Alicia Ayerdi | Unilasalle - Academia.edu (original) (raw)

Papers by Alicia Ayerdi

Phyton

Resumen. En girasol, la selección convencional es ampliamente utilizada para la modificación de c... more Resumen. En girasol, la selección convencional es ampliamente utilizada para la modificación de caracteres como la composición en ácidos grasos, la resistencia a enfermedades, y especialmente la obtención de aceites comerciales con un alto contenido en ácido oleico. Hay un creciente interés en los tocoferoles y en los fitoesteroles, presentes en el girasol, por sus propiedades benéficas sobre la salud humana. Esto enfatiza la necesidad de estudios de programas de selección por estos componentes bioactivos. Un centenar de parejas isogénicas de híbridos y líneas parentales de girasol clásico y su versión oleica fueron cultivados entre 2003 y 2006 en diferentes lugares en Francia. Los resultados indicaron que el girasol es rico en α-tocoferol y en β-sitoesterol. Sin embargo, hubo muy poca correlación entre el aceite de girasol tradicional linoléico y el rico en ácido oleico, en lo que respecta la a cantidad total de tocoferoles, y ninguna correlación con respecto a la cantidad de fitoesteroles totales. Por otra parte, no hubo casi o ningún efecto de la conversión de ácido oleico sobre las cantidades de tocoferoles y de fitoesteroles. No obstante, la cantidad de tocoferoles fue significativamente inferior en el girasol oleico que en el clásico, pero solo en algunos años.

Tocopherols are the most important compounds having antioxidant activity in sunflower's seeds, an... more Tocopherols are the most important compounds having antioxidant activity in sunflower's seeds, and phytosterols are natural constituents of vegetable oils and are known for their cholesterol-lowering properties. A sunflower oil with a high tocopherol and phytosterol content is interesting because a part of oil's antioxidants is destroyed during the industry processing . The literature concerning the effect of temperature during plant growth on tocopherol content is controversial. In field conditions, the tocopherol content in sunflower oil varied in response to planting location , or planting location and sowing date (Roche et al 2005), two management practices that often expose plants to different temperatures. As far as we know, genetic control of tocopherol and phytosterol content in sunflower oil under water-stress conditions is not well reported in the literature. The purpose of this study was to identify QTLs controlling tocopherol and phytosterol content in sunflower oil in well-watered and water-stress conditions.

Oléagineux, Corps gras, Lipides, 2010

Sunflower oil is widely consumed in France and Spain. This oil has a good reputation among consum... more Sunflower oil is widely consumed in France and Spain. This oil has a good reputation among consumers, due to its high polyunsaturated fatty acid content. Thirty years after its discovery, the oleic mutation (high C18:1 contents) has now reached agricultural production, with fast increasing surfaces for the last three years. The challenge is now the production of very high oleic (> 90%) sunflowers and new fatty acid profiles, such as high linoleic, palmitic, stearic or stearic + oleic hybrids, which are of high interest for chemistry or food industry. The problem is now the stability of the expression in varying genetic backgrounds, and the understanding of environmental effects. Minor components are also a main strength of sunflower oil: its high tocopherols (Vitamin E) content (0,5 to 1%) is all the more interesting for nutritionists that they be almost exclusively α-tocopherol (> 95%), which is the most vitaminic active component. Nowadays, the unraveling of tocopherols biosynthesis and its key points of regulation is in progress. New tocopherol profiles have been recently obtained. Higher protective effects are attributed to γor δ-tocopherols. They could increase the stability of oils or margarines. Genetic progress for total content is possible, as in sunflower like in other oilseed crops, heritability is rather high (> 0.7). Sunflower oil also contains twice as much phystosterols as olive oil (3 vs 1,5%), and mainly β-sitosterol. Major mutations of this pathway can induce penalizing phenotypic modifications: 1) campesterol is the precursor of plant hormones brassinosteroids, and 2) stigmasterol/campesterol ratio is also implied in plant growth regulation. However, hybrids can significantly differ in their total content. Either for fatty acids or minor components, breeding programs for new profiles, or higher contents, need high throughout oil extraction and analysis. Chemometric analysis offer interesting solutions despite their need of large sets of reference analysis.

