Drink a Cup of Coffee and Brighten the Day Sheng Guo UCSD Chem 151 Pro. Whitesell 3/9/2014 Millions of people around the world wake up every day and are still day dreaming. The first thing they would do is to make a cup of coffee where this This small volume of liquid can change human s behavior dramatically, and boost the efficiency on the daily tasks. The secret within the coffee is the molecule called caffeine. Millions of people around the world depend on the effect of caffeine to either boost or obtain the ability to do daily tasks. After drinking coffee, the effects of caffeine usually start within one hour and gradually fades around five hours. There are some signs of potential benefits of drinking coffee such as reduce the chance of heart attack, but more research has to be done to confirm this. The first use of caffee can be traced back to 1300s, and it was intruduced to America around 1700s while around 18,000 caffee trees were planted due to the popularity. In a recent study, more than 90% of adults in North America drink coffee on the daily basis. According to the Food and Drug Administration, coffein is considered to be a safe drug. Since the toxic dose is over 10g per day for an average adult human, and people usually have less than 500mg per day. For the pregant women, caffeine consumption should not be over 200mg per day. Overall, the number associated with toxic dose depends on the tolerance of caffein of the individuals. In 1891, caffeine was isolated by a German chemist called Friedlieb Ferdinand Runge for the first time. Caffeine belongs to the alkaloid group has a chemical formula of C8H10N4O2, molecules in this group usually contain a basic Nitrogen atom. It has a bitter taste and the pure compound has a white color. It is used as a stimulate drug. The major source for caffeine is from the coffee beans. The longer the roasting time, the less the caffeine content in the coffee due to the heating process. Caffeine is also used in soft
drinks. Red Bull is an energy drink that claims to enhance the brain and physical performance contains 80mg of caffeine per serving. Biological Relations After the intake of caffeine either from coffee, tablets or other sources the small intestine will absorb the caffeine within 45 minutes after ingestion and transfer to the rest of the body tissue. The concentration of the caffeine will reach its peak around the first hour, which depends on the degree of tolerance of caffeine as individuals may have different metabolism rates to get rid of the caffeine molecules. Roughly, the time for an adult to eliminate the caffeine molecules is 5 6 hours. Generally, the effect of the caffeine helps to boost people s working efficiency by eliminating fatigue and the addition of another cup of coffee will help the brain to stay alert for another 5 or 6 hours. The structure of caffeine resembles adenosine and camp (explain what this is). This closeness in structure gives Caffeine the ability to bind to the receptor sites intended for adenosine and camp. When adenosine binds to its receptor, humans feel some degree of drowsiness. When the night approaches or when waking up without enough of sleep, the concentration of adenosine is high thus allowing more of it to bind to the receptors. As a result, humans feel drowsiness and the working efficiency is limited. Caffeine has a structure resemblance as adenosine could bind to the receptors for adenosine, this would limited the amount of adenosine molecules of binding to the receptors and sending signal of tiredness to the brain. camp has the ability to increases blood pressure and deliver oxygen to the human brain. camp-pde breaks down camp to a non-cyclic monophosphate causing the camp to lose it functionality. Caffeine s structure resembles camp and adenosine, which allows it to bind to its receptor. The receptor is camp-pde and the binding can delay the breakdown of camp. As the result more oxygen would be delivered to the brain and prolong the excitation of brain activity. Caffeine is a very effective molecule that is able to block the binding of adenosine and camp to delay the drowsiness and prolong the brain excitation.
After the consumption of caffeine, people who are less dependent, will find an increase in awareness and prolong in the brain excitation state. People who have formed dependency on caffeine will consume a product that contains caffeine only to obtain their regular ability. Some people have forced some degree of tolerance to caffeine and the addiction would have a serious drawbacks once they stop consuming caffeine. It is fortunate that the withdrawal effect would only happen for a few weeks depending on the degree of dependency of people on caffeine and the effects will slowly fade away. But during the first few weeks, the withdraw symptoms could be dreadful for those who consume caffeine heavily on the daily basis. The disadvantage of coffee is the withdrawal effects when people suddenly stop the intake caffeine. Based on the dependency on the molecule caffeine, people would suffer from mild symptoms like sleepiness to severe conditions like headache or even depression. This withdrawing symptom are caused by sudden decrease the intake of caffeine that would normally bind to the receptors for adenosine and camp. Normal amounts of adenosine and camp binds to their receptors, but compared to the amount that usually binds to the receptor and sends signal to the brain when there is the interference of caffeine. The brain will have a hard time to process increases in the signals sent by adenosine and camp and the result is the withdraw symptoms. People who drink more than 5 cups of coffee would have greater withdraw symptom than the people who drank less than 2 cups per day. People who drank more cups of coffee would have less adenosine and camp bind to their receptors thus less signals will be sent by these molecules to the brain. With the absence of caffeine, the sudden increase of the amount of signals would be greater than those who drank less coffee and they would suffer from more severe withdraw symptoms. With an overdose caffeine of over 500mg, the body will display some serious symptoms such as a headache, muscle twitching, breathless, over excitement and restlessness. Overdose of caffeine can also result in death in some extreme cases. Studies have found that over 80 cups of coffee per day for the adult can result in death. The specific number of cups depends on the caffeine tolerance of the individuals. Drinking over 80 cups of coffee in a single day may be hard to achieve, but there are other ways that people can overdoes caffeine, that is by taking caffeine tablets. Abstract caffeine from Plants Some people have a very tight schedule, they do not have the time to enjoy a cup of coffee but instead just take caffeine tablets for their effects of increase awareness and boost working efficiency. For the regular caffeine tablets there is 100mg of caffeine per serving, and for the extra strength caffeine tablets the caffeine per serving increased to 200mg. A person may be overdose and display serious symptoms if one takes over 40 tablets per day. Not all people drink coffee for the effect on caffeine on their body. Some people simply enjoy the taste of the coffee and with different blend, coffee can be a really
tasty drink. People who love the taste of the coffee but don t want any effect of the caffeine and choose to buy the decaffeinated coffee. The caffeine molecules in coffee were extracted through a chemistry reaction and the final product doesn t contain caffeine but the taste of the drink stayed the same. Ingestion of the decaffeinated coffee will not yield any effects that produced from caffeine like increase alertness and the excitation state of the brain. The decaffeinated coffee is suitable to people who want to drink a cup before going to sleep but don t want that extra effect from the caffeine. Tea leaves also contain some levels of caffeine depends on the type of the tea. The following procedures are for extraction of caffeine from the tea leaves. 1. Boiling tea in water and CaCO3 2. Extract organic layer after combined with 3ml methylene chloride 3. Extract the organic layer after combine with saturated NaCl 4. Evaporate the methylene Chloride in the organic solution extracted 5. Purify the solution by sublimation. (Relative pure caffeine can be obtained) Some people compare coffee with smoking and drinking due to the similiarity of dependency. But from the research by the Harvard School of Public Health, they followed 130,000 people over the course of average 20 years. The result was that there is no significant evidence that shows the people who died during this period were related to drinking coffee in any way. In other words, intake caffeine for it benefits of increase awareness and boost efficiency in work have no relation to any death relation in this research. There are some research that claim the caffeine has potential benefits to the human body such as protection against type 2 diabetes, Parkinson s disease, liver cancer, and liver cirrhosis. But more research have to be done to confirm this, since caffeine doesn t work like other intensive drugs like opium that have relative short reaction time with the human body. In order to study the effects of caffeine to human body it takes years even decades of research. But only a few percentage of people out live to the 100 mark, so let s have a cup of coffee and brighten rest of the day.
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