Search results:
Found 2
Listing 1 - 2 of 2 |
Sort by
|
Sufficient amounts of caffeine were extracted from Kabbos and Wazzah tea leaves, while traces of caffeine were found in green tea leaves which may be due to unriped tea leaves. Extracted caffeine was identified by UV and IR spectroscopy which offered spectra matching precisely the standard caffeine crystals which confirmed the purity of caffeine and the efficiency of extraction methods. Moderate amounts of sodium, potassium and calcium were found in the three types of tea leaves while lithium was found in traces. The results indicated the presence of necessary elements for the metabolic activities of tea plants and humans who take tea drink with their meals.
الخلاصة: تم استخلاص كميات مناسبة من الكافائين من أوراق شاي الكبوس وشاي ألوزه ، بينما تم الحصول فقط على تراكيز ضئيلة من الكافائين فيأوراق الشاي الأخضر والذي قد يعزى إلى عدم نضج أوراق الشاي. وقد تم تشخيص الكافائين المستخلص بأطياف الاشعه فوق البنفسجية والأشعة تحتالحمراء والتي أعطت معلومات تضاهي المعلومات المنتقاة من الكافائين القياسي والتي أثبتت نقاوة الكافائين المستخلص وجدوى طريقة الاستخلاص. وتمالحصول على كميات معتدلة من فلزات الصوديوم والبوتاسيوم والكالسيوم في أوراق الشاي بأنواعه الثلاثة بينما كان الليثيوم بتراكيز ضئيلة. بينت هذهالنتائج وجود أو توفر بعض العناصر الفلزية الضرورية للفعاليات الحيوية لنبات الشاي وللناس الذين يتناولون شراب الشاي مع وجباتهم الغذائية
Caffeine --- Extraction --- Calibration Curve --- Separating funnel --- Methylene Chloride --- Dichloromethane
Cloud point extraction (CPE) method was successfully used for estimation and preconcentration of Allura red by spectrophotometry. The procedure was depended on the extraction of Allura red as an ion pair with cetylpyridinium chloride from aqueous solution using a nonionic surfactant TX-114 or Brij-35. The absorbance of the extracted surfactant-rich phase was measured at 507 nm after dilution with water. The influence of different factors on cloud point extraction (CPE) of Allura red such as pH media, equilibrium temperature, incubation time, concentration of surfactant and electrolyte concentration were investigated. Calibration curve was linear in a concentration range between 2-40 μgml-1 of Allura red with correlation coefficient r= 0.9998 for TX-114 and 0.9992 for Brij-35.The developed procedure was applied for estimation and preconcentration of Allura red in different food samples.
Cloud point extraction --- CPE method was successfully used for estimation and preconcentration of Allura red by spectrophotometry. The procedure was depended on the extraction of Allura red as an ion pair with cetylpyridinium chloride from aqueous solution using a nonionic surfactant TX-114 or Brij-35. The absorbance of the extracted surfactant-rich phase was measured at 507 nm after dilution with water. The influence of different factors on cloud point extraction --- CPE of Allura red such as pH media --- equilibrium temperature --- incubation time --- concentration of surfactant and electrolyte concentration were investigated. Calibration curve was linear in a concentration range between 2-40 μgml-1 of Allura red with correlation coefficient r= 0.9998 for TX-114 and 0.9992 for Brij-35.The developed procedure was applied for estimation and preconcentration of Allura red in different food samples.
Listing 1 - 2 of 2 |
Sort by
|