OBJECTIVETo isolatate and elucidate the antioxidant constituents from acetone extract of Scutellaria rehderiana.

METHODChemical constituents were isolated by several column chromatographies and their structures were elucidated on the basis of standard compounds and spectral analysis.

RESULTFive compounds, oroxylin A, wogonin, baicalein, ganhuangenin, ganhuangemin were isolated from acetone extract of S. rehderiana. Baicalin was obtained from methanol extract of S. rehderiana.

CONCLUSIONGanhuangemin was isolated from the plant for the first time. Baicalein and ganhuangenin have stronger antioxidant activity than that of BHT (butylated hydroxytoluene).

Antioxidants ; chemistry ; isolation & purification ; pharmacology ; Flavanones ; chemistry ; isolation & purification ; pharmacology ; Flavonoids ; chemistry ; isolation & purification ; pharmacology ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry ; Scutellaria ; chemistry

OBJECTIVETo study the chemical constituents of Davidia involucrata var. vilmoriniana.

METHODThe chemical constituents were isolated by column chromatography on silical gel and sephadex LH -20. Their structures were elucidated on the basis of spectral analysis and physical constants.

RESULTSeven compounds were isolated from this plant and the structures of them were identified as 3, 4, 5-trihydroxybenzoic acid (1), ellagic acid (2), maleic acid (3), quercetin (4), quercetin-3-O-beta-D-galactoside (5), 2alpha, 3alpha, 19alpha, 23-tetrahydroxyurs-12-en-28-oic-acid-28-O-beta-D-glucopyranosyl ester (6), ethyl brevifolin carbosylate (7), respectively.

CONCLUSIONCompounds 1-7 were isolated from this plant for the first time.

Chromatography ; Cornaceae ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Magnetic Resonance Spectroscopy ; Spectrometry, Mass, Electrospray Ionization

To study the chemical constituents of Cymbopogon citratus, isolation and purification of constituents were carried out on silica gel, Sephadex LH-20 and prepatative HPLC. The structures of the compounds were identified by physicchemical properties and spectral data analysis. Eight compounds were isolated and identified as 3beta-methoxy lanosta-9(11)-en-27-ol (1), 3beta-hydroxylanosta-9 (11)-en (2), (24S) -3beta-methoxylanosta-9(11), 25-dien-24-ol (3), 8-hydroxyl-neo-menthol (4), (2E)-3,7-dimethyl-2,7-octadiene-1, 6-diol (5), (+)-citronellol (6), 7-hydroxymenthol (7) and ethyl nonadecanoate(8). Compounds 1 is a new one. Compounds 2-3 are obtained from C. citratus for the first time.
Cymbopogon ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Molecular Structure ; Spectrometry, Mass, Electrospray Ionization ; Triterpenes ; chemistry

OBJECTIVETo study the chemical constituents of Artemisia rupestris.

METHODThe chemical constituents were isolated by column chromatography on silical gel and sephadex LH - 20. Their structures were elucidated on the basis of spectral analysis.

RESULT8 compounds have isolated from this plant, and the structures of them have identified as rupestonic acid (1), chrysosplenetin B (2), artemetin (3), herniarin (4), isokaempferide (5), vanillic acid (6), kaempferol 3, 3', 4'-trimethyl ether (7) and ermanine (8).

CONCLUSIONCompounds 2-8 have been isolated from this plant for the first time.

Artemisia ; chemistry ; Flavonoids ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry ; Umbelliferones ; chemistry ; isolation & purification

OBJECTIVETo study the hypoglycemic effect of the extract of B. polyandra (SHG).

METHODThe diabetic mice were induced by alloxan in ICR mice. The blood glucose concentration was measured by glucose oxidase method. The serum insulin level was determined by 125I-insulin radioimmunoassay kit. The hypoglycemic effect was evaluated by the levels of both fasting and no-fasting blood glucose. The effect on serum insulin level was estimated by the values of the blood insulin and the changes of the blood glucose induced by the glucose intraperitoneal injection. The effect on the glucose absorption was investigated by the oral sucrose or starch tolerance test.

RESULTBoth of the fasting and no-fasting blood glucose levels were decreased significantly by the treatment of 20 or 30 g raw materials crude drug x kg (-1) SHG orally for 7-10 d in ICR mice or in alloxan diabetic mice. In the oral sucrose tolerance test or oral starch tolerance test, the administration of SHG reduced significantly the peak value of the blood glucose and the area under the blood glucose-time curve (AUC) in normal or alloxan diabetic mice, respectively. These effects of SHG were similar to those of acarbose, a kind of alpha-glucosidase inhibitors. In the oral glucose tolerance test in normal and alloxan diabetic mice, SHG decreased both the blood glucose peak and the AUC induced by the glucose loading. But in the intraperitoneal injection glucose tolerance test the levels of insulin in both SHG and control mice were similar, however, the changes of the blood glucose level after the glucose-loading for 30 min in SHG mice was much lower than that in control mice.

CONCLUSIONWith the treatment of SHG, the fasting and no-fasting blood glucose concentrations were decreased and the glucose tolerance improved significantly in both normal and alloxan diabetic mice, and the inhibition of a-glucosidase might be one of its major mechanisms.

