AROMA CHARACTERISTICS OF OSMANTHUS FRAGRANS LEAVES
Journal: Open Journal of Chemical Engineering (OJCE)
Author: Zhiqiang Chu1#, Qiang Jiao2#, Linzuo Teng3#, Ruili Gu3#, Xinya Gao1#, Bin Wu1, Xian Wang1, Ying Zhou1, Fude Shang1, Ximei Li1, Yuanyuan Chen1*, Dangquan Zhang1*
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Osmanthus fragrans, also known as guihua, native to China, is one of the top ten traditional flowers in China. O. fragrans is an ornamental and practical garden tree species with an integrated set of greening, beautification, purification, and perfuming. Recent studies on the development and utilization of O. fragrans’s products have been mainly molecular structure analysis of petal extracts and their medicinal value. There are few studies on the utilization of leaves. This article provides a systematic chemical basis for the high-grade development and utilization of O. fragrans leaves. We describe the component differences and functional characteristics of various solvent extracts, and analyze the law of thermal weight loss and change of surface microstructure of O. fragrans leaves. Osmanthus fragrans leaves are rich in phytol, n-hexadecanoic acid, and squalene in three organic solvent extracts: petroleum ether, ethanol, and benzene/ethanol. Phytol is often used in the manufacture of vitamins, chemicals, emulsifiers, antioxidants, and nutritional supplements. Squalene is a bioactive substance with many physiological functions, such as increasing superoxide dismutase (SOD) activity in vivo, enhancing immunity, and anti-aging and antitumor properties. Among the three extracts, we also found a variety of substances with relatively low content and good medicinal value, which includes antioxidant, anti-inflammatory, radiation damage, anticancer, antibacterial, antihelmintic, antidepressant, and neurological effects, the oil content in the leaves of O. fragrans is also not low. The total content trend of the extract’s petroleum ether, ethanol, and benzene / ethanol is from high to low, and the kinds of extracted substances are also from many to less, indicating that petroleum ether extract has the best development prospect. FTIR further demonstrated that O. fragrans leaves contain esters, phenols, aldehydes, carboxylic acids, and alkenes. In addition, organic solvent extraction did not change components of O. fragrans leaves significantly. Thermogravimetric analysis showed that the thermal weight changes of O. fragrans leaves were divided into four stages, with the rate of mass loss ranging Third stage, fourth stage, second stage, and first stage. At three critical temperature turning points during TG treatment, the mass of O. fragrans leaves changed significantly, which may be caused by pyrolysis of macromolecules into small molecules. Scanning electron microscope observation revealed that the powder of O. fragrans leaves is not suitable for use as absorbent materials, but is more suitable for making gel and chemical pulp.