Fragrans Lour Research Articles

Genus Osmanthus Lour. (Oleaceae) and Osmanthus suavis King ex C. B. Clarke new record for the flora of Vietnam

The genus Omanthus Lour. had about 35 species in the world including 5 sections, distributed in tropical and subtropical in South East Asia, America. The genus Osmanthus Lour. was published by Loureiro (1790) with the typus was O. fragrans Lour. In Vietnam, based on Loureiro (1790), F. Gagnepain (1933), P. H. Ho (2003), T. D. Ly (2003) and B. H. Quang (2014) there are 2 species in sections Leiolea, Osmanthus. During studying specimens of this section in the Herbaria, we introduced O. suavis. in section Siphosmanthus, as a new record for flora of Vietnam. This species has distribution in Lao Cai, Thanh Hoa. Species O.suavis. was closed to O. delavayi by Cymes fascicled in leaf axils or terminal, but O. suavis different with O. delavayi, by (leaves petiole 5-7 (10) mm, primary viens 5-8 on each side of midrib and Drupe blue-black, ellipsoid or ovoid, ca. 8 x 5 mm.). vs (leaves petiole 2-3 mm, primary viens 4-5 on each side of midrib, Drupe blue-black, ellipsoid or ovoid, ca. 1-1.5 cm). In this article, we introduce nomenclature, key to species, morphology and illustration, distribution and research specimen of all species in genus Osmanthus Lour. in Vietnam.

Transcriptome sequencing and analysis of sweet osmanthus (Osmanthus fragrans Lour.)

Osmanthus fragrans is a woody, evergreen species of shrubs and small trees that is extensively planted in sub-tropical and temperate climates as an ornamental plant in gardens and for its health benefits. The flower color ranges from ivory to orange to pink among different varieties and even color difference during the whole blossom in the sweet osmanthus. Sweet osmanthus is widely cultivated throughout China and other countries due to its prominent fragrance, colorful flowers, and medicinal properties. However, the scanty genomic resources in the Olea family have greatly hindered further exploration of its genetic mechanism on these economically important traits. In this study, transcriptome sequencing of O. fragrans was performed using the Illumina HighSeqTM2000 sequencing platform. Next generation sequencing (NGS) of the transcriptome of O. fragrans produced 31.7G of clean bases (211,266,818 clean reads) that were assembled into 256,774 transcripts and 117,595 unigenes. Of them, 197 and 237 candidate genes involved in fragrance and pigment biosynthesis respectively were identified based on function annotation. Meanwhile, 1 unnamed protein and 468 functional unknown genes were also identified. Furthermore, mRNA sequencing expression profiling of O. fragrans were compared to previous genes’. In summary, this comprehensive transcriptome dataset allows the identification of genes associated with several major metabolic pathways and provides a useful public information platform for further functional genomic studiesin O. fragrans Lour.

Essential Oil Composition of Osmanthus fragrans Varieties by GC-MS and Heuristic Evolving Latent Projections

The essential oils from two varieties of Osmanthus fragrans have been extracted by steam distillation and analyzed by gas chromatography-mass spectrometry with the help of heuristic evolving latent projections (HELP), an effective chemometric resolution method. The overlapped peak clusters were resolved into pure chromatograms and pure mass spectra with HELP. Identification of the components was by comparison of temperature-programmed retention indices (PTRIs) and by similarity searches in the National Institute of Standards and Technology mass database. Quantitative results were obtained by overall integration of the peaks. The reliability of the qualitative and quantitative results was greatly improved by using HELP and PTRIs. The main components from O. fragrans Lour. var. thunbergii Mak. (TM) and O. fragrans Lour. var. aurantiacus Mak. (AM) were 1,2-epoxy linalool and nonanal, respectively. In total, 52 volatile components in essential oil of TM and 45 in AM were analyzed qualitatively and quantitatively, accounting for 95.67 and 92.28% total contents of the essential oils.