Preparation,characterization and antioxidant activity analysis of three Maillard glycosylated bone collagen hydrolysates from chicken,porcine and bovine

Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant activity.Maillard glycosylated reaction is considered as a promising method to enhance the antioxidant activity of peptides.Hence,this research aims at investigating the Maillard glycosylation activity and antioxidant activity of bone collagen hydrolysates from different sources.In this study,3 glycosylated bone collagen hydrolysates were prepared and characterized,and cytotoxicity and antioxidant activity were analyzed and evaluated.The free amino groups loss,browning intensity,and fluorescence intensity of G-Cbcp(glycosylated chicken bone collagen hydrolysates(peptides))were the heaviest,followed by G-Pbcp(glycosylated porcine bone collagen hydrolysates(peptides))and G-Bbcp(glycosylated bovine bone collagen hydrolysates(peptides)).The results of amino acid analysis showed that amino acid composition of different bone collagen hydrolysates was significantly different and the amino acid decreased to different degrees after Maillard glycosylated reaction,which may lead to differences in Maillard glycosylated reaction activity.Furthermore,the 3 glycosylated hydrolysates showed no significant cytotoxicity.The results showed that glycosylation process significantly increased the antioxidant activity of bone collagen hydrolysates,and G-Cbcp showed the strongest antioxidant activity,followed by G-Pbcp and G-Bbcp.Therefore,compared with the bone collagen hydrolysates,3 glycosylated hydrolysates showed significant characteristic and structural changes,and higher antioxidant activity.

Analysis of Molecular Weight Distribution and Antioxidant Activities of Cirrhinus molitorella Skin Collagen Hydrolysates

[Objective] The aim of this work was to identify molecular weight （MW） distribution and antioxidant activity of fish skin col agen hydrolysates. [Method] The MW distribution of hydrolysates was determined using both size exclusion chromatography and matrix-assisted laser desorption ionization time-of-flight mass spec-trometry （MALDI-TOF-MS）. Fish skin were treated by the alkaline protease 2709. [Result] The optional conditions for hyerolysis were time 3 h, temperature 55 ℃, pH 10.0, substrate concentration 80 g/L and E/S 4%. The results of both methods indi-cated that the molecular weight of col agen hydrolysates was from 400 to 1 800 Da, and the peptides’ molecular weight was less than 1 400 Da mostly. The reducing power and antioxidant/radical scavenging activity [1, 1-diphenyl-2-picryl-hydrazyl （DPPH） free radical scavenging activity] were determined. [Conclusion] The results reveal that the fishskin hydrolysate is a potential source of antioxidants.

Study on Enzymatic Hydrolysis of Gadus morrhua Skin Collagen and Molecular Weight Distribution of Hydrolysates

Process parameters on enzymatic hydrolysis and molecular weight （MW） distribution of collagen hydrolysates from Gadus morrhua skin were investigated. The optimal process parameters were obtained by the single-factor and orthogonal experiments. The molecular weight distribution of hydrolysates was determined using both Sephadex G25 partition and high speed liquid chromatography electricity spray mass spectrum （HPLC-ESI-MS）. Collagen hydrolysates were first gained by an alkaline protease ＂alcalase＂ for 3 h at temperature （50~C）, pH （10.0）, substrate concentration （75 g L-~）, and E/S （3%）. The molecular weight distribution of collagen hydrolysates ranged from 300 to 1 500 Da, and most of peptides were under 1 200 Da. Sephadex G25 partition and HPLC-ESI-MS should be successfully employed to determine the molecular weight distribution of collagen hydrolysates.

Amino Acid Composition and Functional Properties of Giant Red Sea Cucumber (Parastichopus californicus) Collagen Hydrolysates

Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis.The aim of this study was to evaluate the functional properties of collagen hydrolysates from this species.The degree of hydrolysis (DH),amino acid composition,SDS-PAGE,emulsion activity index (EAI),emulsion stability index (ESI),foam expansion (FE),and foam stability (FS) of hydrolysates were investigated.The effects of pH on the EAI,ESI FE and FS of hydrolysates were also inves-tigated.The results indicated that the β and α1 chains of the collagen were effectively hydrolyzed by trypsin at 50℃ with an En-zyme/Substrate (E/S) ration of 1:20 (w:w).The DH of collagen was up to 17.3% after 3 h hydrolysis with trypsin.The hydrolysates had a molecular weight distribution of 1.1 17 kDa,and were abundant in glycine (Gly),proline (Pro),glutamic acid (Glu),alanine (Ala) and hydroxyproline (Hyp) residues.The hydrolysates were fractionated into three fractions (< 3 kDa,3 10 kDa,and > 10 kDa),and the fraction of 3 10 kDa exhibited a higher EAI value than the fraction of > 10 kDa (P<0.05).The fraction of > 10 kDa had higher FE and FS values than other fractions (P<0.05).The pH had an important effect on the EAI,ESI,FE and FS.All the fractions showed undesirable emulsion and forming properties at pH 4.0.Under pH 7.0 and pH 10.0,the 3 10 kDa fraction showed higher EAI value and the fraction of > 10 kDa showed higher FE value,respectively.They are hoped to be utilized as functional ingredients in food and nutraceutical industries.

Supplementation with yak (Bos grunniens) bone collagen hydrolysate altered the structure of gut microbiota and elevated short-chain fatty acid production in mice

In this study, yak bone collagen hydrolysate(YBCH)was produced by mixed proteases and provided to standard-diet mice at a different dose(low dose(LD), medium dose(MD), and high dose(HD))to investigate its effects on the composition of gut microbiota and short-chain fatty acids(SCFA)production. It was found that YBCH was mainly composed of small molecular peptides whose molecular weight below 2 000 Da. Notably, supplementation with different doses of YBCH could significantly downregulate the ratio of Firmicutes to Bacteroidetes in the fecal microbiota. At the family level, the Lachnospiraceae abundance was significantly reduced in the YBCH gavage groups(mean reduction ratio 41.7 %, 35.2%, and 36.4% for LD, MD, and HD group, respectively). The predicted functions of gut microbes in the MD group were significantly increased at “lipid metabolism” and “glycan biosynthesis and metabolism”. Moreover, the SCFA production in the YBCH groups was elevated. Especially, the concentration of acetic acid, propionic acid, and butyric acid in the MD group was separately increased 79.7%, 89.2%, and 78.8% than that in the NC group. These results indicated that YBCH might be applied in the development of functional food for intestinal microecological regulation.

胶原水解物抗骨质疏松疗效功能的研究

解决骨质疏松导致的骨微观结构被破坏、骨密度下降的问题是目前全球老龄化背景下的一个研究热点。为了缓解骨质疏松,本研究使用来自细胞外基质的胶原水解物促进成骨和成血管,进而缓解骨质疏松。通过细胞活性分析,发现胶原水解物可以同时促进成骨细胞MC3T3-E1和内皮细胞EA.hy926的增殖,分别可达到141%、116%(P<0.05),通过碱性磷酸酶和茜素红S染色,发现胶原水解物能促进成骨细胞分化和矿化。建立了去势小鼠骨质疏松模型,micro CT表征发现胶原水解物能较为显著的抑制骨质疏松引起的骨小梁结构破坏,从而缓解骨质疏松症状。本研究表明胶原水解物在促进成骨、抑制骨质疏松等领域具有较大的应用潜力。

