多棘海盘车体壁胶原蛋白的研究

采用两种不同的方法从海盘车体壁中提取出酸溶性胶原蛋白（ＡＳＣ）和胃蛋白酶促溶的胶原蛋白（ＰＳＣ）,得率分别为１０．９０％、６１．４３％。将ＡＳＣ、ＰＳＣ的氨基酸组成、理化性质与脊椎动物及其它无脊椎动物胶原蛋白进行比较,结果表明,ＡＳＣ、ＰＳＣ是典型的胶原蛋白。在此基础上对ＡＳＣ、ＰＳＣ进行了ＳＤＳ－ＰＡＧＥ电泳,进一步表明制品的纯度较高,并且它们在分子大小、构型及性质上没有显著差异。     

鲢鱼鳞片胶原蛋白的提取

利用酸和酶提取法,从淡水鲢鱼鳞片中提取酸溶性和酶溶性胶原蛋白.经紫外光谱分析显示,所提取的胶原蛋白与I型胶原蛋白标准品接近.氨基酸组成分析表明,ASC和PSC是典型的Ⅰ型胶原蛋白.     

鲢鱼鳞片胶原蛋白的提取

利用酸和酶提取法,从淡水鲢鱼鳞片中提取酸溶性和酶溶性胶原蛋白.经紫外光谱分析显示,所提取的胶原蛋白与I型胶原蛋白标准品接近.氨基酸组成分析表明,ASC和PSC是典型的Ⅰ型胶原蛋白.     

草鱼鱼鳞酶溶性胶原蛋白的提取及基本特性

利用胃蛋白酶从草鱼鱼鳞中提取酶溶性胶原蛋白(PSC)。并用氨基酸自动分析仪、SDS-PAGE电泳、DSC、FT-IR和圆二色谱对草鱼鱼鳞胶原蛋白的氨基酸组成、相对分子量、变性温度和结构进行了研究。试验结果表明:所提草鱼鱼鳞蛋白为典型的I型胶原蛋白;且至少含有2条α链,α1和α2链;DSC分析表明其变性温度为37.1℃。     

草鱼鱼鳞胶原蛋白的提取及其部分生物学性能

以草鱼鱼鳞为原料, 分别提取鱼鳞中的酸溶性胶原蛋白(ASC)和酶溶性胶原蛋白(PSC), 着重开展了其包括热稳定性、体外酶降解性以及胶原海绵材料特性在内的相关研究, 并与哺乳动物来源的猪皮胶原(PC)相比较。实验结果表明, 制备所得的3种胶原蛋白均为典型的Ⅰ型胶原并具有完整的三螺旋结构; PC的热变性温度(41.6 ℃)明显高于ASC(34.8 ℃)和PSC(35.2 ℃); 3种胶原蛋白的体外酶降解性能受水解酶的种类、胶原蛋白提取方法、胶原蛋白来源、胶原蛋白受热历史以及蛋白的自组装程度影响。胶原蛋白酶、胰蛋白酶和木瓜蛋白酶对淡水鱼胶原均具有不同程度的降解能力, 但胶原蛋白酶的降解能力最强; 相同条件下, 3种胶原蛋白体外酶降解率依次为ASC>PSC>PC; 经热变性处理后胶原蛋白的体外酶降解率明显提高而经体外自组装处理后其体外酶降解率均出现不同程度的降低; 3种胶原样品冻干后得到的胶原海绵材料具有不同的机械性能和组织结构, ASC和PSC海绵是一种多孔但拉伸承受力较弱的海绵材料, 而PC则与之相反。     

鲈鱼骨酸溶性和酶溶性胶原的性质比较

以鲈鱼骨为原料提取得到酸溶性胶原(ASC)和酶溶性胶原(PSC),对ASC和PSC的性质进行比较。粘度测定结果表明,ASC的变性温度25~30℃,PSC的变性温度为30~35℃;电泳结果表明,ASC和PSC都属于Ⅰ型胶原且纯度比较高;氨基酸分析结果显示,羟脯氨酸和脯氨酸含量ASC均低于PSC,氨基酸检测结果与粘度检测结果相一致。     

栉孔扇贝血淋巴中ACP和AKP活性及其电镜细胞化学研究↑（*）

用电镜细胞化学和分光光度技术对栉孔扇贝血淋巴中的酸性磷酸酶（ＡＣＰ） 和碱性磷酸酶（ＡＫＰ） 的研究结果表明,溶酶体呈强的ＡＣＰ 阳性;ＡＫＰ 阳性颗粒常沿细胞膜分布;部分细胞ＡＣＰ 阳性颗粒较多,且靠近细胞膜,胞浆中也有分布。生化测定结果表明,血细胞和血清中均存在ＡＣＰ和ＡＫＰ 活性,且血清中的２ 种酶的酶活力均高于血细胞中,血清中ＡＣＰ和ＡＫＰ 的最适ｐＨ 分别为４ ．４ 和１０ ．３ ,最适温度分别为３５ ℃和５５ ℃。     

