High-nitrogen fertilizer alleviated adverse effects of drought stress on the growth and photosynthetic characteristics of Hosta 'Guacamole'.

BACKGROUND: Several plants are facing drought stress due to climate change in recent years. In this study, we aimed to explore the effect of varying watering frequency on the growth and photosynthetic characteristics of Hosta 'Guacamole'. Moreover, we investigated the effect of high-nitrogen and -potassium fertilizers on alleviating the impacts of drought stress on the morphology, photosynthetic characteristics, chlorophyll fluorescence, fast chlorophyll a fluorescence transient, JIP-test parameters, and enzymatic and non-enzymatic scavenging system for reactive oxygen species (ROS) in this species. RESULTS: Leaf senescence, decreased chlorophyll contents, limited leaf area, and reduced photosynthetic characteristics and oxygen-evolving complex (OEC) activity were observed in Hosta 'Guacamole' under drought stress. However, high-nitrogen fertilizer (30-10-10) could efficiently alleviate and prevent the adverse effects of drought stress. High-nitrogen fertilizer significantly increased chlorophyll contents, which was higher by 106% than drought stress. Additionally, high-nitrogen fertilizer significantly improved net photosynthetic rate and water use efficiency, which were higher by 467% and 2900% than those under drought stress. It attributes that high-nitrogen fertilizer could reduce transpiration rate of leaf cells and stomatal opening size in drought stress. On the other hand, high-nitrogen fertilizer enhanced actual photochemical efficiency of PS II and photochemical quenching coefficient, and actual photochemical efficiency of PS II significantly higher by 177% than that under drought stress. Furthermore, high-nitrogen fertilizer significantly activated OEC and ascorbate peroxidase activities, and enhanced the performance of photosystem II and photosynthetic capacity compared with high-potassium fertilizers (15-10-30). CONCLUSIONS: High-nitrogen fertilizer (30-10-10) could efficiently alleviate the adverse effects of drought stress in Hosta 'Guacamole' via enhancing OEC activity and photosynthetic performance and stimulating enzymatic ROS scavenging system.

Amelioration of chronic prostatitis by fractions of Mongolian medicine Hosta plantaginea flowers via inhibition of NF-κB, MAPKs, JAK-STAT, and PI3K-Akt signaling pathways in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Hosta plantaginea (Lam.) Aschers flower is an important Mongolian medicine beneficial in the treatment of chronic prostatitis (CP) in the absence of scientific evidence. AIM OF THE STUDY: The aim of this study was to reveal the therapeutical effects and potential mechanisms of H. plantaginea flowers extract (HP) and its different polarity fractions (HPA∼D) on autoimmune CP (ACP) model rats. MATERIALS AND METHODS: Sprague-Dawley male rats were randomly assigned to 13 groups (n = 6/group). Except the sham group, all rats were injected with a mixture of prostate antigen and complete Freund's adjuvant on days 0, 7, and 21 to establish ACP model rats. Afterwards, ACP model rats were orally gavaged with HP or HPA∼D (1 and 4 g/kg of raw herbal material) or positive drug (Prostat, 200 mg/kg) daily from day 21 to day 50 for 30 days, while the sham and model groups were treated simultaneously with isopyknic of 0.3% sodium carboxymethyl cellulose. Histopathological analysis, biochemical parameters, and protein expression of prostate tissues were investigated. RESULTS: In comparison with the model group, all fraction groups experienced improved CP effects, including restored body weight, reduced prostate gland edema and prostate index, decreased prostatic leukocytes, increased prostatic lecithin bodies, and alleviated histopathological damage to prostate tissue. Furthermore, all fraction groups markedly inhibited the phosphorylated protein of nuclear factor kappa-B p65 (NF-κB p65), NF-κB inhibitor alpha (IκBα), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (Erk), just another kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), phosphoinositide 3-kinase (PI3K), and protein kinase B (Akt) than the model group. CONCLUSION: All fractions of HP exerted significant anti-CP effects by inhibiting NF-κB, MAPKs, JAK-STAT and PI3K-Akt pathways in ACP model rats. These findings provide scientific evidence that H. plantaginea flowers can be used as a pivotal Mongolian medicine in clinical applications for the treatment of CP.

Hand osteoarthritis is associated with limitations in paid and unpaid work participation and related societal costs: the HOSTAS cohort.

