Note. Caffeine Content and Dynamical Bitterness of Yerba Mate Ilex paraguariensis Infusions

2005 ◽  
Vol 11 (6) ◽  
pp. 401-407 ◽  
Author(s):  
A. M. Calviño ◽  
O. P. Tamasi ◽  
M. C. Ciappini
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Time Course ◽  
Total Duration ◽  
Area Under The Curve ◽  
Maximum Intensity ◽  
Ilex Paraguariensis ◽  
Yerba Mate ◽  
Caffeine Content

The infusion of yerba mate (YM) Ilex paraguariensis, with its typical bitterness, is traditionally consumed in South America as a mild stimulant beverage. Two types of YM, with sticks (YM-S) and without sticks (YM-L) and three brands for each type were evaluated for caffeine content and the time course of bitterness. The chemical analysis of the six YM infusions at 5% w/v made by high performance liquid chromatography (HPLC) showed that caffeine levels were higher for YM-L brands. The kinetic study of YM bitterness assessed by time-intensity (TI) curves revealed that the presence of sticks lowered maximum intensity, total duration and area under the curve of bitter perception.

scholarly journals Performance of Caffeine Content Analysis in Robusta sp and Theobroma cacao L using Iodometry, UV-Vis Spectrophotometry and High Performance Liquid Chromatography

2020 ◽  
Vol 9 (3) ◽  
pp. 212-221
Author(s):  
Yeanchon H. Dulanlebit ◽  
◽  
Nikmans Hattu ◽  
Ritti P. Sangadji ◽  
Risma Mahulette ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Content Analysis ◽  
Liquid Chromatography ◽  
Theobroma Cacao ◽  
High Performance ◽  
Measurement Methods ◽  
Caffeine Content ◽  
Rotary Evaporator ◽  
Theobroma Cacao L

Caffeine is a xanthine alkaloid compound found in Robusta sp and Theobroma cacao L. The caffeine extract was obtained by evaporating CHCl3 using a rotary evaporator and determine its content using iodometry, UV-Vis spectrophotometry and High Performance Liquid Chromatography, then validated by measurement methods. The iodometric caffeine content in Theobroma cacao L is 900 mg/kg while UV-Vis spectrophotometry is 4,000 mg/kg, and for HPLC in Robusta sp is 19,475 mg/kg. The iodometry performance gives the linearity value, R2 of 0.9791. The precision values at 5.0 mg/L and 15.0 mg/L are 4.6% and 8.3%. Accuracy for 5.0; 10.0; and 15.0 mg/L are 106%, 100% and 94% respectively. The performance of UV-Vis spectrophotometry gives linearity value, R2 of 0.9948. The precision value at 1.0 mg/L and 6.0 mg/L gives the variance coefficient value of 4.2% and 1.2%, while the accuracy at 1.0 mg/L and 6.0 mg/L are 99% and 101%.

scholarly journals Pharmacokinetics of Gatifloxacin and Interaction with an Antacid Containing Aluminum and Magnesium

1999 ◽  
Vol 43 (5) ◽  
pp. 1067-1071 ◽  
Author(s):  
Silke Lober ◽  
Susanne Ziege ◽  
Margot Rau ◽  
Gabriele Schreiber ◽  
Alain Mignot ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Standard Deviation ◽  
Crossover Study ◽  
Magnesium Hydroxide ◽  
Peak Concentration ◽  
High Performance ◽  
Area Under The Curve ◽  
Optimal Time ◽  
Comparison Of The Results