基于Lasso回归模型研究抗冻肽性质对冷冻鱼糜肌原纤维蛋白的影响

为探究抗冻肽性质对其保护冷冻鱼糜肌原纤维蛋白效果的影响,本实验对3种抗冻肽(丝胶肽、胶原肽及鲢鱼酶解产物)的性质进行表征,分析不同冻藏条件下鱼糜肌原纤维蛋白指标变化规律,并基于最小绝对缩小和选择算子(least absolute shrinkage and selection operator,Lasso)回归构建了“冻藏工艺-抗冻肽性质-肌原纤维蛋白指标”的关联模型。结果表明,所用的3种抗冻肽均为分子质量低(m<10000 Da)、亲水性强(静态接触角小于30°)的“超活性”抗冻肽(热滞活性大于0.60℃),极性氨基酸占比超过60%;所用抗冻肽能够显著减缓冻藏处理对肌原纤维蛋白的负面影响;冻藏处理后,抗冻肽组鱼糜肌原纤维蛋白含量平均值维持在50.44~54.47 mg/g,Ca^(2+)-ATPase活性平均值为1.61~1.67 U/mg,表面疏水性指数平均值相比新鲜鱼糜仅增长39.91%~42.40%,肌原纤维蛋白变性速率远低于未添加抗冻剂组。Lasso回归模型解释了抗冻肽性质对冷冻鱼糜肌原纤维蛋白变化的影响,证明低分子质量、高热滞活性的抗冻肽有助于减缓肌原纤维蛋白含量、Ca^(2+)-ATPase活性、表面疏水性及特征指数的劣变速率;抗冻肽亲/疏水性的区别导致其与冰晶和蛋白之间的相互作用不同,从而对鱼糜肌原纤维蛋白产生不同影响。本研究可为抗冻肽在冷冻鱼糜中的应用及鱼糜制品的品质调控提供理论基础,同时为研究新型高效的抗冻剂提供方向。

胶原蛋白水解物缓解去势小鼠骨质疏松作用机理的探究

胶原蛋白水解物被认为拥有促进成骨和成血管以及起到防止骨质疏松的作用。我们通过生物信息学和建立去势小鼠骨质疏松症模型探究了胶原水解物(CH)对骨质疏松症有益作用的潜在机制。本研究发现,CH可以使24个与骨质疏松和成血管相关基因差异表达,差异基因的富集分析确定了20个KEGG通路。通过对筛选的十个通路进行分析,并结合STITCH数据库的探究,发现了Kdr、Erbb2、Wnt3a、Jagl、Fltl为CH调控的中枢基因。特别是,MAPK信号通路被确定为共享通路中的潜在关键通路。这个研究结果表明,胶原蛋白水解物可以通过MAPK信号通路促进成血管并抑制骨质疏松。

Toxicity evaluation of collagen hydrolysates from chrome shavings and their potential use in the preparation of amino acid fertilizer for crop growth

Resource utilization of chrome shavings(CS)has attracted a lot of attention from scientists and technologists in leather industry.Especially,the collagen hydrolysates extracted from CS are expected to find potential application values in agricultural field.However,there is no biotoxicity analysis of collagen hydrolysates from CS.Herein,the collagen hydrolysates with different molecular weights were produced from CS by three hydrolysis dechroming methods including alkaline hydrolysis,enzymatic hydrolysis and alkaline-enzymatic synergistic hydrolysis,and the optimal hydrolysis process of CS was designed and conducted.To evaluate their toxicity,the three collagen hydrolysates were formulated into a nutrient solution for zebrafish development.The obtained results indicated that the hydrolysates with low concentrations(less than 0.6 mg/mL)were safe and could promote the development for zebrafish embryos.Furthermore,the three collagen hydrolysates were utilized as organic nitrogen sources and formulated into amino acid water-soluble fertilizers(AAWSF)including alkaline type fertilizer(OH),enzymatic type fertilizer(M)and alkaline-enzymatic type fertilizer(OH-M)for the early soilless seeding cultivation of wheat,soybean and rapeseed.It is worth mentioning that the chromium contents in the prepared AAWSF were less than 10 mg/kg,which is far less than the limit value in the standard(China,50 mg/kg).The growth and development of seedlings(germination rate,plant height,fresh weight of leaves,soluble sugar content and chlorophyll content)were investigated.The corresponding results showed that the growth of seedlings watered with AAWSF was better compared with the other treatments,and the OH-M fertilizer had the best promoting effect on the seedlings growth and development,followed by the M and OH fertilizers.The safe toxicity assessment of the collagen hydrolysates will expand their application scope,and the use of collagen hydrolysates extracted from CS for seedlings growth also provides an effective and reason-able way to deal with the chromium-containing leather solid waste,which is an effective way to realize its resource utilization.