OBJECTIVES: Data on work participation impairment and related societal costs for patients with hand osteoarthritis (OA) are scarce. Therefore, we aimed to investigate the association of hand OA with work limitations and costs of productivity loss in paid and unpaid work. METHODS: We used data from the Hand Osteoarthritis in Secondary Care cohort, including patients with hand OA diagnosed by their treating rheumatologist. Using the validated Health and Labour Questionnaire, we assessed experienced unpaid and paid work restrictions, unpaid work replacement by others and inefficiency and absence during paid work related to hand OA over the last 2 weeks. Societal costs (€) per hour of paid and unpaid work were estimated using Dutch salary data in 2019. RESULTS: 381 patients were included (mean age 61 years, 84% women, 26% high education level, 55% having any comorbidity). Replacement of unpaid work by others due to hand OA was necessary for 171 out of 381 patients (45%). Paid work was reported by 181/381 patients (47%), of whom 13/181 (7%) reported absenteeism, 28/181 (15%) unproductive hours at work and 120/181 (66%) paid work restrictions due to hand OA.Total estimated work-related societal costs per patient with hand OA (381 patients) were €94 (95% CI 59 to 130) per 2 weeks (€2452, 95% CI 1528 to 3377 per year). CONCLUSIONS: Hand OA is associated with impairment in paid and unpaid work participation, which translates into substantial societal costs of lost productivity. These results highlight the importance of adequate hand OA treatment.

Kaempferol 3-O-(2G-glucosylrutinoside)-7-O-glucoside isolated from the flowers of Hosta plantaginea exerts anti-inflammatory activity via suppression of NF-κB, MAPKs and Akt pathways in RAW 264.7 cells.

Kaempferol 3-O-(2G-glucosylrutinoside)-7-O-glucoside (KGG) has isolated from Hosta plantaginea flowers and possessed an inhibitory effect on cyclooxygenase 2 (COX-2), could be effective in inhibiting inflammation. However, the anti-inflammatory activity and mechanism of KGG remain unknown. In this study, for the first time, the anti-inflammatory effect of KGG and its potential molecular mechanisms were explored in cells. KGG had no cytotoxicity at concentrations of 1.25, 2.5, 5, 10, 20, and 40 µM by Cell Counting kit-8 assay in RAW 264.7 cells. Besides, KGG concentration-dependently (1.25, 2.5, and 5 µM) inhibited secretions of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and IL-6 in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Western blot showed that the phosphorylation of nuclear factor kappa-B (NF-κB) p65, inhibitor of NF-κB (IκB), p38 MAPK, c-Jun N-terminal kinases (JNK), extracellular signal-regulated kinase (Erk), and protein kinase B (Akt), together with inducible nitric oxide synthase (iNOS) and COX-2 were significantly attenuated by KGG (1.25, 2.5, and 5 µM) in a concentration-dependent relationship. Meanwhile, KGG remarkably enhanced the protein expression of IκB. Taken together, KGG may be one of bioactive phytochemicals from H. plantaginea flowers, and be an anti-inflammatory agent via inhibiting NF-κB, mitogen-activated protein kinases (MAPKs), and Akt signaling pathways.

Chitinophaga hostae sp. nov., isolated from the rhizosphere soil of Hosta plantaginea.

A Gram-negative, rod-shaped aerobic bacterium designated as strain 2R12T was isolated from the rhizosphere soil of Hosta plantaginea. Phylogenetic analyses based on the 16S rRNA gene revealed that strain 2R12T should be assigned to the genus Chitinophaga with the highest sequence similarity to Chitinophaga arvensicola DSM 3695T (99.1 %) and Chitinophaga ginsengisegetis DSM 18108T (98.6 %). The major fatty acids of strain 2R12T (>10 %) were iso-C15 : 0, C16 :1 ω5c and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, two unidentified aminolipids and five unidentified lipids. The predominant respiratory quinone was MK-7. The genomic DNA G+C content was 46.1 mol%. The average nucleotide identity values of strain 2R12T with C. arvensicola DSM 3695T and C. ginsengisegetis DSM 18108T were 77.9 and 78.8 %, respectively, while in silico DNA-DNA hybridization values for strain 2R12T with these strains were 22.8 and 23.3 %, respectively. Based on comparative analysis of phylogenetic, phylogenomic, phenotypic and chemotaxonomic characteristics, strain 2R12T represents a novel species in the genus Chitinophaga, for which the name Chitinophaga hostae sp. nov. is proposed. The type strain is 2R12T (=ACCC 61757T=JCM 34719T).

Protection by Hosta ventricosa polysaccharides against oxidative damage induced by t-BHP in HepG2 cells via the JNK/Nrf2 pathway.

