Navegando por Autor "Mantovani, Hilario Cuquetto"

Agora exibindo 1 - 2 de 2

Effects of grain processing methods on the expression of genes involved in volatile fatty acid transport and pH regulation, and keratinization in rumen epithelium of beef cattle
(PLOS ONE, 2018-06-14) Benedeti, Pedro Del Bianco; Silva, Breno de Castro; Pacheco, Marcos Vinıcius Carneiro; Serão, Nicola Vergara Lopes; Carvalho Filho, Ivan; Lopes, Mariana Mescouto; Marcondes, Marcos Inacio; Mantovani, Hilario Cuquetto; Valadares Filho, Sebastião de Campos; Detmann, Edenio; Duarte, Marcio de Souza
Two experiments were carried out to evaluate the effects of corn and sorghum with different processing methods on the expression of genes involved in volatile fatty acids transport and pH regulation, and ruminal keratinization in rumen epithelium of finishing bulls. For Exp. 1, five rumen cannulated Nellore bulls were used in a 5x5 Latin square arrangement, with 14 d for adaptation and 9 d for sample collection. Treatments were: dry ground corn, dry ground sorghum, reconstituted corn, reconstituted sorghum, and control (forage-based diet). Samples of rumen epithelium from ventral sac were excised, rinsed, snap-frozen and stored at -80°C until total RNA isolation and quantitative real-time PCR analysis. In the Exp. 2, 24 Nellore bulls were assigned to a completely randomized design lasting 168 d. Experimental treatments were similar to those at Exp. 1, but without the control treatment. After the experimental period, bulls were slaughtered and rumen epithelium samples were rapidly excised for further histological analysis. Rumen epithelial tissue from animals fed reconstituted corn had lower expression of downregulated-in-adenoma (P = 0.03) and Na+/H+ exchanger 2 (trend; P = 0.09). The expression of Na+/ H+ exchanger 1 (P = 0.10) and putative anion transporter (P = 0.06) tended to be lower in rumen epithelium of bulls fed reconstituted grains. Ruminal concentration of valerate was greater for animals fed reconstituted grain (P = 0.01). Likewise, animals fed reconstituted corn tended to have greater butyrate ruminal concentration (P = 0.08). Keratinized layer thickness did not differ among treatments (P > 0.10). Therefore, reconstituted grains (especially corn) decrease the mRNA expression of genes involved in volatile fatty acids transport and pH control in the rumen epithelium.
Use of response surface methodology for optimization of xylitol production by the new yeast strain Debaryomyces hansenii UFV-170
(Journal of Food Engineering, 2005-08-09) Sampaio, Fábio Coelho; Faveri, Danilo de; Mantovani, Hilario Cuquetto; Passos, Flávia M. Lopes; Perego, Patrizia; Converti, Attilio
Aim of this work was the optimization of xylitol production by Debaryomyces hansenii UFV-170, which already proved to be a new promising xylitol-producing yeast. Two sets of batch bioconversion tests were carried out on synthetic medium, according to two joined 3^3 and 3^2 type full factorial designs, selecting the initial xylose concentration (S0), rotational speed (v) and starting biomass concentration (X0) as independent variables and the maximum xylitol concentration (P), xylitol yield on consumed xylose (YP/S), volumetric productivity (QP) and specific productivity (qP) as response variables. The collected results were then worked out by response surface methodology (RSM). Overall optimization, conducted by overlaying the curves of the responses under investigation, allowed us to point out an optimal range of the independent variables within which the four responses were simultaneously optimized. The point chosen as representative of this optimal area corresponded to S0 = 156 g L^−1, v = 280 rpm and X0 = 6.4 g L^−1, conditions under which the model predicted P = 116.25 g L^−1, YP/S = 0.77 g g^−1, QP = 1.49 g L^−1 h^−1 and qP = 0.16 g g^−1 h^−1.