The Cardiovascular Benefits of Caffeinated Beverages: Real or Surreal? / “Metron Ariston - All in Moderation”

: Caffeinated beverages are the most widely consumed beverages globally with coffee and tea as the two most prominent sources of caffeine. Caffeine content varies across different types of beverages. In addition to caffeine, coffee and tea have other biologically active compounds, and all may affect general and cardiovascular (CV) health. Moderate caffeine consumption (<300-400 mg/day), regardless of the source, is considered safe by both European and US Health Authorities, as it is not associated with adverse health and CV effects, while it may confer certain health benefits. There is a nonlinear association between coffee ingestion and CV risk; moderate coffee drinking is inversely significantly associated with CV risk, with the highest benefit at 2-4 cups per day, while heavy coffee drinking might confer increased risk. With regards to tea, due to a lower caffeine content per serving, its consumption is only limited by the total caffeine daily intake. Both these caffeinated beverages, coffee and tea, have additional phenolic compounds, with anti-oxidant and anti-inflammatory activities, which confer cardioprotective benefits. Of the several coffee compounds, chloroacetic acids and melanoidins offer such beneficial effects, while diterpenes may have unfavorable effects on lipids. Most of the tea ingredients (polyphenols) are cardioprotective. A major concern relates to energy drinks with their much higher caffeine content which puts individuals, especially adolescents and young adults, at high health and CV risk. All these issues are herein discussed, including pertinent studies and meta-analyses, pathogenetic mechanisms involved and relevant recommendations from health authorities.

Microextraction flotamicroextraction flotation concentration and determination of chloroacetic acids in watertion concentration and determination of chloroacetic acids in water

The flotation-assisted liquid-liquid microextraction method of mono-, di -, and trichloroacetic acids (CAAs) has been developed. Methyl tert-butyl ether (MTBE) was used as an extractant. The emulsification was performed by the ultrasonic irradiation. The microextraction procedure was carried out in a 27 ml special tube. It was equipped with the capillaries for sampling the extract and an air outlet. A salting-out additive (Na2SO4) was used to reduce the solubility of MTBE in water and to increase the extraction efficiency of CAAs. The air passage through the emulsion of the extractant was carried out using the eight-channel capillary bubbler. The organic matrix replacement was applied for ion chromatographic determination of CAAs with the conductivity detection. Current study showed the advantages of the flotation-assisted demulsification over the centrifugal one. The concentration factors of chlorinated acetic acids were 2-3 times higher. The detection limits of CAAs in water were reduced to (5·10-4 - 4·10-3 mg/l). The extraction time was reduced by more than three times. The trueness of the determination of HUC impurities was confirmed by the addition method. The statistical insignificance of the systematic error in comparison with the random error was shown. The developed method of preconcentration in combination with ion chromatography made it possible to determine the concentrations of CAAs 40-1250 times lower than the normalized SanPiN and WHO. This allowed conducting a highly sensitive determination of CAAs in water long before the onset of the critical ecological state.

Efficient photolytic degradation of disinfection by-products by using a high photon flux UV system: monochloroacetic acid, dichloroacetic acid and trichloroacetic acid

Photon UV irradiation is promising for organic pollutant decomposition, such as disinfection by-products (DBPs). However, due to the photostability and high water solubility, chloroacetic acids (CAAs) decomposition using routine UV photolysis is very slow. The present study employed a high photon flux UV (3.13 × 104 μmol m−2 s−1) system to investigate its feasibility and suitability for enhancing CAAs (MCAA, DCAA and TCAA) decomposition. The results showed that increasing UV photon flux accelerated the photolysis remarkably. Under the condition of high UV photon flux 3.13 × 104 μmol m−2 s−1, almost complete degradation of 20 mg L−1 MCAA, 20 mg L−1 DCAA, and 20 mg L−1 TCAA in a mixed solution can be achieved within 50, 30 and 25 min, respectively. To the best of our knowledge, efficient photolytic degradation of CAAs in such short time has not been reported. The pseudo-first-order rate constant (kobs) steadily increases with the increasing of UV intensity, indicating that the utilization of light energy is efficient. In addition, the variation of pH from 3.2 to 9.0 showed minor effect on CAAs decomposition in this present studied system. The outcome of this study would be helpful for future employment of high photon flux UV systems for those photolytic resistant pollutants' decomposition.