111 research outputs found

    Comparison of Isolation Methods and Physicochemical Characteristics of Starches Isolated from Red and White Sorghum Hybrids

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    The aim of this study is to optimize starch isolation from different sorghum cultivars and characterize the starch from fourteen red and white sorghum hybrids. Methods involving sulfite maceration and/or protein hydrolysis are assayed. Recovery and yield, residual protein, total and starch damage, whiteness index (WI), water absorption, solubility, and swelling power of isolated starches are compared in order to select the appropriate isolation method. Results indicate that starch recoveries between 44–76%. Isolated starches present 0.58–2.4 g 100 g−1 residual proteins, 89.1–90.6 WI, 5.10–9.57 g 100 g−1 solubility, and 15.09–22.57 g water 100 g−1 swelling power. Taking into account recovery, residual protein, WI, and good hydration properties of starch, the maceration during 24 h combined with protein hydrolysis during 3 h is used to isolate starches. After starch isolation, its characterization (residual protein, total and damage starch, amylose content, particle size distribution, WI, crystallinity, gelatinization temperature, water absorption, solubility, and swelling power) is performed. Principal component analysis shows that color as indicator of variety is influenced by the structure, composition, and physicochemical properties of isolated starch. Starches from white sorghum hybrids have higher amylose content and gelatinization temperature than the red ones, which affect starch solubility, and swelling power.Fil: AlbarracĂ­n, Micaela. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentin

    Influence of pH on colour and iron content of peptide fractions obtained from bovine Hb concentrate hydrolysates

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    The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex- 6-L (P), Fungal?Protease?Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty-four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained.Fil: Cian, RaĂșl Esteban. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: GonzĂĄlez, Rolando J.. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentin

    Bioactive properties of peptides obtained by enzymatic hydrolysis from protein

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    The traditional method to obtain phycocolloids from seaweeds implies successive extraction steps with cold and hot water. The first cold water extract has no phycocolloids but is rich in proteins and is considered a waste. Four hydrolysates were obtained using trypsin, alcalase and a combination of both sequentially added from a first cold water protein extract (PF) derived from Porphyra columbina. PF hydrolysates (PFH) were enriched in peptides with low molecular weight containing Asp, Ala and Glu. Both PF and PFH showed immunosuppressive effects on rat splenocytes as they enhanced IL-10 production while the production of TNFa and IFNg was inhibited. These immunosuppressive effects were higher for PFH. PFH had antihypertensive activity (> 35% of ACE inhibition) and antioxidant capacity (DPPH, TEAC, ORAC and copper-chelating activity). The hydrolysis could be used as a mean to obtain bioactive peptides from algae protein byproducts and to add value to the phycocolloids extraction process.Fil: Cian, RaĂșl Esteban. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: MartĂ­nez Augustin, Olga. Universidad de Granada; EspañaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentin

    Effect of cultivars and planting date on yield, oil content, and fatty acid profile of flax varieties (Linum usitatissimum L.)

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    In order to determine the effect of cultivars and planting date on flax fatty acid profile, seed yield, and oil content, an assay with seven cultivars (Baikal, Prointa Lucero, Prointa Ceibal, PanambĂ­ INTA, CurundĂș INTA, CarapĂ© INTA, and Tape INTA) was carried out at Parana Agricultural Experimental Station, Argentina. Significant differences among cultivars were found for content of palmitic (5–7 g/100 g), stearic (5–8 g/100 g), linoleic (13–19 g/100 g), saturated (11–15 g/100 g), and unsaturated acids (92–96 g/100 g) within the seven cultivars. The best seed yields were observed in Prointa Lucero and CarapĂ© INTA varieties (2091.50 kg·ha−1 and 2183.34 kg·ha−1, respectively) in the first planting date and in CarapĂ© INTA and Prointa Lucero (1667 kg·ha−1 and 1886 kg·ha−1, respectively) in the second planting date. A delayed planting date had a negative effect on seed yield (1950 kg·ha−1 and 1516 kg·ha−1) and oil content (845 kg·ha−1 and 644 kg·ha−1) but did not affect oil composition.Fil: Gallardo, Maricel Andrea. Instituto Nacional de TecnologĂ­a Agropecuaria. Centro Regional Entre Rios. EstaciĂłn Experimental Agropecuaria Parana; ArgentinaFil: Milisich, HĂ©ctor JosĂ©. Instituto Nacional de TecnologĂ­a Agropecuaria. Centro Regional Entre Rios. EstaciĂłn Experimental Agropecuaria Parana; ArgentinaFil: Drago, Silvina Rosa. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: GonzĂĄlez, Rolando JosĂ©. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de Alimentos; Argentin

    Isolation and identification of cholesterol esterase and pancreatic lipase inhibitory peptides from brewer’s spent grain by consecutive chromatography and mass spectrometry

