TAILIEUCHUNG - Đề tài: STUDY ON THE EXTRACTION AND ISOLATION OF CAFFEINE FROM GREEN TEA Camellia sinensis (L.)

Caffeine is one of the most popular compounds which are taken everyday by millions of people all around the world. Due to its pleasant flavor and stimulating effect, caffeine is more common than any chemicals and has been consumed for hundreds of years. It is also a key component of many popular drinks and food, such as tea, coffee, soft drinks, energy drinks and chocolate. Recently, caffeine has been used as a drug. It can stimulate the central nervous system and make people more alert, less drowsy and improve coordination. With its unique properties, caffeine has been combined with certain pain relievers or medicines for treating headaches. | After extraction step, caffeine adsorption and desorption with various adsorbent columns were studied. The tea extracts from the optimal extraction condition were passed through different adsorbent columns of XAD-4, XAD-7, IR-120H and activated carbon with a flow rate of 1 ml/min. XAD-4 was found to have the highest adsorption affinity for caffeine and lowest one for EGCG while the contrary results were observed for IR-120H. It was found that the suitable amount of XAD-4 adsorbent for one-time adsorption of caffeine is 7g. Several solvents were used for one-time desorption of caffeine from the adsorbent columns with a flow rate of 1 ml/min and acetone was found to possess the highest strength for caffeine desorption. 125 ml of solvent was found as the suitable volume for one-time desorption of caffeine from the adsorbent columns. EGCG was not found in the desorption solutions from XAD-4, XAD-7 and activated carbon. However, EGCG was found in the desorption solutions by ethanol and acetone from IR-120H column.

• Hoá dầu
• caffeine
• Adsorption
• Apparatus
• IR 120H column
• XAD 4 column
• desorption
• Corrosion inhibition by caffeine and caffeine
• Langmuir adsorption isotherm
• I system for CT38 steel
• 1m hydrochloric acid solution
• Extending the trial periods
• công nghệ sinh học
• kinh nghiệm trồng trọt
• luận văn
• nghiện cứu chiết tách
• công dụng của caffeine
• Chiết Tách Caffeine
• Ebook Caffeine
• Introduction to the Chemistry
• Caffeine Isolation
• and Biosynthesis of Methylxanthines
• Analytical Methods
• Quantitation of Methylxanthines
• Components of Coffee
• Caffeine and chlorogenic acid separation from raw coffee
• Supercritical CO2 in water
• Separation using SCCO
• Water in Batch Modes
• Caffeine in SCCO2 phase
• Effect of temperature on the recovery of caffeine
• Chlorogenic acids
• Caffeine CGAs ratio
• Coffee shop
• Asian country
• Caffeine in various coffee
• Various coffee related products
• Đồ uống có caffeine
• dinh dưỡng trẻ em
• bệnh hay gặp ở trẻ em
• thực phẩm cho trẻ em
• chăm sóc sức khỏe trẻ em
• báo cáo khoa học
• báo cáo hóa học
• công trình nghiên cứu về hóa học
• tài liệu về hóa học
• cách trình bày báo cáo
• Tạp chí khoa học
• Khoa học tự nhiên
• Mix of iodide and caffeine
• CT3 steel
• Corrosion inhibitor
• Vietnam Journal of Chemistry
• The corrosive inhibition ability
• CT3 steel in 1 M HCl solution
• Caffeine and some characteristics
• The inhibition process
• BMC Pharmacology and Toxicology
• Therapeutic drug monitoring
• Pharmacodynamic relationships
• Caffeine citrate therapy
• Heart rate
• BMC Women's Health
• Systematic review
• Meta analysis
• Human infertility
• Caffeine consumption
• Tạp chí Khoa học Nông nghiệp Việt Nam
• Bài viết về nông nghiệp
• Môi trường bảo quản tinh
• Lòng đỏ trứng
• Caffeine trong môi trường TCG
• BMC Developmental Biology
• Cellular slime molds
• Multicellular slug
• Adenosine antagonist
• Caffeine overrides
• BMC Anesthesiology
• Intensive care unit
• Critical care
• Postoperative period
• Caffeine withdrawal
• Facilitate post anaesthetic emergence
• Bột cà phê rang xay
• Hiệu suất thu hồi caffeine
• Dung môi nước nóng
• Quá trình xử lí bột cà phê rang
• Tạp chí Khoa học Đại học Trà Vinh
• human health
• nutrition
• physiological function
• methylxanthine beverages
• Journal of Science and Technology
• Preparation of flower like ZnO architecture
• Photodegradation of caffeine in aqueous solution
• Flower like ZnO architecture
• The degradation efficiency
• BMC Cancer
• Caffeine citrate
• Citric acid
• While multiagent chemotherapy
• Novel chemotherapeutics
• Anti cancer agents
• BMC Pulmonary Medicine
• Hypoxia inducible factors
• Caffeine therapy
• Bronchopulmonary dysplasia
• Premature neonates
• Start your morning off right
• Cut back on caffeine
• Make the most of your commute
• Get 30 minutes of exercise every day
• Get those endorphins going
• Walk every day
• sản phẩm chè xanh
• lá chè tươi ngoại
• phân này bón c cây lạc
• trình bày báo cáo
• tài liệu báo cáo khoa học
• báo cáo nông nghiệp
• báo cáo y học
• công trình nghiên cứu về y học
• tài liệu về y học
• Biopsychological Effects
• Nervous System
• Cognitive Performance
• Mood Disorders
• Caffeine Exposure