Chemical Composition of the Essential Oil of Ligularia hodgsonii and Free Radical Scavenging Activity of the Oil and Crude Extracts

Abstract

The chemical composition of the essential oil from roots and rhizomes of Ligularia hodgsonii was analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). Forty-seven components were identified, representing 77.0% of the total oil. The main constituents were l-(+)-ascorbic acid 2,6dihexadecanoate (15.7%), selina-6-en-4-ol (8.4%) and 9,10-dimethyl-1,2,3,4,5,6,7,8-octahydroanthracene (6.6%). The free radical scavenging activities of the essential oil, aqueous extract, ethanolic extract, and crude polysaccharides of L. hodgsonii, as well as some of their major components, were investigated using DPPH and ABTS assays. The essential oil displayed a lower capacity to quench free radicals than the extracts; the ethanolic and aqueous extracts showed considerably higher antioxidant potential that deserves further study.

Extraction Optimization, Preliminary Characterization and Bioactivities in Vitro of Ligularia hodgsonii Polysaccharides

“…The roots and rhizomes of Ligularia hodgsonii ( L. hodgsonii ) were collected from E’mei Mountain of Sichuan Province, China, and authenticated based on the morphologic appearance, microscopic and physiochemical analyses [ 1 ]. Voucher specimens (LH1701/3) were deposited in School of Pharmaceutical Sciences, Wuhan University.…”

“…The water extract was obtained by refluxing 500 g of powdered herbal materials with distilled water as previously described [ 1 ]. For the extraction of polysaccharides, the powders were firstly defatted with 95% ethanol at 60 °C for 6 times in a reflux apparatus, and then dried to a constant weight.…”

“…The DPPH quenching ability was measured by the reported procedure with a minor modification [ 1 ]. Briefly, 0.3 mL of the aqueous solution of polysaccharides was added to 2.7 mL of 0.07 mM DPPH • methanolic solution; the mixture was shaken vigorously and allowed to stand for 1 h before the absorbance was measured at 516 nm.…”

“…Both otonecine-type PAs and polysaccharides are water-soluble and can be co-administered orally in water extract of LH in Chinese medical practice. Previous studies including ours suggested that the LH polysaccharides might have some antioxidant properties and reverse the PA-induced toxicity in vivo [ 1 , 2 , 13 ]. However, despite of the potentially medicinal values, there is still limited literature on the extraction, characterization and bioactive evaluation of the polysaccharides from LH.…”

“…The roots and rhizomes of Ligularia hodgsonii Hook. (LH), a medicinal plant belonging to the family Asteraceae, have been widely used for the treatment of cough, excessive phlegm, and inflammation in the Chinese herbal medicines [ 1 ]. Recent studies have demonstrated that LH contains essential oils, polysaccharides, phenolic acids, terpenoids and pyrrolizidine alkaloids (PAs) that could contribute to many biological functions of the herb [ 1 , 2 , 3 ].…”