Hosta ventricosa is a plant that can be used for medicine and diet. It has been proven to have anti-inflammatory, antibacterial and antitumor activities, and one of its main constituents is polysaccharides. However, studies on polysaccharides of Hosta ventricosa are limited, and their physiological activities have not been clarified. Therefore, isolation, purification and characterization of Hosta ventricosa root polysaccharides (HVRPp-1) were performed in this research. Furthermore, the effect of HVRPp-1 on tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in HepG2 cells was investigated in vitro. The results showed that HVRPp-1 is a nonhomogeneous polysaccharide that could protect HepG2 cells from oxidative damage through the C-Jun N-terminal kinase (JNK)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. In conclusion, this research proved the antioxidant mechanism of HVRPp-1 for the first time, providing a reliable theoretical basis for basic research on Hosta ventricosa polysaccharides and the possibility of their application in functional foods.

Anti-inflammatory effects of flavonoids and phenylethanoid glycosides from Hosta plantaginea flowers in LPS-stimulated RAW 264.7 macrophages through inhibition of the NF-κB signaling pathway.

BACKGROUND: The flower of Hosta plantaginea (Lam.) Aschers has traditionally been used in China as an important Mongolian medicine for the treatment of inflammatory diseases with limited scientific evidence. In previous studies, 16 flavonoids and 3 phenylethanoid glycosides (1-19) were isolated from the ethanolic extract of H. plantaginea flowers. Nevertheless, the anti-inflammatory effects of these constituents remain unclear. In the present study, the anti-inflammatory effects of these 19 constituents and their underlying mechanisms were assessed in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. METHODS: The viability of RAW 264.7 macrophages was detected by Cell Counting Kit-8 (CCK-8) assay. Meanwhile, nitric oxide (NO) production was measured by Griess assay, while the secretion of tumor necrosis factor α (TNF-α), prostaglandin E2 (PGE2), interleukin 1ß (IL-1ß) and IL-6 in LPS-induced macrophages was determined by enzyme-linked immunosorbent assay (ELISA). Furthermore, the protein expression of nuclear factor kappa B (NF-κB) p65 and phosphorylated NF-κB p65 was evaluated by Western blot analysis. RESULTS: All constituents effectively suppressed excessive NO production at a concentration of 40 µM with no toxicity to LPS-induced RAW 264.7 macrophages. Among them, five flavonoids (1, 4-6 and 15) and one phenylethanoid glycoside (17) remarkably prevented the overproduction of NO with median inhibitory concentration (IC50) values in the range of 12.20-19.91 µM. Moreover, compounds 1, 4-6, 15 and 17 potently inhibited the secretion of TNF-α, PGE2, IL-1ß and IL-6, and had a prominent inhibitory effect on the down-regulation of the phosphorylated protein level of NF-κB p65. CONCLUSION: Taken together, compounds 1, 4-6, 15 and 17 may be useful in managing inflammatory diseases by blocking the NF-κB signaling pathway and suppressing the overproduction of inflammatory mediators.

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.

Isolation and functional diversification of dihydroflavonol 4-Reductase gene HvDFR from Hosta ventricosa indicate its role in driving anthocyanin accumulation.

Anthocyanins are natural colorants are synthesized in a branch of the flavonoid pathway. Dihydroflavonol-4reductase (DFR) catalyzes dihydroflavonoids into anthocyanins biosynthesis, which is a key regulatory enzyme of anthocyanin biosynthesis in plants. Hosta ventricosa is an ornamental plant with elegant flowers and rich colorful leaves. How the function of HvDFR contributes to the anthocyanins biosynthesis is still unknown. In this study, the DFR homolog was identified from H. ventricosa and sequence analysis showed that HvDFR possessed the conserved NADPH binding and catalytic domains. A phylogenetic analysis showed that HvDFR was close to the clade formed with MaDFR and HoDFR in Asparagaceae. Gene expression analysis revealed that HvDFR was constitutive expressed in all tissues and expressed highly in flower as well as was positively correlated with anthocyanin content. In addition, the subcellular location of HvDFR showed that is in the nucleus and cell membrane. Overexpression of HvDFR in transgenic tobacco lines enhanced the anthocyanins accumulation along with the key genes upregulated, such as F3H, F3'H, ANS, and UFGT. Our results indicated a functional activity of the HvDFR, which provide an insight into the regulation of anthocyanins content in H. ventricosa.

Hostaflavone A from Hosta plantaginea (Lam.) Asch. blocked NF-κB/iNOS/COX-2/MAPKs/Akt signaling pathways in LPS-induced RAW 264.7 macrophages.