ABSTRACT The pharmacokinetics of gatifloxacin (400 mg orally) and the influence of the antacid aluminum magnesium hydroxide (20 ml of Maalox 70) on the bioavailability of gatifloxacin in 24 healthy volunteers were assessed. In an open, randomized, six-period crossover study, the volunteers received either gatifloxacin alone (treatments A and D); aluminum magnesium hydroxide concomitant with gatifloxacin (treatment C); or aluminum magnesium hydroxide 2 h before (treatment B), 2 h after (treatment E), or 4 h after gatifloxacin administration (treatment F). Gatifloxacin concentrations were measured by a validated bioassay and high-performance liquid chromatography. Pharmacokinetics of a single 400-mg dose of gatifloxacin alone were characterized as follows (mean ± standard deviation): peak concentration (C max), 3.8 ± 0.5 (treatment A) and 3.4 ± 0.9 (treatment D) μg/ml; time toC max, 1.4 ± 0.8 (treatment A) and 1.7 ± 0.7 (treatment D) h; area under the curve from time zero to infinity (AUC0–∞), 33.5 ± 5.9 (treatment A) and 31.4 ± 3.4 (treatment D) μg · h/ml; urine recovery, (83 ± 6)% (treatment A) and (84 ± 8)% (treatment D). Comparison of the results obtained by bioassay showed a good correlation. Aluminum magnesium hydroxide administration 2 h before (treatment B) or concomitant with (treatment C) gatifloxacin decreased the C max by 45% (2.1 ± 1.2 μg/ml) or even 68% (1.2 ± 0.4 μg/ml) highly significantly (P < 0.01). AUC0–∞ was significantly reduced from 33.5 ± 5.9 to 19.4 ± 6.9 μg · h/ml (by 42%) or even to 11.9 ± 3.3 μg · h/ml (by 64%) (P < 0.01). If aluminum magnesium hydroxide was given 2 h after gatifloxacin (treatment E), there was no significant reduction of concentration in serum but AUC0–∞ was significantly reduced from 31.4 ± 3.4 to 25.9 ± 5.3 μg · h/ml (18%) (P < 0.01). Aluminum magnesium hydroxide given 4 h after gatifloxacin (treatment F) showed no influence on the gatifloxacin pharmacokinetics. Therefore, the optimal time between gatifloxacin application and the intake of an aluminum-containing antacid should be 4 h.

scholarly journals Can Cold Brew Coffee Be Convenient? A Pilot Study For Caffeine Content in Cold Brew Coffee Concentrate Using High Performance Liquid Chromatography

2017 ◽  
Vol 8 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Sarah Lane ◽  
Josh Palmer ◽  
Brian Christie ◽  
Juergen Ehlting ◽  
Cuong Le
Keyword(s):  
Clinical Trials ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Extraction Methods ◽  
Preparation Methods ◽  
Caffeine Content ◽  
The Mean ◽  
Brewing Method ◽  
Mean Concentration

Cold brew coffee is a brewing method that is increasing in prevalence. While it has been anecdotally suggested that this method may provide a more aromatic and flavourful coffee product, there is little research published that looks at the concentration of caffeine or other coffee substituents in cold brew coffee. The potential alteration in chemical composition in cold brew provides a few interesting avenues for research. Can caffeine in cold brew be quantified by conventional methods? If so, how does the caffeine profile of cold brews relate to hot brew methods? Here we report the caffeine content and variability in small batch cold brew coffee and show that HPLC/UV-Vis, a standard method for quantitation of caffeine in other extraction methods, is useful for detection of caffeine in cold brew coffee. The mean concentration of caffeine in an average 355 mL serving was found to be 207.22 ± 39.17 mg over five distinct batches of cold brew coffee concentrate. Cold brew preparation methods produce similar quantities of caffeine as hot brew preparation, yet may have increased storage capabilities including improved retention of flavonoids and other secondary metabolites. Therefore, cold brew may provide utility in clinical trials examining caffeine and the effect of other components of coffee as it is commonly consumed.

scholarly journals Determination of Caffeine in Beverages Found in Bangladeshi Market by High Performance Liquid Chromatography (HPLC)

2021 ◽  
Vol 37 (3) ◽  
pp. 663-666
Author(s):  
G. M. M. Anwarul Hasan ◽  
Anuj Kumer Das
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Mobile Phase ◽  
High Performance ◽  
Energy Drinks ◽  
Soft Drinks ◽  
Caffeine Content

Caffeine, a phycostimulant is present in several foods and drinks.In the present study, beverages of different brands in Bangladeshi market were analyzed for caffeine by high-performance liquid chromatography (HPLC) using methanol-water (40:60, v/v) as mobile phase. Caffeine content ranged from 16.33 -19.33 mg/can in soft drinks and 45.66-47.33 mg/can in energy drinks respectively. These data indicated that the levels of caffeine in Bangladeshi soft drinks and energy drinks are within the ranges reported from similar products in other countries.

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