-α-FGF21-AMPK-PGC-1α signaling cascade is associated with fatty acid oxidation enhancement, de novo lipogenesis diminution and recovery of mitochondrial function, a contention that is supported by the actions of several polyphenols on specific components of this signaling pathway. Besides, polyphenols downregulate NF-κB, suppressing the pro-inflammatory state developed in NAFLD and upregulate liver Nrf2, increasing the cellular antioxidant potential. The latter feature of polyphenols is contributed by chelation of pro-oxidant trace elements, reduction of free radicals to stable forms and inhibition of free radical generating systems. Conclusion: Polyphenols are relevant bioactive compounds in terms of prevention and treatment of NAFLD, which exhibit low bioavailability and instability in biological systems that could limit their health effects. These drawbacks reinforce the necessity of further studies to improve the efficacy of polyphenol formulations for human interventions.

scholarly journals Determination of Dental Adhesive Composition throughout Solvent Drying and Polymerization Using ATR–FTIR Spectroscopy

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3886
Author(s):  
Arwa Almusa ◽  
António H.S. Delgado ◽  
Paul Ashley ◽  
Anne M. Young
Keyword(s):  
Light Exposure ◽  
Light Emitting Diode ◽  
Attenuated Total Reflectance ◽  
Drying Time ◽  
Light Emitting ◽  
Spectral Changes ◽  
One Step ◽  
Urethane Dimethacrylate ◽  
Kinetics Of

The of this study aim was to develop a rapid method to determine the chemical composition, solvent evaporation rates, and polymerization kinetics of dental adhesives. Single-component, acetone-containing adhesives One-Step (OS; Bisco, USA), Optibond Universal (OU; Kerr, USA), and G-Bond (GB; GC, Japan) were studied. Filler levels were determined gravimetrically. Monomers and solvents were quantified by comparing their pure Attenuated Total Reflectance-Fourier Transform Infra-Red (ATR–FTIR) spectra, summed in different ratios, with those of the adhesives. Spectral changes at 37 °C, throughout passive evaporation for 5 min, then polymerisation initiated by 20 s, and blue light emitting diode (LED) (600 mW/cm2) exposure (n = 3) were determined. Evaporation and polymerisation extent versus time and final changes were calculated using acetone (1360 cm−1) and methacrylate (1320 cm−1) peaks. OS, OU, and GB filler contents were 0, 9.6, and 5.3%. FTIR suggested OS and OU were Bis-GMA based, GB was urethane dimethacrylate (UDMA) based, and that each had a different diluent and acidic monomers and possible UDMA/acetone interactions. Furthermore, initial acetone percentages were all 40−50%. After 5 min drying, they were 0% for OS and OU but 10% for GB. Whilst OS had no water, that in OU declined from 18 to 10% and in GB from 25 to 20% upon drying. Evaporation extents were 50% of final levels at 23, 25, and 113 s for OS, OU, and GB, respectively. Polymerisation extents were all 50 and 80% of final levels before 10 and at 20 s of light exposure, respectively. Final monomer polymerisation levels were 68, 69, and 88% for OS, OU, and GB, respectively. An appreciation of initial and final adhesive chemistry is important for understanding the properties. The rates of evaporation and polymerisation provide indications of relative required drying and light cure times. UDMA/acetone interactions might explain the considerably greater drying time of GB.

One‐step synthesis of amino‐functionalised magnetic mesoporous silica and synergistic adsorption kinetics of tetracycline and copper

2018 ◽  
Vol 13 (8) ◽  
pp. 1219-1223 ◽  
Author(s):  
Mancheng Zhang ◽  
Wei Wang ◽  
Zengyin Zhu ◽  
Changsheng Qu ◽  
Qing Zhou ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Adsorption Kinetics ◽  
One Step ◽  
Kinetics Of ◽  
Magnetic Mesoporous Silica

scholarly journals A novel nano zero-valent iron@chitosan for effective removal of Microcystin-LR: Kinetics and adsorption mechanism

2018 ◽  
Vol 53 ◽  
pp. 04004 ◽  
Author(s):  
Xiaofan Yang ◽  
Xueyu Wei ◽  
Xiaoping Xu ◽  
Zhigang Liu
Keyword(s):  
Low Cost ◽  
Spherical Shape ◽  
Step Method ◽  
Variable Parameters ◽  
Transmission Electron ◽  
Effective Removal ◽  
Initial Ph ◽  
Nano Zero Valent Iron ◽  
One Step ◽  
Kinetics Of

Microcystin-LR (MC-LR) is one of the most notorious toxins liberated from cyanobacteria in drinking water sources. In this study, a skillful method access to new nanozero-valent iron @chitosan (nZVIMC) was synthesized by a facile one step method. The as-prepared nZVIMC was employed as an adsorbent for the effective removal MC-LR from aqueous solution. Transmission electron microscopy (TEM) demonstrates that nZVIMC is in quasi-spherical shape with size of around 50 nm, effect of variable parameters such as pH, contact time, initial concentration of MC-LR and adsorption properties of nZVIMC on MC-LR was further investigated. Scanning electron microscope (SEM) reveals that the particles are nearly spherical in shape with agglomeration. The results indicated that good adsorption performance was achieved at an initial pH of 5. The adsorption kinetics of nZVIMC was better fitted by pseudo-secondorder kinetics. The adsorption isotherm data was fitted well to Langmuir isotherm and then to Freundlich model, with an adsorption capacity of 68.9 mg/g at 300K. Thus, we believe that nZVIMC can be used as a low cost material for efficient removal of MC-LR from water.

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