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Journal articles on the topic 'Caffeine free'

Author: Grafiati

Published: 2 June 2025

Last updated: 31 July 2025

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1

Janiszewski, Michał, Marcin Komorowski, Rafał Kaczorowski, et al. "Brewed for Performance: Caffeine’s Impact on Nutrition, Endurance and Strength in Sports." Journal of Education, Health and Sport 77 (January 18, 2025): 56957. https://doi.org/10.12775/jehs.2025.77.56957.

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Caffeine is one of the most widely consumed and studied stimulants worldwide with a long history in athletics as a performance enhancer. Although listed as a stimulant in the World Anti-Doping Agency’s (WADA’s) 2024 Monitoring Program, its use is not prohibited. Individual responses to caffeine vary widely due to factors like genetics, age, and lifestyle habits, such as smoking and diet. This paper examines caffeine's multifaced role in human metabolism, with an emphasis on athletes' training (endurance and strength) and post-exercise recovery. Our comprehensive review of literature indicates

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2

&NA;. "Free Communication/Poster - Caffeine." Medicine & Science in Sports & Exercise 40, Supplement (2008): 58. http://dx.doi.org/10.1249/01.mss.0000321209.12034.10.

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3

Heytens, L., J. J. A. Heffron, and F. Camu. "The caffeine contracture test for malignant hyperthermia: caffeine citrate, caffeine benzoate or caffeine free base?" Acta Anaesthesiologica Scandinavica 35, no. 6 (1991): 541–44. http://dx.doi.org/10.1111/j.1399-6576.1991.tb03344.x.

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4

Hetzler, R. K., R. G. Knowlton, S. M. Somani, D. D. Brown, and R. M. Perkins. "Effect of paraxanthine on FFA mobilization after intravenous caffeine administration in humans." Journal of Applied Physiology 68, no. 1 (1990): 44–47. http://dx.doi.org/10.1152/jappl.1990.68.1.44.

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Because it has previously been shown that it takes much more caffeine to cause fat mobilization in vitro than in vivo, it has been suggested that there may be an active metabolite working with caffeine causing an increase in lipolysis in vivo. To determine the relationship between the appearance of paraxanthine (caffeine's major dimethylxanthine metabolite) and free fatty acid (FFA) mobilization after intravenous caffeine administration, 10 men were studied at rest after receiving a dose of 4 mg/kg lean body mass. Venous blood samples were obtained before dosing and at minutes 5, 10, 15, 30, 4

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5

Coelho, Margarida, Rita S. Patarrão, Inês Sousa-Lima, et al. "Increased Intake of Both Caffeine and Non-Caffeine Coffee Components Is Associated with Reduced NAFLD Severity in Subjects with Type 2 Diabetes." Nutrients 15, no. 1 (2022): 4. http://dx.doi.org/10.3390/nu15010004.

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Coffee may protect against non-alcoholic fatty liver disease (NAFLD), but the roles of the caffeine and non-caffeine components are unclear. Coffee intake by 156 overweight subjects (87% with Type-2-Diabetes, T2D) was assessed via a questionnaire, with 98 subjects (all T2D) also providing a 24 h urine sample for quantification of coffee metabolites by LC–MS/MS. NAFLD was characterized by the fatty liver index (FLI) and by Fibroscan® assessment of fibrosis. No associations were found between self-reported coffee intake and NAFLD parameters; however, total urine caffeine metabolites, defined as

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6

Cheek, T. R., V. A. Barry, M. J. Berridge, and L. Missiaen. "Bovine adrenal chromaffin cells contain an inositol 1,4,5-trisphosphate-insensitive but caffeine-sensitive Ca2+ store that can be regulated by intraluminal free Ca2+." Biochemical Journal 275, no. 3 (1991): 697–701. http://dx.doi.org/10.1042/bj2750697.

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We have characterized some properties of the caffeine-sensitive Ca2+ store in bovine chromaffin cells. Addition of 10 mM-caffeine to permeabilized cells that were allowed to sequester Ca2+ in the presence of the precipitating anion pyrophosphate induced a transient rise in free Ca2+ concentration that was blocked by 10 microM-Ruthenium Red. Caffeine was able to release Ca2+ after the InsP3-sensitive Ca2+ pool had been completely emptied, and 10 microM-InsP3 still released Ca2+ in the presence of a high dose (50 mM) of caffeine, indicating that there are selectively sensitive Ca2+ pools in thes

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7

Meliska, Charles J., and Christopher F. Lawson. "Effects of Caffeine-and Sugar-Free Beverages on Psychomotor Performance." Perceptual and Motor Skills 82, no. 3 (1996): 912–14. http://dx.doi.org/10.2466/pms.1996.82.3.912.

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8

Hassan, Amir, Muhammad Ashfaq, Ali Khan, and Muhammad Shakeel Khan. "Isolation of Caffeine from Carbonated Beverages." Journal of Tropical Pharmacy and Chemistry 5, no. 1 (2020): 33–38. http://dx.doi.org/10.25026/jtpc.v5i1.234.

