RESUMO

The search for more environmental friendly herbicides, aiming at the control of agricultural pests, combinated with less harmfulness to human health and the environment has grown. An alternative used by researchers is the application of products of secondary plant metabolism, which are investigated due to their potential bioactivities. Thus, species belonging to the Myrtaceae family are potential in these studies, since this family is recognized for having high biological activity. A species belonging to this genus is Psidium cattleyanum, which has a medicinal effect and its fruits are used in human food. Thus, the objective of this research was to evaluate and compare the phyto-cyto-genotoxicity of aqueous and ethanolic leaf extracts of the specie P. cattleyanum, from plant bioassays, as well as to identify the main classes of compounds present in the extracts. For this, the extracts were prepared, characterized and biological tests were carried out by evaluating, in seeds and seedlings of lettuce and sorghum, the variables: percentage of germination, germination speed index, root growth and aerial growth; and in meristematic lettuce cells the variables: mitotic phases, mitotic index, nuclear alterations and chromosomal alterations. Flavones, flavonones, flavonols, flavononols, flavonoids, alkaloids, resins, xanthones and anthraquinone glycoside were characterized in the ethanolic extract. Both evaluated extracts, in the highest concentration, inhibited the initial plant development. All treatments caused alterations in the mitotic phases and inhibited mitotic index. In addition, the treatments promoted an increase in nuclear and chromosomal alterations. The mechanism of action presented was aneugenic, clastogenic and determined in epigenetic alterations. The ethanolic extract was more cytotoxic, since it had a more expressive effect at a lower concentration. Despite the cytotoxicity of the extracts under study, they promoted alterations at lower levels than the glyphosate positive control.

A busca por herbicidas mais amigáveis ​​ao meio ambiente, visando o controle de pragas agrícolas, aliado a uma menor nocividade à saúde humana e ao meio ambiente tem crescido. Uma alternativa utilizada pelos pesquisadores é a aplicação de produtos do metabolismo secundário de plantas, que são investigados em virtude do seu potencial bioativo. Assim, espécies pertencentes à família Myrtaceae são potenciais nestes estudos, uma vez que esta família é reconhecida por possuir alta atividade biológica. Uma espécie pertencente a este gênero é Psidium cattleyanum, que possui efeito medicinal e seus frutos são utilizados na alimentação humana. Assim, o objetivo desta pesquisa foi avaliar e comparar a fitocitogenotoxicidade de extratos foliares aquosos e etanólicos da espécie P. cattleyanum, a partir de bioensaios vegetais, bem como identificar as principais classes de compostos presentes nos extratos. Para isso, os extratos foram preparados e caracterizados e foram realizados testes biológicos avaliando, em sementes e plântulas de alface e sorgo, as variáveis: porcentagem de germinação, índice de velocidade de germinação, crescimento radicular e crescimento aéreo; em células meristemáticas de alface foram avaliadas as variáveis: fases mitóticas, índice mitótico, alterações nucleares e alterações cromossômicas. Flavonas, flavononas, flavonóis, flavononóis, flavonóides, alcalóides, resinas, xantonas e glicosídeo de antraquinona foram caracterizados no extrato etanólico. Ambos os extratos avaliados, na maior concentração, inibiram o desenvolvimento inicial da planta. Todos os tratamentos causaram alterações nas fases mitóticas e inibiram o índice mitótico. Além disso, os tratamentos promoveram aumento de alterações nucleares e cromossômicas. O mecanismo de ação apresentado foi aneugênico, clastogênico e epigenético. O extrato etanólico foi mais citotóxico, pois teve efeito mais expressivo em menor concentração. Apesar da citotoxicidade dos extratos em estudo, eles promoveram alterações em níveis inferiores ao controle positivo glifosato.

Assuntos

RESUMO

The search for more environmental friendly herbicides, aiming at the control of agricultural pests, combinated with less harmfulness to human health and the environment has grown. An alternative used by researchers is the application of products of secondary plant metabolism, which are investigated due to their potential bioactivities. Thus, species belonging to the Myrtaceae family are potential in these studies, since this family is recognized for having high biological activity. A species belonging to this genus is Psidium cattleyanum, which has a medicinal effect and its fruits are used in human food. Thus, the objective of this research was to evaluate and compare the phyto-cyto-genotoxicity of aqueous and ethanolic leaf extracts of the specie P. cattleyanum, from plant bioassays, as well as to identify the main classes of compounds present in the extracts. For this, the extracts were prepared, characterized and biological tests were carried out by evaluating, in seeds and seedlings of lettuce and sorghum, the variables: percentage of germination, germination speed index, root growth and aerial growth; and in meristematic lettuce cells the variables: mitotic phases, mitotic index, nuclear alterations and chromosomal alterations. Flavones, flavonones, flavonols, flavononols, flavonoids, alkaloids, resins, xanthones and anthraquinone glycoside were characterized in the ethanolic extract. Both evaluated extracts, in the highest concentration, inhibited the initial plant development. All treatments caused alterations in the mitotic phases and inhibited mitotic index. In addition, the treatments promoted an increase in nuclear and chromosomal alterations. The mechanism of action presented was aneugenic, clastogenic and determined in epigenetic alterations. The ethanolic extract was more cytotoxic, since it had a more expressive effect at a lower concentration. Despite the cytotoxicity of the extracts under study, they promoted alterations at lower levels than the glyphosate positive control.

Assuntos