[Research progress of steroidal saponins in Paris polyphylla var. yunnanensis and their microbial transformation].

Steroidal saponins, important natural organic compounds in Paris polyphylla var. yunnanensis, have good biological activity. Structural modification of steroidal saponins by microbial transformation could produce a large number of products with novel structures and excellent bioactivity, which can provide functional compounds for the research and development of steroidal drugs. This study summarized the research progress in steroidal saponins and their microbial transformation in P. polyphylla var. yunnanensis. P. polyphylla var. yunnanensis contains 112 steroidal saponins, 8 of which are used as substrates in 35 transformation reactions by 25 microbial species, with the highest transformation rate of 95%. Diosgenin is the most frequently used substrate. Furthermore, the strains, culture medium, reaction conditions, transformation rate, transformation reaction characteristics, and biological activities of the transformed products were summarized. This review may provide reference for the further research on microbial transformation of steroidal saponins in P. polyphylla var. yunnanensis.

Steroid glycosides isolated from Paris polyphylla var. chinensis aerial parts and paris saponin II induces G1/S-phase MCF-7 cell cycle arrest.

In our previous research on Vietnamese medicinal plants, we found that the ethanolic extract of the aerial parts of Paris polyphylla var. chinensis exhibited cytotoxic effects in vitro in the MCF-7 human cancer cell line. Here, we used combined chromatographic separations to isolate six compounds including a new steroid glycoside, paripoloside A (3), and five known compounds, from the butanol extract of the aerial parts of P. polyphylla. We unambiguously elucidated their structures based on spectroscopic data (proton and carbon-13 nuclear magnetic resonance, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, correlation spectroscopy, and high-resolution electrospray ionization mass spectroscopy data), and chemical reactions. Among the isolated compounds, paris saponin II (PSII) had the strongest cytotoxic effects against MCF-7 breast cancer cells. Interestingly, PSII significantly increased the expression of p53, p21, p27, and Bax protein levels and significantly suppressed the expression of cyclin D1 and retinoblastoma protein. These data suggest that PSII may induce G1/S phase cell cycle arrest and apoptosis pathway development in MCF-7 cells. Furthermore, the MCF-7 breast cancer cells mechanism of PSII was also investigated using molecular docking. Together, our results demonstrate that isolated compounds from P. polyphylla are promising candidates as breast cancer inhibitors.

The power of hyphenated chromatography-Time of flight mass spectrometry for unequivocal identification of spirostanes in bodybuilding dietary supplements.

A previously unidentified purported botanical ingredient was found in dietary supplements marketed for anabolic benefits. In an attempt to assess the 'naturalness' of a group of steroid-like compounds called laxogenins, a UHPLC-QToF method was developed. Several dietary supplements claim to contain 5α-hydroxy laxogenin, which is a derivative of a naturally occurring spirostane-type steroid, laxogenin. Although laxogenin has been isolated from the rhizomes of Smilax sieboldii, 5α-hydroxy laxogenin has not been isolated or reported from any natural source. These derivatives of laxogenins have untested anabolic properties. Due to the low UV absorbance of the spirostanes, a mass spectrometric method in positive ion mode was developed for unambiguous identification of laxogenin and closely related compounds. To show the utility of the developed method, twelve dietary supplements labeled to contain 5α-hydroxy laxogenin or laxogenin as 5α-hydroxy laxogenin were analyzed as a proof-of-concept. Five supplements did not contain any 5α-hydroxy laxogenin, whereas in the remaining seven samples, spirostane-type contaminants were identified along with the labeled 5α-hydroxy laxogenin. The identity of some of these contaminants was established based on reference standards along with mass fragmentation patterns. One of the unlabeled contaminants was identified as the phytosteroid saponin, diosgenin, a common starting precursor of several steroidal drugs. Several synthetic derivatives of diosgenin were identified in the eight products. These findings indicate that the labeled 5α-hydroxy laxogenin along with other spirostanes found in supplements are synthetic and signify a lack of quality controls. Additionally, an unlabeled, anabolic androgenic steroid, arimistane, an aromatase inhibitor, was also identified in one product. Laxogenin, was not detected in any of the samples analyzed during this investigation.