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The work presented on the isolation of naturally occurring alkaloid from carbonated beverages. The extensive presence of caffeine in different plants plays an important role in the long-standing acceptance of caffeine-containing products. Caffeine (3,7-dihydro-1, 3,7-trimethyl-1H-purine-2,6-dione or 1,3,7-trimethylxanthine) is an alkaloid belongs to Methylxanthine family. Liquid-liquid extraction methods were used in the assay of research work. Chloroform was taken as extracting solvent. Solid residue of caffeine was recrystallized from 95% ethanol using 5ml/gram (5ml per gram). It is declared

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Baumann, Thomas W. "Revisiting Caffeine Biosynthesis – Speculations about the Proximate Source of its Purine Ring." Natural Product Communications 10, no. 5 (2015): 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000523.

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The prevailing hypothesis of caffeine biosynthesis starting from xanthosine was combined with Kremers’ speculation on NAD as a biochemical precursor of caffeine and trigonelline in coffee. This bold sketch together with a few free-spirited ideas may channel future caffeine biosynthesis studies into novel directions.

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10

Ashihara, Hiroshi, Hisayo Shimizu, Yoshiyuki Takeda, Takeo Suzuki, Fiona M. Gillies, and Alan Crozier. "Caffeine Metabolism in High and Low Caffeine Containing Cultivars of Camellia sinensis." Zeitschrift für Naturforschung C 50, no. 9-10 (1995): 602–7. http://dx.doi.org/10.1515/znc-1995-9-1002.

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Abstract The metabolism of [8-14C ]adenine and [2-14C]caffeine was examined in leaf segments from flush shoots of tea cultivars with high and low caffeine content. The caffeine biosynthesis pathway from AMP via theobromine was operative in both high and low caffeine containing cultivars. There was a m ore rapid rate of caffeine biosynthesis from [8-14C ]adenine in the high caffeine cultivars while the rate of degradation of both adenine nucleotides and caffeine into CO2 was greatest in cultivars with a low endogenous caffeine content. Cell-free p reparations from tea shoots contained an N-meth

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11

Van Soeren, M. H., and T. E. Graham. "Effect of caffeine on metabolism, exercise endurance, and catecholamine responses after withdrawal." Journal of Applied Physiology 85, no. 4 (1998): 1493–501. http://dx.doi.org/10.1152/jappl.1998.85.4.1493.

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In this study the effects of acute caffeine ingestion on exercise performance, hormonal (epinephrine, norepinephrine, insulin), and metabolic (free fatty acids, glycerol, glucose, lactate, expired gases) parameters during short-term withdrawal from dietary caffeine were investigated. Recreational athletes who were habitual caffeine users ( n = 6) (maximum oxygen uptake 54.5 ± 3.3 ml ⋅ kg−1 ⋅ min−1and daily caffeine intake 761.3 ± 11.8 mg/day) were tested under conditions of no withdrawal and 2-day and 4-day withdrawal from dietary caffeine. There were seven trials in total with a minimum of 10

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12

Poehlman, Eric T., Pierre LaChance, Angelo Tremblay, et al. "The effect of prior exercise and caffeine ingestion on metabolic rate and hormones in young adult males." Canadian Journal of Physiology and Pharmacology 67, no. 1 (1989): 10–16. http://dx.doi.org/10.1139/y89-003.

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The purposes of this study were to examine (a) the effects of acute exercise on metabolic rate 24 and 48 h postexercise and (b) the interaction of acute exercise and the thermic effect of caffeine on metabolic rate and hormonal changes during the late postexercise recovery period. In six young males, who were regular consumers of caffeine, resting energy expenditure was measured before and after caffeine (5 mg∙kg−1) and placebo ingestion under the following conditions: (i) control (e.g., no prior exercise), (ii) 24 h postexercise, and (iii) 48 h postexercise. Blood samples were drawn for plasm

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13

Yamamoto, H., and C. van Breemen. "Ca2+ compartments in saponin-skinned cultured vascular smooth muscle cells." Journal of General Physiology 87, no. 3 (1986): 369–89. http://dx.doi.org/10.1085/jgp.87.3.369.

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A method for saponin skinning of primary cultured rat aortic smooth muscle cells was established. The saponin-treated cells could be stained with trypan blue and incorporated more 45Ca2+ than the nontreated cells under the same conditions. At low free Ca2+ concentration, greater than 85% of 45Ca2+ uptake into the skinned cells was dependent on the extracellularly supplied MgATP. In the intact cells, both caffeine and norepinephrine increased 45Ca2+ efflux. In the skinned cells, caffeine increased 45Ca2+ efflux, whereas norepinephrine did not. The caffeine-releasable 45Ca2+ uptake fraction in t

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14

Hasselbach, Wilhelm, and Andrea Migala. "How Many Ryanodine Binding Sites Are Involved in Caffeine Induced Calcium Release from Sarcoplasmic Reticulum Terminal Cysternae Vesicles?" Zeitschrift für Naturforschung C 47, no. 1-2 (1992): 136–47. http://dx.doi.org/10.1515/znc-1992-1-223.

