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1.
Jing-jie Xie Xiao-Li Zou Yan-ping Li Zhuang-Li Kang Han-jun Ma 《International Journal of Food Science & Technology》2022,57(4):2459-2466
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 T2b, 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. 相似文献
2.
Xiao-Mei Sha Li-Jun Zhang Wen-Mei Chen Guang-Yao Wang Jin-Lin Li Zi-Zi Hu Zong-Cai Tu 《International Journal of Food Science & Technology》2022,57(3):1573-1586
Thermal action in extraction process had effects on characteristic tryptic peptides identification and gelling properties of porcine gelatin. SDS-PAGE, HPLC-LTQ/Orbitrap high-resolution mass spectrometry, texture analyser and rheometer were used to evaluate collagen depolymerisation degree, characteristic tryptic peptides and gelling properties of gelatins prepared in various thermal actions. Results showed that with increasing temperature and time, depolymerisation degree enlarged, while gel strength, gelling and melting temperature decreased. Mass spectra showed that 47 and 49 common characteristic tryptic peptides were identified in gelatins extracted at 50 °C and 100 °C with various times, respectively. Moreover, 34 common characteristic tryptic peptides were identified in all gelatin samples. Further comparison between this work and our previous investigations yielded 20 common characteristic tryptic peptides, which stably exist in various thermal actions. These common characteristic tryptic peptides may be very helpful for the accurate authentication of porcine gelatin. 相似文献
3.
Corey Andrews Yiting Xu Michael Kirberger Jenny J. Yang 《International journal of molecular sciences》2021,22(1)
Calmodulin (CaM) is an important intracellular protein that binds Ca2+ and functions as a critical second messenger involved in numerous biological activities through extensive interactions with proteins and peptides. CaM’s ability to adapt to binding targets with different structures is related to the flexible central helix separating the N- and C-terminal lobes, which allows for conformational changes between extended and collapsed forms of the protein. CaM-binding targets are most often identified using prediction algorithms that utilize sequence and structural data to predict regions of peptides and proteins that can interact with CaM. In this review, we provide an overview of different CaM-binding proteins, the motifs through which they interact with CaM, and shared properties that make them good binding partners for CaM. Additionally, we discuss the historical and current methods for predicting CaM binding, and the similarities and differences between these methods and their relative success at prediction. As new CaM-binding proteins are identified and classified, we will gain a broader understanding of the biological processes regulated through changes in Ca2+ concentration through interactions with CaM. 相似文献
4.
The molecular design of short peptides to achieve a tailor-made functional architecture has attracted attention during the past decade but remains challenging as a result of insufficient understanding of the relationship between peptide sequence and assembled supramolecular structures. We report a hybrid-resolution model to computationally explore the sequence–structure relationship of self-assembly for tripeptides containing only phenylalanine and isoleucine. We found that all these tripeptides have a tendency to assemble into nanofibers composed of laterally associated filaments. Molecular arrangements within the assemblies are diverse and vary depending on the sequences. This structural diversity originates from (1) distinct conformations of peptide building blocks that lead to different surface geometries of the filaments and (2) unique sidechain arrangements at the filament interfaces for each sequence. Many conformations are available for tripeptides in solution, but only an extended β-strand and another resembling a right-handed turn are observed in assemblies. It was found that the sequence dependence of these conformations and the packing of resulting filaments are determined by multiple competing noncovalent forces, with hydrophobic interactions involving Phe being particularly important. The sequence pattern for each type of assembly conformation and packing has been identified. These results highlight the importance of the interplay between conformation, molecular packing, and sequences for determining detailed nanostructures of peptides and provide a detailed insight to support a more precise design of peptide-based nanomaterials. 相似文献
5.
建立了一种快速、高效的QuEChERS-高效液相色谱-质谱联用法(QuEChERS-HPLC-MS/MS)测定谷类杂粮制品中脱氧雪腐镰刀菌烯醇(DON)、3-乙酰脱氧雪腐镰刀菌烯醇(3-ADON)、15-乙酰脱氧雪腐镰刀菌烯醇(15-ADON)和玉米赤霉烯酮(ZON)共4种真菌毒素。样品前处理采用乙腈-水溶剂提取,经Florisil+C18+无水硫酸镁净化后检测。以0.10%甲酸-乙腈作为流动相,在质谱检测器的多反应监测模式下进行分析。结果表明,4种真菌毒素在各自的线性范围内线性关系良好,相关系数R2均大于0.999,回收率在85.1%~102.0%,相对标准偏差(RSD)为2.11%~6.22%。该方法具有前处理简单、净化效果好、灵敏度高和检测速度快的优点,适用于谷类杂粮制品中DON、3-ADON、15-ADON 和ZON的分析和定量检测。 相似文献
6.
N_2S_2或N_3S型配体的合成、~(99)Tc~m标记及生物分布研究 总被引:3,自引:2,他引:1
以MAG3为基本分子骨架,根据构效关系,分别引入合适的天然氨基酸,设计合成了4种N2S2或N3S型小分子多肽新配体,并通过了IR,^1H NMR,^13C NMR,MS谱学鉴定和元素分析表征。采用葡庚糖酸钙(GH)交换法对4个配体进行了^99Tc^m标记,研究了配合物在小鼠体内的生物分布特征。结果表明,^99Tc^m-MVGG肾摄取较高,滞留时间较长,血清除快,且肾与其它组织的活度比值高,具备成为肾功能显像剂的条件;^99Tc^m-MPGG肾初始摄取较高,R(肾/血)活度比值高,但肾清除较快,R(肾/肝)活度比值较低;^99Tc^m-MVTC和^99Tc^m-MPTC心肌初始摄取均较高,但在心肌和血中的清除速度较快。 相似文献
7.
对KCl与NaCl在低盐固态酱油发酵中的应用进行了比较研究。结果表明:用KCl代替NaCl,KCl的浓度要高于NaCl才能抑制发酵期间杂茵的污染,且使用KCl的发酵效果比NaCl要好。 相似文献
8.
9.
目的制备新生牛肝活性肽并评价其安全性。方法采用膜法分离制备新生牛肝活性肽。将3批制品于37~40℃,75%相对湿度条件下存放3个月,以多肽含量为指标观察其稳定性,并进行急性毒性试验、小鼠骨髓细胞微核试验、Ames试验、小鼠精子畸形试验和大鼠喂养试验。结果制备的3批新生牛肝活性肽存放3个月后,多肽含量无明显下降,质量稳定。小鼠和大鼠经口灌人大于20.0g/kg体重的新生牛肝活性肽,均无急性毒性。3种致突变试验均未显示出致突变性,大鼠喂养试验各项指标均未见明显毒性。结论新生牛肝活性肽未表现出明显毒性。 相似文献
10.
An endoprotease was purified from melon fruit (Cucumis melo L.) by ammonium sulfate precipitation, gel filtration and ion-exchange chromatography using t-butyloxycarbonyl-Ala-Ala-Pro-Leu p-nitroanilide as a substrate. The molecular weight was estimated as 26,000 and isoelectric point pH 9.5. It preferentially hydrolyzed peptide bonds of the carboxyl terminal sides of Leu, Ala, His, Gin, and Am. Activity was strongly inhibited by diisopropyl phosphofluoridate, indicating the serine protease nature of the enzyme. The migration distance on electrophoresis, molecular weight and substrate specificity differed from cucumisin, a known protease from melon. This unusual protease may have potential for special food treatment applications. 相似文献