Purification of the total steroidal saponins from fenugreek seeds ( Trigonella foenum- graecum L.) using aqueous two-phase system and determination of diosgenin content using micellar electrokinetic chromatography method.

The total steroidal saponins, particularly its major steroidal sapogenin (diosgenin), are the main active principles of fenugreek seed extract. In this study, an ethanol-salt aqueous two-phase system (ATPS) was explored for the purification of the total steroidal saponins, and the process conditions were optimized by response surface methodology (RSM). Under the optimized conditions, the RSM predicted recovery of the total steroidal saponins in the top phase of ATPS was 97.9%, which agreed with the average experimental recovery (98.3 ± 4.2% ( n = 6)). Moreover, a rapid micellar electrokinetic chromatography (MEKC) method was developed for the determination of diosgenin from extracts. The diosgenin content in the ATPS top phase extract was 3-fold higher than that in crude extract, suggesting this ATPS having a great potential for purification pharmacological active ingredients from fenugreek seeds.

Tribulus terrestris Protects against Male Reproductive Damage Induced by Cyclophosphamide in Mice.

Tribulus terrestris (TT) has been considered as a potential stimulator of testosterone production, which has been related with steroidal saponins prevailing in this plant. Cyclophosphamide (CP) is the most commonly used anticancer and immunosuppressant drug, which causes several toxic effects, especially on the reproductive system. Patients who need to use CP therapy exhibit reduced fertility or infertility, which impacts both physically and emotionally on the decision to use this drug, especially among young men. We hypothesized that the treatment with TT dry extract would protect the male reproductive system against CP toxicity. Mice received dry extract of TT (11 mg/kg) or vehicle by gavage for 14 days. Saline or CP was injected intraperitoneally at a single dose (100 mg/kg) on the 14th day. Animals were euthanized 24 h after CP administration, and testes and epididymis were removed for biochemical and histopathological analysis and sperm evaluation. The dry extract of TT was evaluated by HPLC analysis and demonstrated the presence of protodioscin (1.48%, w/w). CP exposure increased lipid peroxidation, reactive species, and protein carbonylation and altered antioxidant enzymes (SOD, CAT, GPx, GST, and GR). Moreover, acute exposure to CP caused a reduction on 17 ß-HSD activity, which may be related to the reduction in serum testosterone levels, histopathological changes observed in the testes, and the quality of the semen. The present study highlighted the role of TT dry extract to ameliorate the alterations induced by CP administration in mice testes, probably due to the presence of protodioscin.

LC-MS determination of steroidal glycosides from Dioscorea deltoidea Wall cell suspension culture: Optimization of pre-LC-MS procedure parameters by Latin Square design.

In this paper, the ultrasound assisted extraction method for isolation of steroidal glycosides from D. deltoidea plant cell suspension culture with a subsequent HPLC-MS determination was developed. After the organic solvent was selected via a two-factor experiment the optimization via Latin Square 4 × 4 experimental design was carried out for the following parameters: extraction time, organic solvent concentration in extraction solution and the ratio of solvent to sample. It was also shown that the ultrasound assisted extraction method is not suitable for isolation of steroidal glycosides from the D. deltoidea plant material. The results were double-checked using the multiple successive extraction method and refluxing extraction. Optimal conditions for the extraction of steroidal glycosides by the ultrasound assisted extraction method were: extraction time, 60 min; acetonitrile (water) concentration in extraction solution, 50%; the ratio of solvent to sample, 400 mL/g. Also, the developed method was tested on D. deltoidea cell suspension cultures of different terms and conditions of cultivation. The completeness of the extraction was confirmed using the multiple successive extraction method.

Comparative metabolic profiling of Costus speciosus leaves and rhizomes using NMR, GC-MS and UPLC/ESI-MS/MS.