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Abstract The inhibition by ryanodine of caffeine induced calcium release from actively loaded heavy sarcoplasmic vesicles has been studied in order to analyse the relation between the occupancy of the vesicular calcium release channels by ryanodine and channel function. Ryanodine binding was monitored with [3H]ryanodine under ionic conditions favouring the establishment of binding equilibrium. Binding follows 1 : 1 stoichiometry yielding dissociations constants between 7 - 12 nᴍ and 12-15 pmol ryanodine/mg vesicular protein as maximum number of ryanodine binding sites. When ryanodine labeling

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15

Graham, T. E., P. Sathasivam, and K. W. MacNaughton. "Influence of cold, exercise, and caffeine on catecholamines and metabolism in men." Journal of Applied Physiology 70, no. 5 (1991): 2052–58. http://dx.doi.org/10.1152/jappl.1991.70.5.2052.

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Recently we found that caffeine ingestion did not enhance either thermal or fat metabolic responses to resting in cold air, despite an increase in plasma epinephrine and free fatty acids. Theophylline, another methylxanthine, has been shown to be effective during exercise but not at rest during cold stress. Therefore we hypothesized that caffeine ingestion before exercise in cold air would have a thermal-metabolic impact by increasing fat metabolism and increasing oxygen consumption. Young adult men (n = 6) who did not normally have caffeine in their diet performed four double-blind trials. Th

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16

STOFFELEN, PIET, MICHEL NOIROT, EMMANUEL COUTURON, and FRANÇOIS ANTHONY. "A new caffeine-free coffee from Cameroon." Botanical Journal of the Linnean Society 158, no. 1 (2008): 67–72. http://dx.doi.org/10.1111/j.1095-8339.2008.00845.x.

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17

Al-Askari, Galal Ahmed, Mushtaq Faisal Al-Afour, Ismaeel Mohammed AL-Monsef, Abdullah Saleh AAl-Sanabani, and Ali Mansour Sinnan. "Chemical Composition Study of Three Varieties of Date seeds (Iraqi, Saudi and Yemeni) and their Utilization as caffeine-free coffee alternative." Journal of Chemistry and Nutritional Biochemistry 5, no. 1 (2024): 1–11. http://dx.doi.org/10.48185/jcnb.v5i1.1079.

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The study aimed to investigate the chemical composition of three widely available types of date seed in the Yemeni market (Iraqi, Saudi, and Yemeni) and their potential use as caffeine-free coffee alternative. Quantitative estimation was conducted for moisture, ash, protein, fiber, fat, carbohydrates, and caffeine, along with a descriptive estimation for alkaloids, tannins, and resins. Date seed coffee was prepared and sensory evaluation was performed by trained panelists. The results showed that Yemeni date seeds had the highest extraction Rate on average (30%), while Saudi date seeds had hig

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18

Winston, Anthony P., Elizabeth Hardwick, and Neema Jaberi. "Neuropsychiatric effects of caffeine." Advances in Psychiatric Treatment 11, no. 6 (2005): 432–39. http://dx.doi.org/10.1192/apt.11.6.432.

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Psychiatrists rarely enquire about caffeine intake when assessing patients. This may lead to a failure to identify caffeine-related problems and offer appropriate interventions. Excessive caffeine ingestion leads to symptoms that overlap with those of many psychiatric disorders. Caffeine is implicated in the exacerbation of anxiety and sleep disorders, and people with eating disorders often misuse it. It antagonises adenosine receptors, which may potentiate dopaminergic activity and exacerbate psychosis. In psychiatric in-patients, caffeine has been found to increase anxiety, hostility and psy

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19

Graham, T. E., and L. L. Spriet. "Metabolic, catecholamine, and exercise performance responses to various doses of caffeine." Journal of Applied Physiology 78, no. 3 (1995): 867–74. http://dx.doi.org/10.1152/jappl.1995.78.3.867.

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This study examined the exercise responses of well-trained endurance athletes to various doses of caffeine to evaluate the impact of the drug on exercise metabolism and endurance capacity. Subjects (n = 8) withdrew from all dietary sources of caffeine for 48 h before each of four tests. One hour before exercise they ingested capsules of placebo or caffeine (3, 6, or 9 mg/kg), rested quietly, and then ran at 85% of maximal O2 consumption to voluntary exhaustion. Blood samples for methylxanthine, catecholamine, glucose, lactate, free fatty acid, and glycerol analyses were taken every 15 min. Pla

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20

Lazić, Anja, Miodrag Kocić, Nebojša Trajković, Cristian Popa, Leonardo Alexandre Peyré-Tartaruga, and Johnny Padulo. "Acute Effects of Caffeine on Overall Performance in Basketball Players—A Systematic Review." Nutrients 14, no. 9 (2022): 1930. http://dx.doi.org/10.3390/nu14091930.

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Caffeine supplementation has become increasingly popular among athletes. The benefits of caffeine include delaying the negative effects of fatigue, maintaining a high level of physical and mental performance, and improving certain abilities necessary for sport success. Given the complex nature of basketball, caffeine could be a legal, ergogenic stimulant substance, which will positively affect overall basketball performance. The purpose of this systematic review was to summarize evidence for the effect of acute caffeine ingestion on variables related to the basketball performance. Web of Scien

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21

Lafontant, Kworweinski, Jacob Broeckel, Kara Phillips, et al. "The Acute Effects of a Commercially Available Caffeinated and Caffeine-Free Thermogenic Dietary Supplement on Resting Energy Expenditure, Hunger, and Hemodynamic Responses." Nutraceuticals 4, no. 1 (2024): 82–93. http://dx.doi.org/10.3390/nutraceuticals4010006.

