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1.
以菠萝(Ananas comosus Merr)为原料，应用改良的方法对菠萝天然酶活力进行测定，对菠萝酶活力变化进行了初步探讨。结果表明：测定未成熟、成熟菠萝酶活力分别为106．10和65．85u／mL；菠萝肉、皮、整果汁酶活力分别为86．98、50．72、55．21u／mL；室温贮藏，酶活力取样时为54．97u／mL，第4天达最高值72．78u／mL，第8天降至43．66u／mL；4℃贮藏，酶活力取样时为54．97u／mL，第2天达最高值71．68u／mL，第4天降至50．12u／mL，即不同温度下贮藏不同时间酶活力变化是先升高后降低。 相似文献
2.
以菠萝 (AnanascomosusMerr)为原料 ,应用改良的方法对菠萝天然酶活力进行测定 ,对菠萝酶活力变化进行了初步探讨。结果表明 :测定未成熟、成熟菠萝酶活力分别为 10 6 .10和 6 5 .85u/mL ;菠萝肉、皮、整果汁酶活力分别为 86 .98、5 0 .72、5 5 .2 1u/mL ;室温贮藏 ,酶活力取样时为 5 4.97u/mL ,第 4天达最高值 72 .78u/mL ,第 8天降至 4 3.6 6u/mL ;4℃贮藏 ,酶活力取样时为 5 4.97u/mL ,第 2天达最高值71.6 8u/mL ,第 4天降至 5 0 .12u/mL ,即不同温度下贮藏不同时间酶活力变化是先升高后降低 相似文献
3.
对青鳞鱼肌肉蛋白质风味酶的水解条件及产物进行了详细研究.正交试验结果表明,在2 h内,风味酶对肌肉蛋白质的最适宜条件为酶浓度180×103IU/g、45 ℃、pH7.0 及底物浓度3.3%;产物分析提示风味酶对胱氨酸、缬氨酸、蛋氨酸、亮氨酸、苯丙氨酸、组氨酸及酪氨酸结合的肽键具有最高的特异性,它还具有形成新的肽键的能力;在10～180 min内任一时刻的水解产物经过离心,0.45 μm-和0.22 μm过滤而得到的水解物的分子大小没有明显的差异,同时10～180 min内任一时刻的离心水解产物间的平均相对分子质量也没有明显差异.研究结果为青鳞鱼的综合利用提供了基础理论依据. 相似文献
4.
There are many reports that cells (protoplasts) separated from the thallus of Porphyra by enzyme can develop to normal leafy thalli in the same way as monopores. But there are few investigations on the subcellular structure of the isolated vegetative cell for ccmparison with the subcellular structure of monospores. To clarify whether the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores undergo in their formation and germination, we observed their ultrastructure, ccxnpared them with those of the monospore and found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore formarion, such as production of small and large fibrous vesicles, but was acccxnpanied by vacuolation andstarch mobilization like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells. 相似文献
5.
The total content ot the nch amino acids in two common red algae, Potystpnoma urceolata and Polysiphonia japonica growing in the Qingdao seashore were determined. The algae powder was hydrolyzed by 6 mol/L HC1 at 110℃ for 48 h and determined by amino acid analyzer. The content was 25.35% and 24.16% , respectively, much higher than that of some other species. In addition, a nutritive liquid with abundant amino acids was prepared (by the enzymatic hydrolysis method using Polysiphonia urceolata ) as raw material for a kind of health beverage. The dried seaweed was decolored by 0.25% KMnO4 and 0.5% active carbon, then enzymalized. In the selection of enzymalizing condition, the orthogonal experimental design was used. Four factors including kinds of enzyme, quantity of enzyme, temperature and time were studied at 3 levels. According to the orthogonal design results, we can choose an optimal condition: hydrolyzing at 45℃ by neutral proteinase (0.25% , w/w) for 2 h, adjusting pH to 8.5, then adding trypsin (0.25% , w/w) and hydrolyzing for 2 h. Finally the above solution was alkalized by NaOH and neutralized by casein. After the hydrolyzed liquid was filtered and concentrated, suitable additives were added. The final products contain rich amino acids. 相似文献
6.
应用"酶”分析法对几种粗饲料和不同精、粗饲料比的3种日粮的化学成分进行了分析,并利用低消化性纤维(Ob)含量不同的日粮进行了饲养和消化试验.结果表明细胞内容物有机物部分(OCC)含量花生藤最高,稻杆含量最低;细胞壁物质有机物部分(OCW)中的Ob含量以稻杆最高,花生藤含量最低;日粮中精料比例每提高10%,Ob含量减少约2.3%;山羊的日增重以精、粗饲料比23,Ob含量37.75%的效果最好,日粮中Ob含量过多或过少,都将影响山羊的日增重;OCW中的高消化性纤维(Oa)的消化率为63.38%,Ob的消化率为19.21%. 相似文献
7.