鳜鱼病毒核酸随机引物扩增与克隆↑（*）

从感染鳜鱼病毒（ Ｓｉｎｉｐｅｒｃａ ｃｈｕａｔｓｉ Ｖｉｒｕｓ,简称ＳＣＶ） 的鳜鱼体中分离病毒,提纯核酸作模板。通过ＲＡＰＤ 法,用带酶切位点的引物进行病毒核酸随机引物扩增,获得扩增带谱。从带ＥｃｏＲⅠ酶切位点的引物扩增产物中,用琼脂糖凝胶电泳回收大小约为０ ．４ 和０ ．５ Ｋｂｐ 的片段,经ＥｃｏＲⅠ酶切处理制备成带粘性末端的片段,分别插入质粒ｐＵＣ１９ 的ＥｃｏＲⅠ位点。ＥｃｏＲⅠ酶对重组子进行了酶切鉴定,获得２ 种带插入ＳＣＶ 核酸ＰＣＲ扩增产物的重组子。     

低酶水解法提取无苦味鳀鱼水解蛋白

低酶水解法提取无苦味鳀鱼水解蛋白王长云，薛长湖，陈修白（青岛海洋大学水产学院，２６６００３）关键词鳀鱼，水解蛋白，无苦味，低酶水解法ＰＲＥＰＡＲＡＴＩＯＮＯＦＦＩＳＨＮＯＮ－ＢＩＴＴＥＲＨＹＤＲＯＬＹＳＡＴＥＦＲＯＭＡＮＣＨＯＶＹ（ＥＮＧＲＡＵＬＩＳ...     

大鲵皮肤中胶原蛋白的初步提取分析与应用研究

正中国大鲵(Andrias davidianus Blanchard)俗名"娃娃鱼",属于两栖纲、有尾目、隐鳃鲵科,为国家二级保护动物。目前,顾赛麒等在低温4℃条件下,采用酸法(0.5摩尔/升乙酸)和酶法(胃蛋白酶)对人工养殖大鲵皮中的胶原蛋白进行了提取,对提取纯化后经过测定为Ⅰ型胶原蛋白。李华在低温4℃条件下使用酶解工艺提取养殖大鲵皮中的胶原蛋白紫外     

Isolation and characterization of collagens from the skin of giant grouper (Epinephelus lanceolatus)

ABSTRACT

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were extracted from the skin of giant groupers (Epinephelus lanceolatus) with yields of 39.51 and 19.12%, respectively. ASC and PSC consisted of two different α chains (α1 and α2) and were characterized to be type I collagen with no disulfide bond. The imino acid contents of the ASC and PSC from giant grouper skin were 189 and 181 per 1,000 residues, respectively. The maximum endothermic temperatures (T_max) of ASC and PSC measured by differential scanning calorimetry (DSC) were 31.71 and 31.33°C, respectively. The denaturation temperatures of ASC and PSC measured by viscometry were 29.84 and 29.05°C, respectively. The maximum solubility in 0.5 M acetic acid was observed at pH 5 and pH 6 for ASC and PSC, respectively. A sharp decrease in solubility was observed for both ASC and PSC in the presence of NaCl above 3% (w/v).     

鲤鱼鱼鳞胶原蛋白ASC与PSC的比较

以鲤鱼鱼鳞为原料,研究了酸法和酶法提取的鱼鳞胶原蛋白ASC和PSC的异同.经过SDS-凝胶电泳和氨基酸分析可以看出,2种蛋白在分子构型、氨基酸组成等方面的差异并不明显,经过蛋白酶K有限酶解后的图谱证明了这一点.但从差热分析,以及蛋白质受热的分解变化来看,二者之间在热稳定性方面存在一定的差异.推测差距产生的原因与蛋白质制备过程中,胃蛋白酶的作用有关,胶原蛋白两端的非螺旋区域受到酶的作用而分解,非螺旋区域对三螺旋的稳定性起着重要作用,非螺旋区域的分解大大降低了PSC对热的耐受性.     

Characteristics and Select Functional Properties of Collagen from Golden Pompano (Trachinotus ovatus) Skins

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) from golden pompano skins were extracted and characterized. The molecular weight of ASC was about 130 kDa for α₁ and 115 kDa for α₂, which were slightly higher than those of PSC. Similar amino acid composition and Fourier transform infrared (FTIR) spectra were observed in both collagens, but slight differences were found in the peptide maps of collagen digested by V8 protease and trypsin. The denaturation temperatures (Tds) of ASC and PSC calculated from the reduced viscosity were 31.8 and 30.0°C, while the transition temperature (T_m) of ASC and PSC analyzed by DSC were 33.0 and 32.0°C, respectively. ASC has a lag phase, a growth phase, and a plateau phase in the turbidity–time curve, while PSC does not have similar phenomenon. It was found that the fibril gel of ASC could be formed at 25°C, leading to improved thermal stability.     

