Sonolysis of natural phenolic compounds in aqueous solutions: degradation pathways and biodegradability

2004 ◽  
Vol 38 (13) ◽  
pp. 3110-3118 ◽  
Author(s):  
Constantinos Vassilakis ◽  
Ariadni Pantidou ◽  
Elefteria Psillakis ◽  
Nicolas Kalogerakis ◽  
Dionissios Mantzavinos
2015 ◽  
Vol 32 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Aleksandar M. Veselinović ◽  
Goran M. Nikolić

SUMMARY Pyrogallol-type phenolic compounds are widespread in nature and may have significant impact on human health. As Zn(II) ion was proved to be capable of enhancing some biological activities of pyrogallol-type natural phenolic compounds, we decided to study its influence on the autoxidation of pyrogallol and gallic acid in weakly acidic aqueous solutions. UV-Vis spectrophotometric measurements showed that autoxidation of pyrogallol was initiated by the influence of Zn(II) ions at pH 5.5 and pH 6.5. The differences in UV-Vis spectra of the first autoxidation products resolved by the application of multivariate curve resolution - alternating least squares (MCR-ALS) method indicated that pH change also changed the mechanism of autoxidation process. Formation of stable Zn(II) ion spin stabilized free radical obtained during the autoxidation of pyrogallol at pH 6.5 was confirmed by using electron spin resonance (ESR) spectroscopy and its structure was determined. Both UV-Vis spectrophotometric and ESR spectroscopic measurements did not give any evidence that gallic acid autoxidation was initiated by the influence of Zn(II) ions in weakly acidic aqueous solutions. The results of this study may be used for explaining possible differences in the Zn(II) ion influence on various biological activities of pyrogallol-type phenolic compounds containing simple pyrogallol moiety and the ones containing gallate moiety as a part of the molecule


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Rakesh E. Mutha ◽  
Anilkumar U. Tatiya ◽  
Sanjay J. Surana

Abstract Background Natural plants and plant-derived formulations have been used by mankind from the ancient period of time. For the past few years, many investigations elaborated the therapeutic potential of various secondary chemicals present in the plants. Literature revealed that the various secondary metabolites, viz. phenolics and flavonoids, are responsible for a variety of therapeutic action in humans. Main body In the present review, an attempt has been made to compile the exploration of natural phenolic compounds with major emphasis on flavonoids and their therapeutic potential too. Interestingly, long-term intake of many dietary foods (rich in phenolics) proved to be protective against the development and management of diabetes, cancer, osteoporosis, cardiovascular diseases and neurodegenerative diseases, etc. Conclusion This review presents an overview of flavonoid compounds to use them as a potential therapeutic alternative in various diseases and disorders. In addition, the present understanding of phenolics and flavonoids will serve as the basis for the next scientific studies.


Meat Science ◽  
2014 ◽  
Vol 97 (2) ◽  
pp. 249-254 ◽  
Author(s):  
Letricia Barbosa-Pereira ◽  
Goizane P. Aurrekoetxea ◽  
Inmaculada Angulo ◽  
Perfecto Paseiro-Losada ◽  
José M. Cruz

2004 ◽  
pp. 199-205 ◽  
Author(s):  
Radomir Malbasa ◽  
Eva Loncar ◽  
Ljiljana Kolarov

Black and green tea contains a wide range of natural phenolic compounds Flavanoids and their glycosides, catechins and the products of their condensation, and phenolic acids are the most important. Kombucha beverage is obtained by fermentation of tea fungus on black or green tea sweetened with sucrose. The aim of this paper was to investigate the composition of some phenolic compounds, catechin, epicatechin, quercetin, myricetin, gallic and tanic acid, and monitoring of their status during tea fungus fermentation. The method used for this study was thin layer chromatography with two different systems. The main phenolic compounds in the samples with green tea were catechin and epicatechin, and in the samples with black tea it was quercetin.


2021 ◽  
Author(s):  
Julie Becher ◽  
Samuel Beal ◽  
Susan Taylor ◽  
Katerina Dontsova ◽  
Dean Wilcox

Two major components of insensitive munition formulations, nitroguanidine (NQ) and 3-nitro-1,2,4-triazol-5-one (NTO), are highly water soluble and therefore likely to photo-transform while in solution in the environment. The ecotoxicities of NQ and NTO solutions are known to increase with UV exposure, but a detailed accounting of aqueous degradation rates, products, and pathways under different exposure wavelengths is currently lacking. We irradiated aqueous solutions of NQ and NTO over a 32-h period at three ultraviolet wavelengths and analyzed their degradation rates and transformation products. NQ was completely degraded by 30 min at 254 nm and by 4 h at 300 nm, but it was only 10% degraded after 32 h at 350 nm. Mass recoveries of NQ and its transformation products were >80% for all three wavelengths. NTO degradation was greatest at 300 nm with 3% remaining after 32 h, followed by 254 nm (7% remaining) and 350 nm (20% remaining). Mass recoveries of NTO and its transformation products were high for the first 8 h but decreased to 22–48% by 32 h. Environmental half-lives of NQ and NTO in pure water were estimated as 4 and 6 days, respectively. We propose photo-degradation pathways for NQ and NTO supported by observed and quantified degradation products and changes in solution pH.


Langmuir ◽  
2001 ◽  
Vol 17 (11) ◽  
pp. 3301-3306 ◽  
Author(s):  
Fritz Stoeckli ◽  
M. Victoria López-Ramón ◽  
Carlos Moreno-Castilla

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