蚕丝蛋白水解工艺及作为化妆品添加剂的应用研究

蚕丝蛋白是一种新型化妆品添加剂,含有多种氨基酸和蛋白质,无毒、副作用,具有很广泛的应用价值。研究了蚕丝水解液的制备工艺及水解过程中pH、温度、反应时间对水解程度的影响。结果表明,pH越高,蚕丝蛋白水解程度越大,收率越高。较高的温度可使蚕丝蛋白水解速度加快,但水解液颜色较深,较低的温度,水解速度较慢。反应时间越长,蚕丝蛋白水解程度越大。并介绍蚕丝水解液在化妆品中的添加方法及如何解决试验过程中存在的实际问题。     

几种常用蛋白胨的氨基酸含量分析

采用日立 835型氨基酸组分分析仪测定了生物制品培养基常用蛋白胨的氨基酸含量 ,结果表明 ,氨基酸总量由高到低依次为厚氏消化液、盐酸水解酪蛋白液、酪蛋白胰酶消化液、黄豆蛋白酶水解液 ;必需氨基酸总量由高到低依次为厚氏消化液、酪蛋白胰酶消化液、盐酸水解酪蛋白液、黄豆蛋白酶水解液     

几种常用蛋白胨的基酸含量分析

采用日立－８３５型氨基酸组分分析仪测定了生物制品培养基常用蛋白胨的氨基酸含量，结果表明，氨基酸总量由高到低依次为厚氏消化液，盐酸水解酪蛋白液、酪蛋白胰酶消化液、黄豆蛋白酶水解液；必需氨基酸总量由高到低次为厚氏消化液、酪蛋白胰蛋消化液、盐酸水解酪蛋白液、黄豆蛋白酶水解液。     

废酵母水解制备复合氨基酸调味液

啤酒废酵母经盐酸水解生成富含复俣氨基酸等多种营养物质的水解液，其最佳水解条件为：９０℃，２０ｈ，浓盐酸与干废平质量之比为２．４：１，盐酸浓度４ｍｏｌ／Ｌ。水解液经精制、调配、灭菌制得复事氨基酸调味液。     

应用AQC柱前衍生荧光检测脑蛋白水解液中的氨基酸

目的 利用AQC柱前衍生荧光对脑蛋白水解液中游离氨基酸进行检测。方法 以6-氨基喹啉基-N-羟基琥珀酰亚胺基-氨基甲酸酯(AQC)为柱前衍生化试剂,利用高压液相色谱荧光检测器系统考察氨基酸衍生和液相分离过程中的各种影响因素,检测脑蛋白水解液中各种游离氨基酸含量。结果 确定氨基酸的浓度在250μmol/L最为合适,准确的测定脑蛋白水解液中氨基酸的种类及含量。结论 采用荧光检测器可以准确地测定蛋白质中氨基酸组成及含量。     

稻秸半纤维素水解条件和水解液脱毒的研究

为了充分利用稻秸半纤维素,并提高水解液发酵性能,对稻秸半纤维素的水解条件和水解液脱毒进行了研究。考察了酸浓度、温度、时间和固液比对稻秸半纤维素水解率的影响;通过正交实验设计确定水解的最优条件为:硫酸质量分数3%,温度120℃,时间1.5h,固液比(W/V)1∶10;在此条件下得到水解液,通过对有机溶剂萃取、大孔树脂吸附和活性炭吸附多种脱毒方法的比较,确定用Ca(OH)2+S-8型树脂进行水解液脱毒。     

茚三酮比色法与甲醛滴定法测定棉籽粕蛋白水解度的比较

本文选用中性蛋白酶水解棉籽粕蛋白,对不同酶解时间的棉籽粕蛋白水解液的水解度分别用茚三酮比色法及甲醛滴定法进行测定。结果表明,与甲醛滴定法相比,茚三酮比色法更简便、更快速,且灵敏度高、可重复性强。是最适合测定低浓度棉籽蛋白水解液水解度的方法。     