甘蔗品种过氧化物酶同工酶稳定性分析 总被引：1，自引：0，他引：1
以不同甘蔗品种为材料,用垂直平板聚丙烯酰胺凝胶电泳,进行同一品种在不同种植地区及同一植株不同叶位的同工酶酶谱比较。结果表明,不同品种其酶谱在酶带强度、带数及Rf上有明显的区别,但同一品种在不同种植地区、不同植株、同一植株不同叶位其酶诺无明显差异,体现了同工酶作为品种标记的稳定性。 相似文献
8.
胰蛋白酶的固定化采用吸附-交联法.在单因素试验基础上,通过正交试验,获得了胰蛋白酶固定化的最佳条件酶与载体体积比为21,吸附时间为10 h,pH=4.5,缓冲液浓度为0.05 mol/L,戊二醛的质量分数为0.1%.此条件下制得的磁性酶活力回收在50%左右,相对酶活力达74%,该磁性酶对啤酒澄清防止冷浑浊有明显效果. 相似文献
9.
应用“酶”分析法对几种粗饲料和不同精，粗饲料比的3种日粮的化学万分进行了分析，并利用低消化性纤维（Ob)含量不同的日粮进行了饲养和消化试验，结果表明，细胞内容物有机物部分（OCC）含量花生藤最高，稻杆含量最低；细胞壁物质有机物部分（OCW）中的Ob含量以稻杆最高，花生藤含量最低；日粮中精料比例每提高10%，Ob含量减少约2.3%；山羊的日增重以精，粗饲料比2：3，Ob含量37.75%的效果最好，日粮中Ob含量过多或过少，都将影响山羊的日增重，OCW中的高消化性纤维（Oa)的消化率为63.38%，Ob的消化率为19.21%。 相似文献
10.
Information regarding antioxidant enzymes in amphioxus remains lacking, and this study was carried out to examine the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in different genders and tissues of amphioxus Branchiostoma belcheri tsingtauense. Results show that (1) CuZn-SOD, CAT and GPX activities in the whole amphioxus B. belcheri tsing- tauense were basically at the same levels in male and female amphioxus, whereas both T-SOD and Mn-SOD activities in male amphioxus were significantly higher than that in the female (P<0.05); (2) The testis had significantly higher T-SOD and CuZn-SOD activities than the ovary (P<0.05); (3) CuZn-SOD activity was undetectable in the guts of male and female amphioxus; (4) For both male and female am- phioxus, the activities of CAT and GPX in the gonads including testis and ovary were the lowest (P<0.05) among the tissues examined; (5) The gut and gill had the same level GPX activities while the gut had a higher CAT activity; (6) There was no clear difference in CAT and GPX activities in the corresponding tissues between male and female amphioxus. The study on SOD, CAT and GPX activities in different genders and tissues of the protochordate provides data for future comparison of amphioxus antioxidant enzymes with those of invertebrates and vertebrates. 相似文献
11.
以不同甘蔗品种为材料,用垂直平板聚丙烯酰胺凝胶电泳,进行同一品种在不同种植地区及同一植株不同叶位的同工酶酶谱比较。结果表明,不同品种其酶谱在酶带强度,带数及Ｒｆ上有明显的区别,但同一品种在不同种植地区,不同植株,同一植株不同叶位其酶谱无明显差异,体现了同工酶作为品种标记的稳定性。 相似文献
12.
Screening of 46 putative enzyme-coding loci and 4 different kinds of tissues of Sepiella maindroni de Rochebrone, 1884 for enzymatic activities using starch gel electrophoretic technique proved that the 21 enzymes such as AAT, AK, ALP, AP, CK, DIA, ES, FBP, G3PDH, GPI, GRS,IDH, LDH, MDH, MEP, MPI, NP, PGDH, PGM, SOD and XO* , were active to Sepiella maindroni after being stained. The tissue exhibiting stable and clear bands was also determined. Among tissues tested, mantle muscle tissue was the best for electrophoretic survey of isozymes. Buccal bulb muscle, eye and liver were fairly good for some special enzymes, such as DIA, ES, MPI, NT, etc. 相似文献
13.