Costus speciosus had been used in oriental systems of medicines, to treat diverse ailments. The present study was focused on NMR, GC-MS and UPLC/ESI-MS/MS-based metabolic profiling of C. speciosus. This metabolic study resulted in the identification of 91 and quantification of 69 metabolites. Caffeic acid derivatives previously unreported in C. speciosus were also identified. High quantity of steroidal saponins namely methyl protogracillin (297.97 ± 0.07 mg/g dried wt.) and dioscin (158.72 ± 0.27 mg/g dried wt.) were observed in butanol fraction of rhizomes. Health care metabolites including caffeic acid (37.88 ± 0.04 mg/g dried wt.) and trehalose (75.12 ± 0.08 mg/g dried wt.) were also detected in ethyl acetate and aqueous fractions of rhizomes, respectively. Metabolites of nutraceutical and biological significance including eremanthine (5.14 ± 0.68%, peak area), tocopherols (~22%), sterols (~25%) were also identified from hexane fractions of rhizomes and leaves using GC-MS. The analytical techniques used had successfully differentiated metabolites composition among leaves and rhizomes.

[Rapid prediction of the content of polyphyllin in various species of Paris by infrared spectrometry].

Polyphyllin is the main active constituent in Paris which was a traditional Chinese medicine. In order to evaluate the quality of Paris rapidly and ensure the efficacy in clinical therapy, we quantified the contents of polyphyllin Ⅰ, polyphyllin Ⅱ and polyphyllin Ⅶ using infrared spectroscopy with partial least squares regression(PLSR). The method for evaluating the quality of Paris was established. Infrared spectra of 78 samples from various species in different origins were collected. The contents of polyphyllin Ⅰ, Ⅱ and Ⅶ were determined by high performance liquid chromatography(HPLC). The HPLC data were combined with the spectral data to predict the contents of three polyphyllin rapidly. Multiplicative signal correction(MSC), standard normal variate(SNV), orthogonal signal correction(OSC), first derivative and second derivative were utilized for the spectral preprocessing. Then, the optimized spectral data were used to establish the quantitative prediction model based on PLSR. The results showed that the best spectral pretreatment of polyphyllin Ⅰ and Ⅱ were MSC+OSC+2nd Der and that of polyphyllin Ⅶ was MSC+SNV+OSC+2nd Der. In the quantitative calibration model, the determination coefficients (R²) of polyphyllin Ⅰ, polyphyllin Ⅱ and polyphyllin Ⅶ were 0.930 8, 0.934 8 and 0.912 3, respectively while the Root mean square error of estimation(RMSEE) were 1.855 0, 0.632 3 and 0.001 6 mg•g⁻¹, respectively. In the verification model, the R² of polyphyllin Ⅰ, polyphyllin Ⅱ and polyphyllin Ⅶ were 0.948 8, 0.703 6 and 0.801 7, respectively, and the root mean square error of prediction(RMSEP)were 1.704 6, 1.227 8 and 0.002 0 mg•g⁻¹, respectively. Because of the predictive value of quantitative model was closed to the real value, the effect of the model was good. The model of polyphyllin Ⅰ and Ⅱ were better than that of polyphyllin Ⅶ. The developed method was non-destructive, fast, and accurate. It was feasible to determine the content of polyphyllin in Paris.

Isolation and chemoenzymatic treatment of glycoalkaloids from green, sprouting and rotting Solanum tuberosum potatoes for solanidine recovery.

The estimation of glycoalkaloids in the flesh of different types of decayed potatoes was evaluated. The results showed that turned green and also sprouting or rotting potato flesh contain high amounts of toxic solanine and chaconine, exceeding by 2-5-fold the recommended limit, and ranging from 2578±86mg/kg to 5063±230mg/kg of dry weight potato flesh. For safety consideration, these decayed potatoes should be systematically set aside. To avoid a net economic loss and encourage the removal of this hazardous food, a recycling process was investigated to generate added-value compounds from the toxic glycoalkaloids. A simple chemo-enzymatic protocol comprising a partial acidic hydrolysis followed by an enzymatic treatment with the ß-glycosidase from Periplaneta americana allowed the efficient conversion of α-chaconine to solanidine.

