Potent in vivo antifungal activity against powdery mildews of pregnane glycosides from the roots of Cynanchum wilfordii

Chemical constituents from the roots of Cynanchum wilfordii with PCSK9 secretion inhibitory activities

From the Cynanchum wilfordii roots, 32 compounds, including 5 previously undescribed (1, 4-6, 12) and 27 known (2, 3, 7-11, 13-32) compounds, were isolated, and their structures were elucidated using NMR spectroscopic data and MS data aided by ECD calculations or the modified Mosher's reaction. All isolates were tested for their inhibitory effects on proprotein convertase subtilisin/kexin type 9 (PCSK9) secretion. Among the isolates, compound 4, a methyl cholesterol analog, exhibited the most potent effect in reducing PCSK9 secretion, along with PCSK9 downregulation at the mRNA and protein levels via FOXO1/3 upregulation. Moreover, compound 4 attenuated statin-induced PCSK9 expression and enhanced the uptake of DiI-LDL low-density lipoprotein. Thus, compound 4 is suggested to be a potential candidate for controlling cholesterol levels.

Toxicity assessment of 3-O-[6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl]-17β-marsdenin isolated from Gongronema latifolium leaf on selected brain and kidney function indices in mice

The safety of bioactive compounds, especially those isolated from medicinal plants, is a major concern for health authorities, pharmaceutical industries, and the public. Of recent, anti-tumor pregnane glycosides were isolated from Gongronema latifolium leaf, of which the toxicity of one, 3-O-[6-deoxy-3-O-methyl-β-D-allopyranosyl-(1 → 4)-β-D-oleandropyranosyl]-17β-marsdenin (3DMAOM), has not been evaluated. This study, therefore, evaluated the effects of 3DMAOM on selected brain and kidney function indices in mice. Female Swiss albino mice were randomly administered 5% dimethyl sulphoxide and different doses of 3DMAOM (0.5, 1, 2, and 4 mg/kg body weight) for fourteen (14) days, and their blood, brains, and kidneys were collected for biochemical analysis. There was no significant alteration in the activities of alkaline phosphatase (ALP), acetylcholinesterase, creatine kinase, Na+/K+-ATPase, Ca2+/Mg2+-ATPase, and Mg2+-ATPase in the brain of the treated groups compared to control. Also, no significant changes in the activities of ALP, gamma-glutamyltransferase, Na+/K+-ATPase, Ca2+/Mg2+-ATPase, and Mg2+-ATPase in the kidney of the treated groups compared to control. The plasma concentrations of Na+, K+, Cl-, PO43-, creatinine, and urea of mice were not significantly altered at all doses of the 3DMAOM compared to controls. However, the plasma concentration of Ca2+ was significantly reduced (p < 0.05) at all doses of the 3DMAOM, and the plasma concentration of uric acid was significantly reduced (p < 0.05) at 2 mg/kg body weight of the 3DMAOM compared to controls. These findings suggest that 3DMAOM isolated from Gongronema latifolium leaf may not adversely affect brain function but may affect calcium ion homeostasis in subjects.

Two new pregnane glycosides from the root of Cynanchum auriculatum

Two new pregnane glycosides (1 and 2), together with four known ones (3- 6), were isolated from the roots of Cynanchum auriculatum Royle ex Wight (Asclepiadaceae). On the basis of detailed spectroscopic analysis and chemical method, the structures of new compounds were characterized to be metaplexigenin 3-O-β-D-cymaropyranosyl- (1→4)-α-L-diginopyranosyl-(1→4)-β-D-cymaropyranoside (1), metaplexigenin 3-O-α-L-diginopyranosyl-(1→4)-β-D-cymaropyranoside (2). All the isolated compounds (1-6) were tested for their in vitro inhibitory activity against the growth of human colon cancer cell lines HCT-116. Compounds 5 and 6 showed significant cytoxicities with IC50 values of 43.58 µM and 52.21 µM.

A new alkaloid from Thespesia populnea endophytic fungus Penicillium sp. TM-Y1-1

A new alkaloid (3), together with three known compounds, were isolated from the Thespesia populnea endophytic fungus TM-Y1-1. Their structures were elucidated by extensive spectroscopic methods. The absolute configuration of compound 3 was determined for the first time by ECD calculation and DP4+ analysis. All compounds were evaluated for antimicrobial activity. The results showed that compounds 1 and 2 both exhibited moderate inhibitory activity against banana Colletotrichum gloeosporioides with MIC value of 31.25 μg/ml.

12,20-Epoxypregnane Glycosides from the Roots of Oxypetalum caeruleum

The MeOH extract from dried roots of Oxypetalum caeruleum (Apocynaceae, formerly known as Asclepiadaceae) plants yielded twenty new pregnane glycosides, some of which had a new 12,20-epoxy type aglycone. The structures of these compounds were established using NMR, MS spectroscopic analysis and chemical evidence.

