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An HPLC-PAD-MS method has been developed for the qualitative and quantitative analysis of the major chemical constituents in Polygonum multiflorum Thunb. Chromatographic separation was conducted on an Alltima C18 column using water:acetonitrile:acetic acid as the mobile phase. Altogether nine compounds of various classes, including stilbene glucosides, anthraquinone glucosides and anthraquinone derivates, were identified by online ESI/MS. Their identities were ascertained by comparison with data derived from the literature and/or standard compounds. Five components were quantified by HPLC-PAD and the method was fully validated. All the linear regressions were acquired with R2 > 0.99 and the quantification limits (with a signal-to-noise ratio of 3) ranged from 0.63 and 1.57 ng. Repeatability was evaluated by intra- and inter-day assays and RSD value was within 2.47%. Recovery studies for the quantified compounds were found to be within the range 96.32-102.53% with RSD less than 2.35%. The overall procedure is rapid and reproducible and is considered suitable for qualitative and quantitative analysis of a large number of samples.

To measure the acute toxicity of halogenated benzenes to bacteria in natural waters and to study quantitative relationships between the structure and activity of chemicals.The concentration values causing 50% inhibition of bacteria growth (24h-IC50) were determined according to the bacterial growth inhibition test method. The energy of the lowest unoccupied molecular orbital and the net charge of carbon atom of 20 halogenated benzenes were calculated by the quantum chemical MOPAC program.The log1/IC50 values ranged from 4.79 for 2,4-dinitrochlorobenzene to 3.65 for chlorobenzene. A quantitative structure-activity relationship model was derived from the toxicity and structural parameters: log1/IC50 = -0.531(E(LUMO)) + 1.693(Qc) + 0.163(logP) + 3.375. This equation was found to fit well (r2 = 0.860, s = 0.106), and the average percentage error was only 1.98%.Halogenated benzenes and alkyl halogenated benzenes are non-polar narcotics, and have hydrophobicity-dependent toxicity. The halogenated phenols and anilines exhibit a higher toxic potency than their hydrophobicity, whereas 2,4-dinitrochlorobenzene is electrophile with the halogen acting as the leaving group.

A high-performance liquid chromatography-diode array detector-mass spectrometry (HPLC-DAD-MS) analytical method was developed for detection of the nucleosides and nucleobases in two species of Lingzhi, the dried sporophore of Ganoderma lucidum and G. sinense. The method, combining advantages of both DAD and MS, was successfully used to qualitatively identify for six nucleosides namely, adenosine, cytidine, guanosine, inosine, thymidine, uridine and five nucleobases namely, adenine, guanine, hypoxanthine, thymine and uracil in Lingzhi samples. Quantitative analyses showed that uridine was the most abundant nucleoside in these Lingzhi samples and the contents of nine target analytes were found to be different in pileus and stipes of the fruiting bodies and among the different species of G. spp. The established method might apply as an alternative approach for the quality assessment of Lingzhi.

An HPLC-DAD fingerprinting profile of Rhizoma Et Radix Polygoni Cuspidati was established basing on the consistent chromatographic features of 24 authentic herb samples. The major types of chemical constituents, stilbenes and anthraquinones, were analyzed and included in the fingerprint. Eight common peaks of Polygonum Cuspidatum were identified by using HPLC-MS. The developed fingerprint was applied to differentiate Rhizoma Et Radix Polygoni Cuspidati from Radix Polygoni Multiflori and Radix Et Rhizoma Rhei. Although the three herbs belong to the family of Polygonaceae, the results indicated that these could be differentiated by using the established method.

Using the HPLC/DAD/ESI/MS method, the qualitative and quantitative analysis of senkyunolide A (SA) in the rhizomes of Ligusticum chuanxiong (Rhizoma chuanxiong; CX) and roots of Angelica sinensis (DG) was established. As a result, it was found that SA is a characteristic standard compound for the quality evaluation and chemical differentiation between CX and DG. Methanol was chosen in the preparation of standard solutions and extraction of samples based on the stability data. The identity of SA in CX and DG was unambiguously determined based on the quasimolecular ions in ESI-MS. A comprehensive validation of the method, including sensitivity, linearity, reproducibility and recovery, was conducted using the optimized chromatographic conditions. The linear calibration curve was acquired with R2>0.999 and limit of detection (S/N=3) was estimated to be 12.5 mug/g. The reproducibility was evaluated by repeated sample injection and replicated analysis of samples with the relative standard deviation (RSD) value found within 0.68%. The recovery rates of SA varied within the range of 96.91-101.50% with RSD less than 2.38%. In the present work, the contents of SA were quantified within 3.94-9.14 mg/g and 0.108-0.588 mg/g for 12 batches each of CX and DG. The results demonstrated that SA is a useful standard compound for the quality evaluation and chemical differentiation between CX and DG. The analytical procedure is precise and reproducible and thus suitable for the analysis of a large number of samples.

