Analysis of water soluble polysaccharides as a potential chemotaxonomic marker for landraces in Bixa orellana.

Annatto tree (Bixa orellana L.) is native to Brazil and is now under cultivation in many parts of world for its reddish orange ‘annatto’ dye. There are three types of landraces in annatto and they are distinguished based on fruit shape i.e., ovate, conical and hemispherical, whose pigment yield differs. Since annatto pigment yield varies with landrace, it is necessary to characterize markers towards the identification of landraces. In this study, we characterized water soluble polysaccharides (WSP) of twigs from three landraces using size-exclusion chromatography (SEC), fourier-transform Infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR) and gas liquid chromatography (GLC) for their potential use as chemotaxonomic markers to distinguish the landraces. GLC analysis on WSP showed hemispherical type contained 38% rhamnose, while conical and ovate types contained 17% and 34% glucose, respectively. Thus, glucose and rhamnose content of WSP could be used to distinguish the three landraces. Further, differences in calculated molecular weight as revealed by SEC (281.8, 151.3 and 79.4 kDa for conical, hemispherical and ovate types, respectively) could also be used to distinguish the three landraces.

Identificação de δ tocotrienol e de ácidos graxos no óleo fixo de urucum (Bixa orellana Linné) / Identification of δ tocotrienols and fatty acids in fixed oil of annatto (Bixa orellana Linné)

Bixa orellana é uma planta nativa do Brasil, conhecida popularmente como urucum. O objetivo desse estudo foi extrair o óleo das sementes de B. orellana e, a partir dele, isolar e identificar o tocotrienol e quantificar seus ácidos graxos. A extração do óleo realizou-se em aparelho Soxhlet utilizando hexano como solvente extrator. O tocotrienol foi isolado por meio de métodos cromatográficos e identificado por espectrometria de ressonância magnética nuclear RMN 1H e RMN 13C. Os ácidos graxos foram quantificados por cromatografia gasosa acoplada ao espectrômetro de massa. Os resultados demonstraram a presença de δ -tocotrienol e, dentre os ácidos graxos, a ocorrência do ácido aracdônico, que até o presente momento não havia sido relatada na espécie em estudo.

Bixa orellana is a native plant of Brazil, popularly known as annatto. The purpose of this study was to isolate the oil from the seeds of B. orellana and from it, identify the antioxidant tocotrienol and quantify its fatty acids. The extraction of the oil was performed in a Soxhlet apparatus using hexane as solvent. The tocotrienol was isolated by chromatographic methods and identified by spectrometric methods NMR 1H and 13C. The fatty acids present in the oil were quantified by gas chromatography coupled with mass spectrometry. Results demonstrated the presence of δ-tocotrienol and among the fatty acids, the arachidonic acid was present, a substance which so far had not been previously reported.