Physicochemical changes of pepsin-solubilized and insoluble collagen in jumbo squid (Dosidicus gigas) muscle after cooking process

Collagen is the major connective tissue (CT) protein and one of the main constituents of the jumbo squid (Dosidicus gigas). Therefore, physicochemical changes of pepsin-solubilized collagen (PSC) and insoluble collagen (IC) were studied after cooking (100°C/30 min) of muscle (mantle, fins, and arms). Different pyridinoline (Pyr) contents (the major cross-linking molecule in collagen fibers) were found in the fresh muscle of the three anatomical regions. After the cooking process, a decrease from 10 to 30% in the thermal resistance of collagen was observed, depending on the anatomical region and fraction evaluated. Furthermore, the electrophoretic profile, Fourier transform infrared (FTIR) spectroscopy, and the amino-acid profile revealed that structural changes occurred in the two different collagen fractions caused by the thermal process, and the changes were greater in the mantle. Under the conditions applied in this study, collagen fractions from the squid arms showed more stability during the cooking process due to the high cross-linking degree of their fibers

Control of mycotoxigenic fungi with microcapsules of essential oils encapsulated in chitosan

Abstract Aspergillus and Fusarium are the fungi genera most frequently isolated from cereal grains and other commodities. They are capable of producing mycotoxins, which can affect the human and animal health. Synthetic fungicides have been used to control these fungi, nevertheless, they have acquired resistance and other alternatives are necessary since they now need higher amounts. Therefore, the aim of this study was to evaluate the efficacy of cinnamon, clove and thyme essential oils (EOs) alone and encapsulated in chitosan on the radial growth, spore germination and mycotoxin production by Fusarium verticillioides and Aspergillus parasiticus. The composition of the EOs was determined by gas chromatography mass spectrometry (GC-MS). EOs inhibited radial growth and spore germination of both fungal species better than when they were encapsulated, plus, they reduced mycotoxin production. The major components were eugenol in cinnamon and clove EO (70 and 63%, respectively) and 2-methyl-5-(1-methyethyl)-phenol (46.2%) in thyme EO. The microparticles with clove and thyme EO showed good surface charges, higher than +30 mV and their average size for the three types of microparticles was about 750 nm. Our findings suggest that EOs both alone and encapsulated in chitosan have a fungistatic effect on Fusarium verticillioides and Aspergillus parasiticus

Revista Mexicana de Micología Antifungal activity of methanolic extracts of Jacquinia macrocarpa and Krameria erecta on the growth of Fusarium verticillioides and effect on fumonisin production

Actividad antifúngica de extractos metanólicos de Jacquinia macrocarpa y Krameria erecta en el crecimiento de Fusarium verticillioides y su efecto en la producción de fumonisinas RESUMEN Algunas plantas medicinales han sido estudiadas sobre hongos fitopatógenos para conocer si tienen propiedades antifúngicas, por ello en este estudio se evaluaron los extractos metanólicos de hojas de Jacquinia macrocarpa y Krameria erecta sobre el crecimiento radial, germinación de esporas y producción de biomasa por Fusarium moniliforme en medio agar papa dextrosa. El extracto de J. macrocarpa que presentó mejores resultados fue particionado con hexano, acetato de etilo y n-butanol. Solo la fracción butanólica presentó actividad, ya que retardó la germinación de esporas y el crecimiento de las colonias cambió de radial a apical, que indica que el hongo está estresado. La producción de fumonisina no fue afectada por el extracto. Se concluye que el extracto metanólico de J. macrocarpa y su fracción butanólica son capaces de retardar el crecimiento de F. verticillioides in vitro y no afectan la producción de fumonisinas. PALABRAS CLAVE: germinación de esporas, crecimiento radial, micotoxinas. ABSTRACT Some medicinal plants have been studied on phytopathogenic fungi for their antifungal activity. For this reason the goal of this study was to evaluate methanolic extract of Jacquinia macrocarpa and Krameria erecta on radial growth, spore germination, biomass production of Fusarium verticillioides. Methanolic extract of J. macrocarpa which caused the best results was sequentially partitioned with hexane, ethyl acetate and n-butanol. Only the butanolic fraction was active. It delayed the spore germination and the colony growth changed from radial to apical, which is a way to express it is under pressure due to chemicals present in the fraction. Fumonisin production was not affected by the extract. We conclude that J. macrocarpa methanolic extract and its butanolic fraction are capable to delay the radial growth of F. verticillioides and the kinetic of spore germination and do not affect fumonisin production