C21 Steroidal Glycosides from the Roots of Oxypetalum caeruleum

The MeOH extract from dried roots of Oxypetalum caeruleum (Apocynaceae) plants yielded seventeen new pregnane glycosides, some of which had the acylated-ramanone or -isoramanone type aglycone. The structures of these compounds were established using NMR, MS spectroscopic analysis and chemical evidence.

Cynanchum auriculatum Royle ex Wight., Cynanchum bungei Decne. and Cynanchum wilfordii (Maxim.) Hemsl.: Current Research and Prospects

Cynanchum auriculatum Royle ex Wight. (CA), Cynanchum bungei Decne. (CB) and Cynanchum wilfordii (Maxim.) Hemsl. (CW) are three close species belonging to the Asclepiadaceous family, and their dry roots as the bioactive part have been revealed to exhibit anti-tumor, neuroprotection, organ protection, reducing liver lipid and blood lipid, immunomodulatory, anti-inflammatory, and other activities. Until 2021, phytochemistry investigations have uncovered 232 compounds isolated from three species, which could be classified into C21-steroids, acetophenones, terpenoids, and alkaloids. In this review, the morphology characteristics, species identification, and the relationship of botany, extraction, and the separation of chemical constituents, along with the molecular mechanism and pharmacokinetics of bioactive constituents of three species, are summarized for the first time, and their phytochemistry, pharmacology, and clinical safety are also updated. Moreover, the direction and limitation of current research on three species is also discussed.

Synergistic Antibacterial Activity of an Active Compound Derived from Sedum takesimense against Methicillin-Resistant Staphylococcus aureus and Its Clinical Isolates

There are a growing number of reports of hospital-acquired infections caused by pathogenic bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). Many plant products are now being used as a natural means of exploring antimicrobial agents against different types of human pathogenic bacteria. In this research, we sought to isolate and identify an active molecule from Sedum takesimense that has possible antibacterial activity against various clinical isolates of MRSA. NMR analysis revealed that the structure of the HPLC-purified compound was 1,2,4,6-tetra-O-galloyl-glucose. The minimum inhibitory concentration (MIC) of different extract fractions against numerous pathogenic bacteria was determined, and the actively purified compound has potent antibacterial activity against multidrug-resistant pathogenic bacteria, i.e., MRSA and its clinical isolates. In addition, the combination of the active compound and β-lactam antibiotics (e.g., oxacillin) demonstrated synergistic action against MRSA, with a fractional inhibitory concentration (FIC) index of 0.281. The current research revealed an alternative approach to combating pathogenesis caused by multi-drug resistant bacteria using plant materials. Furthermore, using a combination approach in which the active plant-derived compound is combined with antibiotics has proved to be a successful way of destroying pathogens synergistically.

Anticancer properties of caudatin and related C-21 steroidal glycosides from Cynanchum plants

Numerous C-21 steroidal glycosides have been isolated from Cynanchum plants. Many of them derive from the aglycone caudatin (CDT) which includes a tetracyclic deacylmetaplexigenin unit and an ikemaoyl ester side chain. CDT can be found in diverse traditional medicines, such as Baishouwu radix used to treat gastro-intestinal disorders. The compound has revealed marked anticancer properties, reviewed here. CDT and its mono-glycoside analogue CDMC display antiproliferative activities against different cancer cell lines in vitro and have revealed significant anticancer effects in tumor xenograft models in vivo. Their mechanism of action is multifactorial, implicating several signaling pathways (Wnt/GSK3/β-catenin, TRAIL/DR5/ER and TNFAIP1/NFκB) which contribute to the antiproliferative, antiangiogenic, antimetastatic and proapoptotic effects of the natural products. CDT also modulates DNA replication, is antioxidant and targets some cancer stem cells. CDT and CDMC are interesting anticancer products, while other CDT glycoside derivatives display antiviral and antifungal activities. Altogether, the present review provides a survey of the pharmacological profiles of CDT and derivatives. The lack of knowledge about the molecular targets of CDT currently limits drug development but the natural product, orally active, warrants further pharmacology and toxicology studies.

Nocardioides cynanchi sp. nov., isolated from soil of rhizosphere of Cynanchum wilfordii

A novel actinobacterial strain, SB3-45^T, was isolated from soil of Cynanchum wilfordii rhizosphere, Jaecheon-si, Chungcheongbuk-do, Republic of Korea. Strain SB3-45^T, was Gram-stain-positive, aerobic and coccoid to short rod-shaped bacterium. Growth occurred at 4-37 °C (optimum 28 °C), pH 5-8 (optimum pH 7) and 0-2.5 % NaCl (optimum 0%). Phylogenetic analysis based on 16S rRNA gene sequence showed that strain SB3-45^T belonged to the genus Nocardioides and was closely related to Nocardioides opuntiae OS-21^T (96.2%) and Nocardioides panacihumi Gsoil 616^T (95.9%). ll-DAP as the diamino acid in the peptidoglycan and the menaquinone MK-8(H₄) as the predominant isoprenoid quinone were detected. The polar lipids of strain SB3-45^T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unidentified phospholipid. The major cellular fatty acids (>5%) of strain SB3-45^T were iso-C_16 : 0, C_18 : 1 ω9c and C_17 : 0. Based on phylogenetic, physiological and chemotaxonomic characteristics, strain SB3-45^T represents a novel species of the genus Nocardioides, for which the name Nocardioides cynanchi sp.nov. is proposed. The type strain is SB3-45^T (=KCTC 49133^T=NBRC 114107^T).

