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1.
Heliyon ; 10(15): e35140, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39157330

RESUMO

The functional properties of Andean grain starches of two species, amaranth (Amaranthus caudatus) and canihua (Chenopodium pallidicaule), three cultivars each, were studied. The study focused on chemical composition, pasting properties, thermal properties, water solubility index (WSI), swelling power (SP), and granule morphology. All amaranth starches were waxy starches, with amylose content less than 5 %, which had some differences in chemical composition (p < 0.05). The pasting properties differed between the species, canihua showed more resistance, than amaranth, to heat and shear stress (higher cool paste (CPV) and lower breakdown (BD), ranged between 1250 and 1600 cP and -30 - 10 cP respectively. The amaranth starches presented only similar CPV with 800-1000 cP, while canihua cultivars presented similar PT and BD, and both species presented similar PV, around 1000 cP. Thermal properties (To, Tp, Tc, ΔH, and ΔT) differed among cultivars and species. These differences could be related to the homogeneity molecular structure and content of amylose in canihua cultivars and possibly to genotype factor. Polygonal shapes were the predominant shape of starch granules, ranged 1.0-1.4 µm and 0.8-0.9 µm, for amaranth and canihua starches respectively. Amaranth starches swelled quickly to disintegrate partially at the end, contrary to canihua starches. The thermal and pasting properties were correlated between them. SB, CPV, HPV, CS, were correlated to the content of amylose in canihua starches. One amaranth cultivar was significantly different from the others. Thus, according the functional properties differenced both species and some cultivars in each species. Additionally, the amaranth starch has the potential to be used in the food industry where heat and stress are applied such as extrusion, while canihua starches can be used in desserts or in cosmetic uses, based on their functional properties.

2.
Front Bioeng Biotechnol ; 12: 1415103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39045535

RESUMO

We discuss the role of advanced biotechnology education in fostering sustainable bio-innovation systems. As a case study, we focus on Paraguay's Graduate Diploma in Innovation Management and Biotechnological Projects, which emphasizes interdisciplinary collaboration, stakeholder integration, and professionals skilled in the interplay between biotechnology, society, and governance. We highlight the relevance of educational programs in addressing the gap between academic research and industrial needs, thereby contributing to sustainable growth in the biotechnology sector.

3.
Microorganisms ; 11(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37630439

RESUMO

Zea mays var. amylacea and Zea mays var. indurata are maize ecotypes from Paraguay. Aspergillus section Flavi is the main spoilage fungus of maize under storage conditions. Due to its large intraspecific genetic variability, the accurate identification of this fungal taxonomic group is difficult. In the present study, potential mycotoxigenic strains of Aspergillus section Flavi isolated from Z. mays var. indurata and Z. mays var. amylacea that are marketed in the metropolitan region of Asunción were identified by a polyphasic approach. Based on morphological characters, 211 isolates were confirmed to belong to Aspergillus section Flavi. A subset of 92 strains was identified as Aspergillus flavus by mass spectrometry MALDI-TOF and the strains were classified by MALDI-TOF MS into chemotypes based on their aflatoxins and cyclopiazonic acid production. According to the partial sequencing of ITS and CaM genes, a representative subset of 38 A. flavus strains was confirmed. Overall, 75 A. flavus strains (86%) were characterized as producers of aflatoxins. The co-occurrence of at least two mycotoxins (AF/ZEA, FUM/ZEA, and AF/ZEA/FUM) was detected for five of the Z. mays samples (63%). Considering the high mycological bioburden and mycotoxin contamination, maize marketed in the metropolitan region of Asunción constitutes a potential risk to food safety and public health and requires control measures.

4.
Foods ; 12(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37107529

RESUMO

The canihua (Chenopodium pallidicaule) is a native Andean crop that stands out for its high content of protein, fiber, and minerals and that has a good fatty acid profile. We studied six canihuas cultivars, which were compared according to their proximate, mineral, and fatty acid composition. Based on the form of stems, termed growth habit, they belonged to two groups: decumbent (Lasta Rosada, Illimani, Kullaca, and Cañawiri) and ascending (Saigua L24 and Saigua L25). Dehulling is an important process applied to this grain. However, there is no information about how it affects the chemical composition of the canihua. Dehulling resulted in two levels, whole and dehulled canihua. The highest protein and ash contents were in whole Saigua L25 (19.6 and 5.12 g/100 g, respectively), and the highest fat content was found in dehulled Saigua L25, while the whole grains of Saigua L24 presented the highest fiber content (12.5 g/100 g). Dehulling mainly affected the macro-minerals content, while micro-minerals were only slightly linked to the dehulling. The growth habit influenced the C18:1 and C18:3 contents. In conclusion, the canihua had a nutritional composition influenced by each variety, strongly influenced by dehulling, and to a lesser extent by growth habit.

