Cynanchum Otophyllum Schneid Research Articles

Production of ρ-Hydroxyacetophenone by Engineered Escherichia coli Heterologously Expressing 1-(4-Hydroxyphenyl)-Ethanol Dehydrogenase.

ρ-Hydroxyacetophenone is an important and versatile compound that has been widely used in medicine, cosmetics, new materials, and other fields. At present, there are two ways to obtain ρ-hydroxyacetophenone. One is to extract it from plants, such as Artemisia capillaris Thunb and Cynanchum otophyllum Schneid, and the other is to synthesize it by using chemical methods. Of these two methods, the second is the main one, although it has problems, such as flammable and explosive reagents, difficult separation of by-products, and harsh reaction conditions. To solve these issues, we adopted genetic engineering in this study to construct engineered Escherichia coli containing Hped gene or EbA309 gene. Whole-cell biotransformation was conducted under the same conditions to select the engineered E. coli with the higher activity. Orthogonal tests were conducted to determine the optimal biotransformation condition of the engineered E. coli. The results showed that the optimal condition was as follows: substrate concentration of 40 mmol/l, IPTG concentration of 0.1 mmol/l, an induction temperature of 25°C, and a transformation temperature of 35°C. Under this condition, the effects of transformation time on the ρ-hydroxyacetophenone concentration and cell growth were further studied. We found that as the transformation time extended, the ρ-hydroxyacetophenone concentration showed a gradually increasing trend. However, when the ρ-hydroxyacetophenone concentration increased to 1583.19 ± 44.34 mg/l in 24 h, cell growth was inhibited and then entered a plateau. In this research, we realized the synthesis of ρ-hydroxyacetophenone by biotransformation, and our findings lay a preliminary foundation for further improving and developing this method.

Selective and sensitive sensing of mercuric ions by natural compound qingyangshengenin

Mercuric ion (Hg2+) is acknowledged as one of the most dangerous contaminants, originating from a range of natural sources and industrial wastes. Hence, it is very important to design and develop highly selective and sensitive probes for the quick detection of Hg2+ in aquatic environments. In view of this, in the presented study a biocompatible C21-steroidal aglycone, qingyangshengenin (1), has been isolated from 95% ethanol extracts of the roots of Cynanchum otophyllum Schneid and characterized by NMR spectroscopy and mass spectrometry. The obtained natural product had been used as photoluminescent sensor for selective and sensitive detection of mercuric cation with limit of detection of 1.61 ppm and KSV value of 7.46 × 102 M−1. Also, interference experiments revealed that 1 can selectively detect Hg2+ ion in presence of other metal cations. Further, theoretical calculations have been done to assess the reason for selectivity of this steroid against the mercuric ion. The integrated experimental and theoretical studies reveals that the plausible reason for the selectively and sensitivity of qingyangshengenin to detect Hg2+ was accredited to the better interaction between Hg2+ and qingyangshengenin.

Characterization and milk coagulating properties of Cynanchum otophyllum Schneid. proteases

The herbaceous plant Cynanchum otophyllum Schneid. is widely used as a milk coagulant to make a Chinese traditional milk product, milk cake. However, the milk-clotting compounds and their mechanism remain unclear. In this study, crude proteases were extracted from the dried leaves of Cynanchum otophyllum Schneid. using citric acid-phosphate buffer and then partially purified by weak anion exchange chromatography. Two proteases, QA and QC, with molecular weights of 14 and 27 kDa, respectively, were shown to exhibit milk-clotting activity. A study of the effects of pH and temperature on the milk-clotting activity and proteolytic activity of the proteases showed that they exhibited good pH stability from pH 5.5 to 7.5 and good thermal stability at temperatures from 50 to 70°C. The QA and QC were the cysteine proteases, able to hydrolyze β-casein and κ-casein completely, and α-casein partially. The cleavage site on κ-casein determined by Orbitrap (Thermo Fisher Scientific, San Jose, CA) analysis showed that QA and QC could cleave κ-casein at Ser132-Thr133. Overall, the results suggest that the Cynanchum otophyllum Schneid. proteases are a promising milk-clotting enzyme that could be used for manufacturing milk cake and cheese.

Protective Effects of Otophylloside N on Pentylenetetrazol-Induced Neuronal Injury In vitro and In vivo.