FU Xiaoting LIN Hong KIM Sang Moo 《中国海洋大学学报(英文版)》2008,7(1):97-102
Carbohydrases secreted by marine Vibrio sp. YKW-34 with strong Laminaria cell wall degrading ability were screened, and among them alginate lyase was found to be dominant. The effects of medium composition and culturing condition on the production of alginate lyase by marine Vibrio sp. YKW-34 in flask were investigated in this study. In the culture medium of marine broth, no alginate lyase was produced. The activity of the alginate lyase, after being induced, reached 5 UmL^-1. The best inoculum volume and inoculum age were 10% and 12h, respectively. The optimal temperature for alginate lyase production was 25℃. The fermentation medium was composed of 0.5% of Laminaria powder and 0.2% of KNO3 with an initial acidity of pH 8.0. Alginate could induce alginate lyase production but not as efficiently as Laminaria powder did. The addition of fucoidan, cellulose and glucose had negative effect on the alginate lyase production. Other kinds of nitrogen sources, such as yeast extract, beef extract and peptone, had positive effect on the growth of the microorganism and negative effect on alginate lyase production. In addition, the time course of alginate lyase production under the optimized condition was described. The optimal harvest time was 48 h. 相似文献
14.
GSH system plays a role in the control of the redox balance state,anti-oxidation and protecting life from injury of ROS(reactive oxygen species).In present paper,the possible GSH system of Chlamydomonas sp.ICE-L has been investigated by evaluating GSH and GSH-related enzymatic responses at different temperatures using spectrophotometer methods.The results showed that the GSH system is correlated positively to low temperature,and other factors but GR are correlated negatively to high temperature.So GSH and GSH-related enzymes play an important role in the adaptation of Antarctic ice microalgae to low temperature. 相似文献
15.
甲壳素(chitin)广泛存在于虾、蟹等甲壳动物,部分植物,细菌及真菌等生物中,是仅次于纤维素的第二大类天然高分子化合物,年平均产量达数十亿吨之多[1]。壳聚糖(chtiosan)是甲壳素脱乙酰化产物,是膳食纤维中唯一的一种含有阳离子的高分子基团[2]。甲壳素及壳聚糖具有很多优越的特性,但由于溶解性较差,影响了它在各行业中的应用。为了改善壳聚糖的溶解性以及一些医学、保健性质,对其各种衍生物及壳聚糖低聚物的研究已逐渐展开[3,4]。甲壳素及壳聚糖的低聚物是指聚合度低于10的一些低聚葡聚糖,这些多糖具有优越的水溶性、保湿性。另外,D-低聚葡… 相似文献
16.
To investigate the genetic structures and differentiation of different wild populations of white croaker （Pennahia argentara）, horizontal starch gel electrophoresis was performed on 133 individuals collected from five different locations in China and Japan. The eleven enzyme systems revealed 15 loci, of which eleven were polymorphic. The percentage ofpolymorphic loci of white croaker populations varied from 6.67% to 53.3.3%; the mean observed and expected heterozygosity ranged from 0.0033 to 0.0133 and 0.0032 to 0.0191, respectively. The expected heterozygosity revealed a low genetic variability for white croaker in comparison with other marine fishes. The genetic distances between populations ranged from 0.00005 to 0.00026. A weak differentiation was observed within each clade and between clades; and no significant differences in gene frequencies among populations were observed in white croaker. Among the five populations, three Chinese populations showed more genetic diversity than that in Japanese populations. 相似文献
17.
甘蔗品种性状与过氧化物酶同工酶的关系 总被引：4，自引：0，他引：4
以３０个甘蔗品种为材料,用垂直平板聚丙烯酰胺凝胶电泳方法,对过氧化物酶同工酶进行分析,统计中酶带出现的频率与甘蔗主要性状的关系。结果表明：Ａ６、Ｂ３酶带同时出现时１００％为高糖品种,因此Ａ６、Ｂ３酶带与高糖性状关系极为密切;Ａ６、Ｂ８、Ｂ３、Ｂ７酶带单独存在时也与高糖性状有关;早熟种与Ａ６、Ｂ３、Ｂ７酶带的存在有关;中小茎种和中茎种分别与Ａ４、Ｂ５酶带的存在有关。 相似文献
18.
Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order
to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg2+) (at two final concentrations of 0.0025 and 0.0050 mg L−1, prepared with HgCl2) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant
enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills
and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation
with Hg2+ dose and time in the hepatopancreas and a negative correlation with Hg2+ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire
experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during
the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the
detoxification strategies against Hg2+ in three tissues of C. japonica. 相似文献
19.
采用单因素和正交优化实验19（43）确定酶法自溶罗非鱼下脚料的最适条件，结果表明，最适自溶条件为：料液质量比1：3，反应温度50％，pH7．5，反应时间6．5h；酶解结束蛋白质回收率为81．75％。 相似文献
20.
罗非鱼下脚料自溶条件的初步探讨 总被引：3，自引：0，他引：3
采用单因素和正交优化实验L9(43)确定酶法自溶罗非鱼下脚料的最适条件,结果表明,最适自溶条件为:料液质量比1∶3,反应温度50℃,pH7.5,反应时间6.5h;酶解结束蛋白质回收率为81.75%。 相似文献