共查询到20条相似文献，搜索用时 15 毫秒
1.
昆布寡糖对2型糖尿病大鼠的实验作用 总被引：1，自引：0，他引：1
从沿海藻类昆布(Thallus laminariae)中提取昆布多糖,经降解后得昆布寡糖。采用高脂饲料加小剂量链脲佐菌素法诱导SD大鼠2型糖尿病动物模型,成模后大鼠分为正常对照组,阴性对照组,二甲双胍组,昆布寡糖高、中、低剂量组,灌胃给予寡糖溶液8周,定期观察体重并采集血液标本进行检测。结果表明,昆布寡糖对糖尿病大鼠有明显的降低血糖,升高胰岛素,增加体重,降低甘油三酯、总胆固醇、游离脂肪酸,升高高密度脂蛋白胆固醇的作用,但对低密度脂蛋白胆固醇的影响不明显。可见,昆布寡糖对2型糖尿病大鼠具有明显治疗作用。 相似文献
2.
Sato Minoru Oba Takashi Hosokawa Takao Yamaguchi Toshiyasu Nakano Toshiki Saito Tadao Muramoto Koji Kahara Takashi Funayama Katsura Kobayashi Akio Nakano Takahisa 《中国海洋大学学报(英文版)》2005,4(3)
1 IntroductionIncreased blood pressure appears to be one of theprimary risk factors of circulatory organ diseases suchas encepharo-apoplexy, encepharo-infarction and cardi-ac infraction. Angiotensin-I-converting enzyme (ACE)plays an important role in the rennin-angiotensin sys-tem by regulating blood pressure. Antihypertensivedrugs such as captopril and enalapril are potent ACEinhibitors (Ondetti et al., 1977). Recently, severalinhibitory peptides derived from food proteins havebeen isolat… 相似文献
3.
Sato Minoru Oba Takashi Hosokawa Takao Yamaguchi Toshiyasu Nakano Toshiki Saito Tadao Muramoto Koji Kahara T akashi Funayama Katsura Kobayashi Akio Nakano Takahisa 《中国海洋大学学报(英文版)》2005,4(3):209-213
Brown alga （ Undaria pinnatifida） was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme （ACE） was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats （SHRs）. The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by pro- tease S ＇ Amano＇ （from Bacillus stearothermophilus） at the concentration of 10 （mg protein） （kg body weight）^ - 1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans. 相似文献
4.
Analgesis and wound healing effect of chitosan and carboxymethyl chitosan on scalded rats were investigated. A II degree scald model was established in rats, which was subsequently treated with chitosan and carboxymethyl chitosan solution, respectively. The concentration of bradykinin and 5-hydroxytryptophan was detected by assaying enzyme-linked immunosorbent. Healing condition was observed and pathological sections were made to determine the healing effect of chitosan and carboxymethyl chitosan. Results showed that the concentration of bradykinin and 5-hydroxytryptophan peaked at the third hour post-wound in all groups, while the concentration of hydroxyproline peaked at the seventh day post-wound in both chitosan and carboxymethyl chitosan group. The concentration of bradykinin and 5-hydroxytryptophan of carboxymethyl chitosan group was significantly lower than that of control (P < 0.05), while that of chitosan group was similar to that of control (P > 0.05). These findings indicated that carboxymethyl chitosan reduced the concentration of algogenic substances, resulting in analgesia. During the whole recovery process, the hydroxyproline concentration in chitosan and carboxymethyl chitosan group on day 3 and 7 was significantly higher than that of control (P < 0.01); however the significance of such a highness decreased on day 14 (P < 0.05). These findings indicated that chitosan and carboxymethyl chitosan accelerated tissue repair. Meanwhile, chitosan performed better in healing than carboxymethyl chitosan in both decrustation and healing time. In conclusion, carboxymethyl chitosan showed significant analgesis and wound-healing promotion effect, but chitosan only showed wound-healing promotion effect. 相似文献
5.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｍａｊｏｒｓｐｅｃｉｅｓｏｆｇｒｏｕｐｅｒ,Ｅｐｉｎｅｐｈｅｌｕｓｓｐ.ｂｅｉｎｇｍａｒｉｃｕｌｔｕｒｅｄｉｓｖｅｒｙｈｉｇｈｌｙｐｒｉｃｅｄａｎｄｐｏｐｕｌａｒｉｎＣｈｉｎａａｎｄＳｏｕｔｈｅａｓｔＡｓｉａ,ｂｕｔｕｐｔｏｎｏｗ ,ａｓｃｏｍｍｅｒｃｉａｌｆｅｅｄｉｓｓｔｉｌｌｎｏｔａｖａｉｌａｂｌｅｉｎｔｈｅｇｒｏｕｐｅｒｍａｒ ｉｃｕｌｔｕｒｅｉｎｄｕｓｔｒｙ,ｔｈｅｙｈａｖｅｔｏｂｅｆｅｄｗｉｔｈｆｒｏｚｅｎｔｒａｓｈｆｉｓｈａｓｍａｉｎｄｉｅｔ,ｓｏｉｔｉｓｈａｒ… 相似文献
6.