Isothiocyanate Derivatives of Glucosinolates as Efficient Natural Fungicides

Fungal pathogens on crops account for losses that exceed US$200 billion annually. At present, chemical fungicides are widely used in the agricultural industry. Many of these products have a detrimental effect on human and animal health and are consequently forbidden postharvest, especially in Europe. Despite efforts to develop natural crop protection, very few have been commercialized. We explored the physicochemical characteristics of (i) glucosinolate derivatives from the present study and previously published papers in the light of their known biological roles and (ii) fungitoxic glucosinolate derivatives compared with natural and chemical fungicides. We found that 13 out of 31 tested natural and semisynthetic isothiocyanates are efficient fungicides against widespread species of plant pathogens alone and in a synergistic manner. Interestingly, physicochemical characteristics of fungitoxic glucosinolate derivatives differ from those showing no activities or known for their insecticidal or insect-attractive properties. The comparison of physicochemical characteristics of natural and semisynthetic fungitoxic glucosinolate derivatives with other fungicides (natural, semisynthetic, and synthetic) revealed that isothiocyanate glucosinolate derivatives clustered with nonglucosinolate derivatives plant fungicides as well as with some synthetic ones. Most of the fungicides show high bioaccumulation potential and lipophilic properties that most likely allow them to go through membranes.

[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Natural Products as Fungicide and Their Role in Crop Protection

Seeking solutions from nature for solving one and all problems is the age-old practice for mankind, and natural products are proved to be the most effective one for keeping up the balance of development as well as the “healthy, wealthy, and well” condition of mother nature. Fungal pathogens are proved to be a common and popular contaminant of agroecosystem that approximately causes 70–80% of total microbial crop loss. To meet the proper global increasing need of food products as a result of population explosion, managing agricultural system in an eco-friendly and profitable manner is the prime target; thus the word “sustainable agriculture” plays it part, and this package is highly effective when coupled with nature-derived fungicidal products that can minimize the event of fungal infections in agrarian ecosystem. Present study enlists the most common and effective natural products that might be of plant or microbial origin, their mode of action, day-by-day development of phytopathogenic resistance against the prevailing fungicides, and also their role in maintenance of sustainability of agricultural practices with special emphasis on their acceptance over the synthetic or chemical one. A large number of bioactive compounds ranging from direct plant (both cryptogams algae and moss and phanerogams)-derived natural extracts, essential oil of aromatic plants, and low-molecular-weight antimicrobial compounds known as phytoalexins to secondary metabolites that are both volatile and nonvolatile organic compounds of microbes (fungal and actinobacterial members) residing inside the host tissue, called endophyte, are widely used as agricultural bioweapons. The rhizospheric partners of plant, mycorrhizae, are also a prime agent of this chemical warfare and protect their green partners from fungal invaders and emphasize the concept of “sustainable agriculture.”

Supplementation with Cynanchum wilfordii radix extract for 8 weeks lowers serum total cholesterol: A controlled, randomized, double-blind clinical trial

This trial aimed to determine the effect of a standardized Cynanchum wilfordii Radix extract (CWE) on the lipid profiles of individuals with elevated total cholesterol (T-Chol) using a double-blind randomized placebo-controlled design. Ninety-six Korean individuals with elevated T-Chol level (200-240 mg/dL) were recruited and randomly allocated to groups that received VasH300 (300 mg CWE/day, n = 32), VasH600 (600 mg CWE/day, n = 32), or a placebo (n = 32) groups. Primary outcomes included T-Chol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, triglyceride, and safety (adverse events, biochemical parameters, and hematological parameters). Data were compared using a one-way analysis of variance followed by Duncan's post-hoc tests (among groups) and paired t tests (within groups). Values for T-Chol and LDL-cholesterol were significantly reduced in the VasH300 and groups (VasH300: 4.0 and 6.4%, respectively; VasH600; 3.8 and 5.8% respectively; both p < .05) compared with the placebo group and were not dose-dependent. VasH300 significantly improved the lipid profiles of individuals with elevated T-Chol without any serious side effects. Daily supplementation with VasH might be an alternative strategy with which to modify cholesterol-related parameters, especially in individuals with elevated T-Chol levels.

