Resumo
Os inibidores de proteinases são proteínas extensivamente investigadas nos tecidos de estocagem, mas pouco prospectadas em outros tecidos vegetais. O objetivo deste estudo foi detectar a presença de inibidores de serinoproteinases em extratos foliares de quinze espécies de leguminosas arbóreas da Amazônia. As espécies estudadas foram: Caesalpinia echinata, C. ferrea, Cedrelinga cateniformis, Copaifera multijuga, Dinizia excelsa, Enterolobium contortisiliquum, E. maximum, E. schomburgkii, Leucaena leucocephala, Ormosia paraensis, Parkia multijuga, P. pendula, P. platycephala, Swartzia corrugata e S. polyphylla. Folhas foram coletadas, secas a 30ºC durante 48 h, trituradas e submetidas à extração com NaCl (0,15 M, 10 por cento p/v) resultando no extrato total. Ensaios foram executados para determinar a concentração de proteínas e detectar a atividade inibitória contra a tripsina e quimotripsina bovina. Os teores de proteínas bruta e solúvel nos extratos foliares variaram de 7,9 a 31,2 por cento e 1,3 a 14,8 por cento, respectivamente. A atividade inibitória sobre a tripsina e quimotripsina foi observada em todos os extratos foliares. Contudo, nos extratos de E. maximum, L. leucocephala, P. pendula, S. corrugata e S. polyphylla a inibição foi maior sobre a tripsina, enquanto o extrato de P. multijuga foi mais efetivo contra a quimotripsina. Nós concluímos que nos extratos foliares de leguminosas arbóreas têm inibidores de serinoproteinases e exibem potencial aplicações biotecnológicas.
The proteinase inhibitors are proteins extensively investigated in tissue storage, but few prospected in other plant tissues. The aim of this study was to detect the presence of serine proteinase inhibitors in leaf extracts from fifteen species of leguminous trees of the Amazon forest. The species studied were Caesalpinia echinata, C. ferrea, Cedrelinga cateniformis, Copaifera multijuga, Dinizia excelsa, Enterolobium contortisiliquum, E. maximum, E. schomburgkii, Leucaena leucocephala, Ormosia paraensis, Parkia multijuga, P. pendula, P. platycephala, Swartzia corrugata and S. polyphylla. Leaves were collected, dried at 30ºC for 48 h, crushed and subjected to extraction with NaCl (0.15 M, 10 percent w/v), resulting in the total extract. Tests were performed to determine the concentration of proteins and to detect of inhibitory activity against bovine trypsin and chymotrypsin. The content of crude and soluble protein in leaf extracts varied from 7.9 to 31.2 percent and 1.3 to 14.8 percent, respectively. The inhibitory activity on trypsin and chymotrypsin was observed in all leaf extracts. However, in extracts of E. maximum, L. leucocephala, P. pendula, S. corrugata and S. polyphylla, the inhibition was greater on trypsin, while extract of P. multijuga was more effective against chymotrypsin. We conclude that leaf extracts of leguminous trees have serine proteinase inhibitors and show potential biotecnological applications.
Assuntos
Quimotripsina , Tripsina , ProteínasResumo
Los estudios de requerimientos nutricionales son de gran importancia para identificar aquellos más importantes en el desarrollo fisiológico y crecimiento de plántulas. Con el objetivo de evaluar las exigencias nutricionales y los efectos de la omisión de macronutrientes en el crecimiento de plántulas de Aniba rosaeodora; se realizó un experimento en el vivero del INPA-Amazonas-Brasil teniendo como substrato un suelo Podozolico Rojo de baja disponibilidad de nutrientes. Se utilizaron 8 tratamientos bajo la técnica del nutriente faltante: Control (Suelo con macronutrientes), Suelo natural, y la omisión de un macronutriente por vez (-N, -P, -K, -Ca, -Mg, -S). Se evaluaron las siguientes características: tasa de crecimiento relativo (TCR), Tasa de asimilación neta (TAN), peso de la materia seca de la parte aérea (MSPA) y de las raíces (MSR), contenido de nutrientes en las hojas, concluyendo que el N, Mg y Ca, demostraron ser limitantes al crecimiento en suelo con pequeña disponibilidad; Las plántulas de A. rosaeodora presentaron un bajo requerimiento nutricional para el P, K y S. La omisión de Ca y N perjudica TCR de la especie. Los elementos más importantes para la MSPA fueron el Ca y el Mg; actuando el Mg más en el área foliar; por otro lado la omisión de azufre favorece la absorción de macronutrientes (N, P, K, Ca, Mg).
Studies of nutritional requirements are of great importance for identifying the most important nutrients in physiologic development and seedling growth. A greenhouse pot experiment was conducted at INPA to evaluate the mineral nutritional demands and the effects of macronutrient omission in the plant growth of Aniba rosaeodora Ducke. The following treatments were used: Complete (fertilization with N, P, K, Ca, Mg, S, B and Zn), Standard (nature soil), Complete without N, Complete without P, Complete without K, Complete without Ca, Complete without Mg, and Complete without S. An Ultisoil with low nutrient availability was used as a substratum. The following characteristics were evaluated, relative growth rate (RGR), net assimilation rate (NAR), plant height, diameter, dry matter production of the aerial part (DMPAP) and amount of nutrient in the dry matter of leaves. We concluded from the results that: low availability of N, Ca and Mg constraints the growth of the Aniba rosaeodora plants. Seedlings of A. rosaeodora required little P, K and S. The omission of Ca and N harmed the RGR of the species. The most important elements for DMPAP were Ca and Mg; the Mg acting more in the leaf area; on the other hand, the omission of sulfur favored the macronutrient absorption (N, P, K, Ca, Mg).