化妆品用牛角、牛毛水解液的制备和研究

制备了在不同酸性条件下水牛用、牛毛的水解液。通过水解液氨基酸含量、粘度和水解液中蛋白质平均分子量的测定，研究了水解液性质与酸性条件及水解时间的关系。同时，研究了各种水解液的护发作用。     

动物毛发酸水解工艺和生态环境保护剂的研究

以动物毛发为原料,采用酸水解的方法,对毛发进行水解,通过对水解条件的研究确定的最佳工艺条件为:毛发水解的最佳盐酸浓度为28%~30%,最佳温度为114℃、最佳水解时间为11 h。氨基酸分析结果表明:鸡毛和猪毛水解液均中含有17种氨基酸,这些氨基酸对水体中的有毒有害物质具有很强的吸付与分解能力。此外,本实验初步确定了毛发水解液环境保护剂的生产应用工艺技术参数。     

化妆品天然成分原料介绍(Ⅶ)

正1水解蛋蛋白(Hydrolyzed egg protein)蛋蛋白(Egg protein)是常见的蛋白质。就蛋白质的组成而言,蛋白的蛋白质比较单纯,也容易制取。水解蛋蛋白(Hydrolyzed egg protein)也称作蛋白胨,是白蛋白用酶水解后得到的产物,以八肽及以下寡肽为主的水解液。1.1白蛋白的氨基酸组成(见表1)     

人胎盘血水解液代替人红细胞水解液用作疫苗保护剂的研究

人胎盘血水解液的一般理化指标、氨基酸组成和含量均与人红细胞水解波接近。用其作为麻疹、风疹和腮腺炎疫苗的保护剂，在疫苗冻干前、冻干后及37℃1周后病毒滴度均能达到规程要求。用于制备麻疹和风疹疫苗共200余批，成品病毒滴度和37℃1周后病毒滴度均优于人红细胞水解液，说明人胎盘血水解液完全可以代替人红细胞水解液作为保护剂用于制备麻疹、风疹和腮腺炎疫苗。     

Production and characterization of an extensive rapeseed protein hydrolysate

Rapeseed protein isolate has been used as starting material for the generation of an extensive protein hydrolysate. Protein hydrolysis was produced by using sequentially an endopeptidase (Alcalase) and an exopeptidase (Flavourzyme). The final hydrolysate has a 60% degree of hydrolysis and was completely soluble between pH values 2.5 and 7. Molecular weight profile of the protein hydrolysate was characterized by gel filtration chromatography. A reduction in protein size was observed during the hydrolysis process with accumulation of small peptides and free amino acids after Flavourzyme digestion. Amino acid composition of fractions with different molecular weights of the final hydrolysate was analyzed. Some of these fractions, enriched or poor in certain amino acids, could be used for supplementation or treatment of determined clinical syndromes.     

猪牛鸡肉酶解液中游离氨基酸及呈味特性的对比分析

为对比分析猪肉、牛肉与鸡肉酶解液中游离氨基酸的组成及含量,采用氨基酸自动分析仪分析检测猪肉、牛肉与鸡肉酶解液中的游离氨基酸,通过计算味道强度值(TAV)确定各游离氨基酸对猪肉、牛肉与鸡肉酶解液滋味的贡献率。 结果表明,鸡肉酶解液中鲜味和甜味氨基酸质量分数以及味道强度值均大于猪肉和牛肉酶解液,3种酶解液中味道强度值最大的均为组氨酸,其次为苯丙氨酸,均为呈苦味氨基酸,可见猪、牛、鸡肉酶解液整体滋味以苦味为主。     

