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1.
Abstract

Breast cancer is a common malignancy with poor prognosis. Cancer cells are heterogeneous and cancer stem cells (CSCs) are primarily responsible for tumor relapse, treatment-resistance and metastasis, so for breast cancer stem cells (BCSCs). Diets are known to be associated with carcinogenesis. Food-derived polyphenols are able to attenuate the formation and virulence of BCSCs, implying that these compounds and their analogs might be promising agents for preventing breast cancer. In the present review, we summarized the origin and surface markers of BCSCs and possible mechanisms responsible for the inhibitory effects of polyphenols on BCSCs. The suppressive effects of common dietary polyphenols against BCSCs, such as curcumin, epigallocatechin gallate (EGCG) and related polyphenolic compounds were further discussed.  相似文献   
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3.
Buffalo milk proteins (casein, co-precipitate or whey protein concentrate) were phosphorylated with phosphorus oxychloride (POCl3) at three different pH values (5.0, 7.0 and 9.0). The solubilities of phosphorylated milk proteins were examined over the pH range 3.0–9.0 in water and ionic (0.1 m NaCl or 10–70 mm Ca2+) systems. The solubilities of buffalo milk proteins decreased at pH 3.0, while there was an increase in the solubilities of casein and co-precipitate near their isoelectric points upon phosphorylation. Solubilities of these phosphorylated milk proteins were pH dependent in 0.1 m NaCl but there was a decrease in their solubilities with increase in calcium ion concentration. This alteration could be due to the shifting of isoionic points of phosphorylated buffalo milk proteins towards acidic pH.  相似文献   
4.
大蒜活性成分阿霍烯的研究概况   总被引:2,自引:0,他引:2  
阿霍烯作为源自于大蒜的一种活性成分,较之蒜素更加稳定且不具有令人难以接受的蒜辣蒜臭气味,具有抗血栓形成,诱导肿瘤细胞调亡及抗菌消炎等特别的生理功效,是一种天然高效的活性成分。本文综述了近年来有关阿霍烯的生理功效,结构组成及形成机制等的研究概况。  相似文献   
5.
紫苏油的药理活性及其缓释技术研究进展   总被引:1,自引:0,他引:1  
紫苏油营养丰富,可抗过敏、抗炎症、抗癌、抗衰老和降血脂等,具有极高的研究价值。然而我国对紫苏油的研究开发刚刚起步,加之紫苏油易氧化,储存稳定性低,极大地限制了其应用。介绍了紫苏油药理活性和缓释技术的国内外研究现状,以促进紫苏油深度开发和广泛利用。  相似文献   
6.
Cryoconcentration combined with a cascade effect was used to concentrate skim milk up to 25.12% total dry matter. Size, shape, and inter-micellar distance of casein micelles were characterized by ZetasizerNano-ZS, transmission electron microscopy, and ImageJ analyses. Flow properties of the cryoconcentrated skim milk were evaluated during 5 weeks of storage under refrigerated condition at 4 °C. Milk color was also evaluated according to the L*, a*, and b* system. The cryoconcentrated skim milk obtained after three cryoconcentration cycles was characterized by a monomodal distribution of its micelles with a tendency to smaller casein micelles. Approximately 60% of the total micellar volume was occupied by the casein micelles with a size of 100–200 nm, less than 18% of the volume with a size of 50–100 nm and only less than 1% was occupied by micelles with a size > 350 nm. This result shows that cryoconcentration changed the distribution of the mean size of the casein micelles to smaller units. No significant difference was observed on the inter-micellar distance. Cryoconcentration significantly improved the color of skim milk by increasing the L* value up to 67 which was similar to that of whole milk. Transition from a Newtonian to a non-Newtonian behavior was observed from the fourth week storage with a slight increase of casein micelle size.Industrial relevanceA concentration procedure of skim milk based on a complete block cryoconcentration technique was proposed. Application of this sub-zero technology permitted the concentration of skim milk total dry matter up to 25%. The casein micelle size was positively affected by moving the major part of the micelles toward the smaller size, whereas the inter-micellar distance was not affected. This new knowledge can be exploited in milk-based products to enhance the product stability. The cryoconcentrated skim milk color was positively affected since its L* value, which represents the milk whiteness, was significantly improved. The flow behavior of the cryoconcentrated milk was of Newtonian type up to 4 weeks of storage at 4 °C. The generated knowledge in this study can be easily used by the milk processing industry in order to make stable milk product with high dry matter content without adding milk powder, which negatively affects the product sensory properties (floury consistency).  相似文献   
7.
