difference in the mean change in pulse rate (P>0.05) between those participants ingesting caffeine in comparison to those that did not consume caffeine and therefore the null hypothesis‚ HO‚ was accepted (Refer to appendix 2 for hypotheses). Similarly‚ there is no significant difference between the mean change in respiration rate (P>0.05) of subjects that consumed caffeine and subjects that did not consume caffeine. Therefore the null hypothesis‚ HO‚ was accepted. (Refer to appendix 2 for hypotheses)
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Extraction of Caffeine from Tea Leaves Santos‚ Raphael‚ Samson‚ Nonia Carla‚ *Tabora‚ Brylle‚ Tan‚ Kate Michal Department of Biological Sciences‚ University of Santo Tomas‚ Manila‚ Philippines Abstract Tea leaves are natural products that are harvested from agriculture. Caffeine‚ on the other hand‚ is a stimulant that has been shown to speed up the time of reaction‚ increase alertness‚ and improve one’s concentration. What we did in this experiment was to extract the alkaloid caffeine content
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Extraction of Caffeine from Tealeaves Perez‚ Albert Solomon K.*; Quiambao‚ Marie Angela C;.Pascua‚ Hanna Harriette R.; Patricio‚ Maria Roxanne DC.; 2-Chemistry‚ Department of Chemistry‚ College of Science University of Santo Tomas España St.‚ 1015‚ Manila Abstract Caffeine is soluble in both water and organic solvents‚ solid-liquid extraction and liquid-liquid extraction were used in the experimentation process. Caffeine was extracted using hot water‚ however‚ due to its
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Extraction of Caffeine from Lipton Yellow Label Teal Leaves Arlie Bamiano‚ Jealine Bernabe‚ Petrenne Caimbon*‚ Jhia Caso Department of Biology‚ University of Santo Tomas Abstract In order to extract pure caffeine from Lipton Yellow Label tea leaves‚ several extractions and phase transition techniques were employed to 6.5029 grams of sample. Initially‚ the tea leaves were boiled in water to extract tea from the leaves (Solid-Liquid Extraction). After extracting the tea‚ several steps of
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Extraction Report For experience 4c we were supposed to determine which one is the organic layer in three different tubes that has two layers. To determine which is aqueous (water) or organic‚ I used the technique of adding droplets of water to each tube. If the layer is water‚ then the drops of added water will dissolve in the aqueous layer and increase it’s volume. If the added water form droplets or a new layer‚ then it is the organic layer. Tube 1 (water and n-butyl chloride)‚ after adding
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describes the extraction of caffeine from tea leaves to determine its % caffeine. The extraction process selectively dissolves one or more compounds in a mixture into an appropriate solvent. In this experiment‚ it was visible in the process wherein the components of the tea leaves were dissolved in two solvents‚ water and dichloromethane (DCM)‚ with DCM used for multiple extractions. The organic layer was evaporated and the determined % caffeine was 0.12%. Furthermore‚ the purified caffeine was subjected
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Extraction of Caffeine from Thea sinensis Abstract Extraction of Caffeine from Thea sinensis main objective is to isolate‚ purify characterized caffeine from tea leaves. Sublimation technique was used to get the % yield which is 0.07%. The melting point of the standard caffeine with the sublimate is 229°C. Introduction The active ingredient that makes tea and coffee valuable to humans is caffeine. Caffeine is an alkaloid; a class of naturally occurring compounds containing nitrogen and
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Extraction of Caffeine from Tea Leaves Introduction Caffeine is soluble in boiling water and as a result it is easily extracted from tea bags by steeping in hot water. This process leaves behind the water insoluble portions of the tea bag. However‚ water extracts more than just caffeine‚ so a final separation is done with an organic solvent that will dissolve primarily caffeine. The organic solvent used in this experiment is Dichloromethane (CH₂Cl₂). Dichloromethane is less polar than water
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Extraction of Caffeine from Tea Leaves Department of Biological Sciences‚ College of Science University of Santo Tomas España‚ Manila‚ 1028 ABSTRACT: Caffeine is a white crystalline xanthine alkaloid that acts as a stimulant drug. Caffeine is found in varying quantities in the seeds‚ leaves‚ and fruit of some plants. It is most commonly consumed by humans in infusions extracted from the seed of the coffee plant and the leaves of the tea bush‚ as well as from various foods and drinks containing
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Preparation of SKEO The extraction of S. khuzistanica was performed by hydro distillation and clevenger apparatus for 5 hours. Once extraction was completed‚ the resulted essential oil was dehydrated using sodium sulfate (Merck). The essential oil was stored at temperature of 4ºC until using (12). In order to provide different concentrations of the extract‚ Dimethyl sulfoxide (DMSO) was used. Gas chromatography/mass spectrometry analysis of essential oil Isolation and measurement of the sample
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