Cynanchum bungei Decne and its two related species for "Baishouwu": A review on traditional uses, phytochemistry, and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum bungei Decne. (CB) (Asclepiadaceae) and its two related species Cynanchum auriculatum Royle ex Wight. (CA) and Cynanchum wilfordii (Maxim.) Hemsl. (CW) are well known Chinese herbal medicines known by the name Baishouwu. Among them, CB has long been used for nourishing the kidney and liver, strengthening the bones and muscles, and regulating stomachache. However, to date, no comprehensive review on Baishouwu has been published.

AIM OF THE REVIEW

This review aims to provide a comprehensive summary on traditional uses, phytochemistry, pharmacology, and toxicology of the three herbal components of Baishouwu with the ultimate objective of providing a guide for future scientific and therapeutic potential use of Baishouwu.

MATERIAL AND METHODS

A literature search was undertaken on CB, CA and CW by analyzing the information from scientific databases (SciFinder, Pubmed, Elsevier, Google Scholar, Web of Science, and Baidu Scholar). Information was also gathered from local classic herbal literatures and conference papers on ethnopharmacology and the information provided in this review has been obtained from peer-reviewed papers.

RESULTS

Comparative analysis of literature search indicate that ethnopharmacological use of CB was recorded in China, however, CA and CW have been used in China, Korea and Japan. To date, 151 chemical compounds have been isolated from these species, and the major chemical constituents have been revealed to be acetophenones, C₂₁-steroids, terpenoids, and alkaloids. These compounds and extracts have been proven to exhibit significant pharmacological activities, including anti-tumor, anti-inflammatory, immunomodulatory, hypolipidemic, anti-obesity, hepatoprotective, antifungal, antiviral, anti-depressant, vasodilating and estrogenic activities.

CONCLUSIONS

CB, CA and CW collectively known as Baishouwu are valuable medicinal herbs with multiple pharmacological activities. The traditional use for nourishing liver is closely associated with the hepatoprotective activity. The available literature performs that various of the activity of Baishouwu can be attributed to acetophenones and C₂₁-steroids. It is high time that more efforts should be focused on the underlying mechanisms of their beneficial bioactivities and the structure activity relationship of the constituents, as well as their potential synergistic and antagonistic effects. The proper toxicology evaluation is crucial to guarantee the safety, efficacy, and eligibility for medical use. Further research on the comprehensive evaluation of medicinal quality and the understanding of multi-target network pharmacology of Baishouwu is in great request.

Cytotoxic Pregnane Steroidal Glycosides from Chonemorpha megacalyx

Three new C₂₁ pregnane steroids, chonemorphols A-C (1, 3, and 4), 11 new C₂₁ steroidal glycosides, chonemorphosides A-K (2 and 5-14), and 11 known compounds (15-25) were obtained from the vines and leaves of Chonemorpha megacalyx Pierre. Their structures were established using extensive spectroscopic data. The X-ray crystallographic data of 1 and 3 permitted definition of their absolute configurations. Notably, 1 and 2 possessed an uncommon 6/5/6/5/5-fused steroidal ring system. Compound 7 displayed significant cytotoxicity against several cancer cell lines with IC₅₀ values of 2.0-3.6 μM.

Identification of novel compounds, oleanane- and ursane-type triterpene glycosides, from Trevesia palmata: their biocontrol activity against phytopathogenic fungi

Plants contain a number of bioactive compounds that exhibit antimicrobial activity, which can be recognized as an important source of agrochemicals for plant disease control. As part of our search for new antimicrobial agents from natural sources, we found that a crude methanol extract of Trevesia palmata exhibited a promising antifungal activity against phytopathogenic fungi, such as Magnaporthe oryzae and Botrytis cinerea. Furthermore, based on activity-guided fractionation, we isolated five antifungal compounds from the methanol extract of T. palmata: two new triterpene glycosides (TPGs), TPG1 (hederagenin-3-O-β-_D-glucopyranosyl-(1  → 3)-α-_L-rhamnopyranosyl-(1 → 2)-α-_L-rhamnopyranosyl-(1 → 2)-α-_L-arabinopyranoside) and TPG5 (3-O-α-_L-rhamnopyranosyl asiatic acid), along with three known TPGs (TPG2 [macranthoside A], TPG3 [α-hederin], and TPG4 [ilekudinoside D]). The chemical structures of the TPGs were determined by spectroscopic analyses and by comparison with literature data. An in vitro antifungal bioassay revealed that except for TPG4 (ilekudinoside D; IC₅₀ >256 μg/ml), the other TPGs exhibited strong antifungal activities against the rice blast pathogen M. oryzae with IC₅₀ values ranging from 2–5 μg/ml. In particular, when the plants were treated with compound TPG1 (500 μg/ml), disease control values against rice blast, tomato grey mold, tomato late blight, and wheat leaf rust were 84, 82, 88, and 70%, respectively, compared to the non-treatment control. Considering the in vitro and in vivo antifungal activities of the TPGs and the T. palmata methanol extracts, our results suggest that T. palmata can be a useful source to develop new natural fungicides.