Combined Application of UHPLC-QTOF/MS, HPLC-ELSD and 1 H-NMR Spectroscopy for Quality Assessment of DA-9801, A Standardised Dioscorea Extract.

INTRODUCTION: DA-9801, a standardised 50% aqueous ethanolic extract of a mixture of Dioscorea japonica and D. nipponica, is a botanical drug candidate for the treatment of diabetic neuropathy, which finished its US phase II clinical trials recently. An advanced quality control method is needed for further development of DA-9801, considering its high contents of both primary and secondary metabolites. OBJECTIVE: Development of a quality assessment strategy for DA-9801, based on the combination of UHPLC-QTOF/MS, HPLC-ELSD, and 1 H-NMR spectroscopy. METHODS: The method was developed and tested with 15 batch products of DA-9801. The steroidal saponins of DA-9801 were tentatively identified by UHPLC-QTOF/MS and were quantified with the validated HPLC-ELSD method. Primary metabolites of DA-9801 were identified and profiled using 1 H-NMR spectrometry. The batch-to-batch equivalence of DA-9801 was tested with the 1 H-NMR spectra using spectral binning, correlation analysis, and principal component analysis. RESULTS: Six major saponins of DA-9801 were tentatively identified by UHPLC-QTOF/MS. Among them, protodioscin and dioscin were quantified by the validated HPLC-ELSD method. Twenty-six metabolites were identified in 1 H-NMR spectra. The similarity between DA-9801 batches could be evaluated with the NMR spectra of DA-9801. The 1 H-NMR method also revealed that two Dioscorea species contributed distinct amino acids to the contents of DA-9801. CONCLUSION: This study validates the effectiveness of UHPLC-QTOF/MS, HPLC-ELSD, and 1 H NMR-combined method for quality control of DA-9801 and its crude materials. Copyright © 2016 John Wiley & Sons, Ltd.

Mitochondrial dysfunction in H9c2 cells during ischemia and amelioration with Tribulus terrestris L.

AIMS: The present study investigates the protective effect of partially characterized Tribulus terrestris L. fruit methanol extract against mitochondrial dysfunction in cell based (H9c2) myocardial ischemia model. MAIN METHODS: To induce ischemia, the cells were maintained in an ischemic buffer (composition in mM -137 NaCl, 12 KCl, 0.5 MgCl2, 0.9 CaCl2, 20 HEPES, 20 2-deoxy-d-glucose, pH-6.2) at 37°C with 0.1% O2, 5% CO2, and 95% N2 in a hypoxia incubator for 1h. Cells were pretreated with various concentrations of T. terrestris L. fruit methanol extract (10 and 25µg/ml) and Cyclosporin A (1µM) for 24h prior to the induction of ischemia. KEY FINDINGS: Different parameters like lactate dehydrogenase release, total antioxidant capacity, glutathione content and antioxidant enzymes were investigated. Studies were conducted on mitochondria by analyzing alterations in mitochondrial membrane potential, integrity, and dynamics (fission and fusion proteins - Mfn1, Mfn2, OPA1, Drp1 and Fis1). Various biochemical processes in mitochondria like activity of electron transport chain (ETC) complexes, oxygen consumption and ATP production was measured. Ischemia for 1h caused a significant (p≤0.05) increase in LDH leakage, decrease in antioxidant activity and caused mitochondrial dysfunction. T. terrestris L. fruit methanol extract pretreatment was found effective in safeguarding mitochondria via its antioxidant potential, mediated through various bioactives. HPLC of T. terrestris L. fruit methanol extract revealed the presence of ferulic acid, phloridzin and diosgenin. SIGNIFICANCE: T. terrestris L. fruit ameliorate ischemic insult in H9c2 cells by safeguarding mitochondrial function. This validates the use of T. terrestris L. against heart disorders.