Characteristics of Collagen from Rohu (Labeo rohita) Skin

Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were isolated from rohu skin with the yield of 64.2 and 6.8% (dry weight basis), respectively. Both collagens had glycine as the major amino acid with imino acid content of 196–202 residues/1,000 residues and were characterized as type I collagen with molecular composition of (α1)₂α2-heterotrimer. Fourier transform infrared spectra of both collagens were similar, with no shift in wavenumber of all amide bands. The T_max value of ASC and PSC was 36.40 and 35.48°C, respectively. The zero surface net charge of ASC and PSC was found at pH 5.9 and 5.3, respectively.     

Pyridinoline concentrations in muscular and skin collagen of fish and relationship between collagen solubility and pyridinoline concentration in fish muscular collagen

Pyridinoline (Pyr), one of the mature crosslinks of collagen, was determined in muscular collagen of three species of fish. The amounts of muscular Pyr in red sea bream, yellowtail, and tiger puffer were 3.4, 8.8, and 50.3 mmol/mol collagen, respectively, indicating that the Pyr concentration in muscular collagen differs greatly among fish species. The Pyr concentration in tiger puffer muscular collagen was the greatest, but it was only one-fourth that in rabbit muscle. As in mammalian skin collagen, Pyr was not detected in skin collagen of red sea bream and yellowtail. However, tiger puffer skin contained Pyr (3.75 mmol/mol collagen). The presence of Pyr would have a relationship to some features of tiger puffer skin, such as mechanical strength and thickness. Pyr concentrations in acid-soluble collagen (ASC), pepsin-solubilized collagen (PSC), and insoluble collagen (ISC) in muscles of three species of fish were determined. Pyr was found in ISC > PSC > ASC, from the highest to the lowest concentration, and the concentration in ISC was 45–200 times that in ASC. Therefore, Pyr crosslinks that are formed between collagen molecules would have a close relationship to collagen solubility.     

Isolation and Characterization of Pepsin-Soluble Collagen from the Skin of Peru Squid (Dosidicus gigas)

Pepsin-soluble collagen (PSC) was isolated from Peru squid (Dosidicus gigas) skin and physicochemical properties of the PSC were determined. The PSC exhibited a maximum absorbance at 220 nm. Sodium dodecyl sulfate polyacrylamide gel electrophoresis suggested the collagen containing α1 and α2 chain was classified as type I collagen. Amino acid composition indicated that the collagen had lower amino acid content than that of mammalian collagen. Denaturation temperature (T_d) of the PSC was 26.8°C. The PSC had relatively high solubility in alkaline condition or NaCl concentrations below 2%. Fourier transform infrared spectroscopy investigations showed the existence of helical arrangements of collagen. The lyophilized collagen had a uniform and regular network structure. These results suggested that Peru squid skin was a potential source of collagen for further research and application.     

Changes in muscle collagen content during <Emphasis Type="Italic">post mortem</Emphasis> storage of farmed sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis>): influence on textural properties

The changes in collagen content and its solubility in sea bream muscle were studied for variable storage times following the death of the fish, and these variables were related to the evolution of physical parameters important for consumer acceptance: firmness and water-holding capacity (WHC). The results show that the collagen content in muscle diminished slightly over storage time and that this variable was directly related to firmness but inversely related to the water-holding capacity. With regard to collagen solubility, a decline was detected in acid-soluble collagen (ASC) in the first few post mortem hours, perhaps related to the end of rigor mortis that occurs at these stages. Pepsin-soluble collagen (PSC) increased, while insoluble collagen (ISC) decreased from 96 h, coinciding with a loss of firmness. This softening can be explained as a result of specific collagenases acting on the insoluble fraction of the collagen.     

Characterization of Acid-Soluble Collagen From Bone of Pacific Cod (Gadus macrocephalus)

Acid-soluble collagen (ASC) was isolated from Pacific cod (Gadus macrocephalus) bone. The ASC was rich in glycine. The amount of imino acid was lower than that of calf skin collagen, as was the transition temperature (48.6°C). Electrophoresis revealed two different α chains (α₁ and α₂), β-component, and γ-component. Fourier transform infrared spectroscopy measurement showed that ASC was in triple-helix structure. ASC had a solubility greater than 90% in a very acidic pH range (pH 1–4), and the solubility decreased with increasing NaCl concentrations up to 3%. Lyophilized ASC had a network ultrastructure with lace-like fibers, similar to calf skin collagen sponge.