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91.
Khanh Dang VuHélène Carlettini Janie BouvetJacinthe Côté Gilles DoyonJean-François Sylvain Monique Lacroix 《Food chemistry》2012,132(2):959-967
The effect of cranberry extracts and juices during cranberry juice processing on the antiproliferative properties against colon cancer cells was investigated. Two colon cancer cell lines HT-29 and LS-513 were treated with different concentrations of cranberry phenolic extracts from fruits, puree, depectinised puree and pomace and different concentration of three juices (raw, filtered and concentrated juices). The phenolic extracts consisted of water-soluble phenolic compounds, apolar phenolic compounds and anthocyanins. These phenolic extracts and juices were tested against two cell lines at pH 2.5 (natural juice pH) and at pH 7.0 (physiological pH). All cranberry extracts and juices could inhibit the growth of both cell lines with the IC50 values (the concentration of phenolic content required to inhibit 50% the growth of cancer cells) varied from 3.8 to 179.2 μg gallic acid equivalent/ml. It was found that three types of extracts from fruit at pH 7.0 were the most effective at inhibiting the growth of HT-29 cell line. Extracts containing anthocyanins from fruit and from pomace were the most and the least efficient, respectively, in inhibiting the growth of both cancer cell lines. Further, three juices at natural pH (pH 2.5) were more effective at inhibiting the growth of two cell lines as compared to juices at pH 7.0. Concentrated juice at both pH values was the most effective at growth inhibition of two cancer cell lines compared to two other juices. 相似文献
92.
Serafino Teseo Emmanuel Lecoutey Daniel J. C. Kronauer Abraham Hefetz Alain Lenoir Pierre Jaisson Nicolas Châline 《Journal of chemical ecology》2014,40(5):429-438
Although cuticular hydrocarbons (CHCs) have received much attention from biologists because of their important role in insect communication, few studies have addressed the chemical ecology of clonal species of eusocial insects. In this study we investigated whether and how differences in CHCs relate to the genetics and reproductive dynamics of the parthenogenetic ant Cerapachys biroi. We collected individuals of different ages and subcastes from several colonies belonging to four clonal lineages, and analyzed their cuticular chemical signature. CHCs varied according to colonies and clonal lineages in two independent data sets, and correlations were found between genetic and chemical distances between colonies. This supports the results of previous research showing that C. biroi workers discriminate between nestmates and non-nestmates, especially when they belong to different clonal lineages. In C. biroi, the production of individuals of a morphological subcaste specialized in reproduction is inversely proportional to colony-level fertility. As chemical signatures usually correlate with fertility and reproductive activity in social Hymenoptera, we asked whether CHCs could function as fertility-signaling primer pheromones determining larval subcaste fate in C. biroi. Interestingly, and contrary to findings for several other ant species, fertility and reproductive activity showed no correlation with chemical signatures, suggesting the absence of fertility related CHCs. This implies that other cues are responsible for subcaste differentiation in this species. 相似文献
93.
Influence of Storage on Physicochemical and Volatile Features of Enriched and Aromatized Wax Organogels 下载免费PDF全文
Mustafa Öğütcü Emin Yılmaz Onur Güneşer 《Journal of the American Oil Chemists' Society》2015,92(10):1429-1443
In this study, virgin olive oil (VOO) organogels were produced with beeswax (BW) and sunflower wax (SW) and enriched with β‐carotene, vitamin D3 and E as well as aromatized with strawberry, banana, and butter aromas. The physicochemical, thermal, structural, and sensorial properties of the fresh organogel samples were determined. The peroxide values, antioxidant activities, firmness, and volatile compositions of the fresh samples and those stored for 3 months were also determined. The organogels were not only stable, uniform, and homogenous during the storage period but also the added components did not affect the organogel properties. The panel defined three appearance, four texture, three mouthfeel, four aroma, and four flavor terms to describe the organogels sensorially. Moreover, the added aroma (banana, strawberry, and diacetyl‐butter) components of the fresh and stored organogels were quantified by GC/MS‐SPME. In conclusion, these results demonstrated that beeswax and sunflower wax are very suitable to preserve the aromatic characteristics of these types of spreadable products. 相似文献
94.