Total C-21 steroidal glycosides, isolated from the root tuber of Cynanchum auriculatum Royle ex Wight, attenuate hydrogen peroxide-induced oxidative injury and inflammation in L02 cells

Oxidative stress plays an important role in the pathology of liver disorders. Total C-21 steroidal glycosides (TCSGs), isolated from the root tuber of Cynanchum auriculatum Royle ex Wight, have been reported to exert numerous effects, including liver protective and antioxidant effects. In order to investigate the potential mechanisms underlying the protective effects of TCSGs on liver function, the present study used the human normal liver cell line, L02, to evaluate the effects of TCSGs on hydrogen peroxide (H₂O₂)-induced oxidative injury and inflammatory responses. The L02 cells were pretreated with various concentrations of TCSGs, followed by exposure to 1.5 mM H₂O₂. Cell viability was determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-di-phenyltetrazolium bromide (MTT) assay. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and nitric oxide (NO) were measured using colorimetric assays. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and the production of malondialdehyde (MDA) were also determined. Intracellular reactive oxygen species (ROS) levels were detected using a fluorescent probe. H₂O₂-induced oxidative toxicity was attenuated following treatment with TCSGs, as indicated by the increase in cell viability, the decreased levels of ALT, AST, LDH, NO, MDA and ROS, and the increased activities of SOD, CAT and GSH-Px. To further explore the possible mechanisms of action of TCSGs, the nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF)-κB pathways were examined. The results revealed that treatment with TCSGs markedly induced Nrf2 nuclear translocation and upregulated the expression of heme oxygenase-1 (HO-1) in the L02 cells damaged by H₂O₂. In addition, pretreatment with TCSGs inhibited the NF-κB signaling pathway by blocking the degradation of the inhibitor of nuclear factor κBα (IκBα), thereby reducing the expression and nuclear translocation of NF-κB, as well as reducing the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2). On the whole, the findings of this study demonstrate that TCSGs can protect L02 cells against H₂O₂-induced oxidative toxicity and inflammatory injury by increasing the expression of Nrf2 and HO-1, mediated by the NF-κB signaling pathway.

Ethnobotany, Phytochemistry and Pharmacological Effects of Plants in Genus Cynanchum Linn. (Asclepiadaceae)

Genus Cynanchum L. belongs to the family Asclepiadaceae, which comprise more than 200 species distributed worldwide. In Chinese medical practice, numerous drugs (such as tablets and powders) containing different parts of plants of this genus are used to treat snake bites, bruises, osteoblasts, rheumatoid arthritis and tumors. A search for original articles published on the cynanchum genus was performed by using several resources, including Flora of China Official Website and various scientific databases, such as PubMed, SciFinder, the Web of Science, Science Direct, and China Knowledge Resource Integrated (CNKI). Advances in the botanical, ethnomedicinal, phytochemical, and pharmacological studies of this genus are reviewed in this paper. Results showed that more than 440 compounds, including C21 steroids, steroidal saponins, alkaloids, flavonoids and terpene, have been isolated and identified from Cynanchum plants up to now. In vivo and in vitro studies have shown that plants possess an array of biological activities, including anti-tumor, neuroprotective and anti-fungal effects. Popular traditional prescription of Cynanchum sp. was also summed up in this paper. However, many Cynanchum species have received little or no attention. Moreover, few reports on the clinical use and toxic effects of Cynanchum sp. are available. Further attention should be focused on the study of these species to gather information on their respective toxicology data and relevant quality-control measures and clinical value of the crude extracts, active compounds, and bioactive metabolites from this genus. Further research on Cynanchum sp. should be conducted, and bioactivity-guided isolation strategies should be emphasized. In addition, systematic studies of the chemical composition of plants should be enhanced.

Preliminary Quality Evaluation and Characterization of Phenolic Constituents in Cynanchi Wilfordii Radix

A new phenolic compound, 2-O-β-laminaribiosyl-4-hydroxyacetophenone (1), was isolated from Cynanchi Wilfordii Radix (CWR, the root of Cynanchum wilfordii Hemsley), along with 10 known aromatic compounds, including cynandione A (2), bungeisides-C (7) and –D (8), p-hydroxyacetophenone (9), 2′,5′-dihydroxyacetophenone (10), and 2′,4′-dihydroxyacetophenone (11). The structure of the new compound (1) was elucidated using spectroscopic methods and chemical methods. The structure of cynandione A (2), including a linkage mode of the biphenyl parts that remained uncertain, was unambiguously confirmed using the 2D ¹³C–¹³C incredible natural abundance double quantum transfer experiment (INADEQUATE) spectrum. Additionally, health issues related to the use of Cynanchi Auriculati Radix (CAR, the root of Cynanchum auriculatum Royle ex Wight) instead of CWR have emerged. Therefore, constituents present in methanolic extracts of commercially available CWRs and CARs were examined using UV-sensitive high-performance liquid chromatography (HPLC), resulting in common detection of three major peaks ascribed to cynandione A (2), p-hydroxyacetophenone (9), and 2′,4′-dihydroxyacetophenone (11). Thus, to distinguish between these ingredients, a thin-layer chromatography (TLC) method, combined with only UV irradiation detection, focusing on wilfosides C1N (12) and K1N (13) as marker compounds characteristic of CAR, was performed. Furthermore, we propose this method as a simple and convenient strategy for the preliminary distinction of CWR and CAR to ensure the quality and safety of their crude drugs.