[New variety breeding of Dioscorea alata, cultivar "Wenshanyao No.1].

To breed a new yam cultivar of Dioscorea alata, the different and excellent germplasm resources were investigated within artificially cultivated population and some superior individuals, with a higher yield and medicinal properties, were selected. Considering results of the yield and medicinal properties during 2006-2013 cropping season, strains and lines were established and selected. As a result, the yield of the new developed cultivar (Wenshanyao No. 1, WSY01-1) reached 2217. 0 kg per 667 m2 (fresh weight) and 348.3 kg per 667 m2 (dry weight), and increased 23.8% and 23.9% comparing with control cultivars (landraces). Comparing with control cultivars, the level of polysaccharide, allantoin, and dioscin increased 36.9%, 48.3%, 20.9%, and reached 12.2%, 1.30%, 579.7 µg · g(-1), respectively. This result showed that the systematic selection method can significantly improve yield and medicinal properties of D. alata, and the developed " Wenshanyao No. 1" exhibits wide spreading prospects.

Comparative analysis of diosgenin in Dioscorea species and related medicinal plants by UPLC-DAD-MS.

BACKGROUND: Dioscorea is a genus of flowering plants, and some Dioscorea species are known and used as a source for the steroidal sapogenin diosgenin. To screen potential resource from Dioscorea species and related medicinal plants for diosgenin extraction, a rapid method to compare the contents of diosgenin in various plants is crucial. RESULTS: An ultra-performance liquid chromatography (UPLC) coupled with diode array detection (DAD) and electrospray ionization mass spectrometry (ESI-MS) method was developed for identification and determination of diosgenin in various plants. A comprehensive validation of the developed method was conducted. Twenty-four batches of plant samples from four Dioscorea species, one Smilax species and two Heterosmilax species were analyzed by using the developed method.The present method presented good sensitivity, precision and accuracy. Diosgenin was found in three Dioscorea species and one Heterosmilax species, namely D. zingiberensis, D. septemloba, D. collettii and H. yunnanensis. CONCLUSION: The method is suitable for the screening of diosgenin resources from plants. D. zingiberensis is an important resource for diosgenin harvesting.

Prediction of anti-tumor chemical probes of a traditional Chinese medicine formula by HPLC fingerprinting combined with molecular docking.

A traditional Chinese medicine formula (Fuzheng Yiliu decoction; FZYLD) has been used for many years in clinical settings to cure liver tumors; however, no empirical research has reported its chemical composition. In this paper, 21 chief constituents were distinguished from FZYLD using high-performance liquid chromatography-mass spectrometry fingerprint analysis. Molecular docking studies for B-cell lymphoma-extra large (Bcl-XL), interleukin (IL)-2, and tumor necrosis factor-α (TNF-α) were bound to evaluate their anticancer activities. 7 compounds showed potential Bcl-XL high affinity binding with a dissociate constant (Kd) < 10 µM; 7 compounds bound with IL-2 had a Kd < 10 µM; and 11 compounds showed potential TNF-α inhibition with a Kd < 10 µM. Moreover, 11 compounds showed better anticancer activity toward human HepG2 (hepatoma) cancer cell lines with IC50 values < 100 µM in vitro. The killings effects of natural killer cells can be activated by FZYLD on HepG2 cells and regulate the immune response through modulating IL-2 and TNF-α expression in vivo. In the "Fuzheng" Chinese medicine formula, many substances participate in the complex regulation of the immune network to execute the anti-tumor effect. The combination approach of chromatographic fingerprint and computer virtual docking used to explore active chemical matter of traditional Chinese medicine is extremely valuable.

A comparative tissue-specific metabolite analysis and determination of protodioscin content in Asparagus species used in traditional Chinese medicine and Ayurveda by use of laser microdissection, UHPLC-QTOF/MS and LC-MS/MS.

