Potential active constituents responsible for treating acute pharyngitis in the flowers of Hosta plantaginea (Lam.) Aschers and their pharmacokinetics.

In Asia, the flower of Hosta plantaginea (Lam.) Aschers (hosta flower) is both an edible food and medicine. The hosta flower is often used as a material for cooking porridge and scented tea and in combination with other plants for alleviating pharyngitis. To clarify the anti-pharyngitis effect of the hosta flower and evaluate its potential active ingredients, an ethanol extract of the hosta flower was prepared and partially purified via chromatography on a column packed with D101 macroporous resin, which was eluted with different concentrations of ethanol. The anti-pharyngitis effect of the crude extract and the various partially purified fractions was examined in an ammonia-induced acute pharyngitis rat model. The 30% ethanol-eluted fraction significantly alleviated the severity of pharyngitis in the rat, as evaluated by changes in the levels of cytokines (IL-1ß, IL-6, and TNF-α) and histological changes in the pharynx tissues. Subsequent HPLC-QTOF/MS (high-performance liquid chromatography coupled with quadrupole-time of flight tandem mass spectrometry) analysis of this fraction revealed kaempferol and its glycosides as the main components. Three of the main components were isolated and identified by 1D NMR. Their pharmacokinetics were studied for the first time by UHPLC-QQQ/MS (ultrahigh-performance liquid chromatography coupled with mass spectrometry). The findings suggested that the 30% ethanol-eluted fraction of the hosta flower extract may be a potential functional food for treating pharyngitis.

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.

Five new compounds from Hosta plantaginea flowers and their anti-inflammatory activities.

Five new compounds hostines A-E (1-5), together with eighteen known compounds (6-23), were obtained from the flowers of Hosta plantaginea (Lam.) Aschers, a traditional folk herbal medicine widely used in Mongolian. The structures of the undescribed compounds were determined by using detailed spectroscopic (1D/2D NMR) and HR-ESI-MS data analysis. The biological evaluation revealed that hostine C (3), hostine D (4), hostine E (5), stellarine (16), and phenethyl-O-ß-d-glucopuranoside (19) possessed the significant anti-inflammatory activities, these compounds significantly inhibited the NO release of RAW 264.7 cells induced by LPS. The possible mechanism of NO inhibition of new bioactive compounds was also investigated using molecular docking, which revealed the interactions of bioactive compounds with the iNOS protein.

[A new antioxidant flavonoid glycoside from flowers of Hosta plantaginea].

Phytochemical investigation of the flowers of Hosta plantaginea led to isolate of one new flavonoid glycoside,plantanone C( 1) by silica gel,Sephadex LH-20,and RP-HPLC column chromatographies. Its structure was extensively determined on basis of HR-ESI-MS and NMR spectroscopic data. Compound 1 exhibited moderate antioxidant activity against DPPH radical scavenging activity,with an IC50 value of 240. 2 µmol·L~(-1).

A new flavonol glycoside from the flowers of Hosta plantaginea with cyclooxygenases-1/2 inhibitory and antioxidant activities.

Hosta plantaginea was a traditional Chinese medicinal plants used to treat inflammatory and painful diseases with partial scientific validation. Solvent extractions followed by repeated chromatographic purification of the H. plantaginea flowers led to the isolation of one new flavonoid glycoside, hostaflavone A (1), together with one related known compound, kaempferol-3-O-sophoroside-7-O-glucoside (2), and their structures were elucidated on the basis of chemical and spectral evidence, as well as by comparison with literature data. Compounds 1 and 2 were evaluated for the anti-inflammatory activites against cyclooxygenases (COX-1 and COX-2) and DPPH free radical-scavenging activities in vitro. The results revealed that 1 and 2 exhibited significant COX-1 inhibition and moderate COX-2 inhibition compared to the reference celecoxib. Additionally, 1 and 2 displayed insignificant antioxidant activities compared to the positive control L-ascorbic acid.

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-ß-d-glucopyranoside (2), together with six known compounds, anti-1-phenylpropane-1,2-diol (3), phenethyl-O-ß-d-glucopyranoside (4), phenethanol-ß-d-gentiobioside (5), phenethyl-O-rutinoside (6), (1S, 3S)-1-methyl-1,2,3,4-tetrahydro-ß-carboline-3-carboxylic acid (7), and (1R, 3S)-1-methyl-1,2,3,4-tetrahydro-ß-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.

New steroidal glycosides from Hosta plantaginea (Lam.) Aschers.

Four new furostanol glycosides were isolated from the flowers of Hosta plantaginea (Lam.) Aschers. On the basis of spectroscopic methods including 1D and 2D NMR experiments, their structures were elucidated as 26-O-ß-d-glucopyranosyl-(25R)-22-O-methyl-5α-furostan-2α,3ß,22ξ,26-tetrol 3-O-α-l-rhamnopyranosyl-(1 â†’ 4)-O-ß-d-xylopyranosyl-(1 â†’ 3)-[O-ß-d-glucopyranosyl-(1 â†’ 2)]-O-ß-d-glucopyranosyl-(1 â†’ 4)-ß-d-galactopyranoside (hostaplantagineoside A, 1), 26-O-ß-d-glucopyranosyl-(25R)-5α-furostan-20(22)-ene-2α,3ß,26-triol-3-O-ß-d-glucopyranosyl-(1 â†’ 2)-[O-ß-d-xylopyranosyl-(1 â†’ 3)]-O-ß-d-glucopyranosyl-(1 â†’ 4)-ß-d-galactopyranoside (hostaplantagineoside B, 2), 26-O-ß-d-glucopyranosyl-(25R)-5α-furostan-22(23)-ene-2α,3ß,20α,26-tetraol-3-O-ß-d-glucopyranosyl-(1 â†’ 2)-[O-ß-d-xylopyranosyl-(1 â†’ 3)]-O-ß-d-glucopyranosyl-(1 â†’ 4)-O-ß-d-galactopyranoside (hostaplantagineoside C, 3), 26-O-ß-d-glucopyranosyl-(25R)-5α-furostan-20(22)-ene-2α,3ß,26-triol-3-O-α-l-rhamnopyranosyl-(1 â†’ 4)-O-ß-d-xylopyranosyl-(1 â†’ 3)-[O-ß-d-glucopyranosyl-(1 â†’ 2)]-O-ß-d-glucopyranosyl-(1 â†’ 4)-ß-d-galactopyranoside (hostaplantagineoside D, 4).

Benzylphenethylamine alkaloids from Hosta plantaginea with inhibitory activity against tobacco mosaic virus and acetylcholinesterase.

Five new benzylphenethylamine alkaloids, hostasine (1), 8-demethoxyhostasine, 8-demethoxy-10-O-methylhostasine, 10-O-methylhostasine, and 9-O-demethyl-7-O-methyllycorenine, along with 12 known compounds, were isolated from Hosta plantaginea by bioassay-guided fractionation. The structures of the new alkaloids were established by means of extensive spectroscopic methods, and the relative configuration of 1 was further confirmed by single-crystal X-ray diffraction. 7-Deoxy-trans-dihydronarciclasine (IC(50) = 1.80 microM), a known alkaloid, showed strong activity against tobacco mosaic virus by the half-leaf method. Some of these alkaloids were also evaluated for their inhibitory activity against acetylcholinesterase. 8-Demethoxy-10-O-methylhostasine was found to possess significant activity, with an IC(50) of 2.32 microM.