Plant bioactive molecules bearing glycosides as lead compounds for the treatment of fungal infection: A review

Despite therapeutic advancement in the treatment of fungal infections, morbidity and mortality caused by these infections are still very high. There are approximately 300 fungal species that are infectious and can cause a variety of diseases. At present, several synthetic antifungal drugs are in clinical practice, many of them, however, are vulnerable to multidrug-resistant strains of microbes, and thus compromising the overall treatment outcomes. Glycosides are naturally occurring plant secondary metabolites with important therapeutic potential and clinical utility. The aim of this review was to focus on the antifungal effects of glycosides in preclinical studies with possible mechanism(s) wherein described. Published research show significant susceptibility of different fungi towards phytoglycosides, mediated through multiple mechanisms. Further detailed studies are needed to explain the clinical applications and limitations of these glycosides.

Cynanchum wilfordii Polysaccharides Suppress Dextran Sulfate Sodium-Induced Acute Colitis in Mice and the Production of Inflammatory Mediators from Macrophages

We recently reported the immune-enhancing effects of a high-molecular-weight fraction (HMF) of CW in macrophages and immunosuppressed mice, and this effect was attributed to a crude polysaccharide. As polysaccharides may also have anti-inflammatory functions, we investigated the anti-inflammatory effects and related molecular mechanisms of a crude polysaccharide (HMFO) obtained from HMF of CW in mice with dextran sulfate sodium- (DSS-) induced colitis and in lipopolysaccharide-induced RAW 264.7 macrophages. HMFO ameliorated the pathological characteristics of colitis and significantly reduced production of proinflammatory cytokines in the serum. Histological analysis indicated that HMFO improved the signs of histological damage such as abnormal crypts, crypt loss, and inflammatory cell infiltration induced by DSS. In addition, HMFO inhibited iNOS and COX-2 protein expression, as well as phosphorylated NF-κB p65 levels in the colon tissue of mice with DSS-induced colitis. In macrophages, HMFO inhibited several cytokines and enzymes involved in inflammation such as prostaglandin E₂, nitric oxide, tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, and cyclooxygenase-2 by attenuating nuclear factor-κB (NF-κB) and mitogen-activated protein kinases. HMFO attenuated inflammation both in vitro and in vivo, primarily by inhibiting NF-κB activation. Our findings indicate that HMFO is a promising remedy for treating inflammatory bowel diseases, such as colitis.

Adduct ion-targeted qualitative and quantitative analysis of polyoxypregnanes by ultra-high pressure liquid chromatography coupled with triple quadrupole mass spectrometry

Polyoxypregnane and its glycosides (POPs) are frequently present in plants of Asclepiadaceae family, and have a variety of biological activities. There is a great need to comprehensively profile these phytochemicals and to quantify them for monitoring their contents in the herbs and the biological samples. However, POPs undergo extensive adduct ion formation in ESI-MS, which has posed a challenge for qualitative and quantitative analysis of POPs. In the present study, we took the advantage of such extensive adduct ion formation to investigate the suitability of adduct ion-targeted analysis of POPs. For the qualitative analysis, we firstly demonstrated that the sodium and ammonium adduct ion-targeted product ion scans (PIS) provided adequate MS/MS fragmentations for structural characterization of POPs. Aided with precursor ion (PI) scans, which showed high selectivity and sensitivity and improved peak assignment confidence in conjunction with full scan (FS), the informative adduct ion-targeted PIS enabled rapid POPs profiling. For the quantification, we used formic acid rather than ammonium acetate as an additive in the mobile phase to avoid simultaneous formation of sodium and ammonium adduct ions, and greatly improved reproducibility of MS response of POPs. By monitoring the solely formed sodium adduct ions [M+Na]⁺, a method for simultaneous quantification of 25 POPs in the dynamic multiple reaction monitoring mode was then developed and validated. Finally, the aforementioned methods were applied to qualitative and quantitative analysis of POPs in the extract of a traditional Chinses medicinal herb, Marsdenia tenacissima (Roxb.) Wight et Arn., and in the plasma obtained from the rats treated with this herb. The results demonstrated that adduct ion formation could be optimized for the qualitative and quantitative analysis of POPs, and our developed PI/FS-PIS scanning and sole [M+Na]⁺ ion monitoring significantly improved the analysis of POPs in both herbal and biological samples. This study also provides implications for the analysis of other compounds which undergo extensive adduct ion formation in ESI-MS.