杨宇迪  程湛  满媛  李景明 《食品科学》2017,38(20):103-111
将葡萄籽超微粉碎并添到曲奇饼干中,探究其对曲奇饼干香气成分及感官品质的影响。采用气相色谱-质谱联用仪分别检测了普通葡萄籽粉、葡萄籽超微粉及添加超微粉前后曲奇饼干的香气成分,并结合偏最小二乘判别分析法研究葡萄籽超微粉对曲奇饼干香气成分的影响。结果显示,超微粉碎后香气物质的种类虽未发生明显的改变,但香气成分的相对含量显著增加。葡萄籽超微粉添加比例为5%时,烘烤香比较浓郁。当添加比例达到10%时,曲奇饼干整体风味较为复杂,包括苦杏仁味、香蕉味、水果味/青草味、面包味以及坚果味。采用9点享乐法感官品评结果可以看出,葡萄籽的添加可以为饼干带来可感知的变化,添加比例为5%时,香气得分最高。葡萄籽超微粉会给曲奇饼干香气带来积极的影响,添加比例在10%以内均可被消费者接受。  相似文献   
8.
Differences between white and dark muscles from common carp (Cyprinus carpio) in sensory assessment, total viable counts (TVC), total volatile basic nitrogen (TVB‐N), pH, electrical conductivity (EC), biogenic amines (BAs), nucleotide degradation products and colours were investigated under air and vacuum conditions during refrigerated (4 °C) storage. Compared with white muscle, dark muscle had a higher lipid content, but lower crude protein and moisture content. TVC, TVB‐N, pH, and L* value were higher in white muscle, while K value and a* value were higher in dark muscle. Under both conditions, white and dark muscles had significant (< 0.05) differences in tyramine and cadaverine content. Although dark muscle was significantly (< 0.05) lower in ATP content, it had higher rate of IMP degradation and K value increase. Taking sensory and microbial indexes into consideration, dark muscle appeared to have a longer shelf life than white muscle under both conditions.  相似文献   
9.
The influences of different osmotic solution pretreatments (sucrose, glucose and maltose with concentration of 45%) on the volatile compounds, phenolic compounds and other physicochemical parameters in frozen mangoes were studied. Volatile and phenolic compounds were measured using SPME/GC‐MS and HPLC method, respectively. The results revealed that compared with untreated frozen mango, some volatile compounds (e.g. alcohols, aldehydes and some terpenes and esters) increased significantly and there were more compounds identified in osmo‐dehydrofrozen samples. These changes positively affected mango aroma and resulted in higher sensory scores for osmo‐dehydrofrozen samples. In addition, data on phenolic compounds showed that dehydrofrozen samples pretreated in glucose and sucrose had higher ρ‐hydroxybenzoic acid and quercetin contents, respectively, while samples pretreated in maltose showed higher ρ‐coumaric acid and sinapic acid contents compared with untreated frozen samples. The current work indicates that osmo‐dehydrofreezing can improve the retention of phenolic and aromatic compounds in frozen mango.  相似文献   
10.
The effect of chilled, frozen and freeze‐chilled storage on quality of grass carp fillets and soups was evaluated by sensory score, total aerobic counts and biochemical quality. Fish fillets were stored at 4 °C for 6 days (T1), ?40 °C for 12 h and then at ?20 °C for 5 days (T2), ?40 °C for 12 h and then at ?20 °C for 5 days, followed by at 4 °C for 4 days (T3). T1 showed higher sensory score, salt‐soluble protein content, better colour and texture qualities than T2 and T3 within 3 days. All fillets kept good quality based on the acceptable limit of sensory score, total volatile basic nitrogen and total aerobic count during storage time. According to the transportation and retail time, chilled storage is appropriate when it is within 3 days. If it extends for 5 days, freeze‐chilling treatment keeps better quality, but later chilled fillets should be retailed within 4 days.  相似文献   
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