In vitro binding capacity of bile acids by defatted corn protein hydrolysate

Defatted corn protein was digested using five different proteases, Alcalase, Trypsin, Neutrase, Protamex and Flavourzyme, in order to produce bile acid binding peptides. Bile acid binding capacity was analyzed in vitro using peptides from different proteases of defatted corn hydrolysate. Some crystalline bile acids like sodium glycocholate, sodium cholate and sodium deoxycholate were individually tested using HPLC to see which enzymes can release more peptides with high bile acid binding capacity. Peptides from Flavourzyme defatted corn hydrolysate exhibited significantly (p < 0.05) stronger bile acid binding capacity than all others hydrolysates tested and all crystalline bile acids tested were highly bound by cholestyramine, a positive control well known as a cholesterol-reducing agent. The bile acid binding capacity of Flavourzyme hydrolysate was almost preserved after gastrointestinal proteases digestion. The molecular weight of Flavourzyme hydrolysate was determined and most of the peptides were found between 500-180 Da. The results showed that Flavourzyme hydrolysate may be used as a potential cholesterol-reducing agent.     

近临界水中鱼蛋白水解及水解液脱色研究

鱼类蛋白包括鱼肉及鱼类加工过程中产生的废弃物,文中采用近临界水技术,在反应温度180—320℃,反应压力5—26 MPa,反应时间5—60 min,无催化剂条件下将其制备成氨基酸,不但能提高附加值,而且有利于环境保护。实验结果发现,水解物含17种氨基酸,水解物中不同种类氨基酸的产率随反应温度、反应压力和反应时间的变化规律各不相同。对其中8种含量高、用途广、附加值高的氨基酸,分别得到了最佳水解工艺。以颗粒状活性炭为脱色剂,对水解液在不同pH值、活性炭用量、吸附温度和吸附时间条件下进行脱色实验,并考察脱色率和氨基酸损失率,结果表明,较好的脱色工艺条件为:pH=4.0,活性炭用量为0.020 g/mL,吸附温度45℃,吸附时间25 min,脱色率90%。被活性炭吸附的氨基酸,可以通过解吸附得到回收。     

Preparation and nutritional characteristics of a hydrolysate from pepitona (Arca zebra)

Two soluble products resulting from the hydrolysis of pepitona (Arca zebra) were prepared as flour. Papain at its optimum hydrolysis conditions, previously established, was the enzyme used (40 degrees C for two hours at a pH of 7 in the proportion of 0.3% weight/enzyme/100 g meat). The hydrolysate obtained was then subjected to two different dehydration techniques: drum drying at 121 degrees C and 18 seconds retention, and spray drying at 101 degrees C and 40 psi pressure. The products were then stored for a five-month period at a temperature of 25 degrees C +/- 2 degrees C, time during which chemical determinations were performed in both hydrolysates. Findings showed that the time of storage does exert a significant effect of deterioration on the products. The greater and more significant quality losses occur during the first two months. The dehydration techniques used also affect significantly the soluble nitrogen content, and non-protein nitrogen and soluble solids content, as well as color of pepitona hydrolysates. Spray-drying dehydration technique does not have a significant deteriorating effect. Biological studies undertaken demonstrated that the quality of both hydrolysates is satisfactory from the nutritional and amino acid composition points of view. A protein efficiency ratio (PER) of 2.27 and 2.29 was determined for the hydrolysate dehydrated by drum drier and for the dehydrated by spray drier, respectively. With regard to amino acid composition, both had satisfactory levels of essential amino acids, with a lysine content of 6.9 g/100 g protein for the hydrolysate dehydrated by drum drying, and 8.6 g/100 g protein for the other hydrolysate dehydrated by spray drying.     

Effect of Peptide Size on Antioxidant Properties of African Yam Bean Seed (Sphenostylis stenocarpa) Protein Hydrolysate Fractions