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There has been a rise in popularity of “stimulant-free” or caffeine-free fat loss supplements, but it is not well understood whether those fat loss supplements are effective at enhancing thermogenesis without caffeine’s influence. The purpose of this study was to examine the effects of a caffeinated and non-caffeinated commercially available fat loss supplement on resting energy expenditure (REE), hunger, and hemodynamic variables in healthy adults. Twenty-five healthy male and female participants completed three separate laboratory visits after overnight fasts. Baseline assessments of REE, su

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22

Franzini, C., and G. Cattozzo. "Caffeine-splitting of bilirubin/albumin complex: its relevance to the spectrophotometry of bilirubin in serum." Clinical Chemistry 33, no. 4 (1987): 597–99. http://dx.doi.org/10.1093/clinchem/33.4.597.

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Abstract By means of gel-filtration of bilirubin/albumin mixtures, it is shown that unconjugated bilirubin remains completely linked to albumin (both human and bovine) in tetraborate buffer (pH 9.3), protein-free bilirubin appearing only when the bilirubin/albumin molar ratio exceeds two. On the other hand, bilirubin is completely set free from its protein link in the caffeine reagent. Additional chromatographic and spectrophotometric evidence is reported indicating the formation of a low-affinity complex between bilirubin and caffeine. These data explain why the spectrophotometric properties

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23

Mohd Jamil, Nor Azreen, Jameel Al-Obaidi, Norihan Mohd Saleh, and Nuzul Noorahya Jambari. "Comparative nutritional and toxicity analyses of beverages from date seed and barley powders as caffeine-free coffee alternatives." International Food Research Journal 29, no. 4 (2022): 786–95. http://dx.doi.org/10.47836/ifrj.29.4.06.

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Coffee is one of the most preferred beverages due to its flavour and aroma, which is partially contributed by the presence of caffeine. However, there are many negative effects of caffeine on human health. Alternative products like date seed and barley beverage have become an interest to switch from caffeine to caffeine-free beverages. The present work thus aimed to evaluate the nutritional properties and toxicity of date seed and barley powders as compared to Arabica coffee powder. Samples were analysed for its caffeine content, antioxidant activity, and toxicity activity from boiled water ex

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Bers, D. M. "Ryanodine and the calcium content of cardiac SR assessed by caffeine and rapid cooling contractures." American Journal of Physiology-Cell Physiology 253, no. 3 (1987): C408—C415. http://dx.doi.org/10.1152/ajpcell.1987.253.3.c408.

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The ability of rabbit ventricular muscle sarcoplasmic reticulum (SR) to accumulate and retain Ca during Na-free perfusion was assessed using caffeine contractures and rapid cooling contractures (RCC). Muscles were exposed to a Na-free medium for 15 min, during which time a transient contracture developed and relaxed back to the resting tension level. Muscles were then either exposed to 20 mM caffeine or rapidly cooled to less than 5 degrees C, both of which produced large contractures. The magnitudes of those contractures are believed to be a relative index of SR Ca content. Reduction of extra

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25

Graier, W. F., S. Simecek, D. K. Bowles, and M. Sturek. "Heterogeneity of caffeine- and bradykinin-sensitive Ca2+ stores in vascular endothelial cells." Biochemical Journal 300, no. 3 (1994): 637–41. http://dx.doi.org/10.1042/bj3000637.

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The filling state of Ca2+ stores in endothelial cells regulates Ca2+ entry. The functional relationship between the major Ca2+ stores [i.e. Ins(1,4,5)P3-sensitive (= bradykinin-sensitive stores, ‘BsS’) and caffeine-sensitive stores] is unknown. In pig right-coronary-artery endothelial cells, caffeine failed to release Ca2+ in 68% of the cells (quiet-responders), but increased bradykinin (Bk)-induced Ca2+ release 2.5-fold. In Bk-pre-stimulated cells, caffeine increased Ca2+ release upon a second stimulation with Bk 3.2-fold. In quiet-responders caffeine alone did not affect net Ca2+ storage, wh

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Peng, Xianglu, Melanie Brown, Paul Bowdler, and Kevin C. Honeychurch. "Extraction-Free, Direct Determination of Caffeine in Microliter Volumes of Beverages by Thermal Desorption-Gas Chromatography Mass Spectrometry." International Journal of Analytical Chemistry 2020 (April 1, 2020): 1–7. http://dx.doi.org/10.1155/2020/5405184.

