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Acta Alimentaria
Authors: E. Ivanišová, K. Meňhartová, M. Terentjeva, L. Godočíková, J. Árvay, and M. Kačániová

The aim of the present study was to determine the microbial composition, antioxidant activity, and content of phytochemicals in prepared kombucha tea beverage. Microbiota was identified by MALDI-TOF mass spectrometry, antioxidant activity of beverage was tested by ABTS and phosphomolybdenum method, the total content of phytochemicals (polyphenols, flavonoids, and phenolic acids) was measured by colorimetric methods. The major phenolic acids, flavonoids, and methylxanthines were detected by high performance liquid chromatography (HPLC). Candida krusei, Sphingomonas melonis, Sphingomonas aquatilis, Brevibacillus centrosporus, and Gluconobacter oxydans were the most abundant microorganisms. Antioxidant activity of kombucha tested by ABTS and phosphomolybdenum method was 1.16 mg TEAC/ml and 2.04 mg TEAC/ml, respectively, which values were higher than in black tea 0.67 and 0.81 mg TEAC/ml, respectively. Also, content of total polyphenols (0.42 mg GAE/ ml), flavonoids (0.13 mg QE/ml), and phenolic acids (0.19 mg CAE/ml) was higher in kombucha than in black tea (0.18 mg GAE/ml; 0.02 mg QE/ml; 0.05 mg CAE/ml, respectively). Gallic, chlorogenic, syringic, and protocatechuic acids, and rutin and vitexin from flavonoids were dominant in kombucha beverage detected by HPLC. Strong difference in caffeine contents, 217.81 µg ml−1 (black tea) and 100.72 µg ml−1 (kombucha beverage), was observed. The amounts of theobromine were similar in black tea and kombucha, but theophylline was detected only in black tea in trace amount (0.52 µg ml−1).

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Orvosi Hetilap
Authors: Katalin Vágási, Péter Degrell, István Késői, Tibor Kovács, István Pintér, Béla Molnár, Judit Cseh, Judit Nagy, and István Wittmann

Cannon, M. E., Cooke, C. T., McCarthy, J. S.: Caffeine-induced cardiac arrhytmia: an unrecognised danger of healthfood products. Med. J. Aust., 2001, 174 , 520–521. McCarthy J. S

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Thermal decomposition of methylxanthines

Interpretation of the results by PCA

Journal of Thermal Analysis and Calorimetry
Authors: M. Wesolowski and P. Szynkaruk

Abstract  

The thermal decomposition of theophylline, theobromine, caffeine, diprophylline and aminophylline were evaluated by calorimetrical, thermoanalytical and computational methods. Calorimetrical studies have been performed with aid of a heat flux Mettler Toledo DSC system. 10 mg samples were encapsulated in a 40 μL flat-bottomed aluminium pans. Measurements in the temperature range form 20 to 400°C were carried out at a heating rate of 10 and 20°C min−1 under an air stream. It has been established that the values of melting points, heat of transitions and enthalpy for methylxanthines under study varied with the increasing of heating rate. Thermoanalytical studies have been followed by using of a derivatograph. 50, 100 and 200 mg samples of the studied compounds were heated in a static air atmosphere at a heating rate of 3, 5, 10 and 15°C min−1 up to the final temperature of 800°C. By DTA, TG and DTG methods the influence of heating rate and sample size on thermal destruction of the studied methylxanthines has been determined. For chemometric evaluation of thermoanalytical results the principal component analysis (PCA) was applied. This method revealed that first of all the heating rate influences on the results of thermal decomposition. The most advantageous results can be obtained taking into account sample masses and heating rates located in the central part of the two-dimensional PCA graph. As a result, similar data could be obtained for 100 mg samples heated at 10°C·min−1 and for 200 mg samples heated at 5°C min−1.