Revista Mexicana de Micología Antifungal activity of methanolic extracts of Jacquinia macrocarpa and Krameria erecta on the growth of Fusarium verticillioides and effect on fumonisin production Revista Mexicana de Micología Antifungal activity of methanol

Actividad antifúngica de extractos metanólicos de Jacquinia macrocarpa y Krameria erecta en el crecimiento de Fusarium verticillioides y su efecto en la producción de fumonisinas RESUMEN Algunas plantas medicinales han sido estudiadas sobre hongos fitopatógenos para conocer si tienen propiedades antifúngicas, por ello en este estudio se evaluaron los extractos metanólicos de hojas de Jacquinia macrocarpa y Krameria erecta sobre el crecimiento radial, germinación de esporas y producción de biomasa por Fusarium moniliforme en medio agar papa dextrosa. El extracto de J. macrocarpa que presentó mejores resultados fue particionado con hexano, acetato de etilo y n-butanol. Solo la fracción butanólica presentó actividad, ya que retardó la germinación de esporas y el crecimiento de las colonias cambió de radial a apical, que indica que el hongo está estresado. La producción de fumonisina no fue afectada por el extracto. Se concluye que el extracto metanólico de J. macrocarpa y su fracción butanólica son capaces de retardar el crecimiento de F. verticillioides in vitro y no afectan la producción de fumonisinas. PALABRAS CLAVE: germinación de esporas, crecimiento radial, micotoxinas. ABSTRACT Some medicinal plants have been studied on phytopathogenic fungi for their antifungal activity. For this reason the goal of this study was to evaluate methanolic extract of Jacquinia macrocarpa and Krameria erecta on radial growth, spore germination, biomass production of Fusarium verticillioides. Methanolic extract of J. macrocarpa which caused the best results was sequentially partitioned with hexane, ethyl acetate and n-butanol. Only the butanolic fraction was active. It delayed the spore germination and the colony growth changed from radial to apical, which is a way to express it is under pressure due to chemicals present in the fraction. Fumonisin production was not affected by the extract. We conclude that J. macrocarpa methanolic extract and its butanolic fraction are capable to delay the radial growth of F. verticillioides and the kinetic of spore germination and do not affect fumonisin production

Control of mycotoxigenic fungi with microcapsules of essential oils encapsulated in chitosan

<div><p>Abstract Aspergillus and Fusarium are the fungi genera most frequently isolated from cereal grains and other commodities. They are capable of producing mycotoxins, which can affect the human and animal health. Synthetic fungicides have been used to control these fungi, nevertheless, they have acquired resistance and other alternatives are necessary since they now need higher amounts. Therefore, the aim of this study was to evaluate the efficacy of cinnamon, clove and thyme essential oils (EOs) alone and encapsulated in chitosan on the radial growth, spore germination and mycotoxin production by Fusarium verticillioides and Aspergillus parasiticus. The composition of the EOs was determined by gas chromatography mass spectrometry (GC-MS). EOs inhibited radial growth and spore germination of both fungal species better than when they were encapsulated, plus, they reduced mycotoxin production. The major components were eugenol in cinnamon and clove EO (70 and 63%, respectively) and 2-methyl-5-(1-methyethyl)-phenol (46.2%) in thyme EO. The microparticles with clove and thyme EO showed good surface charges, higher than +30 mV and their average size for the three types of microparticles was about 750 nm. Our findings suggest that EOs both alone and encapsulated in chitosan have a fungistatic effect on Fusarium verticillioides and Aspergillus parasiticus.</p></div