Study On The Active Ingredients And Years Identification Of Exocarpium Citrus Grandis

Exocarpium Citri Grandis (ECG) is the dried ripe peel of Citrus grandis Osbeck and its cultivars, which has been acknowledged by the People’s Republic of China pharmacopoeia, and has been used in traditional Chinese herbal medicines for a long time. ECG is mainly produced in Huazhou county of Guangdong Province in China, and it is regarded as geoherbs. It has been applied in foods and drugs due to the effectiveness of regulating qi (energy), normalizing the function of spleen and stomach, resolving phlegm, and so on. This study was established in the systemic discussion of the active ingredients in ECG. The difference in composition and content of the active ingredients, physical and chemical properties of ECG were analyzed. An sensory evaluation was conducted by the means of Fuzzy Mathematics. Besides, electronic tongue and electronic nose were used to recognise the difference in the ECG with different years.The major results of the study are as follows:1. Comparision of major functional components in ECG with different storageThe content of total flavonoids in ECG with diferent years was quite different with each other. Overall, the storage time was longer, the content of total flavonoids was higher. Despite the passage of time, the narigin content was stable. The ECG polysaccharide was composed of D-xylose, D-glucose, D-semi-lactose, D-arabinose, D-mannose sugar and unknown ingredients, among which D-semi-lactose was the most. With the duration of storage time, the content of ECG polysaccharide decreased after increasing. The coumarin extracted from ECG with different storage time was mainly composed of Coumarin and Isoimperatorin, and the content as well as composition of the coumarin was different. The volatile components decreased with the duration of storage time. During this process, the content of D-limonene decreased, a-pinene and β-pinene increased, and y-teipinene as well as terpinolene decreased after increasing. The GC-MS analysis revealed that the main component of volatile oil in ECG of different storage time was basically the same. The content of (+)-limonene was the highest. With the increase of storage time, the volatile components of ECG reduced, and the content of (+)-limonene also decreased.2. Sensory evaluation on ECG of different storage years based on fuzzy mathematicsDuring the process of study on the physical and chemical properties of ECG, we found that their transmittance showed an upward trend as the scan wavelength changed from400to800nanometer, and some samples were overlapping. As a result, it was hard to distinguish the ECG of different storage years by means of UV scan or observation. Other means were necessory. The density of ECG solution with different storage years changed little that they were about1.000mg/mL. While the color values such as L*values and b*values changed a lot, a*values changed little. This suggested that the brightness and yellowness of ECG changed a lot, the red remained stable. In the ECG solution, mineral elements such as Zn, Fe, Mg, Al and Ca were rich, while As, Cr, V, Be, Sb and Ti were not detected. In the sensory evaluation, samples of2002and2008were evaluated as the best,2001,2003,2004,2009and2010the second, the rest were little poor.3. Years recognition study of ECG based on ET and EN technologyThe discriminant index of principal component analysis on ECG was83, and that of discriminant factor analysis reached99.622%. This suggest that the analysis by electronic tongue remained most information to distinguish the samples effectively. The electronic tongue could also effectively distinguish between ECG and other samples such as orange, lemon, sweet orange, pomelo, and smelly tangerines. The electronic nose was also able to do this, but it operated poorly when identified ECG of different storage time. This suggest that it was hard for the electronic nose to finish the test.4. The analysis on aroma components of ECG with different storage timeThough the aeoma composition of ECG with different storage years was similar, there were still some differences in the composition and content. This study found that the characteristic aroma components of ECG were terpenes, including monoterpenes and sesquiterpenes vinyl. In addition, oxygenated terpenes, such as terpenols, terpene aldehydes and terpene esters, were also the main aroma components. In the ECG samples, limonene was of the highest content in monopenes. The longer the storage time was, the lower the content of limonene became.