ETHNOPHARMACOLOGICAL RELEVANCE: Hostaflavone A (HA) is a new flavonoid component isolated from the flower of Hosta plantaginea (Lam.) Asch., which is commonly used as a folk herbal to treat inflammatory diseases in China. Nevertheless, the anti-inflammatory effect of HA remains unknown. AIM OF THE STUDY: This work aimed to evaluate the HA with anti-inflammatory activity and mechanism in RAW 264.7 macrophages activated by lipopolysaccharide (LPS). MATERIALS AND METHODS: Anti-inflammatory effect of HA was evaluated by measuring of cell viability, nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß) and IL-6 levels in RAW 264.7 cells. In parallel, the HA action mechanism of nuclear factor kappa B (NF-κB) p65, inhibitor of NF-κB (IκB), inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), c-Jun N-terminal kinases (JNK), extracellular signal-regulated kinase (Erk), p38, and protein kinase B (Akt) were detected by Western blot analysis. RESULTS: HA has no cytotoxicity at concentrations as high as 40 µM. Besides, HA concentration-dependently clearly suppressed the overproduction of NO, PGE2, TNF-α, IL-1ß and IL-6 in RAW 264.7 cells induced by LPS. In addition, HA remarkably reduced the upregulation of phosphorylated NF-κB p65, phosphorylated IκB, phosphorylated JNK, phosphorylated Erk and phosphorylated p38, together with iNOS and COX-2 protein expressions in a concentration-dependent manner. CONCLUSION: HA blocked the LPS activated inflammation via suppressing NF-κB, iNOS, COX-2, mitogen-activated protein kinases (MAPKs) and Akt pathways in RAW 264.7 cells, and might be a new anti-inflammatory agent.

Joint transcriptomic and metabolomic analysis reveals the mechanism of low-temperature tolerance in Hosta ventricosa.

Hosta ventricosa is a robust ornamental perennial plant that can tolerate low temperatures, and which is widely used in urban landscaping design in Northeast China. However, the mechanism of cold-stress tolerance in this species is unclear. A combination of transcriptomic and metabolomic analysis was used to explore the mechanism of low-temperature tolerance in H. ventricosa. A total of 12 059 differentially expressed genes and 131 differentially expressed metabolites were obtained, which were mainly concentrated in the signal transduction and phenylpropanoid metabolic pathways. In the process of low-temperature signal transduction, possibly by transmitting Ca2+ inside and outside the cell through the ion channels on the three cell membranes of COLD, CNGCs and CRLK, H. ventricosa senses temperature changes and stimulates SCRM to combine with DREB through the MAPK signal pathway and Ca2+ signal sensors such as CBL, thus strengthening its low-temperature resistance. The pathways of phenylpropanoid and flavonoid metabolism represent the main mechanism of low-temperature tolerance in this species. The plant protects itself from low-temperature damage by increasing its content of genistein, scopolentin and scopolin. It is speculated that H. ventricosa can also adjust the content ratio of sinapyl alcohol and coniferyl alcohol and thereby alter the morphological structure of its cell walls and so increase its resistance to low temperatures.When subjected to low-temperature stress, H. ventricosa perceives temperature changes via COLD, CNGCs and CRLK, and protection from low-temperature damage is achieved by an increase in the levels of genistein, scopolentin and scopolin through the pathways of phenylpropanoid biosynthesis and flavonoid biosynthesis.

Effect of chlorophyll biosynthesis-related genes on the leaf color in Hosta (Hosta plantaginea Aschers) and tobacco (Nicotiana tabacum L.).