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An extraction-free method requiring microliter (μL) volumes has been developed for the determination of caffeine in beverages. Using a pyrolysis-gas chromatography mass spectrometry system, the conditions required for the direct thermal desorption-gas chromatography mass spectrometry (TD-GC/MS) determination of caffeine were optimised. A 5 μL aliquot was introduced to the thermal desorption unit, dried, and thermally desorbed to the GC/MS. The response was linear over the range 10 to 500 μg/mL (R2 = 0.996). The theoretical limit of detection (3 σ) was 0.456 μg/mL. No interferences were recorde

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Duke, Adrian M., and Derek S. Steele. "Mechanisms of reduced SR Ca2+ release induced by inorganic phosphate in rat skeletal muscle fibers." American Journal of Physiology-Cell Physiology 281, no. 2 (2001): C418—C429. http://dx.doi.org/10.1152/ajpcell.2001.281.2.c418.

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The effects of inorganic phosphate (Pi) on Ca2+ release from the sarcoplasmic reticulum (SR) were studied in mechanically skinned rat skeletal muscle fibers. Application of caffeine or T-tubule depolarization was used to induce Ca2+ release from the SR, which was detected using fura 2 fluorescence. Addition of Pi (1–40 mM) caused a reversible and concentration-dependent reduction in the caffeine-induced Ca2+ transient. This effect was apparent at low Pi concentration (<5 mM), which did not result in detectable precipitation of calcium phosphate within the SR. The inhibitory effect of Pi exh

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Prakash, Raj, Shafeeque Kunhiabdullah, and Medhat Ezzat. "To Caffeinate or Not to Caffeinate? The Dilemma in Neonatal Apnea Management." Journal of Clinical Neonatology 13, no. 4 (2024): 162–67. http://dx.doi.org/10.4103/jcn.jcn_55_24.

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Caffeine, a widely used central nervous system stimulant, has emerged as the most commonly used therapeutic agent for managing apnea of prematurity in neonates over the last decade. Despite the evidence favoring caffeine, there are several controversies with the use of caffeine in neonates. Several studies have shown that caffeine significantly decreases cerebral blood flow velocity, impacting cerebral oxygenation and tissue oxygenation index. Higher doses of caffeine have raised safety concerns, with reports of increased incidence of cerebellar hemorrhage and adverse neurological outcomes in

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Ibrahim Hamadamin, Shireen. "Effect of the dried limes (Citrus aurantifolia) on the caffeine kinetic extraction in black tea leaves (kinetic and thermodynamic study)." Bulletin of the Chemical Society of Ethiopia 36, no. 3 (2022): 697–705. http://dx.doi.org/10.4314/bcse.v36i3.18.

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ABSTRACT. The kinetic and thermodynamic parameters were studied for the extraction of caffeine in black tea leaves and tea leaves containing antioxidant dried limes (Citrus aurantifolia). Caffeine is widely used in human consumption and is present in any liquid suitable for drinking except water. However, the health and environmental demerits make it significant to reduce caffeine to much less concentration or decaffeination. Therefore, the effect of the dried antioxidant Citrus aurantifolia on caffeine concentration followed by pseudo-first-order reaction, kinetic parameters (pseudo-first-ord

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Fiala, Kelly A., Douglas J. Casa, and Melissa W. Roti. "Rehydration with a Caffeinated Beverage during the Nonexercise Periods of 3 Consecutive Days of 2-a-Day Practices." International Journal of Sport Nutrition and Exercise Metabolism 14, no. 4 (2004): 419–29. http://dx.doi.org/10.1123/ijsnem.14.4.419.

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The purpose of this study was to assess the influence of rehydration with a caffeinated beverage during non exercise periods on hydration status throughout consecutive practices in the heat. Ten (7 women, 3 men) partially heat-acclimated athletes (age 24 ± ly, body fat 19.2 ± 2%, weight 68.4 ± 4.0 kg, height 170 ± 3 cm) completed 3 successive days of 2-a-day practices (2 h/ practice, 4 h/d) in mild heat (WBGT = 23 °C). The 2 trials (double-blind, random, cross-over design) included; 1) caffeine (CAF) rehydrated with Coca-Cola® and 2) caffeine-free (CF) rehydrated with Caffeine-Free Coca-Cola®.

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Seo, Byung Jin, and Byung Seop Yoon. "The Effects of Aerobic and Resistant Exerciseon on Women’s Body Composition by Age: The Moderating Effects of Caffeine Intake and Nutritional Restrictions." Korean Society of Culture and Convergence 45, no. 8 (2023): 1227–40. http://dx.doi.org/10.33645/cnc.2023.08.45.08.1227.

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The purpose of this study is to analyze changes in body composition by age group when women combine caffeine intake, nutritional restrictions, caffeine intake and nutritional restrictions while doing aerobic and resistance exercises. As a result, women in their 40s and 50s lost more weight, fat free mass, body fat, and BMI than women in their 30s. However, in the analysis of variance, there was no significant difference for each variable 12 weeks before exercise and 12 weeks after exercise. In addition, as a result of examining the interaction effects of caffeine intake and nutritional restric

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Malaluan, Yanna Ehra Santina M., Gabriel L. Ortiz, Althea Swane T. Sykimte, Renos Khen O. Tuanda, Zyr Y. Urbiztondo, and Jade Stephanie B. Cerezo. "Potential of Talisay Seeds (Terminalia catappa) as an Alternative Coffee." Cognizance Journal of Multidisciplinary Studies 5, no. 5 (2025): 242–57. https://doi.org/10.47760/cognizance.2025.v05i05.015.

