| In this study, Narcissus tazetta var. chinensis was used as the main material. Different methods were adopted to analyse the composition and variations of volatile constituents in flowers, leaves and tissue-cultured plantlets and the chemical components of essential oil from dried flower and dried leaf. The impact of Gibberellic acid on the synthesis of linalool was studied, as well asβ-glucosidase and alcohol acyltransferase in essential oil. Connection among the changes of cotents of free amino acids, free fatty acids and soluble sugar and essential oil has been researched. Free and bound volatile components in Narcissus tazetta var. chinensis have also been isolated and compared. The effects of volatile constituents on human health have also been involved. Because alcohol acyltransferase and linalool synthase are related to synthesis of esters and linalool, auther attempted to clone genes involved in these enzymes. The main results are as follow:1. Volatile constituents have been extracted by 65μm PDMS/DVB fibre,50/30μm DVB/CAR/PDMS fibre,75μm CAR/PDMS fibre, 100μm CAR/PDMS fibre under the same conditions. Volatile constituents extracted by each fibre are different, however, E-ocimene, Z-ocimene, linalool, benzyl acetate and phenyl acetate have been mostly absorded.2. The main volatile constituents are ocimene, linalool, benzyl acetate, phenyl acetate at different temperatures, daily change and conditions, though the measured components are some differences in the type and content. Different varities "yulinlong" and "jinzhanyintai" have samilar volatile constituents.3. The main volatile constituents in leaves of Narcissus tazetta var. chinensis are 3Z-hexen-1-ol, acetate,E-ocimene, benzyl acetate, Z-butyricacid-3-hexene esters, phenyl propyl.4. The essential oil in dried flowers is palmitic acid and linoleic acid, while in dried leaves is palmitic acid, phytol, myristic acid and phenylacetaldehyde.5. To study GA how to affect the synthesis of linalool, we added 30mg/L,50mg/L,70mg /L concentration of GA into the tissue culture medium. The results showed that linalool was not detected from the seedling growing in GA medium and control medium.6. During flowering, it is positive correlation between changes of phenylalanine content and major esters of volatile components. From early opening to full opening, oleic acid may be used in the synthesis of volatile substances; linoleic acid decline from the flower bud to early flowering, and at this stage, the degradation reaction may produce a series of volatile substances. Glucose gradually rose to peak from the flower bud, first opening to full blooming, and then declined. Endogenousβ-glucosidase activity increased gradually from the bud stage to full bloom, catalytic glycosidic bonds hydrolysis fracture, releasing glucose, leading glucose levels increased and flavor compounds also gradually increased.7. The activities of endogenousβ-glucosidase enzyme and alcohol acyl transferase had some correlation with the content of esters and linalool. Exogenousβ-glucosidase could release volatile substances such as linalool and so on, which could combine with glycosidic bonds by hydrolyzing it.8. The free state and bonding state of volatile components of powder from full-bloom stage were separated through Amberlite XAD-2 resin column. We found that volatile components in free state were more than those in bonding state. Glucose was found when enzymatic hydrolyzing the bonding state of volatile components and the content of fructose was also higher, which showed thatβ-glucosidase could hydrolyze glycosidic bond to monosaccharide and release volatile substances that could combine with glycosidic bond. However, linalool was not found when the bonding state was enzymatic hydrolyzed and there were not the same and significantly increased components when comparing with the free state.9. The effects of aroma constituents on human blood pressure, heart rate and respiratory rate have been tested in a laboratory with a certain amount Narcissus tazetta var. chinensis. Youth group has the greatest drop in blood pressure after smelled an hour, while middle-aged group has the greatest drop after two hours. This may be due to better lung function of young people. They took a deeper breath when the force smells, the aroma compounds to stimulate the body to produce the corresponding biologically active substance, making slow heart rate, blood pressure, reduce the myocardial oxygen consumption. As poor pulmonary function, the middle aged and old people mainly by increasing the time smelling breath rate, resulting in an increase in heart rate, but the difference was not significant. Narcissus tazetta var. chinensis can reduce normal blood pressure in people with borderline hypertension, heart rate and respiratory rate of performance for the double entry regulation.10. Alcohol acyl transferase and linalool synthase are the key enzymes that are related to synthesis of esters and linalool. Alcohol acyl transferase gene (AAT) and linalool synthase gene (LIS) were cloned. The length of clone fragment of AAT obtained was close to those AAT cDNA reported in the literature, but sequence analysis showed that it didn't exhibit similarity with those genes in GenBank. It can't be confirmed whether the cloned fragment is the AAT cDNA fragments. After sequence analysis, result showed that the clone fragment of LIS exhibited very low similarity with those genes in GenBank, but it presented two typical conserved motifs of terpene synthase,i.e RR and DDXXD. It would be confirmed whether the clone fragment of LIS belong to LIS family after full length clone and functional analysis.
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