Developments for collagen hydrolysates as a multifunctional antioxidant in biomedical domains

Antioxidant collagen hydrolysates refers to the peptides mixture with antioxidant properties identified from hydrolyzed collagen.Due to its specific structural,biological and physicochemical properties,collagen hydrolysates have been explored as a multifunctional antioxidant in the biomedical field.In this review,we summarize recent advances in antioxidant collagen hydrolysates development.Initially,the preparation process of antioxidant collagen hydrolysates is introduced,including the production and separation methods.Then the effects and the mechanisms of amino acid composition and collagen peptide structure on the antioxidant activity of collagen hydrolysates are reviewed.Finally,the applications of antioxidant collagen hydrolysates in biomedical domains are summarized,with critical discussions about the advantages,current limitations and challenges to be resolved in the future.

Osteogenic peptides in collagen hydrolysates:Stimulate differentiation of MC3T3-E1 cells viaβ1 integrin-FAK-ERK1/2 signaling pathway and Smad1 protein

Our previous study demonstrated that orally administration of collagen hydrolysates from silver carp skin(SCH)could increase bone remodeling in chronologically aged mice.However,the active compounds and molecular mechanism were still unclear.In this study,SCH showed strong activity in promoting osteogenic differentiation of MC3T3-E1 cells and the active components in it were separated by ultrafiltration and YMC ODS-A C18 column.And then,a series of peptides containing potential osteogenic sequences were identified by LC-MS/MS and two novel peptides,GARGDKGETGEAGE(GE-14)and TGPRGPVGPA(TA-10),were synthesized for further investigation.The results indicated that peptides GE-14 and TA-10 could promote the differentiation and mineralization of MC3T3-E1 cells by positively regulatingβ1 integrin-FAK-ERK1/2 and Smad1 pathway,which might be due to the RGD or GPR sequences in them.These findings suggest that SCH has the potential to be developed as an effective diet supplement to prevent osteoporosis.

胶原、明胶和水解胶原蛋白的性能差异

由于胶原、明胶和水解胶原蛋白制备工艺的差异,造成它们在结构和性能上存在较大的差别。用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)方法确定3种样品的相对分子质量及其分布。结果表明:胶原的相对分子质量大约为30万,分布很窄;明胶的相对分子质量从几千到10万,分布很宽;水解胶原蛋白相对分子质量从几千到3万,分布也很宽。3种样品中只有胶原和明胶能够成膜,但是胶原膜的抗张强度(58N/mm2)大于明胶膜(36N/mm2),并且只有胶原膜在扫描电子显微镜(SEM)下呈现出纤维结构。纤维成形实验表明只有胶原才具有成纤维能力。角质形成细胞培养实验证明了只有胶原有利于细胞的吸附和生长,明胶和水解胶原蛋白与培养皿培养的参比样相似,都对细胞的吸附和生长无明显的促进作用。由此得出结论:只有胶原才有生物活性,具有比明胶和水解胶原蛋白更大的潜在生物医学用途。

碱法水解脱铬革屑制备胶原蛋白水解物的研究

采用碱法水解脱铬革屑制备胶原水解产物 ,研究了影响胶原水解产物收获率的各种因素 ,得出的结论为 :碱法水解的最佳条件为CaO用量 4% (w/w)、反应时间lh、反应温度 60℃、水 -渣比 7,在此条件下 ,胶原水解产物的收获率为 5 5 .0 3 % ,分子量分布在 1 6.1 0kDal左右。

茚三酮比色法和甲醛滴定法测定水解胶原的比较

研究了茚三酮比色法和甲醛滴定法测定氨基酸含量的线性检测范围、检测精密度和准确度。结果表明:茚三酮比色法的线性检测范围为0.5～6mg/L,最低可检测浓度为0.5mg/L,测定浓度范围广;甲醛滴定法最低可检测浓度为2g/L,适合测定高浓度样品。2种方法的相对标准偏差(RSD)<2.5%,回收率在98%～103%之间,表明这2种检测方法均具有较好的重复性和较高的准确度。这2种方法用于胶原水解产物测定时,茚三酮比色法的测定值总是低于甲醛滴定法的测定值,这是由于胶原水解产物的脯氨酸和羟脯氨酸含量较高,而这2种氨基酸在茚三酮比色法测定波长568nm处,无最大吸收峰。

梅花鹿茸胶原酶解物对去势大鼠骨质疏松症防治作用的实验研究(英文)

