Prevention of breast cancer by dietary polyphenols—role of cancer stem cells

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.     

紫苏油的药理活性及其缓释技术研究进展

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。     

Impact of cryoconcentration on casein micelle size distribution,micelles inter-distance,and flow behavior of skim milk during refrigerated storage

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).     

Comparative studies of quality changes in white and dark muscles from common carp (Cyprinus carpio) during refrigerated (4 °C) storage

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 (P < 0.05) differences in tyramine and cadaverine content. Although dark muscle was significantly (P < 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.     

Quercetagetin loaded in soy protein isolate–κ-carrageenan complex: Fabrication mechanism and protective effect

In the present study, the potential of soy protein isolate (SPI)–κ-carrageenan (κ-CG) complex as a protective carrier for quercetagetin was investigated at different pH values (pH 2.3 and 6.5). The particle size of the ternary aggregates was slightly increased at pH 2.3, yet dramatically decreased at pH 6.5 with increasing quercetagetin concentration. Moreover, the negative ζ-potential of the ternary aggregates was increased significantly (p < 0.05) at pH 6.5. The addition of quercetagetin to the SPI–κ-CG complex could highly quench the intrinsic fluorescence of SPI. Circular dichroism spectra further suggested that the bound quercetagetin could induce the rise of β-sheet and β-turn contents at the cost of α-helix and unordered coil fractions of SPI. In addition, quercetagetin could increase the viscoelasticity of the ternary aggregates at both pH. Furthermore, the SPI–κ-CG complex was found to be superior to single SPI or κ-CG in terms of improving light stability and radical scavenging ability of quercetagetin.     

Antimicrobial effects of cinnamon bark oil on microbial composition and quality of grass carp (Ctenopharyngodon idellus) fillets during chilled storage

In this study, 11 essential oils were initially screened for antimicrobial activity against Aeromonas veronii, Acinetobacter johnsonii, Shewanella putrefaciens, and Pseudomonas jessenii. Cinnamon bark oil exhibited the highest antimicrobial activity and was used as a natural preservative in grass carp fillets stored at 4 ± 1 °C. Sensory assessment, total volatile basic nitrogen (TVB-N), color, biogenic amines, adenosine triphosphate (ATP)-related compounds, K-value, and presence of microbiota were analyzed during storage. Cinnamon bark oil treatment was found to be effective in enhancing organoleptic quality, inhibiting microbial growth, and delaying the increase of TVB-N, putrescine, cadaverine and K-value. Based on sensory analysis, shelf-life of grass carp fillets was 8 days for the control and 12 days for the treatment group. According to high-throughput sequencing, Aeromonas and Pseudomonas were the predominant microbiota in fresh grass carp. As storage time progressed, the microbial composition of both control and treatment samples became less diverse. Pseudomonas followed by Aeromonas were dominant in spoiled control samples. However, there were significant differences in microbial composition between control and treatment samples at the end of storage. Cinnamon bark oil treatment inhibited the growth of Aeromonas and Shewanella, and Pseudomonas was the only predominant microbiota found in spoiled treatment samples.     

Effects of plant-based content,flavor and texture information on consumer satisfaction with non-fried ramen

The purpose of this study was to screen flavor information for positioning of non-fried ramen products and to examine the applicability of plant-based ingredient content in flavor communication. Effects of information related to savoriness, spiciness, menu name, plant-based ingredient content (%), and texture of samples on informed satisfaction were examined using home–use tests and online surveys. In order to form a regression model that explained variations in the informed satisfaction of non-fried ramen samples, we created indices that integrated the importance of information and the congruence of information with flavor perception. We have confirmed that effects of congruence on increasing satisfaction were higher than those of importance of information. When congruence/importance was used as an independent variable, a quadratic regression equation has explained the variations on satisfaction levels with an R² value of 72.7% (p = 0.006). Considering the positive congruence effect that plant-based ingredient percentages and perceived flavors had on informed satisfaction levels, communication schemes are needed to promote foods that have high percentages of plant-based ingredients.     

Proteomic characterisation of heat-induced hydrolysis of sodium caseinate

The hydrolysis of sodium caseinate during heating for up to 120 min at pH 7.0 and 130 °C was investigated. The formation of 2% trichloroacetic acid (TCA)-soluble peptides was studied using spectrofluorimetry and high resolution liquid chromatography-mass spectrometry (LC-MS), whereas sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to study hydrolysis of the caseins. LC-MS and spectrofluorimetry showed an increase in 2% TCA-soluble peptides over time, confirming that proteolysis had occurred, whereas SDS-PAGE showed a decrease in band intensity for the main caseins over time. In total, 1023 casein-derived peptides were identified. For eleven of the most abundant peptides, release and breakdown were modelled. Peptide bonds containing Pro, Ser, Asn and/or Asp were preferentially hydrolysed during heating. The production of peptides in this manner may represent a novel alternative to enzymatic hydrolysis strategies.     

Single- and multi-cycle high hydrostatic pressure treatment on microbiological quality of mud snail (Bullacta exarata) during refrigerated storage

High hydrostatic pressure (HHP) processing is an industrial technology used for preservation of a wide range of food products, and vacumm-packed mud snails (Bullacta exarata) were HHP processed to ensure food safety and shelf-life stability. The effects of single- and multi-cycle HHP treatment, especially the combination of different intensities, on the microbial behavior and shelf-life extension of B. exarata during subsequent storage were investigated. Total microbial count, psychrophilic microorganisms, Clostridium bacteria, total Enterobacteriaceae and H₂S-producing bacteria were enumerated during subsequent refrigerated storage, and Gompertz model was chosen to predict the shelf-life, growth rate, lag time and generation time. The results showed that the initial microbial load was obviously reduced as the pressure increased. Total Enterobacteriaceae and H₂S-producing bacteria were not detected in multi-cycle HHP processing during refrigerated storage. Moreover, multi-cycle HHP method (B + F) could improve the shelf-life of B. exarata for more than 38 days. The model indicated that the lag time for Clostridium bacteria processed with multi-cycle HHP (B + F) was extended to 24.65 days. Our findings will be of aid for the establishment of general process guidelines, and demonstrated that multi-cycle HHP technology has potential for application in mud snail preservation and processing.