Enzymatic hydrolysate of African yam bean seed protein isolate was prepared by treatment with alcalase. The hydrolysate was further fractionated into peptide sizes of <1, 1-3, 3-5 and 5-10 kDa using membrane ultrafiltration. The protein hydrolysate (APH) and its membrane ultrafiltration fractions were assayed for in vitro antioxidant activities. The <1 kDa peptides exhibited significantly better (p < 0.05) ferric reducing power, diphenyl-1-picryhydradzyl (DPPH) and hydroxyl radical scavenging activities when compared to peptide fractions of higher molecular weights. The high activity of <1 kDa peptides in these antioxidant assay systems may be related to the high levels of total hydrophobic and aromatic amino acids. In comparison to glutathione (GSH), the APH and its membrane fractions had significantly higher (p < 0.05) ability to chelate metal ions. In contrast, GSH had significantly greater (p < 0.05) ferric reducing power and free radical scavenging activities than APH and its membrane fractions. The APH and its membrane fractions effectively inhibited lipid peroxidation, results that were concentration dependent. The activity of APH and its membrane fractions against linoleic acid oxidation was higher when compared to that of GSH but lower than that of butylated hydroxyl toluene (BHT). The results show potential use of APH and its membrane fractions as antioxidants in the management of oxidative stress-related metabolic disorders and in the prevention of lipid oxidation in food products.     

Separation and identification of amino acids from lignite humic acids by thin layer chromatography

Thin layer chromatography with and without temperature gradient was used to identify ten amino acids in the humic acid hydrolysate of Rovinari lignite, using cellulose and volcanic tuff as stationary phases. The acids found were L-leucine, isoleucine, phenylalanine, L-valine, tyrosine, proline, L-alanine, glutamic acid, threonine and L-lysine.     

Sunflower protein hydrolysates for dietary treatment of patients with liver failure

A method is described to obtain hydrolysates with defined characteristics and a high Fischer ratio for patients with liver failure, using sunflower proteins (globulin fraction-II) as starting material. Protein with a branched chain amino acid (BCAA) concentration of 29.7±1.7% is treated in a first step with immobilized chymotrypsin (raw hydrolysate-1). Subsequent ultrafiltration (cut-off 3 kDa) of the hydrolysate gives sunflower protein hydrolysate-I (SFPH-I). In a second step, SFPH-I is treated with immobilized carboxypeptidase-A at alkaline pH for quasi-selective removal of aromatic amino acids (AAA). This sequential two-step process, followed by size exclusion chromatography on a Sephadex G-15 column, yields a product (SFPH-II) with a BCAA concentration of 37.4±2.2% and an AAA concentration of 0.5±0.1%, which gives a very high Fischer ratio (≈75). The product, comprising mainly peptides with molecular weights in the range of 3500 to 750 Da and free amino acids, is hypoallergenic and shows no or only a trace of bitterness. Any bitterness can be completely removed by treatment with Flavozyme^®, giving a hydrolysate that is composed mainly by tri- and dipeptides and free amino acids, and is termed highly hydrolyzed protein hydrolysate (HHPH). Both SFPH-II and HHPH can be used in enteral, parenteral, and oral nutrition for the treatment of patients with liver failure. This product presents all the conditions required for use in the treatment of patients with liver failure: high content in BCAA and low content in AAA, below 2%, and consequently, a very high Fischer ratio, ≈75.     

近临界水中低值鱼肉水解制备氨基酸工艺研究

研究了近临界水中低值鱼肉水解制备氨基酸的生产工艺.反应器容积为200 mL,反应温度为180～32℃,反应压力为5～26 MPa,反应时间为5～60 min.利用氨基酸分析仪对水解产物中的氨基酸进行定性和定量分析,实验结果发现,实验所用低值鱼肉水解后可得到17种氨基酸.反应温度、反应压力和反应时间对低值鱼肉近临界水解有影响,其中反应温度影响最大,水解产物中不同种类氨基酸的产率随反应温度、反应压力和反应时间的变化规律各不相同.分别对其中8种含量较高、用途较广、附加值较高的氨基酸,进行了反应温度、反应压力、反应时间对水解液中氨基酸浓度影响的实验,得到了在较低的反应温度、合适的反应压力和一定的反应时间内获得较高氨基酸产率的水解工艺.分别采用空气、氮气和二氧化碳作为反应气氛,进行水解实验,结果表明,对亮氨酸、组氨酸和异亮氨酸,应该采用氮气或二氧化碳反应气氛,对其他氨基酸可以采用空气作为反应气氛.