观察梅花鹿茸胶原酶解物(CSDV)对去势大鼠骨质疏松症防治作用的实验研究。通过对模型组、给药组和假手术组在形态计量学指标,生物力学指标和血清生化指标的评价,考察鹿茸胶原酶解物的作用。结果表明CSDV能够明显提高去势骨质疏松症大鼠骨密度,调节血清碱性磷酸酶水平和骨钙素水平。说明鹿茸胶原酶解物在防治去势大鼠骨质疏松症方面具有明显作用。

鱼鳞水解胶原蛋白在蛋糕和灌肠中的应用

通过蛋糕焙烤和灌肠加工实验,对鱼鳞水解胶原蛋白在蛋糕和灌肠中的应用效果进行研究。结果表明,适量添加鱼鳞水解胶原蛋白可以提高蛋糕的成品率和蛋糕的比容,增加灌肠制品的成品率,提高灌肠的持水力,并能获得感官品质良好的蛋糕和灌肠制品。在本实验条件下,鱼鳞水解胶原蛋白在蛋糕和灌肠中的最佳添加质量分数分别为3%和2%。

三酶法制备罗非鱼鱼皮胶原蛋白抗氧化肽及活性研究

为了探索制备罗非鱼鱼皮胶原蛋白抗氧化肽的最佳工艺,在碱性蛋白酶和胰蛋白酶酶解的基础上,以酶解温度、酶解时间、酶解pH值和酶与底物质量比([E]/[S])为试验因素,以水解度和DPPH自由基清除率为响应值,采用响应面分析法优化Orientase 20A酶的酶解条件。结果表明:最优工艺参数为:酶解温度为41.74℃、pH3.97、酶解时间为6h、[E]/[S]为1.5%,酶解液水解度和DPPH自由基清除率的预测值分别为9.42%和35.01%,验证值分别为9.57%和35.21%。响应面对酶解法制备罗非鱼鱼皮胶原蛋白抗氧化肽的酶解条件的优化是可行的,可以用于实际预测。抗氧化活性实验表明,酶解肽具有较强的清除DPPH自由基和ABTS+.能力,其IC50值分别为10.78mg/mL和8.26mg/mL。

胶原、明胶和水解胶原蛋白的护肤功能比较

通过乌氏黏度法测定胶原、明胶和水解胶原蛋白的相对黏度和特性黏数,三硝基苯磺酸(TNBS)法测定样品的自由氨基质量摩尔浓度,在不同相对湿度环境下测定样品的吸湿性和保湿性,荧光标记样品方法观察它们在大白鼠皮肤表层的分布和渗透情况以及角质形成细胞培养实验评价3种样品的生物活性,研究了3种样品的物理化学性能和护肤功能差异。结果表明:胶原的相对黏度是明胶和水解胶原蛋白的5倍左右,其特性黏数也明显大于明胶和水解胶原蛋白;胶原的自由氨基质量摩尔浓度最小,其次是明胶,水解胶原蛋白最大;胶原的吸湿性优于明胶和水解胶原蛋白;胶原、明胶和水解胶原蛋白都能渗透至毛囊中,但只有胶原仍均匀分布于皮肤表面,显示其优良的保湿功能;只有胶原能明显促进细胞的生长和繁殖,而在明胶和水解胶原蛋白上培养的角质形成细胞的生长情况与参比样相似。因此,胶原比明胶和水解胶原蛋白具有更优良的吸湿、保湿性能以及抗皮肤衰老功效。

蛋白鞣剂的研制与应用

本文对铬革屑水解后的残渣———铬泥的利用进行了研究。采用碱水解和酶水解的方法将铬泥进一步水解提取胶原蛋白 ,用甲醛对胶原蛋白进行改性制备蛋白鞣剂回用于制革生产中。实验结果表明 ,用 1 2 %的甲醛(以胶原重计 )改性得到的蛋白鞣剂用于猪皮鞣制 ,坯革收缩温度可达85℃ ,其填充性能好 ,且革坯色白 。

酶法提取牛皮胶原蛋白的研究

以牛皮制革废弃物—碱皮边角为原料 ,用木瓜蛋白酶水解提取胶原蛋白 ,对影响酶水解过程的各个因素进行了试验 ,找出了较好的水解条件 ;分析了水解液蛋白质浓度、氨基酸浓度等。