Approximately 30% of epileptic patients worldwide are medically unable to control their seizures. In addition, repeated epileptic seizures generally lead to neural damage. Pentylenetetrazol (PTZ) is a clinical circulatory and respiratory stimulant that is experimentally used to mimic epileptic convulsion in epilepsy research. Here, we systematically explore the neuroprotective effects of a pure compound isolated from Cynanchum otophyllum Schneid (Qingyangshen), Otophylloside N (OtoN), against PTZ-induced neuronal injury. We used three models: in vitro primary cortical neurons, in vivo mice, and in vivo zebrafish. Our results revealed that OtoN treatment may attenuate PTZ-induced morphology changes, cell death, LDH efflux in embryonic neuronal cells of C57BL/6J mice, and convulsive behavior in zebrafish. Additionally, our Western blot and RT-PCR results demonstrated that OtoN may attenuate PTZ-induced apoptosis and neuronal activation in neuronal cells, mice, and zebrafish. OtoN may reduce PTZ-induced cleavage of poly ADP-ribose polymerase and upregulation of the Bax/Bcl-2 ratio and decrease the expression level of c-Fos. This study is the first investigation of the neuroprotective effects of OtoN, which might be developed as a novel antiepileptic drug.

Cytotoxicity of pregnane glycosides of Cynanchum otophyllum

Fourteen new pregnane glycosides, including nine caudatin glycosides (1–9), three qinyangshengenin glycosides (10–12), one kidjoranin glycosides (13) and one gagaminin glycosides (14), along with twelve known analogs (15–26) were isolated from roots of Cynanchum otophyllum Schneid. Their structures were deduced by detailed analysis of 1D and 2D NMR spectra, as well as HRESIMS. In this study, all pregnane glycosides obtained (1–26) were evaluated for their cytotoxic activities using three cancer cell lines (HepG2, Hela, U251). As results, except 6 and 10, other twenty-four pregnane glycosides showed cytotoxicities at different degrees against three cell lines.

The Lifespan-Promoting Effect of Otophylloside B in Caenorhabditis elegans.

Aging is the major risk factor for many human diseases and degeneration. Thus, clinically effective medicine could delay the process of aging and aging-related diseases are desperately wanted. In traditional Chinese medicine (TCM), some were claimed to slow down aging. Qingyangshen (Cynanchum otophyllum schneid) is such a TCM. Here, we assayed the longevity effect of compound Otophylloside B (Ot B), a C-21 steroidal glycoside isolated from Qingyangshen, in Caenorhabditis elegans, which is a popular model for aging research. Our results showed that Ot B could modestly extend the lifespan of C. elegans, delay the age-related decline of body movement and improve the stress resistance. Further investigating the molecular mechanism of lifespan extension effect revealed that Ot B could activate the FOXO transcription factor DAF-16. Ot B could not further extend the lifespan of long-lived mutant of insulin/IGF-1-like receptor (daf-2). In addition, Ot B also requires SIR-2.1 and CLK-1 which is an enzyme in ubiquinone synthesis, for lifespan extension.Electronic supplementary materialThe online version of this article (doi:10.1007/s13659-015-0064-4) contains supplementary material, which is available to authorized users.

Two new steroidal glycosides from Cynanchum otophyllum Schneid

Two new C21 steroidal glycosides were isolated from Cynanchum otophyllum Schneid. Their structures were elucidated as qinyangshengenin-3-O-β-d-digitoxopyranoside (1) and rostratamine-3-O-β-d-cymaropyranosyl-(1 → 4)-β-d-digitoxopyranoside (2) on the basis of chemical and spectroscopic methods, including 1D and 2D NMR experiments.

Four new C21 steroidal glycosides from Cynanchum otophyllum Schneid

Four new C21 steroidal glycosides, named otophylloside T (2), U (3), V (4) and W (10), together with six known compounds including beishouwubenzophenone (1), the enzymatic hydrolysate of wallicoside (5), Otophylloside M (6), Cynanauriculoside E (7), Wallicoside (8) and Cynauricuoside C (9), were isolated from the roots of Cynanchum otophyllum Schneid. The structures of the four new C21 steroidal glycosides were elucidated as qingyangshengenin-3-O-β-d-thevetopyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-digitoxopyranoside (2), qingyangshengenin-3-O-β-d-thevetopyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-cymaropyranoside (3), caudatin-3-O-β-d-glucopyranosyl-(1→4)-β-d-oleandropyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-digitoxopyranoside (4) and caudatin-3-O-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-β-d-oleandropyranosyl-(1→4)-β-d-oleandropyranosyl-(1→4)-β-d-cymaropyranosyl-(1→4)-β-d-cymaropyranoside (10) by extensive spectroscopic evidence.

Pregnane Glycosides from the Root of Cynanchum otophyllum

Five new pregnane glycosides (1 – 5) were isolated from Cynanchum otophyllum Schneid, a folk medicinal plant known as Qingyangshen, endemic to the Yunnan Province of China.The structures were elucidated by NMR experiments. Compounds2 and 4 exhibited cytotoxic activity against HL-60 cells with IC50 values of 36 and 48µM, respectively.