Immune-Enhancing Effects of a High Molecular Weight Fraction of Cynanchum wilfordii Hemsley in Macrophages and Immunosuppressed Mice

The objective of this study was to investigate the immune-enhancing activity of a high molecular weight fraction (HMF) of Cynanchum wilfordii in RAW 264.7 macrophages and the cyclophosphamide (CYC)-induced mouse model of immunosuppression. To identify the bioactive substances of HMF, a crude polysaccharide (HMFO) was obtained and treated with sodium periodate (an oxidation agent) or digested with protease. In macrophages, HMF treatment enhanced the production of nitric oxide (NO) and cytokines (tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interleukin 1β (IL-1β)), as well as phagocytic ability. In CYC-immunosuppressed mice, HMF improved relative spleen and thymus weights, natural killer (NK) cell activity, and splenic lymphocyte proliferation. These increases in NO and cytokines were mediated by up-regulation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Periodate treatment, but not protease treatment, decreased the immune-enhancing activity of HMFO, suggesting that polysaccharides are the active ingredients in C. wilfordii extract.

Identification and Evaluation of Antiepileptic Activity of C21 Steroidal Glycosides from the Roots of Cynanchum wilfordii

Nine new C21 steroidal glycosides, named cynawilfosides A-I (1-9), along with 12 known compounds were isolated from the roots of Cynanchum wilfordii. The structures of the new compounds were elucidated by spectroscopic analysis and chemical methods. The five major components, cynawilfoside A (1), cynauricoside A (11), wilfoside C1N (16), wilfoside K1N (17), and cyanoauriculoside G (18), exhibited significant protection activity in a maximal electroshock (MES)-induced mouse seizure model with ED50 values of 48.5, 95.3, 124.1, 72.3, and 88.1 mg/kg, respectively.

An ethanol root extract of Cynanchum wilfordii containing acetophenones suppresses the expression of VCAM-1 and ICAM-1 in TNF-α-stimulated human aortic smooth muscle cells through the NF-κB pathway

The root of Cynanchum wilfordii (C. wilfordii) contains several biologically active compounds which have been used as traditional medicines in Asia. In the present study, we evaluated the anti-inflammatory effects of an ethanol root extract of C. wilfordii (CWE) on tumor necrosis factor (TNF)-α-stimulated human aortic smooth muscle cells (HASMCs). The inhibitory effects of CWE on vascular cell adhesion molecule (VCAM)-1 expression under an optimum extraction condition were examined. CWE suppressed the expression of VCAM-1 and ICAM-1 and the adhesion of THP-1 monocytes to the TNF-α-stimulated HASMCs. Consistent with the in vitro observations, CWE inhibited the aortic expression of ICAM-1 and VCAM-1 in atherogenic diet-fed mice. CWE also downregulated the expression of nuclear factor-κB (NF-κB p65) and its uclear translocation in the stimulated HASMCs. In order to identify the active components in CWE, we re-extracted CWE using several solvents, and found that the ethyl acetate fraction was the most effective in suppressing the expression of VCAM-1 and ICAM-1. Four major acetophenones were purified from the ethyl acetate fraction, and two components, p-hydroxyacetophenone and cynandione A, potently inhibited the expression of ICAM-1 and VCAM-1 in the stimulated HASMCs. We assessed and determined the amounts of these two active components from CWE, and our results suggested that the root of C. wilfordii and its two bioactive acetophenones may be used for the prevention and treatment of atherosclerosis and vascular inflammatory diseases.

Pregnane-type steroidal glycosides from Gymnema griffithii Craib

Eight pregnane-type steroidal glycosides substituted with ortho-acetate groups were isolated from the methanolic extract of the pericarp of Gymnema griffithii fruits, and named gymnemogriffithosides A-H. Their structures were determined by spectroscopic analysis (one and two dimensional nuclear magnetic resonance, high resolution electrospray ionization mass spectrometry and attenuated total reflectance-Fourier transformed infrared spectroscopy), while the absolute structure of the steroidal skeleton of one of these was additionally determined using Mosher's method. All compounds were evaluated for their in vitro (i) cytotoxic effects against five human tumor cell lines (BT 474, Chago, Hep-G2, KATO-III and SW620) and (ii) α-glucosidase inhibitory activity.