To measure the 96h-LC50 values of 32 substituted benzenes to the carp and to study the relationship between quantitative structure-activity and structural parameters of chemicals.The acute toxicity values of 32 substituted benzenes to the carp were determined in a semistatic test. The energy of the lowest unoccupied molecular orbital, and the highest occupied molecular orbital, the dipole moment and the molecular weight of substituted benzenes were calculated by the quantum chemical method MOPAC6.0.The range of the toxicity of studied compounds was broad, and the most toxic compound was pentachlorophenol, while the least toxic compound was 4-methylaniline. By the stepwise regression analyses, a series of Quantitative structure-activity relationships (QSAR) equations were derived from all compounds and subclasses. The equation log1/LC5o=0.759logP + 2.222 (R2 (adj)=0.818) was found to fit well and the average predicted percentage error was 6.16%.The toxicity of anilines and phenols to the carp could be modeled well by logP alone, whereas the toxicity of the halogenated benzenes and nitrobenznes not containing hydroxyl or amino group can be controlled by hydrophobic and electronic factors.

To study pharmacological effects of PEC (the oral liquid which consists of Panax quinquefolium, Epimedium brevicornum, Schisandra chinensis Bail and Cervus eplaphus) on mice.Experiments were carried out through swimming test, step-through, spontaneous activity and sleeping time.When 5-10 mL x kg(-1) of PEC was given orally for 7 days, it could prolong swimming duration of mice in water tank, and increase the tolerant ability against oxygen-deficiency. PEC could also improve cognitive-deficiency induced by taking off sleep with force in mice after given orally for 7 days. The PEC could increase the spontaneous activity in mice, antagonize the inhabitation induced by Valium, and shorten the sleeping time caused by sodium pentobarbital.PEC has strong potential neuro-pharmacological activities such as anti-fatigue, improving cognitive-deficiency in mice.

A reversed phase high-performance liquid chromatographic method was developed for quantifying E-ligustilide (1) and Z-ligustilide (3) in the roots of Angelica sinensis (Oliv.) Diels with confirmation using UV, atmospheric pressure chemical ionisation (APCI) MS and APCI-MS-MS techniques. Based on the UV spectra of compounds 1, E-butylidenephthalide (2), 3 and Z-butylidenephthalide (4), the absorption at 350 nm was chosen as measuring wavelength in which baseline separation of compounds 1 and 3 could be obtained but avoided the interference of compounds 2 and 4. The identity of compounds 1 and 3 in samples were unambiguously determined by the respective quasi-molecular ions ([M+H]+) in APCI-MS. According to the stability data, acetonitrile was chosen for the preparation of standard solutions in order to minimize the isomerization of compound 3. Compounds 1 and 3 were qualitatively and quantitatively analyzed in seven samples of the roots of Angelica sinensis (Oliv.) Diels, Angelica acutiloba Kitagawa, Angelica acutiloba Kitagawa var. sugiyamae Hikino and the rhizome of Ligusticum chuanxiong Hort. Analysis of an extract from a sample root of Angelica gigas Nakai using LC-MS for the first time could not detect the presence of ligustilide in this herb. The overall analytical procedure is rapid and reproducible which is considered suitable for quantitative analysis of large number of samples.