ThisworksupportedbytheScienceandTechnologyCommitteeofShandongProvince.Grant(95)50.INTRODUCTIONManyinvestigationsindicatalthatsupplementation0fsuitableseleniumleveIstolowordefidentinseleniumdietcanpreventoccurrenceofvarioustumots(Chen,l990),enhanceorganisminimneability(Wu,l992),maintainthenormalfunCtion0fheart,liv-er,lungandstomach(Schwarzetal,l957),andisgoodpareuti0nsagainstcardiovascularandcerebrovascu1arproblemsinoldpeople.Seleniumisanessentialtraeeelernentfornonnalhumanlife(Balassa… 相似文献
7.
8.
Chitosan composites and derivatives have gained wide attentions as effective biosorbents due to their low costs and high contents of amino and hydroxyl functional groups. They have showed significant potentials of removing metal ions, dyes and proteins from various media. Chemical modifications that lead to the formation of the chitosan derivatives and chitosan composites have been extensively studied and widely reported in literatures. The aims of this review were to summarize the important information of the bioactivities of chitosan, highlight the various preparation methods of chitosan-based active biosorbents, and outline its potential applications in the adsorption of heavy metal ions, dyes and proteins from wastewater and aqueous solutions. 相似文献
9.
The disease resistance and humoral immunomodulatory effects of vitamin C administered orally to grouper,Epinephelus awoara maintained on a frozen fish diet supplemented with vitamin C at 500, 1000, 1500 and 2000 mg/kg were investigated. After 20
weeks, the growth rates of the groups with high level of vitamin C apparently increased. The untreated fish had symptoms of
vitamin C deficiency. The endogenous liver tissue vitamin C levels were found to reflect well the dietary treatments. After
intraperitoneal injection or bath challenge with a virulent strain ofVibrio vulnificus, fish fed with high level vitamin C showed significantly higher survival rate compared with the normal control group. Vaccination
with formalin inactivatedV. vulnificus significantly enhanced the specific antibody production in fish treated with vitamin C, and completely protected from strong
bacterial challenge the groups fed on fish with vitamin C 1500 and 2000 mg/kg diet.
Project 39500113 supported by NSFC and also by Guangdong Science Research Foundation (Grant No. 950711). 相似文献
10.
Hongxia Che Jie Cui Min Wen Jie Xu Teruyoshi Yanagita Qi Wang Changhu Xue Yuming Wang 《中国海洋大学学报(英文版)》2018,17(2):392-398
The bioavailability of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) depends on their chemical forms. This study investigated the long-term effects of DHA-bound triglyceride (TG-DHA), DHA-bound phospholipid (PL-DHA), and the combination of TG-DHA and egg yolk phospholipid (Egg-PL) on lipid metabolism in mice fed with a high-fat diet (fat levels of 22.5%). Male C57BL/6J mice were fed with different formulations containing 0.5% DHA, including TG-DHA, PL-DHA, and the combination of TG-DHA and Egg-PL, for 6 weeks. Serum, hepatic, and cerebral lipid concentrations and the fatty acid compositions of the liver and brain were determined. The concentrations of serum total triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), and hepatic TG in the PL-DHA group and the combination group were significantly lower than those in the high-fat (HF) group (P < 0.05). Atherogenic index (AI) of the PL-DHA group was significantly lower than that of the combination group (P < 0.05). Hepatic TC level in the combination group was significantly lower than that in the HF group (P < 0.05), but no significant difference was observed between the combination group and the PL-DHA group. Both the PL-DHA and the combination groups showed significantly increased DHA levels in the liver compared with the HF group (P < 0.05). However, there were no obvious increases in the cerebral DHA levels in all DHA diet groups. These results suggest that PL-DHA was superior to the combination of TG-DHA and Egg-PL in decreasing the AI. Long-term dietary supplementation with low amount of DHA (0.5%) may improve hepatic DHA levels, although cerebral DHA levels may not be enhanced. 相似文献
11.
