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1.
Med Pregl ; 62 Suppl 3: 105-10, 2009.
Artigo em Sérvio | MEDLINE | ID: mdl-19702127

RESUMO

The sunflower is the main oil crop in Serbia and one of the four major oil crops on the global scale. The seed of commercial sunflower crops being grown today consists most commonly of 45-53% oil and 15-18% protein. Unfortunately, sunflower seed protein has traditionally been underused in the human diet in Serbia. The amino acid composition of sunflower protein is quite favorable. In addition to oil and protein, sunflower kernels contain tocopherols, minerals, and vitamins. The sunflower is also a major honey plant, as sunflower plants produce over 40 kg of nectar and over 80 kg of pollen per area unit (hectare) under normal circumstances. Standard sunflower oil is linoleic in character, but induced mutations have been used to obtain genotypes with a high-oleic acid content of the oil (> 85%), thus enabling the development of high-oleic sunflower hybrids. Induced mutations have also been used to obtain genotypes with high levels of palmitic, stearic, and linoleic acids. The predominant tocopherol in standard sunflower oil is the alpha one, but sunflower genotypes have now been developed using spontaneous and induced mutations that predominantly contain beta, gamma, and delta tocopherols. Various developments in the field of genetics have made it possible to develop sunflower hybrids with different oil profiles in terms of fatty acid composition and tocopherol type and amount. The thermo-oxidative stability of the new types of sunflower oil is significantly higher than that of standard sunflower oil. Of the new types of sunflower, it is the high-oleic hybrids that have found the widest application in commercial production. It is expected that the future sunflower hybrids combining high levels of oleic and stearic acids with gamma tocopherol will become a major component of a healthy human diet. The development of new consumption sunflower hybrids with an increased protein content and altered oil quality will lead to the development of a large number of novel final products based on sunflower kernel that willfurther improve human nutrition.


Assuntos
Helianthus , Necessidades Nutricionais , Óleos de Plantas/administração & dosagem , Sementes , Helianthus/química , Humanos , Valor Nutritivo , Óleos de Plantas/química , Proteínas de Vegetais Comestíveis/análise , Sementes/química , Óleo de Girassol
2.
Can J Physiol Pharmacol ; 86(4): 215-21, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18418432

RESUMO

The sunflower is one of the four most important oilseed crops in the world, and the nutritional quality of its edible oil ranks among the best vegetable oils in cultivation. Typically up to 90% of the fatty acids in conventional sunflower oil are unsaturated, namely oleic (C 18:1, 16%-19%) and linoleic (C 18:2, 68%-72%) fatty acids. Palmitic (C 16:0, 6%), stearic (C 18:0, 5%), and minor amounts of myristic (C 14:0), myristoleic (C 14:1), palmitoleic (C 16:1), arachidic (C 20:0), behenic (C 22:0), and other fatty acids account for the remaining 10%. Advances in modern genetics, most importantly induced mutations, have altered the fatty acid composition of sunflower oil to a significant extent. Treating sunflower seeds with gamma- and X-rays has produced mutants with 25%-30% palmitic acid. Sunflower seed treatment with X-rays has also resulted in mutants having 30% palmitoleic acid, while treatments with mutagenic sodium azide have produced seeds containing 35% stearic acid. The most important mutations have been obtained by treatment with dimethyl sulfate, which produced genotypes with more than 90% oleic acid. Mutants have also been obtained that have a high linoleic acid content (>80%) by treating seeds with X-rays and ethyl methanesulfonate. Of the vitamin E family of compounds, sunflower oil is known to predominantly contain alpha-tocopherol (>90%). Spontaneous mutations controlled by recessive genes have been discovered that significantly alter tocopherol forms and levels. The genes in question are tph(1) (50% alpha- and 50% beta-tocopherol), tph(2) (0%-5% alpha- and 95%-100% gamma-tocopherol), and tph(1)tph(2) (8%-40% alpha-, 0%-25% beta-, 25%-84% gamma-, and 8%-50% delta-tocopherol). The existence of (mutant) genes for increased levels of individual fatty acids and for different forms and levels of tocopherol enables the development of sunflower hybrids with different oil quality. The greatest progress has been made in developing high-oleic hybrids (>90% oleic acid). There has been considerable work done recently on the development of high-oleic hybrids with altered tocopherol levels, the oil of which will have 10-20 times greater oxidative stability than that of conventional sunflower oil. While sunflower breeders work on developing hybrids with altered oil quality, medical scientists in general and nutritionists in particular will determine the parameters for the use of these novel types of oil that can improve human nutrition and be used in the prevention of cardiovascular diseases.


Assuntos
Ácidos Graxos/análise , Alimentos Geneticamente Modificados , Regulação da Expressão Gênica de Plantas , Helianthus/genética , Mutação , Óleos de Plantas/química , Plantas Geneticamente Modificadas , Tocoferóis/análise , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Helianthus/química , Helianthus/efeitos dos fármacos , Helianthus/enzimologia , Helianthus/efeitos da radiação , Isoenzimas/genética , Metabolismo dos Lipídeos/genética , Mutagênicos/farmacologia , Mutação/efeitos dos fármacos , Mutação/efeitos da radiação , Óleos de Plantas/metabolismo , Óleos de Plantas/normas , Proteínas de Plantas/genética , Controle de Qualidade , Sementes , Óleo de Girassol , Tocoferóis/metabolismo , Triptofano Hidroxilase/genética , Raios X
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