5.
Int J Biol Macromol ; 49(4): 458-65, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21640751

RESUMO

In this paper we investigate the size, structure and scaling relationships in glycogen isolated from five different animal sources. For this purpose a versatile fractionation technique, asymmetrical flow field-flow fractionation (AsFlFFF), coupled to multi-angle light scattering, is utilized. For determination of the average degree of branching (1)H NMR is utilized. The results give a detailed insight into the physico-chemical properties of glycogen over the whole size distribution. The results show that glycogen is a hyper branched macromolecule with wide size distributions, and in some samples two major populations are clearly observed which most likely correspond to ß- and α-particles of glycogen. The results also illustrates that glycogen is a polysaccharide showing rather diverse conformational properties, over the size distribution, depending on its origin and the extraction procedure. The ratio between root-mean-square radius and hydrodynamic radius varies depending of both sample origin the molar mass of the macromolecules, reflecting differences in conformation and scaling within the size distribution. Thus, a priori assumptions regarding the r(rms)/r(h) are difficult to make and r(rms)/r(h) based on average properties give an incomplete description of the properties. Furthermore, the results display the strength of the apparent density (as obtained from AsFlFFF-MALS-RI) as a characterization parameter for scaling in disperse macromolecules.


Assuntos
Fracionamento por Campo e Fluxo/métodos , Glicogênio/química , Animais , Hordeum/química , Luz , Espectroscopia de Ressonância Magnética , Peso Molecular , Prótons , Espalhamento de Radiação , Amido/química , Fatores de Tempo
6.
Biomacromolecules ; 9(6): 1684-90, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18537296

RESUMO

In this paper we aim to understand the size/conformation relationship in waxy barley starch, a polydisperse and ultrahigh molar mass biomacromolecule. Characterizations are performed with asymmetrical flow field-flow fractionation (AsFlFFF). Furthermore, we study the effect of homogenization on the molar mass, rms radius (r rms) and hydrodynamic radius (r h). For the untreated sample, the macromolecules are elongated objects with low apparent density. As a result of homogenization, molar mass, and r rms decrease, while r h remains unaffected. The process also induces an increase, and scaling with size, of apparent density as well as changes in conformation, represented qualitatively by r rms/ r h. Finally, results from AsFlFFF are compared with viscosimetry and discussed in terms of concentration and close-packing in relation to macromolecular shape and conformation. Hence, the results show that AsFlFFF and our novel methodology enable the determination of several physical properties with high relevance for the solution behavior of polydisperse macromolecules.


Assuntos
Fracionamento por Campo e Fluxo/métodos , Amido/química , Misturas Complexas/química , Hordeum/química , Luz , Conformação Molecular , Tamanho da Partícula , Pressão , Reologia , Espalhamento de Radiação , Viscosidade
7.
Lima; s.n; 2004. 20 p. tab, graf.
Tese em Espanhol | LILACS, LIPECS | ID: lil-666641

RESUMO

OBJETIVO: Identificar las características clínico-epidemiológicas de niños hospitalizados con glomerulonefritis agudas post-estreptocócica (GMN-PE) en el INSN hospitalizados entre el año 2000 al 2010. MATERIAL Y MÉTODOS: Se realizó un estudio de diseño transversal, previa aprobación del comité local de investigación y de ética, se hizo una revisión de historias clínicas de pacientes niños hospitalizados con glomerulonefritis agudas post-estreptocócica en el INSN hospitalizados entre el año 2000 al 2010. Resultados: Se observó que las características más frecuentemente presentadas en niños con GMN-PE son la elevación del ASO, el antecedente epidemiológico más encontrado fue la faringoamigadalitis, más frecuente en niños, el grupo etáreo de mayor incidencia se encontraba entre 7 y 10 años de edad. Además se encontró que la mayoría de los pacientes presentaban niveles de C3 disminuidos...


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Nefropatias , Glomerulonefrite , Pediatria , Prontuários Médicos
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