从8种载体材料中选取自制的氨基含量约2.878mmol/g的甲壳质作为固定化载体，采用吸附交联法，以戊二醛为交联剂，对木瓜蛋白酶进行固定化。17.5mg/g的固定化酶载体比例，pH6.5，5℃下，先吸附10min，再以0.7%的戊二醛终浓度交联12h，所得固定化酶酶活回收可达52.0%，酶活力为3.54U/g。固定化酶在65℃以下，溶液酶在55℃以下稳定；固定化酶在pH7.0以下稳定，溶液酶在pH6.0以下稳定；5℃条件下，固定化酶贮藏半衰期为183d；以酪蛋白为底物，固定化酶的操作半衰期可达27d。用固定化酶水解甲壳胺，产物分子量小于10000的甲壳胺低聚糖得率约45.55%。

The phospholipids of mussels (Mytilus edulisl Linne) from the coast of Qingdao were extracted, fractionated and analysed over a 12 month period. Thecontents of total lipids, neutral lipids, polar lipids and phospholipids were meausred. The composition of phosholipids was determined by high-performance liquid chromatiorgraphy, and their fatty acid composition was analysed by gas chromatorgraphy. Thephospholipide contert ranged from 3.6 to 6.4 g kg-1 soft tissue. Pe (phosphatidyl ethanlaminc) and PC (phosphatidyl chline) were the major constituents. C16:0, C20:5 and C22:6 wree the major fatty acids. C20:5 (5.25-23.10%) and C22:6 (6.05-20.42%) varied regularyly with the seasonal factors, Their total amounts were high from January to Juhne, which wouldbe an optimal time for the utilisation of trhe phospholipids of mussels.

Muscle residue depletion of chloramphenicol (CAP), sulphamethoxazole (SMZ) and oxytetracycline (OTC) following oral administration was evaluated in shrimp, Penaeus chinensis under field conditions. Three groups of shrimps were cultured in tanks filled with seawater and fed a commercial medicated diet containing 2000 mg kg 1 CAP, SMZ and OTC, respectively, twice daily for 3 days. Sampling was conducted at different intervals (0, 0.5, 1, 1.5, 2, 3, 4, 8, 10, 12, 16, 24, 36, 48, 72, 96, 120, 144, 168 h) after the cessation of medication. Drug analysis was carried out by HPLC. The elimination half-life (t1/2) of CAP was 10.04 h, the elimination half-life (t1/2) of SMZ was 5.68 h and that of OTC was 16.12 h. If the EU MRPL value of 0.3 ng/g for CAP and MRL value of 0.1 Ag/g for SMZ and OTC quoted for muscle from finfish is extended to shrimp muscle, extrapolation of the data indicates that it would be passed after a 139.7 h (95% CI=132.0-144.4 h), 30.6 h (95% CI=27.2-33.1h), 90.3 h (95% CI=87.9-92.5h) withdrawal period for CAP, SMZ and OTC in shrimp muscle, respectively.

Immobilized papain was used to prepare chitosan oligomers and the optimum conditions were as follows: NaAc-HAc buffer system, pH 4.0, temperature 45℃. After 24 h reaction with stirring, nanofiltration and ultrafiltration were used to desalt and isolate chitosan oligomers into different molecular weight fractions respectively. The yield of chitosan oligomers with molecular weight under 10,000 was 49.55% to total substrate, while that of between 600 and 2000 was 11.07%. The fractions 01, 02 was analyzed by Sephadex G-50M gel filtration chromatography and flight mass spectrograph was employed to analyze the fraction O3. The results showed immobilized papain could depolymerize chitosan successfully, and separating the product by ultrafiltration membrane was feasible. Further study revealed that the immobilized papain could be repeatedly used at least 10 times. An amount of 1 mg free papain and mmobilized papain could produce 2.57 and 17.34 mg chitosan oligomers, respectively. The results indicated that the depolymerization efficiency of immobilized papain was obviously higher than that of free papain.

A low molecular weight sulfated polysaccharide (L-A) was prepared by mild acid hydrolysis of crude fucoidan (F-A) from Laminaria japonica. In comparison with F-A, L-A had a lower proportion of fucose residues, but a similar proportion of sulfate. The galactose content of both fractions was relatively high, especially for L-A (57%). The antioxidant properties of the two polysaccharides were studied using two low-density lipoprotein oxidation systems. L-A had a stronger effect against low-density lipoprotein oxidation in both systems. F-A inhibited the AAPH-induced low-density lipoprotein oxidation, but had little effect on the CuCC-induced system due to its large molecular mass. The active sulfated fraction L-A, containing alactose, mannose and fucose (about 9: 2: 2) is reported here for the first time.