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This study investigated the potential of Talisay (Terminalia catappa) seeds as an alternative coffee by evaluating their physicochemical properties and sensory attributes. The research utilized a quantitative descriptive approach to assess the overall acceptability of Talisay seed coffee in terms of appearance, aroma, texture, taste, and nutritional composition. A Hedonic Rating Scale and Descriptive Rating Test Were employed to gather consumer preferences. At the same time, laboratory testing analyzed its pH level, moisture content, crude protein, crude fiber, crude fat, ash, carbohydrates, a

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Yanna, Ehra Santina M. Malaluan, L. Ortiz Gabriel, Swane T. Sykimte Althea, Khen O. Tuanda Renos, Y. Urbiztondo Zyr, and Stephanie B. Cerezo Jade. "Potential of Talisay Seeds (Terminalia catappa) as an Alternative Coffee." Cognizance Journal of Multidisciplinary Studies (CJMS) 5, no. 5 (2025): 242–57. https://doi.org/10.47760/cognizance.2025.v05i05.015.

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This study investigated the potential of Talisay (Terminalia catappa) seeds as an alternative coffee by evaluating their physicochemical properties and sensory attributes. The research utilized a quantitative descriptive approach to assess the overall acceptability of Talisay seed coffee in terms of appearance, aroma, texture, taste, and nutritional composition. A Hedonic Rating Scale and Descriptive Rating Test Were employed to gather consumer preferences. At the same time, laboratory testing analyzed its pH level, moisture content, crude protein, crude fiber, crude fat, ash, carbohydrates, a

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34

Dyab, Ayman, S., Alla, T. M. El Kady, and Amira A. Abdallah. "Evaluation of Caffeine-Free and Low-Caffeine Coffee Alternatives Prepared from Saidi Date Seeds." Food Technology Research Journal 6, no. 2 (2024): 149–65. https://doi.org/10.21608/ftrj.2024.420712.

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Trice, Isaiah, and Emily M. Haymes. "Effects of Caffeine Ingestion on Exercise-induced Change during High-Intensity Intermittent Exercise." International Journal of Sport Nutrition 5, no. 1 (1995): 37–44. http://dx.doi.org/10.1123/ijsn.5.1.37.

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In this study a double-blind design was used to determine the effect of caffeine on time to exhaustion and on associated metabolic and circulatory measures. Eight male subjects ingested either caffeine (5 mg/kg body weight) or a placebo 1 hr prior to exercise at 85-90% of maximum workload. Subjects were encouraged to complete three 30-min intermittent cycling periods at 70 rpm with 5 min rest between each. The exercise was terminated when the subject failed to complete three 30-min periods or failed to maintain 70 rpm for at least 15 s consecutively. Serum free fatty acids, glycerol, blood glu

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Graham, M. K., J. G. McGeown, and I. Fairweather. "Ionic mechanisms underlying spontaneous muscle contractions in the liver fluke, Fasciola hepatica." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 277, no. 2 (1999): R374—R383. http://dx.doi.org/10.1152/ajpregu.1999.277.2.r374.

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Spontaneous contractions of liver fluke muscle were abolished in Ca2+-free saline and by 100 μM nifedipine and reduced by 5 mM cadmium chloride, suggesting that they are dependent on extracellular Ca2+. Caffeine (5 mM) significantly increased contraction amplitude and frequency. Ryanodine (100 μM) failed to block the caffeine response but significantly reduced spontaneous contraction frequency, suggesting that intracellular stores have a functional role. Cyclopiazonic acid (5 μM) had no effect on the caffeine response or spontaneous activity. 3-Isobutyl-1-methylxanthine (IBMX), forskolin, and

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Júdice, Pedro B., João P. Magalhães, Diana A. Santos, et al. "A moderate dose of caffeine ingestion does not change energy expenditure but decreases sleep time in physically active males: a double-blind randomized controlled trial." Applied Physiology, Nutrition, and Metabolism 38, no. 1 (2013): 49–56. http://dx.doi.org/10.1139/apnm-2012-0145.

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Research on the effect of caffeine on energy expenditure (EE), physical activity (PA), and total sleep time (TST) during free-living conditions using objective measures is scarce. We aimed to determine the impact of a moderate dose of caffeine on TST, resting EE (REE), physical activity EE (PAEE), total EE (TEE), and daily time spent in sedentary, light, moderate, and vigorous intensity activities in a 4-day period and the acute effects on heart rate (HR) and EE in physically active males. Using a double-blind crossover trial (ClinicalTrials.gov ID: NCT01477294) with two conditions (4 days eac

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Anderson, Megan E., Clinton R. Bruce, Steve F. Fraser, et al. "Improved 2000-Meter Rowing Performance in Competitive Oarswomen after Caffeine Ingestion." International Journal of Sport Nutrition and Exercise Metabolism 10, no. 4 (2000): 464–75. http://dx.doi.org/10.1123/ijsnem.10.4.464.