Administration, Oral ; Alloxan ; Animals ; Area Under Curve ; Blood Glucose ; analysis ; Diabetes Mellitus, Experimental ; blood ; chemically induced ; Drugs, Chinese Herbal ; administration & dosage ; isolation & purification ; pharmacology ; Glucose ; administration & dosage ; pharmacokinetics ; Glucose Tolerance Test ; Hypoglycemic Agents ; administration & dosage ; isolation & purification ; pharmacology ; Injections, Intraperitoneal ; Insulin ; blood ; Male ; Mice ; Mice, Inbred ICR ; Phytotherapy ; Plants, Medicinal ; chemistry ; Random Allocation ; alpha-Glucosidases ; metabolism

OBJECTIVETo study the chemical constituents of Artemisia rupestris.

METHODThe chemical constituents were isolated by column chromatography on silica gel, polyamide and Sephadex LH-20. Their structures were elucidated on the basis of spectral analysis.

RESULT11 compounds have isolated from this plant, and the structure of them have identified as robinin (1), quercetin (2), linearin (3), luteolin (4), sucrose (5), tilianin (6), luteolin-7-glucoside (7), beta-D-3'-methoxy-4'-O-P-coumaroylglucoside (8), hirsutine (9), 3-(4-methoxy phenyl)-(E)-2-propenoic acid ethyl ester (10), rutin (11).

CONCLUSIONAll this compounds have been isolated from this plant for the first time.

Artemisia ; chemistry ; Chromatography, Gel ; Flavonoids ; chemistry ; isolation & purification ; Luteolin ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry ; Quercetin ; chemistry ; isolation & purification

Background/Aims: Despite the high efficacy of direct-acting antivirals (DAAs), approximately 1–3% of hepatitis C virus (HCV) patients fail to achieve a sustained virological response. We conducted a nationwide study to investigate risk factors associated with DAA treatment failure. Machine-learning algorithms have been applied to discriminate subjects who may fail to respond to DAA therapy. Methods: We analyzed the Taiwan HCV Registry Program database to explore predictors of DAA failure in HCV patients. Fifty-five host and virological features were assessed using multivariate logistic regression, decision tree, random forest, eXtreme Gradient Boosting (XGBoost), and artificial neural network. The primary outcome was undetectable HCV RNA at 12 weeks after the end of treatment. Results: The training (n=23,955) and validation (n=10,346) datasets had similar baseline demographics, with an overall DAA failure rate of 1.6% (n=538). Multivariate logistic regression analysis revealed that liver cirrhosis, hepatocellular carcinoma, poor DAA adherence, and higher hemoglobin A1c were significantly associated with virological failure. XGBoost outperformed the other algorithms and logistic regression models, with an area under the receiver operating characteristic curve of 1.000 in the training dataset and 0.803 in the validation dataset. The top five predictors of treatment failure were HCV RNA, body mass index, α-fetoprotein, platelets, and FIB-4 index. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the XGBoost model (cutoff value=0.5) were 99.5%, 69.7%, 99.9%, 97.4%, and 99.5%, respectively, for the entire dataset. Conclusions Machine learning algorithms effectively provide risk stratification for DAA failure and additional information on the factors associated with DAA failure.

Phytochemical study of the aerial parts of Hypericum perforatum L. resulted in the isolation of an undescribed compound, which was identified as Rel-(2S,3R)-2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-2-methoxy-3-(2-oxopropyl)chroman-4-one (1) by spectroscopic methods including UV, IR, HR-ESI-MS, 1D and 2D NMR spectra. Compound 1 is a new 2,3-dioxo-flavone with an acetonyl moiety, rarely found in nature. In addition, a plausible biogenetic pathway of 1 was proposed in this article.

OBJECTIVE: Larotaxel is a new chemical structure drug, which has not been marketed worldwide. Accordingly, the standard identification and quantification methods for larotaxel remain unclear. The spectrometric analyses were performed for verifying weight molecular formula, molecular weight and chemical structure of larotaxel. Besides, a quantification method was developed for measuring larotaxel in the liposomes. METHODS: The molecular formula, molecular weight and chemical structure of larotaxel were studied by using mass spectrometry (MS), infra-red (IR), nuclear magnetic resonance (NMR) and ultraviolet-visible (UV-vis) spectrometric techniques. The absorption wavelength of larotaxel was investigated by UV-vis spectrophotometry full-wavelength scanning. Besides, a quantification method was developed by high performance liquid chromatography (HPLC), and then validated by measuring the encapsulation efficacy of larotaxel liposomes. RESULTS: The four spectral characteristics of larotaxel were revealed and the corresponding standard spectra were defined. It was confirmed that larotaxel had the structure of tricyclic diterpenoids, with the molecular formula of C45H53NO14, the molecular weight of 831.900 1, and the maximum absorption wavelength of 230 nm. The quantitative method of larotaxel was established by using HPLC with a reversed phase C18 column (5 μm, 250 mm×4.6 mm), a mobile phase of acetonitrile-water (75:25, volume/volume), and a detection wavelength of 230 nm. The validation study exhibited that the established HPLC method was stable, and had a high recovery and precision in the quantitative measurement of larotaxel in liposomes. In addition, a new kind of larotaxel liposomes was also successfully prepared. The particle size of the liposomes was about 105 nm, with an even size distribution. And the encapsulation efficiency of larotaxel in the liposomes was above 80%. CONCLUSION The present study offers reference standard spectra of larotaxel, including MS, IR, NMR, and UV-vis, and confirms the molecular formula, molecular weight and chemical structure of larotaxel. Besides, the study develops a rapid HPLC method for quality control of larotaxel liposomes.
Chromatography, High Pressure Liquid ; Liposomes ; Magnetic Resonance Spectroscopy ; Taxoids