Melek Akman Makbule Bilge Akbulut Mehmet Burak Güneşer Ayçe Ünverdi Eldeniz 《Journal of Adhesion Science and Technology》2016,30(5):459-467
To evaluate the effect of intracanal medicaments on the push-out bond strength of Biodentine in comparison with DiaRoot BioAggregate (BA) when used as apical plugs. Forty single-rooted teeth were prepared using Peeso reamers. The samples were divided into four groups. The intracanal medicaments were applied to the root canals as follows: Group1: a combination of metronidazole–ciprofloxacin–cefaclor, Group2: a combination of metronidazole–ciprofloxacin, Group3: calcium hydroxide, and Group4: no medication. After 21 days, the medicaments were removed. The apical part of each root was horizontally sectioned into 1-mm thick slices. The samples were divided into two subgroups, and the following materials were placed: Biodentine, DiaRoot-BioAggregate. After 48-h incubation, the push-out bond strength was measured. The data were analyzed by a two-way ANOVA. Biodentine showed a significantly higher mean push-out bond strength value than DiaRoot-BioAggregate (P = 0.00). The medications have an effect on the push-out bond strength of both materials (P = 0.002). Biodentine showed better adhesive performance as an apical plug than DiaRoot-BioAggregate. 相似文献
95.
96.
Dynamic mechanical analysis of the multiple glass transitions of plasticized wheat gluten biopolymer 下载免费PDF全文
Glass transition of thermo‐molded biomaterials made from wheat gluten and its main protein classes is studied by dynamic mechanical analysis (DMA). The materials are plasticized with variable contents of glycerol (30–40 wt %) and water (0–20 wt %). For all materials, three successive relaxation phases are systematically detected. Their positions shift to lower temperature as the plasticizer content of materials increases. Composition in gluten, glycerol and water of each relaxation phase is estimated using the Couchman‐Karasz model. Irrespective of the plasticizer content or composition, the relaxation phases shows rather constant plasticizer volume fractions. The low‐, middle‐, and high relaxation phases include respectively around 30, 60 and 80 vol % of gluten protein. These relaxations are assigned to the segmental motion of the surface amino‐acid side groups, to the collective motion of packed gluten proteins, and to the gain in protein conformational mobility as a 2D network of interacting plasticizer molecules forms. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43254. 相似文献
97.
Roseli de Souza Santos da Costa Flavia da Silva Santos Daniela de Barros Mucci Tânia Vignuda de Souza Fátima Lucia de Carvalho Sardinha Célia Regina Moutinho de Miranda Chaves Maria das Graças Tavares do Carmo 《Lipids》2016,51(12):1363-1373
The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants. 相似文献
98.
The production of linear low‐density polyethylene (LLDPE) yarns for artificial turf is an advanced extrusion process, which relies heavily on the polymer's semicrystalline structure and inherent strengthening mechanisms to obtain the tailored mechanical properties so typical for turf yarns: a combination of strength and resilience. This review aims to bring together all relevant aspects in the structure–materials–processing interaction triangle which is so strongly in evidence in this application, by first summarizing the specific structural origins of the properties of the semicrystalline LLDPE and then discussing how structure evolves during the different steps of the production process, to eventually come to the final product properties of the yarn. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44080. 相似文献
99.
100.
Hélène Vacher 《Planning Perspectives》2019,34(1):91-113
By shedding light on the overseas branch of the Corps des Ponts-et-Chaussées (CPC), this article analyses the scientific and technical contribution of this sub-group of engineers in the post-Second World War era. After introducing the historical background of the early involvement of the CPC in the French colonies, this paper concentrates on the late colonial period. Details of the strong interconnectedness of metropolitan and overseas technical expertise are provided. It is shown that civil engineering practised overseas not only enhanced many technical fields within the traditional preserve of the Corps but also facilitated the rapid expansion of the Corps out of this very preserve. Engineers were prompt in including urban expertise and town planning, rural hydraulic and hydrogeology within their current field of activities. Consequences were highly significant not only for overseas urban and rural milieu, but also for metropolitan territories undergoing post-war redevelopment. The last section of this article shows how the techno-scientific practice acquired overseas was instrumental in the post-colonial years to foster the redeployment of the CPC as a whole in the different fields of civil engineering on an international scale. 相似文献