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    The isolation and identification of cholesterol esterase (CE) and pancreatic lipase (PL) inhibitory peptides obtained from the protein hydrolysate of brewer's spent grain (BSG) was performed. BSG peptides were fractionated and purified sequentially by anion exchange, gel filtration (FPLC), and reversed phase high-performance liquid chromatography (RP-HPLC). The fractions obtained from each chromatographic step were collected and the in vitro enzyme inhibitory activity was evaluated. The chromatographic purification process increased the in vitro activities. The most active fractions were evaluated using MALDI-TOF tandem mass spectrometry, which identified three peptides: a peptide with the highest CE inhibition capacity (WNIHMEHQDLTTME) and two peptides with PL inhibition capacity (DFGIASF and LAAVEALSTNG). These three peptides showed hydrophobic and acidic amino acid residues (Asp and Glu) and/or their amines (Asn and Gln), which could be a common feature among lipid-lowering peptides related to CE and PL enzyme inhibition. The in silico studies showed that the three peptides had high hydrophobicity and were susceptible to enzymatic hydrolysis performed by trypsin, pepsin, and pancreatin. The BSG byproduct was a good source of CE and PL inhibitory peptides, thus adding value to this byproduct of the beer industry. This is the first report to demonstrate that BSG peptides can inhibit CE and PL enzymes. This journal isFil: GarzĂłn, Antonela Guadalupe. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: Cian, RaĂșl Esteban. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: Aquino, MarilĂ­n EstefanĂ­a. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: Drago, Silvina Rosa. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentin

    Identification and in silico study of a novel dipeptidyl peptidase IV inhibitory peptide derived from green seaweed Ulva spp. hydrolysates

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    A number of functional foods containing seaweed-derived peptides are currently commercialized. Some seaweed derived peptide-containing products include Wakame peptideÂź and Nori peptide SÂź. To develop functional foods with the addition of Ulva spp. peptides, the isolation and identification of dipeptidyl peptidase IV (DPP-IV) inhibitory peptides from hydrolysates of this seaweed was performed. Ulva spp. peptides were fractionated and purified sequentially by anion exchange, ultrafiltration, and reversed phase high performance liquid chromatography. The fractions obtained from each analytical step were collected and the in vitro enzyme inhibitory activity was evaluated. The applied purification process increased the in vitro DPP-IV inhibitory activity. The inhibition mechanism of DPP-IV of the most active fraction was evaluated and it was analyzed by MALDI-TOF. A peptide SLAVSVH was identified. It has 57% of hydrophobic residues in their sequence (including Ala and branched chain amino acids), which could be a common feature among inhibitory peptides of DPP-IV. Molecular docking analysis showed that SLAVSVH/DPP-IV complex was stabilized by CH–π interactions between the side chains of Val6 with the indol of Trp629, and between rings of His7 with Trp563. The energy values obtained for the peptide under study indicate that it is a good candidate to inhibit DPP-IV.Fil: Cian, RaĂșl Esteban. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: Nardo, Agustina Estefania. Provincia de Buenos Aires. GobernaciĂłn. ComisiĂłn de Investigaciones CientĂ­ficas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos; ArgentinaFil: GarzĂłn, Antonela Guadalupe. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: Añon, Maria Cristina. Provincia de Buenos Aires. GobernaciĂłn. ComisiĂłn de Investigaciones CientĂ­ficas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos; ArgentinaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentin

    Hydrolyzates from Pyropia columbina seaweed have antiplatelet aggregation, antioxidant and ACE I inhibitory peptides which maintain bioactivity after simulated gastrointestinal digestion

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    The aim of this work was to evaluate the bio-accessibility of bioactive peptides with ACE I inhibition, antioxidant and antiplatelet aggregation activity obtained by enzymatic hydrolysis of Pyropia columbina proteins. Two hydrolyzates were produced (A and AF). Bio-accesibility was determined using a gastrointestinal digestion (pepsin and pancreatin) and membrane dialysis system. Hydrolyzates had peptides with medium molecular weight (2300 Da), and Asp, Glu and Ala were the most abundant amino acids. Additionally, AF presented small peptides with 287 Da. Peptides from A showed the highest angiotensin-converting enzyme activity (ACE I) inhibition by uncompetitive mechanism (IC50%, 1.2 ± 0.1 g L−1), and ÎČ-carotene bleaching inhibition. Peptides from AF presented the lower IC50% value for ABTS+‱ and DPPH radical inhibition, the highest copper-chelating activity (CCA), and antiplatelet aggregation activity. In vitro gastrointestinal digestion increased ABTS+‱ and DPPH scavenging and CCA of both hydrolyzates. Antiplatelet aggregation activity of A peptides was increased after simulated digestion process (≈157%). Peptides from both hydrolyzates were potentially bio-accessible, maintaining overall the bioactivity after gastrointestinal digesFil: Cian, RaĂșl Esteban. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: GarzĂłn, Antonela Guadalupe. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: Betancur, Ancona, David. Universidad AutĂłnoma de YucatĂĄn; MĂ©xicoFil: Chel Guerrero, Luis. Universidad AutĂłnoma de YucatĂĄn; MĂ©xicoFil: Drago, Silvina Rosa. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentin

    Physical, structural and antioxidant properties of brewer's spent grain protein films

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    The development of brewer's spent grain protein (BSG‐PC) films with potential active packaging properties was investigated. Films were prepared by casting protein dispersions at different pH values (2, 8, 11), plasticizers [polyethylene glycol (PEG) or glycerol] and levels (0–0.25 g g−1) of PEG. Mechanical, water‐barrier and solubility, optical, antioxidant (reducing power, ABTS‱+ and lipidic radical scavenging), and antimicrobial properties of films were determined. Also, the structural characteristics of films were evaluated by attenuated total reflectance‐Fourier transform infrared spectroscopy.Fil: Proaño Miniguano, Janina Lissette. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Salgado, Pablo Rodrigo. Provincia de Buenos Aires. GobernaciĂłn. ComisiĂłn de Investigaciones CientĂ­ficas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos; ArgentinaFil: Cian, RaĂșl Esteban. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; ArgentinaFil: Mauri, Adriana Noemi. Provincia de Buenos Aires. GobernaciĂłn. ComisiĂłn de Investigaciones CientĂ­ficas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimentos; ArgentinaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentin

    Immunomodulatory properties of the protein fraction from Phorphyra columbina

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    The phycobiliproteins from Rhodophyta, R-phycoerythrin (R-PE) and C-phycocyanin (C-PC), have been shown to exert immunomodulatory effects. This study evaluated the effects of a Phorphyra columbina protein fraction (PF) and R-PE and C-PC on rat primary splenocytes, macrophages, and T-lymphocytes in vitro. PF featured various protein species, including R-PE and C-PC. PF showed mitogenic effects on rat splenocytes and was nontoxic to cells except at 1 g L-1 protein. IL-10 secretion was enhanced by PF in rat splenocytes, macrophages, and especially T-lymphocytes, whereas it was markedly diminished by R-PE and C-PC. The production of pro-inflammatory cytokines by macrophages was inhibited. The effect of PF on IL-10 was evoked by JNK/p38 MAPK and NF-ÎșB-dependent pathways in macrophages and T-lymphocytes. It was concluded that PF has immunomodulatory effects on macrophages and lymphocytes that appear to be predominantly anti-inflammatory via up-regulated IL-10 production and cannot be accounted for by R-PE and C-PC.Fil: Cian, RaĂșl Esteban. Instituto Nacional de TecnologĂ­a Agropecuaria. Centro de InvestigaciĂłn de Agroindustria. Instituto de TecnologĂ­a de Alimentos; Argentina. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: LĂłpez Posadas, RocĂ­o. Universidad de Granada; EspañaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: SĂĄnchez De Medina, FermĂ­n. Universidad de Granada; EspañaFil: MartĂ­nez Augustin, Olga. Universidad de Granada; Españ

    Study of the Interaction of Phaseolus lunatus Hydrolysed Proteins and Delonix regia Carboxymethylated Gum Using Capillary Electrophoresis

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    Proteins and gums are commonly employed in the manufacture of processed foods. The knowledge of the degree of interaction between these two types of biopolymers is important for the development of new products and processes. In this work, the interaction of protein hydrolysate (PH) of Phaseolus lunatus with carboxymethylated flamboyant gum (CFG) was evaluated. Capillary electrophoresis technique was performed using a P/ACE MDQ equipment with diode array detector at 220 nm, using a 50 ÎŒm I.D. bare fused-silica capillary, with a 20 cm effective length, operating at 5 kV for injection and separation in reverse polarity at 15 kV and 25 °C. PH presented 7 main protein components of 8.3, 11.2, 12.9, 17.0, 19.1, 28.7 and 56.4 kDa. A standard curve with different concentrations of hydrolysed protein (3.8 to 8.6 g/L) was prepared by linking the relative peak height for each component present in the protein hydrolysate to its concentration. To determine the existence of PH-CFG interaction, protein-gum mixtures using different concentrations of PH and keeping constant the concentration of CFG at 2 or 2.8 g/ L were evaluated. Interaction PH-CFG was observed at 1.8-2.9 protein / gum ratios. Protein components of PH presented a tendency to join to CFG in a greater extent at lower molecular weight. Protein components higher than 20 kDa remain free in PH-CFG systems.Fil: Corzo Rios, Luis Jorge. Universidad AutĂłnoma de YucatĂĄn; MĂ©xico. Instituto PolitĂ©cnico Nacional; MĂ©xicoFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de IngenierĂ­a QuĂ­mica. Instituto de TecnologĂ­a de los Alimentos; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe; ArgentinaFil: Gallegos TintorĂ©, Santiago. Universidad AutĂłnoma de YucatĂĄn; MĂ©xicoFil: Betancur Ancona, David. Universidad AutĂłnoma de YucatĂĄn; MĂ©xicoFil: Chel Guerrero, Luis. Instituto PolitĂ©cnico Nacional; MĂ©xic
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