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453 460 Smit, H. J., Cotton, J. R., Hughes, S. C. és mtsa: Mood and cognitive performance effects of „energy” drink constituents: caffeine, glucose and

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Orvosi Hetilap
Authors: Máté Magyar, Nóra Luca Nyilas, Dániel Bereczki, György Bozsik, Gábor Rudas, Csaba Ertsey, Pál Maurovich-Horvat, and Péter Barsi

Összefoglaló. A klasszikus esetben ortosztatikus fejfájást okozó, spontán intracranialis hypotensiót az esetek túlnyomó többségében a gerinccsatornában, annak nyaki-háti átmenetében, illetve a háti szakaszán található liquorszivárgás okozza. Meglévő kötőszöveti betegség, degeneratív gerincbetegségek, illetve kisebb traumák szerepet játszhatnak a szivárgás kialakulásában. Az ortosztatikus fejfájás létrejöttében szerepet játszhat a meningealis szerkezetek, érzőidegek és hídvénák vongálódása. A klasszikus pozicionális, ortosztatikus fejfájásban szenvedő betegek körében gondolni kell a spontán intracranialis hypotensio lehetőségére, és az agykoponya, illetve a gerinc kontrasztanyaggal végzett mágneses rezonanciás vizsgálata (MRI) javasolt. A kontrasztanyaggal végzett koponya-MRI-vel klasszikus esetben diffúz, nem nodularis, intenzív, vaskos pachymeningealis kontrasztanyag-halmozás, kitágult vénássinus-rendszer, subduralis effusiók és az agytörzs caudalis diszlokációja („slumping”) látható. Fontos azonban szem előtt tartani, hogy az esetek 20%-ában ezen eltérések nem detektálhatók. Jó minőségű, randomizált, kontrollált vizsgálatok nem történtek, a kezelés hagyományokon alapul. Kezdetben általában konzervatív terápiát alkalmaznak (ágynyugalom, koffein- és folyadékbevitel), ennek hatástalansága esetén epiduralis sajátvér-injekció, epiduralis fibrinragasztó-injektálás, illetve sebészi terápia jöhet szóba. Orv Hetil. 2021; 162(7): 246–251.

Summary. Spontaneous intracranial hypotension, the classic feature of which is orthostatic headache, is most commonly caused by a cerebrospinal fluid leakage at the level of the spinal canal, in most cases at the thoracic level or cervicothoracic junction. Underlying connective tissue disorders, minor trauma, degenerative spinal diseases may play a role in the development of cerebrospinal fluid leaks. Traction on pain-sensitive intracranial and meningeal structures, particularly sensory nerves and bridging veins, may play a role in the development of orthostatic headache. In the case of patients with classic orthostatic headache, the possibility of spontaneous intracranial hypotension should be considered, and if suspected, brain magnetic resonance imaging (MRI) with gadolinium and additional spine MRI are recommended. Diffuse, non-nodular, intense, thick dural enhancement, subdural effusions, engorgement of cerebral venous sinuses, sagging of the brain are typical features on brain MRI, which, however, remain normal in up to 20 percent of patients with spontaneous intracranial hypotension. Unfortunately, no randomized clinical trials have evaluated the effectiveness of the various treatment strategies and no definitive treatment protocols have been established. In clinical practice, the first-line treatment of spontaneous intracranial hypotension is conservative (bed rest, caffeine and fluid intake). If conservative therapy is not effective, epidural blood patch, epidural fibrin glue, or surgical repair should be considered. Orv Hetil. 2021; 162(7): 246–251.

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., Kumari, D., Freedman, J., Freedman, N. Chou, C. H. (1986): Caffeine autotoxicity in Coffea arabica. In: Putnam, A. R. Tang, C. S. (eds): The science of allelopathy. John Willey and Sons, N. Y., pp. 243

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Szeitz-Szabó, M., Biró, L., Biró, Gy. & Sali, J. (2011): Dietary survey in Hungary, 2009. Part I.: Macronutrients, alcohol, caffeine, fibre. Acta Alimentaria , 40 , 142–152. Sali J

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Szeitz-Szabó, M., Biró, L., Biró, Gy. & Sali, J. (2011): Dietary survey in Hungary, 2009. Part I. Macronutrients, alcohol, caffeine, fibre. Acta Alimentaria , 40 , 142–152. Sali J

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36 390 394 Sipiczki, M., Takeo, K.: The effect of caffeine on cell cycle progression and polar growth in Schizosaccharomyces pombe . Biologia

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foods which have surplus phosphorus or another ingredient (e.g., caffeine) promoting discharge of Ca from the body with Ca. For enrichment those food additives are suitable which contain Ca in a bioavailable form. Bioavailable is the part of the foods

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