A new sesquiterpene lactone from Hosta ensata

Chemical constituents isolated from Hosta ensata and their anti-inflammatory activities

A new phenol derivative, hostaphenol A (1), along with 16 known ones (2-17) were isolated from an ethanolic extract of the whole plants of Hosta ensata F. Maek. Their structures were elucidated by HRMS and NMR data as well as comparison with those reported in literature. The report of the first cyclopeptide and compounds 5, 6, 8, 10, 12-15, and 17 in the Asparagaceae family. Compound 2, as well as compounds 3, 4, 7, 9, 11, and 16 were reported for the first time from the Hosta genus and this plant, respectively. All compounds significantly reduced nitric oxide (NO) production at a concentration of 40 μM with no toxicity in RAW 264.7 cells stimulated by lipopolysaccharide. Among them, compounds 2-5 (40 μM) exerted obvious NO inhibitory activities, and their inhibition rate was exceeded 50%.

Traditional uses, phytochemistry, pharmacology and toxicological aspects of the genus Hosta (Liliaceae): A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Hosta (Liliaceae family) represents an interesting source of natural bio-constituents, and the 50 species of this genus are widespread in the world. Five species have been used as traditional East Asian medicines for treating inflammation and pain-related diseases. However, the available data for this genus have not been comprehensively reviewed regarding their extracts and secondary metabolites.

AIM OF THE STUDY

The present review aims to provide a deeper insight, better awareness and detailed knowledge of traditional uses, phytochemistry, pharmacology along with toxicological aspects of the genus Hosta in the past decades (February 1964 to August 2020). In addition, the relevance among traditional uses, pharmacology and phytochemistry in folk medicines were extensively discussed.

MATERIALS AND METHODS

The relevant information of Hosta species was obtained from several databases. Moreover, the medical books, PhD and MSc dissertations in Chinese were also used to perform this work.

RESULTS

Comprehensive analysis of the afore-mentioned databases, medical books and dissertations confirmed that ethnomedical uses of Hosta genus plants had been recorded in China, Japan, Korea and other countries. To date, only eight species have been studied for chemical constituents, and a total of 200 secondary metabolites (not include essential oil constituents), including steroids, flavonoids, alkaloids, furan derivatives, phenylpropanoids, phenethyl derivatives, terpenoids, aliphatics, and others. The crude extracts and isolated chemical constituents exhibited anti-inflammatory and analgesic, antioxidant, anti-tumor, anti-viral, acetylcholinesterase inhibitory, antimicrobial, anti-chronic prostatitis, and other effects. Moreover, only the n-butanol fraction of H. ventricosa (Salisb.) Stearn roots showed moderate acute toxicity in mice. In addition, the relevance among traditional uses, pharmacology and phytochemistry in folk medicines were extensively discussed.

CONCLUSIONS

Hosta spp. are plants rich in steroids and flavonoids with valuable medicinal properties; though, there are several gaps in understanding the traditional uses in the current available data. More high scientific quality preclinical studies with new methodology are necessary to assess the safety, efficacy and mechanism of these plants.

Chemical Constituents from the Flower of Hosta plantaginea with Cyclooxygenases Inhibition and Antioxidant Activities and Their Chemotaxonomic Significance

Two new phenolic glucosides, hostaflavanone A (1) and anti-1-phenylpropane-1,2-diol-2-O-β-d-glucopyranoside (2), together with six known compounds, anti-1-phenylpropane-1,2-diol (3), phenethyl-O-β-d-glucopyranoside (4), phenethanol-β-d-gentiobioside (5), phenethyl-O-rutinoside (6), (1S, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (7), and (1R, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (8), were isolated from the flower of Hosta plantaginea, and their structures were elucidated by nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectroscopy (HRESIMS), and circular dichroism (CD) analyses. The cyclooxygenases (COX-1 and COX-2) inhibition and antioxidant activities of compounds 1 and 4–6 were investigated, and they showed moderate cyclooxygenases inhibition activities. Moreover, only compound 1 exhibited moderate antioxidant activity, with an IC₅₀ value of 83.2 μM, while 4–6 showed insignificant activity with IC₅₀ values of 282, 257, and 275 μM, respectively. This is the first report of compounds 3 and 5–8 from the Liliaceae family. The chemotaxonomic significance of the isolated compounds was also summarized.

Heterocyclic terpenes: linear furano- and pyrroloterpenoids

This review of furano- and pyrroloterpenoids covers the literature, 180 articles in all, published from January 2006 to December 2013.

Natural sesquiterpenoids

This review covers the isolation, structural determination, synthesis and chemical and microbiological transformations of natural sesquiterpenoids. The literature from January to December 2012 is reviewed, and 471 references are cited.