BACKGROUND: 'Regal Splendour' (Hosta variety) is famous for its multi-color leaves, which are useful resources for exploring chloroplast development and color changes. The expressions of chlorophyll biosynthesis-related genes (HrHEMA, HrPOR and HrCAO) in Hosta have been demonstrated to be associated with leaf color. Herein, we isolated, sequenced, and analyzed HrHEMA, HrPOR and HrCAO genes. Subcellular localization was also performed to determine the location of the corresponding enzymes. After plasmid construction, virus-induced gene silencing (VIGS) was carried out to reduce the expressions of those genes. In addition, HrHEMA-, HrPOR- and HrCAO-overexpressing tobacco plants were made to verify the genes function. Changes of transgenic tobacco were recorded under 2000 lx, 6000 lx and 10,000 lx light intensity. Additionally, the contents of enzyme 5-aminolevulinic acid (5-ALA), porphobilinogen (PBG), chlorophyll a and b (Chla and Chlb), carotenoid (Cxc), superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), proline (Pro) and catalase (CAT) under different light intensities were evaluated. RESULTS: The silencing of HrHEMA, HrPOR and HrCAO genes can induce leaf yellowing and chloroplast structure changes in Hosta. Specifically, leaves of Hosta with HrCAO silencing were the most affected, while those with HrPOR silencing were the least affected. Moreover, all three genes in tobacco were highly expressed, whereas no expression was detected in wild-type (WT). However, the sensitivities of the three genes to different light intensities were different. The highest expression level of HrHEMA and HrPOR was detected under 10,000 lx of illumination, while HrCAO showed the highest expression level under 6000 lx. Lastly, the 5-ALA, Chla, Cxc, SOD, POD, MDA, Pro and CAT contents in different transgenic tobaccos changed significantly under different light intensities. CONCLUSION: The overexpression of these three genes in tobacco enhanced photosynthesis by accumulating chlorophyll content, but the influential level varied under different light intensities. Furthermore, HrHEMA-, HrPOR- and HrCAO- overexpressing in tobacco can enhance the antioxidant capacity of plants to cope with stress under higher light intensity. However, under lower light intensity, the antioxidant capacity was declined in HrHEMA-, HrPOR- and HrCAO- overexpressing tobaccos.

Plantanone D, a new rare methyl-flavonoid from the flowers of Hosta plantaginea with anti-inflammatory and antioxidant activities.

Flowers of Hosta plantaginea have been used for the treatment of inflammation-related diseases in traditional Chinese medicine with limited scientific validation. In the present work, we reported one new rare methyl-flavonoid, plantanone D (1) and one known compound 4-hydroxybenzoic acid (2) from the flowers of H. plantaginea. Their structures were elucidated on the basis of chemical and spectral evidence, as well as by comparison with literature data. To the best of our knowledge, the methyl-flavonoid skeleton have not been reported from any species in Liliaceae family, compound 2 was isolated from the genus Hosta for the first time. The anti-inflammatory activities against cyclooxygenases (COX-1 and COX-2) and antioxidant activities in vitro results revealed that 1 exhibited significant COX-1 inhibition and moderate COX-2 inhibition compared to the reference celecoxib. Additionally, 1 displayed significant antioxidant activity compared to the positive control L-ascorbic acid.

Cytotoxic steroidal glycosides from the underground parts of Hosta ventricosa.

A phytochemical study on the underground parts of Hosta ventricosa yielded one new spirostanol saponin (1), two new furostanol saponins (2 and 3), and one new pregnane glycoside (4), along with three known compounds (5‒7). Their structures were elucidated on the basis of chemical and spectroscopic analysis. All isolated compounds were evaluated for their cytotoxic effects against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480). Compounds 1, 2, and 5‒7 showed cytotoxic activities with IC50 values of 3.21-17.06 µM.

Steroidal glycosides from the underground parts of Hosta ventricosa and their anti-inflammatory activities in mice.

Two new pregnane glycosides, 2α, 3ß-dihydroxy-5α-pregn-16-en-20-one-3-O-{α-L-rhamnopyranosyl-(1→2)-[ß-D-glucopyranosyl-(1→4)]-ß-D-galactopyranoside} (1) and 2α, 3ß-dihydroxy-5α-pregn-16-en-20-one-3-O-{ß-D-glucopyranosyl-(1→2)-[ß-D-xylopyranosyl-(1→3)]-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside}(2), have been isolated along with two known spirostanol saponins from the underground parts of Hosta ventricosa. Their structures were elucidated on the basis of chemical and spectral evidence. The anti-inflammatory activities of these steroidal glycosides were evaluated using a xylene-induced ear edema model. Our results indicated that the compounds exhibited promising anti-inflammatory activities.

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.

Isolation and characterization of flavonoid derivatives with anti-prostate cancer and hepatoprotective activities from the flowers of Hosta plantaginea (Lam.) Aschers.

