Browsing by Subject "Protein"

Now showing 1 - 5 of 5
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    Determination of Chitin and protein contents during the isolation of Chitin from shrimp waste
    (Wiley, 2006-05-09) Díaz Rojas, Erika I.; Argüelles Monal, Waldo M.; Higuera Ciapara, Inocencio; Hernández, Javier; Lizardi Mendoza, Jaime; Goycoolea Valencia, Francisco Martín; Biología Celular e Histología
    Accurate determination of chitin and protein contents in crustacean biomass and the intermediate products during the industrial isolation of chitin cannot be made directly from the total nitrogen content, unless the appropriate corrections are applied. This method, however, is affected by the presence of other nitrogen-containing chemical species that are formed endogenously or by the action of microorganisms during the handling of the sample. Therefore, an alternative rapid method to estimate the contents of these components can be very useful both in research and in various fields of application. An original method has been developed to address this problem. The method consists of the development of a set of equations based on the stoichiometric contents of nitrogen of chitin and protein whereby the amounts of each component can be estimated from the value of the total nitrogen content, provided the rest of the proximate composition of the sample is accurately known. In order to validate the procedure, a set of model mixtures of pure chitin and protein concentrate in the solid state, both extracted from shrimp head waste, are used. Excellent agreement between the predicted and real values of chitin and protein are obtained (R2=0.98, slope=0.90). When the proposed method is tested in the analysis of real samples obtained from five different processing protocols of pretreatment of raw shrimp head, it is found that in general, the values of protein and chitin contents throughout the various stages of the process vary as expected.
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    Distribution of bile acid receptor TGR5 in the gastrointestinal tract of dogs
    (Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Giaretta, Paula R.; Suchodolski, Jan S.; Blick, Anna K.; Steiner, Joerg M.; Lidbury, Jonathan A.; Rech, Raquel R.
    Takeda-G-protein-receptor-5 (TGR5) is a receptor for bile acids and its expression has been described in a variety of tissues and species. Characterization of TGR5 distribution and function has been investigated in drug discovery for the treatment of metabolic diseases in humans. Because dogs are one of the species used in biomedical research and share some similarities with human gastrointestinal diseases, the objective of this study was to characterize the distribution of TGR5 receptor in the canine species. This study characterizes the distribution of TGR5 receptor in the gastrointestinal tract, liver, gallbladder, and pancreas of 8 dogs. The distribution of TGR5 antigen and mRNA expression was investigated using immunohistochemistry and RNA in situ hybridization, respectively. TGR5 immunolabeling was located in the cell membrane or in the cell membrane and cytoplasm. TGR5 immunolabeling was broadly distributed in macrophages, endothelial cells, ganglion cells, and leiomyocytes throughout all the examined tissues. Epithelial cells from tongue, stomach to rectum, as well as from gallbladder, biliary and pancreatic ducts demonstrated TGR5 immunolabeling. In endocrine cells, TGR5 immunolabeling was observed in intestinal enteroendocrine cells and islets of Langerhans in the pancreas. The hepatocytes had a unique pattern of immunolabeling located on the canalicular surface of the cell membrane. TGR5 mRNA expression was located mainly in the nucleus and the only negative cells throughout all examined tissues were striated muscle from tongue and esophagus, muscularis mucosae, esophageal glands, and hepatic sinusoids. These findings indicate that the bile acid receptor TGR5 is ubiquitously distributed in the canine gastrointestinal tract.
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    Effect of industrial processing on desert truffles (Terfezia claveryi Chatin and Picoa juniperi Vittadini): proximate composition and fatty acids
    (Wiley, Society of Chemical Industry, 2003-05) Murcia Tomás, María Antonia; Martínez Tomé, Magdalena; Vera, Ana; Gutierrez, Almudena; Honrubia, Mario; Jiménez Monreal, Antonia M.; Morte Gómez, María Asunción; Tecnología de Alimentos, Nutrición y Bromatología
    Our objectives were to investigate the proximate composition of two desert truffles (Terfezia claveryi Chatin and Picoa juniperi Vittadini) and to determine the effects of freezing and canning on proximate composition. The moisture content of T claveryi and P juniperi was 730.9 g kg−1 and 637.8 g kg−1 respectively; ash was 42.5 g kg−1 and 82.1 g kg−1 respectively; protein was 159.5 g kg−1 and 225.4 g kg−1 respectively; lipids were 69.5 g kg−1 and 199.4 g kg−1 respectively; fibre was 83.2 g kg−1 and 130.4 g kg−1 respectively; and carbohydrates were 645.5 g kg−1 and 366.6 g kg−1 respectively. The fatty acids composition showed high quantities of linoleic acid 18:2 (45.4% in T claveryi and 53.0% in P juniperi), the rest of the fatty acids in decreasing order were 16:0 > 18:1 > 18:3 > 18 : 0 + 22 : 0 > 20 : 0 + 24 : 0 > 14 : 0 + 22 : 1 > 15 : 0 + 16 : 1 + 17 : 0 + 21 : 0 in T claveryi and 18 : 1 > 16 : 0 > 18 : 0 + 18 : 3 + 16 : 1 + 20 : 0+22:1 > 14:0 + 24:0 > 15:0 + 17:0 + 22:0 in the P juniperi. Little loss of ash, protein and lipids was observed as a result of industrial processing (p < 0.05).
