| From 24th August of 2001 to 8th April of 2002, Gala (Malus cv.gala) and Golden (M.cv.golden delicious), stored with three different models of cold storage, air condition and ultro-lower oxygen, were kindly provided in different sale time by Inter-profession Technique Center of Fruit and Vegetable of France. The fruits were cut into three parts of the skin, pulp and core according to the human edible habit. The apple polyphenolics in the skin and pulp were determined by thiolysis HPLC and unthiolysis HPLC in Institut National de La Recherche Agronomique, Laboratoire de Recherches Cidricoles. Biotransformation des Fruits & Legumes, Rennes, France. This study will be helpful to guide the businessman to select better storage models and sale time, and also be as a reference for people to consume the apple. All the results are showed as following:1. Thiolysis and unthiolysis HPLC together will be better to quantify the main apple polyphenolics. Thiolysis HPLC will be better for the dihydrochalcones which includes the compounds of xyloglucose phloretin and phloretin, the catechins and their end units. Unthiolysis HPLC will be better for the hydroxycinnamic acids, procyanidin B2 and catechin monomers.2. There were different kinds of apple polyphenolics with different varieties of Gala and Golden. As it is known, the anthocyanidin is only in Gala Skin but not in Golden skin. It is found in this study that there has quercetin in Golden pulp but not be detected in Gala pulp.3. The contents of the different kinds of apple polyphenolics are different. The total content of all the determined flavanols is highest in mg/kg fresh weight, and they are 78-85 percent of the total apple polyphenolics. The hydroxy-cinnamic acids are about 25 percent; the flavonols are 8.2% to 8.5%; the dihydrochalcones are 1.6 to 3.6%; The anthocyanidins are only in red-color skin gala and the percentage of them in the total polyphenolics is 2.2 %.4. The total content of the apple polyphenolics in Gala is 1.94 folds of that in Golden in mg/kg fresh weight. The total content of the apple polyphenolics in Gala skin is 2.20 folds of that in Golden skin and in pulp is 1.21 folds. The proanthocyandins content in Gala is four folds of that of Golden. The other determined apple polyphenolics content is always 1.4 to 2.2 folds of Golden. But the content of phloretin in Golden is higher than that in Gala.5. The total content of all determined polyphenolics in Golden changes less than93that in Gala. Considering the stable of the their content and the costing for storing the apples, Golden apples would be stored in cold storage, air condition and ultro-lower storage for 84 days, 157 days and 182 days, respectively. Gala apples would be stored in cold storage, air condition and ultro-lower storage for 55 days, 107 days and 161 days, respectively.Alkaline phosphatase is an important tool enzyme in molecular biology and ELISA. The human placental alkaline phosphatase (hPLAP) (EC 3.1.3.1) would be used more widely in molecular biology and ELISA for its enzyme activity and heat resistant was higher than that of E.coli alkaline phosphatase (EAP) and calf alkaline phospha- tase (C1AP). It is promising to construct the gene engineering Pichia pastoris to product the hPLAP in a scale for the resource of hPLAP is limited.In this thesis, the hPLAP gene was cloned into the pPICZaA plasmid and induced expressed in the protease-deficient strain P.pastoris SMD1 168. The clone that could secrete hPLAP with enzyme activity was selected. The main results are the following:1 . The hPlAP without signal peptide was expressed in P.partoris SMD1 168 by the pPICZ- a A plasmid.2. The hPLAP induced from the clone with two copies of hPLAP gene had higher enzyme activity. The clone with more or less copy was unfavourable to the hPLAP expression in P.pastoris.3. The cold-heat method without the snailase and zymolyase was used as the PCR direct selecting of colony. To select the colony and suspend with 10 n 1 DDW, and...
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