To investigate the differential diagnosis between Graves's disease and Hashimoto's hyperthyroidism to improve positive diagnostic rate in Hashimoto's hyperthyroidism, to facilitate proper management.Cytological examination was conducted by fine needle biopsy (FNB) on the thyroids of patients with hyperthyroidism diagnosed by clinical data, including 22 cases of Hashimoto's hyperthyroidism, 5 males and 17 females, aged 39 +/- 12, and 49 cases of Graves's disease, 20 males and 29 females, aged 41 +/- 11. Thyroid auto-antibodies-thyroid peroxidase antibody (TPOAb), thyroid microsomal antibody (TMA), thyroglobulin antibody (TGA), thyroid-stimulating hormone receptor antibody (TRAb), and free serum triiodothyronine (FT3), free thyroxin (FT4), and serum thyroid-stimulating hormone (S-TSH) were tested. The correlation between the pathology of thyroid and different autoantibodies and thyroid hormone was analyzed.TRAb was 42.28 +/- 75.89 in Graves disease group, significantly higher than that in Hashimoto's hyperthyroidism group (5.77 +/- 12.69, P0.001). FT3 was 16.13 +/- 9.95, significantly higher than that in Hashimoto's hyperthyroidism group (9.54 +/- 6.76, P0.01). In Graves's disease group the positive rates for TRAb, TPOAb, TMA, and TGA were 83.67%, 75.51%, 57.14% and 48.98% respectively. In Hashimoto's hyperthyroidism group, the positive rate for TRAb was 13.64%, and the positive rates for the rest autoantibodies were all 86.36%. The double positive rate of TPOAb and TGA was 86.36% in Hashimoto's hyperthyroidism group, significantly higher than that in Graves's disease group (48.98%). There was a positive association between TRAb and FT3, and between diffuse and symmetric increased size of thyroid and FT3 TRAb.Comprehensive analysis of TRAb, TPOAb, TGA, and FT3 is helpful to the differential diagnosis between Graves's disease and Hashimoto's hyperthyroidism.

The biodegradability of 30 substituted phenols and benzoic acids was determined by BOD technique. The molecular weight (Mw), heat of formation (Hf) and the energy of the highest occupied molecular orbital (E(Homo)) of the studied compounds were calculated by the quantum chemical method MOPAC6.0-AMI. The quantitative structure-biodegradability relationships (QSBRs) were developed by the linear regression method and neural network approach, respectively. It has been shown that the neural network method is able to provide a superior fit to the training set data and test set data and produce a lower prediction error than the linear regression method.

50% effective inhibition concentration 48h-EC50 of 40 substituted benzenes to the algae (Scenedesmus obliquus) was determined. The energy of the lowest unoccupied molecular orbital (ELUMO) was calculated by the quantum chemical method MOPAC6.0-AM1. By using ELUMO and the hydrophobicity parameter log KOW the quantitative structure–activity relationship model (QSAR) was developed: log 1/ EC 50 =0.272 log KOW − 0.659ELUMO + 2.54, R2=0.793, S.E.=0.316, F=71.07, n=40. A series of equations were obtained about the measured EC50 values of different subclasses of compounds. For those compounds containing double –NO2, their toxicity may be related chiefly to the intracellular reduction of –NO2 obtaining electron, while for anilines and phenols, KOW contributes most to the QSAR and ELUMO very little.

Since nitrobenzenes constitute a class of industrial chemicals that are present in Songhua River and probably in many other industrialized countries as well, it is useful to gain insight into their potential hazard to aquatic organisms. For this reason, it was decided to determine data on the toxicity for bacteria in the Songhua River. Furthermore, the toxicity to Ph. phosphoreum was determined in the Microtox assay, in order to further evaluate the usefulness of this assay for hazard assessment. Quantitative structure-activity relationships (QSARs) have been developed for aromatic nitro compound toxicity to aquatic species, but no data on the toxicity of nitrobenzenes to environmental bacteria were used. In this study, the toxicity of various substituted nitrobenzenes to bacteria in Songhua River and to Ph. phosphoreum has been investigated, establishing quantitative structure-activity relationships with n-octanol-water partition coefficient (log P), the energy of the lowest unoccupied molecular orbital (E{sub LUMO}) and the sum of substituent constant ({Sigma}{sigma}-). 12 refs., 2 tabs.

The freshwater fish Carassius auratus was chosen as an experimental subject, and their hepatic biochemical responses to the medium-term exposure of Benzo(k)fluoranthene (BkF) alone and in combination with PCB118 and dichlorodiphenyltrichloroethane (DDT) were investigated by measuring the reduced glutathione (GSH), glutathione S-transferase (GST), and thiobarbituric acid reactive substances (TBARS), to assess sublethal effects. The hepatic GSH content was significantly inhibited by organic pollutants, alone and in mixtures, while the TBARS content was significantly induced after three days of exposure. Bell-shaped concentration-response charts of GST activities were obtained. Significant dose-response relationships were found for hepatic GSH and TBARS contents of all concentrations and for the GST activity, except at the highest concentration. The GSH content, GST activity, and TBARS content in Carassius auratus were confirmed as useful biomarkers of exposure to organic pollutions.