Determinación de la actividad antioxidante en polifenoles, actividad antiinflamatoria y digestión gastrointestinal in vitro en proteínas de hoja de Ilex Guayusa

Abstract

Ilex guayusa is a bush leave native from ecuadorian jungle. Assay from the vegetal flour obtained from dry leaves showed like principal components: 61 % carbohydrate, 18.2 % proteins and 6.67 % ashes which means that Ilex guayusa leaves, has high protein content compared to other medicinal leaves like indian loto, zarzaparrilla, pesgua and yaca, this medicinal plants conteins on average of 5% of protein and could be interest by pharmaceutical and food industry. On this study Ilex guayusa proteins were insolate by isoelectric method was used to separate the vegetable protein. The highest yield was obtained at pH 3.0 with 5.59 % and 64.57% of protein content in insolate, while the second extraction was effective for pH 4.0 enhancing the yield from 2.98 % to 4.17 % with 34.4 % of protein in the insolate. By SDS-PAGE electrophoresis method the molecular weight were estimated finding 6-60 kDa bands, bidimensional electrophoresis showed isoelectric point situated between 3.0-4.0 pH and 30 kDa molecular weight. In vitro digestibility of Ilex guayusa insolate protein were totally hydrolyzed at pH 3.0 corresponding to juices of gastric phase of digestion. Moreover the polyphenols content from isoelectric protein separation supernatant on different pH were estimated, the highest content (1508, 03 mg of galic acid / 100 g) was finding at pH 5.0. Likewise the anti-inflammatory activity was compared with a commercial anti-inflammatory known as Diclofenaco founding the highest activity (67,89%) on pH 4.5 with lower concentration (500µg/ml). Finally anti-oxidant activity was compared with a commercial antioxidant butilhidroxitoluen (BHT), the activity was evaluated in Ungurahua oil, this vegetable oil is very sensitive to oxidation at compare to palm oil, the guayusa protein showed the highest activity (79.09% y 80.47%) at pH 4.5 with 100 and 1000 µg/ml concentration.Therefor bio-actives peptides from Ilex guayusa protein insolates are interesting to pharmaceutical and food processing industries.