INTRODUCTION: Asparagus is esteemed in Traditional Chinese Medicine and Ayurveda, and it is commercially one of the most important drugs in the global herbal market. Comparative metabolite profiling of different species would help in determining the similarities and ascertain their validity for being used as substitutes for each other. Laser microdissection (LMD) facilitates identification of metabolites in specific tissues, and thus it can aid in exploration of metabolic pathways in target tissues. OBJECTIVE: To compare tissue-specific metabolites and protodioscin content of Asparagus cochinchinensis (Lour.) Merr. and Asparagus racemosus Willd. used in China and India. METHODS: Metabolite analysis of laser-dissected tissues was carried out using UHPLC-QTOF/MS and LC-MS/MS. The protodioscin contents were determined and the method was validated as per the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines. RESULTS: Metabolite analysis reveals that the velamen tissue, among other tissues such as cortex, vascular bundles and pith, contained maximum components, specifically those belonging to the steroidal saponin class. Although the metabolite profiles were similar, the content of protodioscin was found to be higher in Chinese than Indian species. CONCLUSION: The study provided a suitable methodology for metabolite profiling and protodioscin content determination of Asparagus by use of LMD, UHPLC-QTOF/MS and LC-MS/MS. The similarities in metabolite profiles indicate that Asparagus species from India and China can serve as substitute for each other in various therapeutic and pharmaceutical applications.

Chemical fingerprint analysis and quantitative determination of steroidal compounds from Dioscorea villosa, Dioscorea species and dietary supplements using UHPLC-ELSD.

Ultra high-performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC™ system with an UPLC™ BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5-12 µg/mL with 2 µL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra- and inter-day experiments were <3.1%, and the recovery efficiency was 97-101%. The total content of standard compounds was found to be in the ranges 0.01-14.5% and 0.9-28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC-mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products.

[Study on inducing embryogenic callus of Dioscorea zingiberensis by orthogonal design].

OBJECTIVE: To select the suitable medium to induce embryogenic callus of Dioscorea zingiberensis. METHODS: Plantlet of Dioscorea zingiberesis in vitro was obtained by using apical meristem as explant. The different parts of the plantlets were cultured to select the best explant used for inducing callus and embryoids. Growing rate and diosgenin content were calculated in orthogonal test to optimize combination of phytohormones for inducing embryogenic callus. RESULTS: The leaves were suitable explants to induce callus and embryoid. The inducing rate of callus and embryoids reached 92.5% and 42.5%, respectively. The optimal medium for inducing embryogenic callus was MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + 2,4-D 1.0 mg/L. CONCLUSION: The results of this study can be used for effective induction of embryogenic callus of Dioscorea zingiberensis, and lay the foundation for the subsequent research of artificial seeds.

Ethylene treatment improves diosgenin accumulation in in vitro cultures of Dioscorea zingiberensis via up-regulation of CAS and HMGR gene expression

Background: The perennial medicinal herb Dioscorea zingiberensis is a very important plant used for steroid drug manufacturing for its high level of diosgenin in rhizome. Although the stimulation of diosgenin accumulation by ethylene has been reported in a few of plant species, its regulation is not yet characterized at the molecular level, the underlying molecular mechanism remains elusive. Results: In this study, the effects of ethylene on diosgenin biosynthesis in in vitro cultures of D. zingiberensis were described. The results showed that, in samples treated with ethylene at concentration E3 (10(4) dilution of 40% ethephon), the diosgenin biosynthesis was significantly promoted in comparison with the control samples. Treatment with high concentrations of ethylene had inhibitory effect, whereas with low concentration of the gas elicitor brought about no detectable deleterious effect on the growth rate and diosgenin content of the cultures. The considerable increase of diosgenin level in in vitro cultured Dioscorea zingiberensis by ethylene application is accompanied by the concomitant increase of soluble proteins and chlorophyll content. The gene expressions of cycloartenol synthase and 3-hydroxy-3-methylglutaryl-CoA reductase but not of squalene synthase or farnesyl pyrophosphate synthase were up-regulated by applied ethylene. Conclusions: Our results suggest that ethylene treatment enhanced diosgenin accumulation via up-regulation of the gene expressions of cycloartenol synthase and 3-hydroxy-3-methylglutaryl-CoA reductase.