新型壳聚糖季铵盐衍生物的合成与表征 总被引：2，自引：0，他引：2
采用甲磺酸作为溶剂兼作氨基保护试剂,对壳聚糖上的羟基选择性酯化,再游离出氨基并对其氯乙酰化,最后进行吡啶成盐,得到新型水溶性的壳聚糖季铵盐衍生物,产物的结构通过核磁共振氢谱和红外光谱进行了表征,从而为壳聚糖季铵盐衍生物的制备提供了一种新途径。 相似文献
12.
Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0–29.0°C for 8 weeks. The controls were fed to satiation twice
a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks,
and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship
between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration
during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that
of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls.
Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the
whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved
digestibility, feed efficiency, or protein and energy retention efficiency.
Supported by the State Key Laboratory of Freshwater Ecology and Biotechnology of China and Shanghai Fisheries University (Grant
No. 200015). 相似文献
13.
《中国海洋大学学报(英文版)》2015,(5)
Chitosan, an excellent biomedical material, has received a widespread in vivo application. In contrast, its metabolism and distribution once being implanted were less documented. In this study, the pharmacokinetics and biodegradation of fluorescein isothiocyanate(FITC) labeled and muscle implantation administrated chitosan in rats were investigated with fluorescence spectrophotometry, histological assay and gel chromatography. After implantation, chitosan was degraded gradually during its distribution to diverse organs. Among the tested organs, liver and kidney were found to be the first two highest in chitosan content, which was followed by heart, brain and spleen. Urinary excretion was believed to be the major pathway of chitosan elimination, yet 80% of chitosan administered to rats was not trackable in their urine. This indicated that the majority of chitosan was degraded in tissues. In average, the molecular weight of the degradation products of chitosan in diverse organs and urine was found to be 65 k Da. This further confirmed the in vivo degradation of chitosan. Our findings provided new evidences for the intensive and safe application of chitosan as a biomedical material. 相似文献
14.
ZHAO Xia * LV Zhihua XU Jiamin YU Guangli Insititute of Marine Drug Food Ocean University of China Qingdao P..R.China 《中国海洋大学学报(英文版)》2003,2(1):69-74
1 Introduction Derivativesofchitosansulfateareknowntohaveimportantantithrombin (Drozdetal.,2 0 0 1;Hagiwaraetal.,1999;Tuetal.,1999) ,antiarteriosclerotic(Dingetal.,2 0 0 1;Gamzazadeetal.,1997) ,an timetastatic (Murataetal.,1990 )andantiviral(Nishimuraetal.,1998) pharmacologicalactivitiesduetotheirsimilarskeletalstructuretoheparinandtheirtypicalpolyanionproperties .Furthermore ,theyplayimportantrolesinwoundhealing ,tumorgrowthandangiogenesis ,dependingonthetypeoffunctionalgroups,theamountan… 相似文献
15.