Antimicrobial activities of novel mannosyl lipids isolated from the biocontrol fungus Simplicillium lamellicola BCP against phytopathogenic bacteria

The antagonistic fungus Simplicillium lamellicola BCP has been developed as a microbial biopesticide that effectively controls the development of various plant diseases caused by both pathogenic bacteria and pathogenic fungi. Antibacterial bioassay-directed fractionation was used to isolate mannosyl lipids from S. lamellicola BCP, and the structures of these compounds were elucidated using spectral analysis and chemical degradation. Three novel mannosyl lipids were characterized and identified as halymecins F and G and (3R,5R)-3-O-β-D-mannosyl-3,5-dihydrodecanoic acid. Massoia lactone and (3R, 5R)-3-hydroxydecan-5-olide were also isolated from S. lamellicola BCP. The three novel compounds inhibited the growth of the majority of phytopathogenic bacteria that were tested, and halymecin F displayed the strongest antibacterial activity. Agrobacterium tumefaciens was the most sensitive to the three novel compounds, with IC₅₀ values ranging from 1.58 to 24.8 μg/mL. The ethyl acetate extract of the fermentation broth from the antagonistic fungus effectively reduced the bacterial wilt caused by Ralstonia solanacearum on tomato seedlings. These results indicate that S. lamellicola BCP suppresses the development of plant bacterial diseases through the production of antibacterial metabolites.

Effects of the Cynanchum wilfordii Ethanol Extract on the Serum Lipid Profile in Hypercholesterolemic Rats

The purpose of this study was to investigate the effects of the ethanol extract of Cynanchum wilfordii (ECW) on the blood lipid profile of hypercholesterolemic rats. Thirty 7-week-old male Sprague-Dawley rats were allowed free access to either a normal diet (AIN-93 diet), or 1% high-cholesterol diet with or without 0.5% or 1% ECW for 5 weeks. After sacrifice, the rat serum lipid profile was analyzed. The diets containing ECW decreased body weight gains compared to the normal diet. Serum HDL-cholesterol levels of ECW-fed groups were significantly increased in the hypercholesterolemic groups and normal groups (P<0.05). When 1% ECW was fed to the normal group, total cholesterol level was increased. Moreover, treatment of ECW in hypercholesterolemic groups yielded a dose-dependent and highly significant decrease in the atherogenic index as compared to the control. These results suggest that intake of Cynanchum wilfordii may help reduce the risks of hypercholesterolemia by increasing blood HDL-cholesterol and lowering the atherogenic index.

Effect of Gallotannins Derived from Sedum takesimense on Tomato Bacterial Wilt

In the process of searching antibacterial agents from plants, we discovered that the methanol extract of Sedum takesimense showed potent antibacterial activity against Ralstonia solanacearum in vitro and in vivo. Eight antibacterial gallotannins were isolated from the aerial parts of S. takesimense and identified as gallic acid, methyl gallate, 4,6-di-O-galloylarbutin, 2,6-di-O-galloylarbutin, 2,4,6-tri-O-galloyl-glucose, 1,3,4,6-tetra-O-galloyl-β-glucose, 1,2,4,6-tetra-O-galloyl-β-glucose, and 1,2,3,6-tetra-O-galloyl-β-glucose based on electrospray ionization mass spectrometry and proton nuclear magnetic resonance spectroscopy. These gallotannins displayed broad-spectrum activity against various plant-pathogenic bacteria, and the strongest in vitro antibacterial activities of these gallotannins were against R. solanacearum minimum inhibitory concentration = 0.02 to 0.10 g/liter). Among these gallotannins, methyl gallate and 1,2,3,6-tetra-O-galloyl-β-glucose showed the strongest activities. In addition, synergistic or partial synergistic effects were observed in most combinations between major antibacterial compounds. The wettable powder formulation of the S. takesimense crude extract effectively reduced the development of tomato bacterial wilt caused by R. solanacearum under greenhouse conditions for 14 days after infection. This is the first report on the isolation of antibacterial compounds from S. takesimense. These results suggest that the extract from S. takesimense or the isolated gallotannins could be used as natural bactericides for the control of tomato bacterial wilt.

Effects of pregnane glycosides on food intake depend on stimulation of the melanocortin pathway and BDNF in an animal model

Pregnane glycosides appear to modulate food intake by possibly affecting the hypothalamic feeding circuits; however, the mechanisms of the appetite-regulating effect of pregnane glycosides remain obscure. Here, we show that pregnane glycoside-enriched extracts from swamp milkweed Asclepias incarnata at 25-100 mg/kg daily attenuated food intake (up to 47.1 ± 8.5% less than controls) and body weight gain in rats (10% for males and 9% for females, respectively) by activating melanocortin signaling and inhibiting gastric emptying. The major milkweed pregnane glycoside, ikemagenin, exerted its appetite-regulating effect by decreasing levels of agouti-related protein (0.6-fold) but not NPY satiety peptides. Ikemagenin treatment also increased secretion of brain-derived neurotropic factor (BDNF) downstream of melanocortin receptors in the hypothalamus (1.4-fold) and in the C6 rat glioma cell culture in vitro (up to 6-fold). These results support the multimodal effects of pregnane glycosides on feeding regulation, which depends on the activity of the melanocortin signaling pathway and BDNF.