Bioassay-guided evaluation of Dioscorea villosa - an acute and subchronic toxicity, antinociceptive and anti-inflammatory approach.

BACKGROUND: Dioscorea villosa (DV) has been used in Brazil as an alternative medicine to attenuate menopause symptoms, as well as for the treatment of joint pain and rheumatoid arthritis. In spite of the popular use of DV for the treatment of various disorders, there are limited scientific data regarding safety aspects of this herb. In this regard, we carried out to evaluated both antinociceptive and anti-inflammatory activities in experimental models and assess the toxic effects of the acute (single dose) and subchronic (30 days) oral administration of dry extract of Dioscorea villosa in rodents. METHODS: The LC analyses were performed to assess the presence of the diosgenin in samples of DV. The antinociceptive study of DV was performed using models of acetic acid-induced writhing and formalin-induced pain in mice. The anti-inflammatory study was accomplished by leukocyte migration to the peritoneal cavity. A dry extract of DV was tested at doses of 100, 200 and 400 mg/kg (per os or p.o.). The toxicological properties of the dry extract were evaluated by toxicity assays of acute (5 g/kg, single dose) and subchronic (1 g/kg/day, 30 days) treatment. Haematological, biochemical, and histopathological parameters were studied. The results are expressed as mean ± S.D., and statistical analysis of the data were performed with the Student's t-test or one-way analysis of variance (ANOVA) followed by Tukey's test. In all cases differences were considered significant if p < 0.05. RESULTS: HPLC-DAD analysis of the extract from DV revealed the presence of diosgenin as the major compound. Doses of 200 and 400 mg/kg significantly reduced the amount of acetic acid-induced writhing in relation to the vehicle (p < 0.0001). In the first phase, using the formalin-induced neurogenic pain test, only the 400 mg/kg dose of DV showed significant inhibition of neurogenic pain (p < 0.001). In the second phase, 200 and 400 mg/kg of DV showed significant inhibition of inflammatory pain (p < 0.0001). Significant inhibition of leukocyte migration was observed with doses of 100 (p < 0.001), 200 (p < 0.01) and 400 mg/kg (p < 0.01). Haematological, biochemical and histopathological data obtained in both acute and subchronic toxicological assays revealed only unremarkable changes, which are unlikely to indicate DV toxicity with oral administration. CONCLUSION: We found that DV possesses antinociceptive and anti-inflammatory properties in rodent models. In addition, no acute or subchronic toxicity was evident when the herbal extract was administered orally. These results supporting the folkloric usage of the plant to treat various inflammatory diseases.

Rapid quantitative analysis of diosgenin in the tubers of Dioscorea zingiberensis C.H. Wright by coupling cellulose enzymolysis and two-phase acid hydrolysis in tandem with HPLC-UV.

A rapid method was developed to quantify diosgenin in Rhizoma Dioscoreae Zingiberensis. For the first time, sample solution was prepared by coupling pretreatment of raw material in cellulase and two-phase acid hydrolysis. After reconstitution, analysis was carried out on a C18 column, at 30°C, with acetonitrile and water (70:30, v/v) as mobile phase with flow rate of 1.0 mL min(- 1). Detection was carried out at 202 nm. Good linearity (r(2) = 0.9998) was established between concentration of analyte and peak area. The precision was >99% and the RSD of diosgenin contents for repeatability was 1.81%. The accuracy was supported with recoveries at 98.8%, 101.6% and 101.2%. The sample solution prepared using the proposed method contained higher content of diosgenin and was stable for 48 h. Due to the high efficiency of sample preparation and high reliability of the HPLC method, it is feasible to use this method for routine analysis of diosgenin in the herb.