Effects of high-pressure-modified soy 11S globulin on the gel properties and water-holding capacity of pork batter

The effects of high-pressure-modified soy 11S globulin (0.1, 200, and 400 MPa) on the gel properties, water-holding capacity, and water mobility of pork batter were investigated. The high-pressure-modified soy 11S globulin significantly increased (P < 0.05) the emulsion stability, cooking yield, hardness, springiness, chewiness, resilience, cohesiveness, the a^* and b^* values, and the G′ and G′′ values of pork batter at 80 °C, compared with those of 0.1 MPa-modified globulin. In contrast, the centrifugal loss and initial relaxation time of T_2b, T₂₁, and T₂₂ significantly decreased (P < 0.05). Meanwhile, the microstructure was denser, and the voids were smaller and more uniform compared with those of 0.1 MPa-modified globulin. In addition, the sample with 11S globulin modified at 400 MPa had the best water-holding capacity, gel structure, and gel properties among the samples. Overall, the use of high-pressure-modified soy 11S globulin improved the gel properties and water-holding capacity of pork batter, especially under 400 MPa.     

Solubility of amaranth seed proteins in sodium sulphate and sodium chloride: the main factor in quantitative extraction for analysis

Nitrogen was extracted more efficiently from amaranth seed with 0.04 M Na₂SO₄ (5% w/v) than with either 0.09 M or 0.17 M NaCl (5% or 10% w/v), despite both solutions having the same ionic strength (μ= 1). Solubility of saline soluble proteins (albumin ± globulin) was very poor in either water or 1M NaCl, but increased in 0.4M NaCl at alkaline pH between 7 and 10. Globulins were very soluble in 0.4M NaCl at a pH 9. Albumin was the main storage protein. Saline soluble proteins formed very weak gels.     

豫豆-25 11S球蛋白凝胶性的研究Ⅱ.加热时间和中性盐的影响

研究了加热时间和中性盐对豫豆 2511S球蛋白凝胶质构特性的影响.结果表明:随着加热时间的延长,凝胶的硬度、脆度、粘性增加,但30min后增加趋势不明显,豫豆 2511S球蛋白要形成成熟的、质构性能优良的凝胶,加热时间以大于30min为宜;NaCl对酸性凝胶与碱性凝胶的影响有很大的差异.     

Isolation,purification, and characterization of the globulin from wheat germ

This research optimized the extraction and purification of globulin from wheat germ and assessed the molecular weight distribution and structure properties of the globulin obtained. The results showed that the relative extraction efficiency and purity of wheat germ globulin (WGG) reached 18.0% and 89.1% under the enzymolysis conditions of 0.32‰ α-amylase, pH 6.5, and 55 °C. The maximal precipitation rate of WGG (91.3%) was obtained with pH 4.3 (acid precipitation). Additionally, the molecular weight of WGG was mainly distributed below 70 kDa. FT-IR confirmed that random coils (30.95%), β-sheet (27.02%), α-helix (26.55%), and β-turn (15.48%) were the secondary structures of WGG. Furthermore, LTQ mass spectrometry showed that WGG was rich in variety and high in complexity, which retrieved 1274 proteins belonging to 392 proteomes by inverse peptide analysis. The findings endow a great potential of preparing WGG with superior functionality for food applications.     

SSR标记辅助回交转育大豆7S球蛋白α-亚基致敏蛋白缺失新品系

为快速培育7S球蛋白致敏蛋白α-亚基缺失的优质大豆新品系,以（α＇＋α）-亚基双缺失型材料日B为供体亲本,东农47为受体亲本,以杂交一回交转育方法为基础,结合SSR标记辅助遗传背景选择与主要农艺性状鉴定及品质分析,在BC2F4选育到7S球蛋白α-亚基缺失新品系Cb80。Cb80综合农艺性状优良,遗传背景回复率大于90％,其蛋白质及氨基酸总量为44．1％、41．95％,分别比轮回亲本东农47提高3．5和3．76个百分点。     

大豆7S和11S球蛋白的结构和功能性质

主要介绍大豆７Ｓ和１１Ｓ球蛋白的结构和功能性质，大豆蛋白质各个成分的分子量有所不同，按超速离心分离系数可分为２Ｓ，７Ｓ１１Ｓ和１５Ｓ４个组份。７Ｓ组份占总蛋白质的３０．９％，它是由４种不同大豆蛋白民组成，１１Ｓ组份占总大豆蛋白质的４１％，而且都是单一的１１Ｓ球蛋白，１１Ｓ球蛋白的等电点为ｐＨ４．６４。     