ETHNOPHARMACOLOGICAL RELEVANCE: The flower of Hosta plantaginea (Lam.) Aschers (Liliaceae) is a traditional medicinal material in Mongolian medicine for treating sore throat, hoarseness, pulmonary fever, and toxic fever in folk. The present work investigated anti-prostate cancer and hepatoprotective activities of flavonoid derivatives from H. plantaginea (Lam.) Aschers. AIM OF THE STUDY: To isolate and identify the chemicals of H. plantaginea (Lam.) Aschers for anti-prostate cancer and hepatoprotective activities. MATERIALS AND METHODS: Active chemicals were isolated and purified from H. plantaginea (Lam.) Aschers by chromatographic methods, and their structures were established on spectroscopic analysis and references. These compounds were evaluated for their anti-prostate cancer activities using the LNCaP prostate cancer cells, and assayed for their hepatoprotective activities on CCl4-induced injury of human L-O2 cells, respectively. RESULTS: Four new flavonol-lignan heterodimers (1-4), together with nine known flavonoid derivatives (5-13) were isolated from this plant for the first time. Among them, some compounds exhibited moderate anti-prostate cancer and hepatoprotective activities. CONCLUSION: Compounds 1, 2, 5, and 6 showed anti-prostate cancer activities using the LNCaP prostate cancer cells with IC50 values of 17.84, 33.26, 54.13, and 81.55 µg/mL, and compounds 3, 4, 8, and 9 exhibited moderate hepatoprotective activities, respectively. A preliminary structure-activity relation was summarized in this paper.

Extraction of Phenolics and Flavonoids from Four Hosta Species Using Reflux and Ultrasound-Assisted Methods with Antioxidant and α-Glucosidase Inhibitory Activities.

The total phenolic and flavonoid contents (TPC and TFC) from the genus Hosta with antioxidant and α-glucosidase inhibitory activities were reported for the first time. Sixteen extracts from the aboveground and underground parts of the four Hosta species, including H. plantaginea, H. ventricosa, H. ensata, and H. albofarinosa, using reflux extraction (RE) and ultrasound-assisted extraction (UAE) techniques have high TPC and TFC with good antioxidant and α-glucosidase inhibitory activities. Furthermore, no significant differences on extraction yields, TPC, and TFC were found between RE and UAE techniques. Additionally, extracts from the aboveground parts of the four Hosta species had higher TPC, TFC, antioxidant, and α-glucosidase inhibitory activities compared to the underground parts by means of RE or UAE techniques. Lastly, the extracts of H. albo-marginata displayed a very remarkable α-glucosidase inhibitory activity compared to the positive control acarbose. The relationships of sixteen extracts of the four Hosta species were analyzed by RE and UAE techniques between extraction yields, TPC, TFC, antioxidant activity, and α-glucosidase inhibitory activity. The present study demonstrated that H. plantaginea, H. ventricosa, H. ensata, and H. albofarinosa could be new sources of natural antioxidants and antidiabetes for pharmaceutical and industrial purposes.

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.

Complete chloroplast genomes of all six Hosta species occurring in Korea: molecular structures, comparative, and phylogenetic analyses.

BACKGROUND: The genus Hosta is a group of economically appreciated perennial herbs consisting of approximately 25 species that is endemic to eastern Asia. Due to considerable morphological variability, the genus has been well recognized as a group with taxonomic problems. Chloroplast is a cytoplasmic organelle with its own genome, which is the most commonly used for phylogenetic and genetic diversity analyses for land plants. To understand the genomic architecture of Hosta chloroplasts and examine the level of nucleotide and size variation, we newly sequenced four (H. clausa, H. jonesii, H. minor, and H. venusta) and analyzed six Hosta species (including the four, H. capitata and H. yingeri) distributed throughout South Korea. RESULTS: The average size of complete chloroplast genomes for the Hosta taxa was 156,642 bp with a maximum size difference of ~ 300 bp. The overall gene content and organization across the six Hosta were nearly identical with a few exceptions. There was a single tRNA gene deletion in H. jonesii and four genes were pseudogenized in three taxa (H. capitata, H. minor, and H. jonesii). We did not find major structural variation, but there were a minor expansion and contractions in IR region for three species (H. capitata, H. minor, and H. venusta). Sequence variations were higher in non-coding regions than in coding regions. Four genic and intergenic regions including two coding genes (psbA and ndhD) exhibited the largest sequence divergence showing potential as phylogenetic markers. We found compositional codon usage bias toward A/T at the third position. The Hosta plastomes had a comparable number of dispersed and tandem repeats (simple sequence repeats) to the ones identified in other angiosperm taxa. The phylogeny of 20 Agavoideae (Asparagaceae) taxa including the six Hosta species inferred from complete plastome data showed well resolved monophyletic clades for closely related taxa with high node supports. CONCLUSIONS: Our study provides detailed information on the chloroplast genome of the Hosta taxa. We identified nucleotide diversity hotspots and characterized types of repeats, which can be used for developing molecular markers applicable in various research area.