北京大气细粒子及其成分的浓度变化特征 总被引：4，自引：0，他引：4
硫酸盐、硝酸盐是城市的大气细粒子重要组成部分之一。本文利用RCFP仪器针对北京市2004～2007年北京大气细粒子的成分进行了连续的观测与分析发现,硝酸盐年平均下降率为7%,约合0.7微克/立方米;而硫酸盐浓度从2006年的28微克/立方米下降到了18微克/立方米。同时特别分析了2007年8月17日至20日机动车限行期间,北京及周边地区区域气象特征、细颗粒污染物浓度特征,及其主要化学成分的特征,并参照反向轨迹演算发现以硫酸盐为表征的北京周边地区污染物随弱南向气团向北京输移,以湿气团和氯离子为共同表征的东南海陆特性气团随东南气流向北京输移,从而证明偏南气流将北京周边地区的细颗粒物污染物输移向北京的特征。 相似文献
16.
Glucosamine sulfate was prepared from glucosamine hydrochloride that was produced by acidic hydrolysis of chitin by ion-exchange method. Optical rotation and elemental analysis characterized the degree of its purity. In addition, the antioxidant potency of chitosan derivative-glucosamine sulfate was investigated in various established in vitro systems, such as superoxide (O-2)/hydroxyl (·OH) radicals scavenging, reducing power, iron ion chelating. The following results are obtained: first, glucosamine sulfa... 相似文献
17.
SYNTHESIS AND PROPERTIES OF SULFHYDRYL CHITOSAN 总被引：1，自引：0，他引：1
A new adsorbent for heavy metal ions, sulfhydryl chitosan (S-chitosan), was produced by treatment of chitosan with sulhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confrrmed by elemental analysis and FI‘-IR spectra analysis. The adsorption properties of sulthydryl chitosan for Cu(Ⅱ ), Cd(Ⅱ ), Pb(Ⅱ), Cr(Ⅲ) and Ni(Ⅱ) were investigated, and the effect of pH value on adsorption, adsorption kinetics, and selective adsorption was examined. It was shown that S-chitosan has good adsorption for Pb(Ⅱ), Cu(Ⅱ) and Cd(Ⅱ) like chitosan, is also insoluble in acid solution; has good adsorption kinetic properties for heavy metal ions; and can be used in acid solution. The adsorption capacities of S-chitosan can be affected by media acidity. The adsorbed Cu(Ⅱ) Cd(Ⅱ) and Pb(Ⅱ) could be eluted by diluted chlorhydric acid. 相似文献
18.
Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different. 相似文献
19.
Chitosan derived from crab shells,was used to prepare the graft polymer in aqueous solution with acrylamide (AM) and methacrylatoethyl trimethyl ammonium chloride (DMC) as raw materials and ceric ammonium nitrate (CAN) as initiator.The floc-culation ability of the resulting polymer (PCAD) was studied in waste water treatment experiments.Its properties were determined on the basis of the transmittance of waste water after flocculation.The effects of chitosan and DMC content on PCAD’s flocculation ability wer... 相似文献
20.
This study investigated the removal of heavy metal ions from cigarette mainstream smoke using chitosan. Chitosan of various deacetylation degrees and molecular weights were manually added to cigarette filters in different dosages. The mainstream smoke particulate matter was collected by a Cambridge filter pad, digested by a microwave digestor, and then analyzed for contents of heavy metal ions, including As(III/V), Pb(II), Cd(II), Cr(III/VI) and Ni(II), by graphite furnace atomic absorption spectrometry (GFAAS). The results showed that chitosan had a removal effect on Pb(II), Cd(II), Cr(III/VI) and Ni(II). Of these, the percent removal of Ni(II) was elevated with an increasing dosage of chitosan. Chitosan of a high deace tylation degree exhibited good binding performance toward Cd(II), Cr(III/VI) and Ni(II), though with poor efficiency for Pb(II). Except As(III/V), all the tested metal ions showed similar tendencies in the growing contents with an increasing chitosan molecular weight. Nonetheless, the percent removal of Cr(III/VI) peaked with a chitosan molecular weight of 200 kDa, followed by a dramatic decrease with an increasing chitosan molecular weight. Generally, chitosan had different removal effects on four out of five tested metal ions, and the percent removal of Cd(II), Pb(II), Cr(III/VI) and Ni(II) was approximately 55%, 45%, 50%, and 16%, respectively. In a word, chitosan used in cigarette filter can remove toxic heavy metal ions in the mainstream smoke, improve cigarette safety, and reduce the harm to smokers. 相似文献