RESUMO
This study analyzes the lipid composition and the oxidative stability of oils of Sapindaceae and Meliaceae seeds. The oil content ranged from 14.7% (Guarea guidonia) to 30.1% (Allophylus puberulus and Paullinia elegans). Ten fatty acids were identified in seed oils. Guarea guidonia seeds accumulated mainly oleic (44.9%) and linoleic (24.1%) acid, whereas the unusual gondoic and paullinic acids were identified in A. puberulus (15.8%; 8.9%) and P. elegans (14.4%; 44.2%), respectively. The oil of P. elegans had the highest oxidative stability (16.2 h.). Tocopherol predominated in A. puberulus (10.4 mg/100 g) and tocotrienol predominated in G. guidonea and P. elegans (2.6 mg/100 g). The vitamers α-tocopherol, γ-tocopherol, and γ-tocotrienol were found in the studied oils. ß-carotene was predominantly detected in the oil of A. puberulus seeds (22.4 µg/g). Guarea guidonia seed oil has a high potential in food due to richness in essential fatty acids. In turn, A. puberulus and P. elegans oils could be suggested for other industrial purposes (e.g., biodiesel, varnishes, paints, soaps, or oleochemicals) due to their content of long-chain fatty acids.
RESUMO
Extratos aquosos da planta medicinal Achillea millefolium contêm macromoléculas de interesse para desenvolver fitodefensivos para a agricultura. Duas frações de mil folhas foram obtidas por ultrafiltração, E1 (contendo moléculas maiores que 30 kDa), e E3 (peptídeos entre 1 e 10 kDa) que inibiram o crescimento das bactérias fitopatogênicas Ralstonia solanacearum, gram-negativa, e Clavibacter michiganensis subsp. michiganensis, gram-positiva, com dependência de concentração. Os valores de concentração inibitória mínima (CIM) para ambos os extratos e bactérias foram baixos, entre 20 e 80µM. A CIM relativa à proteína total evidenciou a presença de macromoléculas muito ativas em E3, embora com baixa concentração proteica. E3 se aplica à prospecção de peptídeos antimicrobianos. Estimar a CIM relativa à quantidade de amostra vegetal valorizou o potencial antimicrobiano natural de E1, que contém alta concentração proteica. E1e E3 se aplicam ao desenvolvimento de fitodefensivos para uso biotecnológico. A ultrafiltração fracionou as amostras de forma nativa, rápida, e com baixo custo; além de dessalinizar, clarificar, purificar, e concentrar E1 e E3. Esse estudo inédito sobre a separômica e a ação antimicrobiana de extratos macromoleculares aquosos de mil folhas sugere que plantas cicatrizantes podem apresentar grande potencial para desenvolver fitodefensivos agrícolas naturais não danosos, à semelhança de medicamentos fitoterápicos.
Aqueous extracts from the medicinal plant Achillea millefolium contain macromolecules of interest to develop agrochemicals for agriculture. Two fractions of "mil folhas" were obtained by ultrafiltration, E1 (containing molecules larger than 30 kDa) and E3 (peptides between 1 and 10 kDa), which inhibited the growth of phytopathogenic bacteria Ralstonia solanacearum, gram-negative, and Clavibacter michiganensis subsp. michiganensis, gram-positive, concentration-dependent. The values of minimum inhibitory concentration (MIC) for both extracts and both bacteria were low, ranging from 20 to 80µM. The MIC relative to total protein evidenced the presence of very active macromolecules in E3, although showing low protein concentration. E3 applies to the prospection of antimicrobial peptides. The estimated MIC relative to the amount of plant sample valued the natural antimicrobial potential of E1, which contains high protein concentration. E1 and E3 can be used in the development of agrochemicals for biotechnological purposes. The ultrafiltration procedure fractionated the samples in a rapid and native way and at a low cost; it also desalted, clarified, concentrated and purified both E1 and E3. This pioneering study on the separomics and on the antimicrobial activity of macromolecular aqueous extracts from "mil folhas" suggests that healing plants have great potential to develop non-harmful agricultural natural agrochemicals, similarly to the available phytotherapic drugs.