Phyton

Resumen. En girasol, la selección convencional es ampliamente utilizada para la modificación de c... more Resumen. En girasol, la selección convencional es ampliamente utilizada para la modificación de caracteres como la composición en ácidos grasos, la resistencia a enfermedades, y especialmente la obtención de aceites comerciales con un alto contenido en ácido oleico. Hay un creciente interés en los tocoferoles y en los fitoesteroles, presentes en el girasol, por sus propiedades benéficas sobre la salud humana. Esto enfatiza la necesidad de estudios de programas de selección por estos componentes bioactivos. Un centenar de parejas isogénicas de híbridos y líneas parentales de girasol clásico y su versión oleica fueron cultivados entre 2003 y 2006 en diferentes lugares en Francia. Los resultados indicaron que el girasol es rico en α-tocoferol y en β-sitoesterol. Sin embargo, hubo muy poca correlación entre el aceite de girasol tradicional linoléico y el rico en ácido oleico, en lo que respecta la a cantidad total de tocoferoles, y ninguna correlación con respecto a la cantidad de fitoesteroles totales. Por otra parte, no hubo casi o ningún efecto de la conversión de ácido oleico sobre las cantidades de tocoferoles y de fitoesteroles. No obstante, la cantidad de tocoferoles fue significativamente inferior en el girasol oleico que en el clásico, pero solo en algunos años.

Tocopherols are the most important compounds having antioxidant activity in sunflower's seeds, an... more Tocopherols are the most important compounds having antioxidant activity in sunflower's seeds, and phytosterols are natural constituents of vegetable oils and are known for their cholesterol-lowering properties. A sunflower oil with a high tocopherol and phytosterol content is interesting because a part of oil's antioxidants is destroyed during the industry processing . The literature concerning the effect of temperature during plant growth on tocopherol content is controversial. In field conditions, the tocopherol content in sunflower oil varied in response to planting location , or planting location and sowing date (Roche et al 2005), two management practices that often expose plants to different temperatures. As far as we know, genetic control of tocopherol and phytosterol content in sunflower oil under water-stress conditions is not well reported in the literature. The purpose of this study was to identify QTLs controlling tocopherol and phytosterol content in sunflower oil in well-watered and water-stress conditions.

Oléagineux, Corps gras, Lipides, 2010

Sunflower oil is widely consumed in France and Spain. This oil has a good reputation among consum... more Sunflower oil is widely consumed in France and Spain. This oil has a good reputation among consumers, due to its high polyunsaturated fatty acid content. Thirty years after its discovery, the oleic mutation (high C18:1 contents) has now reached agricultural production, with fast increasing surfaces for the last three years. The challenge is now the production of very high oleic (> 90%) sunflowers and new fatty acid profiles, such as high linoleic, palmitic, stearic or stearic + oleic hybrids, which are of high interest for chemistry or food industry. The problem is now the stability of the expression in varying genetic backgrounds, and the understanding of environmental effects. Minor components are also a main strength of sunflower oil: its high tocopherols (Vitamin E) content (0,5 to 1%) is all the more interesting for nutritionists that they be almost exclusively α-tocopherol (> 95%), which is the most vitaminic active component. Nowadays, the unraveling of tocopherols biosynthesis and its key points of regulation is in progress. New tocopherol profiles have been recently obtained. Higher protective effects are attributed to γor δ-tocopherols. They could increase the stability of oils or margarines. Genetic progress for total content is possible, as in sunflower like in other oilseed crops, heritability is rather high (> 0.7). Sunflower oil also contains twice as much phystosterols as olive oil (3 vs 1,5%), and mainly β-sitosterol. Major mutations of this pathway can induce penalizing phenotypic modifications: 1) campesterol is the precursor of plant hormones brassinosteroids, and 2) stigmasterol/campesterol ratio is also implied in plant growth regulation. However, hybrids can significantly differ in their total content. Either for fatty acids or minor components, breeding programs for new profiles, or higher contents, need high throughout oil extraction and analysis. Chemometric analysis offer interesting solutions despite their need of large sets of reference analysis.