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Eight competitive oarswomen (age, 22 ± 3 years; mass, 64.4 ± 3.8 kg) performed three simulated 2,000-m time trials on a rowing ergometer. The trials, which were preceded by a 24-hour dietary and training control and 72 hours of caffeine abstinence, were condueted 1 hour after ingesting caffeine (6 or 9 mg kg ’ body mass) or placebo. Plasma free fatty acid concentrations before exercise were higher with caffeine than placebo (0.67 ± 0.34 vs. 0.72 ± 0.36 vs. 0.30±0.10 mM for 6 and 9 mg · kg−1; caffeine and placebo, respectively; p <.05). Performance lime improved 0.7% (95% confidence interval

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Hetzler, R. K., N. Warhaftig-Glynn, D. L. Thompson, E. Dowling, and A. Weltman. "Effects of acute caffeine withdrawal on habituated male runners." Journal of Applied Physiology 76, no. 3 (1994): 1043–48. http://dx.doi.org/10.1152/jappl.1994.76.3.1043.

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This study investigated the effects of caffeine withdrawal on six trained caffeine-habituated male runners: age 29.8 +/- 5.8 (SD) yr, height 180.4 +/- 5.4 cm, weight 77.3 +/- 6.7 kg, maximal O2 uptake 63.0 +/- 5.4 ml.kg-1.min-1, and daily caffeine intake 674 +/- 128 mg. The subjects received a loading dose (5 mg/kg body wt) of caffeine 48 h before each testing session. They were then given (using a repeated-measures double-blind design) additional doses of caffeine (5 mg/kg body wt) or a placebo 36, 24, 12, and 2 h before testing. They ran at a velocity corresponding to their lactate threshold

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Shanahan, M. P., and R. N. Hughes. "Potentiation of Performance-Induced Anxiety by Caffeine in Coffee." Psychological Reports 59, no. 1 (1986): 83–86. http://dx.doi.org/10.2466/pr0.1986.59.1.83.

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46 student volunteers were confronted with a stressful or nonstressful task following ingestion of coffee that was either heavily caffeinated or relatively caffeine-free. State anxiety was increased by exposure to the stressful situation. However, this effect was greater in subjects who had ingested high caffeine-content coffee.

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WATSON, J. M., R. S. SHERWIN, I. J. DEARY, L. SCOTT, and D. KERR. "Dissociation of augmented physiological, hormonal and cognitive responses to hypoglycaemia with sustained caffeine use." Clinical Science 104, no. 4 (2003): 447–54. http://dx.doi.org/10.1042/cs1040447.

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In patients with Type I diabetes and healthy volunteers, ingestion of modest amounts of caffeine augments the usual symptomatic and counter-regulatory responses to hypoglycaemia. The aim of the present study was to determine whether these are lost with sustained caffeine use, i.e. does tolerance develop? Eleven healthy caffeine consumers underwent two identical hyperinsulinaemic glucose clamp procedures. For 7 days prior to each clamp, subjects consumed a caffeine-free diet supplemented with 200mg of caffeine capsules twice daily (caffeine-replete) or placebo (caffeine-withdrawn). During each

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Jayanti, Gatra Ervi, Sri Widyarti, Akhmad Sabarudin, and Sutiman Bambang Sumitro. "EGG WHITE ALBUMIN FORM COMPLEX WITH ASPIRIN AND CAFFEINE AND ITS ROLE AS FREE RADICAL SCAVENGER." Asian Journal of Pharmaceutical and Clinical Research 11, no. 7 (2018): 340. http://dx.doi.org/10.22159/ajpcr.2018.v11i7.25440.

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Objective: Egg white protein (ovalbumin) is well known to be freshly consumed in Indonesia as traditional medicine, or it is usually known as “Jamu.” Ovalbumin, as well as egg white albumin, is able to form complex compounds with other substances through the formation of weak chemical and physical bonds. The objective of this study is to understand the behavior of ovalbumin as radical scavenger when it binds to antioxidants such as aspirin and caffeine (as a complex). Methods: In this study, docking sites and ovalbumin as scavenger were studied using computer-modeling software. An ovalbumin wa

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Yadav, Sudesh Kumar, and Paramvir Singh Ahuja. "Towards Generating Caffeine-free Tea by Metabolic Engineering." Plant Foods for Human Nutrition 62, no. 4 (2007): 185–91. http://dx.doi.org/10.1007/s11130-007-0060-x.

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Nelson, Ashley M., Sean T. Hemp, Jessica Chau, and Timothy E. Long. "Free radical polymerization of caffeine-containing methacrylate monomers." Journal of Polymer Science Part A: Polymer Chemistry 53, no. 24 (2015): 2829–37. http://dx.doi.org/10.1002/pola.27756.

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Pascua, Stephanie M., Gabrielle E. McGahey, Ning Ma, Justin J. Wang, and Michelle A. Digman. "Caffeine and Cisplatin Effectively Targets the Metabolism of a Triple-Negative Breast Cancer Cell Line Assessed via Phasor-FLIM." International Journal of Molecular Sciences 21, no. 7 (2020): 2443. http://dx.doi.org/10.3390/ijms21072443.