11S球蛋白酶解产物功能特性及对猪肉肠品质的影响研究

以中豆36为原料,提取11S球蛋白,用胰蛋白酶进行水解。研究不同水解度酶解产物的乳化性、持水性、持油性等功能特性,比较不同水解度产物添加到猪肉肠中对其质构及得率等的影响。结果表明水解度为12%时,11S球蛋白酶解产物的乳化活性及乳化稳定性最高并且对肉肠质构特性和得率影响最佳。     

椰子分级蛋白制备的研究

通过改良的Osboren法对脱脂椰子粉进行分级提取,得到清蛋白、球蛋白、醇溶蛋白和谷蛋白,并对4种椰子蛋白进行氨基酸组成分析和SDS-PAGE电泳分析。在单因素实验基础上,利用正交实验对4种椰子蛋白提取条件进行优化。结果表明,4种椰子蛋白最佳提取工艺条件为:在液料比10∶1、提取时间4 h、提取温度50℃条件下,清蛋白提取率为49. 05%,纯度为57. 1%;在液料比10∶1、提取时间4 h、提取温度50℃条件下,球蛋白提取率为46. 65%,纯度为70. 8%;在液料比10∶1、提取时间5 h、提取温度55℃、乙醇体积分数75%条件下,醇溶蛋白提取率为18. 01%,纯度为32. 7%;在液料比10∶1、提取时间4 h、提取温度50℃、碱溶p H 10. 0条件下,谷蛋白提取率为26. 78%,纯度为70. 4%。椰子清蛋白、球蛋白和谷蛋白中谷氨酸、精氨酸和天冬氨酸的含量明显高于其他氨基酸。除了清蛋白有2条谱带相对分子质量较大,其他3种椰子蛋白相对分子质量都相对较小,整体来说椰子蛋白是一种较为优质的蛋白质。     

Activities and sequences of the angiotensin I‐converting enzyme (ACE) inhibitory peptides obtained from the digested lentil (Lens culinaris) globulins

The aim of this study was the identification of potentially bioaccessible ACE‐inhibitory peptides obtained by in vitro gastrointestinal digestion of lentil globulins. ACE‐inhibitory peptides were purified by ion exchange chromatography and gel filtration. After the first step of purification, three peptide fractions with potential antihypertensive properties were obtained and the highest inhibitory activity was determined for the fraction 5 (IC₅₀ = 0.02 mg mL^?1). This fraction was separated on Sephadex G10, and six peptide fractions were obtained. The peptides of fraction (5‐F) with the highest potential antihypertensive activity (IC₅₀ = 0.13 mg mL^?1) were identified using ESI‐MS/MS. The sequences of peptides were KLRT, TLHGMV and VNRLM. Based on Lineweaver–Burk plots for the fraction 5‐F, the kinetic parameters as K_m (1.24 mm ), V_max (0.012 U min^?1), K_i (0.12 mg mL^?1) and mode of inhibition were determined.     

Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish

Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely based on correlations between biomarker endpoints (e.g., biochemical processes related to the immune and endocrine system, pathological changes in tissues and reproduction and development) and tissue residue levels of OHCs (e.g., PCBs, DDTs, CHLs, PBDEs and in a few cases perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonates (PFSAs)). Some exceptions include semi-field studies on comparative contaminant effects of control and exposed cohorts of captive Greenland sled dogs, and performance studies mimicking environmentally relevant PCB concentrations in Arctic charr. Recent tissue concentrations in several arctic marine mammal species and populations exceed a general threshold level of concern of 1 part-per-million (ppm), but a clear evidence of a POP/OHC-related stress in these populations remains to be confirmed. There remains minimal evidence that OHCs are having widespread effects on the health of Arctic organisms, with the possible exception of East Greenland and Svalbard polar bears and Svalbard glaucous gulls. However, the true (if any real) effects of POPs in Arctic wildlife have to be put into the context of other environmental, ecological and physiological stressors (both anthropogenic and natural) that render an overall complex picture. For instance, seasonal changes in food intake and corresponding cycles of fattening and emaciation seen in Arctic animals can modify contaminant tissue distribution and toxicokinetics (contaminant deposition, metabolism and depuration). Also, other factors, including impact of climate change (seasonal ice and temperature changes, and connection to food web changes, nutrition, etc. in exposed biota), disease, species invasion and the connection to disease resistance will impact toxicant exposure. Overall, further research and better understanding of POP/OHC impact on animal performance in Arctic biota are recommended. Regardless, it could be argued that Arctic wildlife and fish at the highest potential risk of POP/OHC exposure and mediated effects are East Greenland, Svalbard and (West and South) Hudson Bay polar bears, Alaskan and Northern Norway killer whales, several species of gulls and other seabirds from the Svalbard area, Northern Norway, East Greenland, the Kara Sea and/or the Canadian central high Arctic, East Greenland ringed seal and a few populations of Arctic charr and Greenland shark.