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    Expression of homeodomain protein CDX2 in colorectal adenoma and adenocarcinoma
    (Murcia : F. Hernández, 2008) Bakaris, Sevgi; Cetinkaya, Ali; Ezberci, Fikret; Ekerbicer, Hasan
    CDX2 is a homeobox domain-containing transcription factor that is important in the development and differentiation of the intestine. In this study, we examined CDX2 expression in normal and neoplastic human colon using a newly isolated monoclonal antibody. When compared to the intensity observed in adjacent normal mucosal epithelial cells, strong nuclear staining for CDX2 was observed in 10 (100%) of 10 colonic adenomas, 30 (88.2%) of 34 colorectal adenocarcinomas, including 17(94.47%) of 18 well-or moderately differentiated tumors and 13(81.2%) of 16 high-grade tumors. The percentage of CDX2 immunopositive cells was generally lower in carcinomas than in adenomas (p<0.001) and lower in moderately or poorly differentiated tumors than in well-differentiated tumors (p<0.001). There was an inverse correlation between CDX2 expression and tumor grade, tumor stage and lymph node metastasis (respectively, p<0.001; p<0.05; p<0.001), but this was not associated with age, gender, or tumor location and size. These results indicate that loss of expression of CDX2 protein may play an important role in the tumorigenesis of colorectal cancers. Down-regulation of CDX2 may cause dedifferentiation of gastrointestinal epithelial cells.
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    In vivo and in vitro Digestibility of an Extruded Complete Dog Food Containing Black Soldier Fly (Hermetia illucens) Larvae Meal as Protein Source
    (Frontiers, 2021-06-11) Penazzi, Livio; Schiavone, Achille; Russo, Natalia; Nery, Joana; Valle, Emanuela; Madrid, Josefa; Martínez, Silvia; Hernandez, Fuensanta; Pagani, Elena; Ala, Ugo; Prola, Liviana; Producción Animal; Department of Veterinary Sciences, University of Turin, Grugliasco, Italy; Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
    Growing attention is being directed toward insects as a novel and sustainable source of protein for pet food. The aim of the study was to evaluate nutrient digestibility of a diet containing black soldier fly larvae as its main protein source. Moreover, the purpose of the study was to compare the traditional in vivo total collection method with the in vivo marker method and in vitro digestibility method. Two isonitrogenous and isoenergetic dry diets containing either venison meal (CTRL diet) or black soldier fly larvae meal (BSF diet) as their primary sources of proteins were fed to six adult dogs, according to a Latin square design. The digestibility of nutrients was determined using both in vivo (“total collection” and “internal marker” approaches) and in vitro methods. The two diets showed similar nutrient digestibility values for dry matter, organic matter, ether extract, ash, and phosphorus. However, a statistical trend (p = 0.066) was observed indicating greater protein digestibility in the BSF diet compared with the CTRL diet. Calcium digestibility was higher in the BSF diet compared with the CTRL diet (p = 0.018). On the contrary, fiber digestibility was lower in the insect-based diet compared with the venison diet (p < 0.001). There was no difference between total collection and internal marker methods in the assessment of in vivo digestibility for any of the nutrients considered. The in vitro digestibility values for dry matter, organic matter, and crude protein, as well as the estimated in vivo digestibility of organic matter and crude protein by the means of the predictive equation, were aligned with the in vivo results, although in vitro estimations were consistently higher compared with those obtained by in vivo analysis. Digestibility analysis of a dog food containing insect meal as the sole source of protein (36.5% inclusion) showed promising results in terms of it presenting similar values as a meat-based diet, indicating its suitability as a sustainable protein source for pet food. Moreover, the study showed that both the in vivo marker method and the in vitro method could be possible alternatives to the traditional total collection method in digestibility trials.