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Triple-negative tumor cells, a malignant subtype of breast cancer, lack a biologically targeted therapy. Given its DNA repair inhibiting properties, caffeine has been shown to enhance the effectiveness of specific tumor chemotherapies. In this work, we have investigated the effects of caffeine, cisplatin, and a combination of the two as potential treatments in energy metabolism for three cell lines, triple-negative breast cancer (MDA-MB-231), estrogen-receptor lacking breast cancer (MCF7) and breast epithelial cells (MCF10A) using a sensitive label-free approach, phasor-fluorescence lifetime i

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Vogler, Arnd, Birgit Hischa, and Sabine Stempfhuber. "Synthesis, crystal structure and photoluminescence of the salts Cation+ [M(caffeine)Cl]− with Cation+=NnBu4+, AsPh4+ and M==Zn(II), Pt(II)." Zeitschrift für Naturforschung B 74, no. 11-12 (2019): 885–89. http://dx.doi.org/10.1515/znb-2019-0141.

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AbstractThe salts (NnBu4)[Zn(caffeine)Cl3] and (AsPh4)[Pt(caffeine)Cl3] were prepared and their crystal structures determined by single crystal X-ray diffraction. The free ligand caffeine, as well as the complex anions [M(II)(caffeine)Cl3]− with M = Zn and Pt show an absorption spectrum with an intense band at λmax = 275 nm, which is attributed to an IL π–π* transition of the caffeine. A second band at ca. 300 nm is much weaker and largely obscured by the π–π* band. This second band is assigned to an IL n–π* transition. Both complex anions exhibit a photoluminescence (fluorescence), which orig

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Burkhardt, Mark R., Paul P. Soliven, Stephen L. Werner, and Deborah G. Vaught. "Determination of Submicrogram-per-Liter Concentrations of Caffeine in Surface Water and Groundwater Samples by Solid-Phase Extraction and Liquid Chromatography." Journal of AOAC INTERNATIONAL 82, no. 1 (1999): 161–66. http://dx.doi.org/10.1093/jaoac/82.1.161.

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Abstract A method for determining submicrogram-per-liter concentrations of caffeine in surface water and groundwater samples has been developed. Caffeine is extracted from a 1 L water sample with a 0.5 g graphitized carbon-based solid-phase cartridge, eluted with methylene chloride-methanol (80 + 20, v/v), and analyzed by liquid chromatography with photodiode-array detection. The single-operator method detection limit for organic-free water samples was 0.02 μg/L. Mean recoveries and relative standard deviations were 93 ± 13% for organic- free water samples fortified at 0.04 μg/L and 84 ± 4% fo

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Akata, Takashi, and Walter A. Boyle. "Dual Actions of Halothane on Intracellular Calcium Stores of Vascular Smooth Muscle." Anesthesiology 84, no. 3 (1996): 580–95. http://dx.doi.org/10.1097/00000542-199603000-00014.

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Background Halothane has been reported to affect the integrity of intracellular Ca2+ stores in a number of tissues including vascular smooth muscle. However, the actions of halothane on intracellular Ca2+ stores are not yet fully understood. Methods Employing the isometric tension recording method, the action of halothane in isolated endothelium-denuded rat mesenteric arteries under either intact or beta-escinmembrane-permeabilized conditions was investigated. Results Halothane (0.125-5%) produced concentration-dependent contractions in Ca2+ free solution in both intact and membrane-permeabili

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Larsson, Susanna C., Benjamin Woolf, and Dipender Gill. "Appraisal of the causal effect of plasma caffeine on adiposity, type 2 diabetes, and cardiovascular disease: two sample mendelian randomisation study." BMJ Medicine 2, no. 1 (2023): 1–8. http://dx.doi.org/10.1136/bmjmed-2022-000335.

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ObjectiveTo investigate the potential causal effects of long term plasma caffeine concentrations on adiposity, type 2 diabetes, and major cardiovascular diseases.DesignTwo sample mendelian randomisation study.SettingGenome-wide association study summary data for associations of two single nucleotide polymorphisms associated with plasma caffeine at the genome-wide significance threshold (rs2472297 near theCYP1A2gene and rs4410790 near theAHRgene) and their association with the outcomes.ParticipantsPrimarily individuals of European ancestry participating in cohorts contributing to genome-wide as

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Arciero, Paul J., and Michael J. Ormsbee. "Relationship of blood pressure, behavioral mood state, and physical activity following caffeine ingestion in younger and older women." Applied Physiology, Nutrition, and Metabolism 34, no. 4 (2009): 754–62. http://dx.doi.org/10.1139/h09-068.

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The purpose of this study was to examine the age-related differences in blood pressure, heart rate, and behavioral mood state after caffeine ingestion in younger and older women. Using a placebo-controlled, double-blind design, 10 younger (Y; 18–22 years) and 10 older (O; 50–67 years) healthy women who were moderate consumers of caffeine (self-reported mean intake: Y, 139 ± 152 mg·day–1; O, 204 ± 101 mg·day–1) were investigated. All volunteers were characterized for fasting plasma glucose, insulin, free-fatty acids and caffeine levels, body composition, cardiovascular fitness, physical activit

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