Isolation and Structural Study on Carbohydrates from Cynanchum otophyllum and Cynanchum paniculatum

Three new carbohydrates were isolated from the acidic hydrolysis part of the ethyl acetate extract of Cynanchum otophyllum Schneid (Asclepiadaceae) and one new carbohydrate from the ethyl acetate extract of Cynanchum paniculatum Kitagawa. Their structures were determined as methyl 2,6-dideoxy-3-O-methyl-α-D-arabino-hexopyranosyl-(1 → 4)-2,6-deoxy-3-O-methyl-β-D-arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-D-arabino-hexopyranoside (1), ethyl 2,6-dideoxy-3-O-methyl-β-D-ribo-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-l-lyxo-hexopyranoside (2), met hyl 2,6-dideoxy-3-O-methyl-α-l-ribo-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-β-D-lyxo-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-D-arabino-hexopyranoside (3), and 2,6-dideoxy-3-O-methyl-β-D-ribo-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α-d-arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3-O-methyl-α -d-arabino-hexopyranose (4), respectively, by spectral methods.

Antifungal agent and other constituents from Cynanchum otophyllum

Seven constituents were isolated from the ethyl acetate extract of the rhizome of Cynanchum otophyllum Schneid (Asclepiadaceae). Their structures were determined as 1-(4-methoxy-3-(6-methoxy-3-acetylphenylperoxy)phenyl)ethanone (1), 1-(3-hydroxy-7-acetylnaphthalen-2-yl)ethanone (2), 1-(3,4-dihydroxyphenyl)ethanone (3), 1-(2,4-dihydroxyphenyl)ethanone (4), 1-(3-(3,6-dihydroxy-2-methylbenzoyl)-2,4-dihydroxyphenyl)ethanone (beishouwubenzophenone) (5), N,N-dimethylethanamine (6), and 2-oxo-2-phenylacetic acid (7), respectively, by spectral methods. Among them, 1 and 2 were new compounds; 1 had antifungal activity.

C 21 steroidal glycosides of seven sugar residues from Cynanchum otophyllum

Two new C 21-steroidal glycosides having hepta-saccharide residue were isolated from the rhizome of Cynanchum otophyllum Schneid. Their structures were determined to be caudatin 3- O-α- l-cymaropyranosyl-(1 → 4)-α- d-oleandropyranosyl-(1 → 4)-α- l-cymaropyranosyl-(1 → 4)-β- d-glucopyranosyl-(1 → 4)-α- d-oleandropyranosyl-(1 → 4)-β- d-oleandropyranosyl-(1 → 4)-β- d-diginopyranoside ( 1), and caudatin 3- O-β- d-cymaropyranosyl-(1 → 4)-α- d-oleandropyranosyl-(1 → 4)-α- l-cymaropyranosyl-(1 → 4)-β- d-glucopyranosyl-(1 → 4)-β- d-oleandropyranosyl-(1 → 4)-β- d-cymaropyranosyl-(1 → 4)-β- d-diginopyranoside ( 2) by spectral methods, respectively.

Carbohydrates from Cynanchum otophyllum

Four new carbohydrates were isolated from the acidic hydrolysis part of the ethyl acetate extract of Cynanchum otophyllum Schneid (Asclepiadaceae). Their structures were determined as methyl 2,6-dideoxy-3- O-methyl-β- d- arabino-hexopyranosyl-(1 → 4)-6-deoxy-3- O-methyl-β- d -ribo-hexopyranosyl-(1 → 4)-6-deoxy-3- O-methyl-α- l- ribo-hexopyranoside ( 1), methyl 6-deoxy-1,3-di- O-methyl-β- d- ribo-hexosyl-(1 → 4)-2,6-dideoxy-3- O-methyl-α- d- arabino-hexopyranoside ( 2), methyl 2,6-dideoxy-3- O-methyl-β- d- arabino-hexopyranosyl-(1 → 4)-6-deoxy-3- O-methyl-α- l- ribo-hexopyranoside ( 3), and 2,6-dideoxy-3- O-methyl-β- d- arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3- O-methyl-α- d -arabino-hexopyranosyl-(1 → 4)-2,6-dideoxy-3- O-methyl-β- d- lyxo-hexopyranose ( 4), respectively, by spectral methods.

Two new antiepilepsy compounds--otophyllosides A and B.

Two new C21 steroidal constituents, named otophylloside A(IV) and otophylloside B(V), have been isolated from the roots of Cynanchum otophyllum Schneid, whose structures have been analysed in this paper by using X-ray crystallography and spectrometric data (UV, IR, 1H- and 13C-NMR, MS) and chemical reaction. They were found to be active against epilepsy, IV and V can protect rats from audiogenic seizures (AS) and its ED50 = 10.20 mg/kg.