High-performance liquid chromatographic analysis of bioactive triterpenes in Perilla frutescens

Hsian-tsao (Mesona procumbens Heml.) prevents against rat liver fibrosis induced by CCl(4) via inhibition of hepatic stellate cells activation

In this study, the protective effect of extract of Hsian-tsao (Mesona procumbens) (EHT) against liver fibrogenesis in carbon tetrachloride (CCl(4))-injured rats was evaluated. The inhibitory effect of oleanolic acid (OA) and ursolic acid (UA), which are the active compounds in EHT, on the activation of hepatic stellate cells (HSC) was also determined. The results showed that EHT at a dosage of 1.2g/kg of b.w. significantly reduced the liver injury induced by CCl(4) in rats. It also decreased the activity of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and the deposition of collagen in the liver. Oral administration of EHT reduced the levels of alpha-smooth muscle actin (alpha-SMA) and the activity of metalloproteinases (MMPs) in rats injured by treatment with CCl(4). In addition, we performed experiments with the rat hepatic stellate cell line HSC-T6 in which we induced the expression of MMP-2 and alpha-SMA with phorbol-12-myristate-13-acetate (PMA). Treating these cells with OA (20microM) or UA (10microM) caused a decrease in the levels of both proteins. Taken together, our data indicate that EHT can efficiently inhibit CCl(4)-induced liver fibrosis in rats. EHT may therefore be a useful functional food for preventing liver fibrosis.

Variation of ursolic acid content in eight Ocimum species from northeastern Brazil

Ursolic acid is a very important compound due to its biological potential as an anti-inflammatory, trypanocidal, antirheumatic, antiviral, antioxidant and antitumoral agent. This study presents the HPLC analysis of ursolic acid (UA) content in eight different Ocimum species: O. americanum L., O. basilicum L, O. basilicum var purpurascens Benth, O. basilicum var. minimum L, O. gratissimum L, O. micranthum Willd, O. selloi Benth. and O. tenuiflorum L. grown in Northeastern Brazil. In these Ocimum species, UA was detected in different yields, with O. tenuiflorum showing the highest content (2.02%). This yield is very significant when compared with other sources of UA.

HPTLC-densitometric method of determination of oleanolic acid in the Lamii albi flos

HPTLC combined with densitometric method was used to determine the content of oleanolic acid in acetone extract from the Lamii albi flos L. The plant extract was separated on Si 60 HPTLC plates and determined with the use of two densitometric methods: measurement of fluorescence and absorbance. The content of oleanolic acid was statistically calculated. In a measurement of absorbance in 1 g of the dry Lamii albi flos L. 1458 microg of oleanolic acid was determined (0.147%). In a fluorescence method in 1 g of the plant material 1516 microg of oleanolic acid was determined (0.149%).

Separation and determination of closely related triterpenic acids by high performance thin-layer chromatography after iodine derivatization

A method based on high performance thin-layer chromatography combined with densitometry for the simultaneous determination of oleanolic and ursolic acids is described. Because of the similarity of chemical structure the prechromatographic derivatization was necessary to separate these triterpenic acids. The samples were treated by 1% iodine solution in chloroform directly on the chromatographic plate and developed with the mobile phase consisting of A (petroleum ether), B (ethyl acetate) and C (acetone) (8.2:1.8:0.1, v/v/v). After drying, the plates were sprayed with 10% (v/v) ethanol solution of sulfuric acid(VI) and heated to 120 degrees C for 3 min. Quantification was performed in absorbance/transmittance mode at a wavelength of 530 nm by using a computer-controlled densitometer Desaga CD 60. The presented method was validated for linearity, precision and accuracy. Correlation coefficient (r(2)>0.99), R.S.D. values (1.4-3.5%), detection limits as well as recovery values (98.4-103.1%) were found to be satisfactory. The method has been successfully applied in the analysis of both triterpenic acids in plant extract.

Ursolic acid ameliorates cognition deficits and attenuates oxidative damage in the brain of senescent mice induced by D-galactose

Ursolic acid (UA), a pentracyclic triterpene, is reported to have an antioxidant activity. Here we assessed the protective effect of UA against the d-galactose (D-gal)-induced neurotoxicity. We found that UA markedly reversed the D-gal induced learning and memory impairment by behavioral tests. The following antioxidant defense enzymes were measured: superoxide dismutases (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR). The content of the lipid peroxidation product malondialdehyde (MDA) was also analyzed. Our results indicated that the neuroprotective effect of UA against D-gal induced neurotoxicity might be caused, at least in part, by the increase in the activity of antioxidant enzymes with a reduction in lipid peroxidation. And UA also inhibited the activation of caspase-3 induced by D-gal. Furthermore, we found that UA significantly increased the level of growth-associated protein GAP43 in the brain of D-gal-treated mice. These results suggest that the pharmacological action of UA may offer a novel therapeutic strategy for the treatment of age-related conditions.

Use of liquid chromatography-atmospheric pressure chemical ionization-ion trap mass spectrometry for identification of oleanolic acid and ursolic acid in Anoectochilus roxburghii (wall.) Lindl

Oleanolic acid (OA) and ursolic acid (UA) are the two important bioactive compounds in Anoectochilus roxburghii (wall) Lindl (A. roxburghii), which has been used as a traditional Chinese medicine. So far, there has been no report to indicate that A. roxburghii contains these two bioactive compounds. It is necessary to develop an effective method to extract and analyze OA and UA in A. roxburghii. In this paper, a quantitative method, consisting of supercritical fluid extraction (SFE) followed by liquid chromatography-atmospheric pressure chemical ionization-ion trap mass spectrometry (LC-APCI-IT-MS) analysis, was developed for identification of OA and UA in A. roxburghii. The extraction was carried out by using CO(2) as the supercritical fluid and ethanol as the modifier before LC separation. The mobile phase used for LC separation consisted of acetic acid (1%, v/v), water (15%, v/v) and methanol (84%, v/v), and the elution was performed at a flow rate of 0.8 ml/min. The mass spectrometer was operated in APCI(+) mode with selected ion monitoring (SIM) to quantify OA and UA at m/z 439.4. Under optimum conditions, the linear responses of OA and UA were obtained in the concentration range of 0.5-80 (r = 0.9992) and 0.5-50 microg/ml (r = 0.9989) with the detection limits of 0.125 and 0.085 microg/ml, respectively. The proposed method has been used for the identification and quantitation of OA and UA in a real A. roxburghii sample.

Determination of free isomeric oleanolic acid and ursolic acid in Pterocephalus hookeri by capillary zone electrophoresis

A rapid capillary zone electophoresis (CZE) method for the quantification of two bioactive terpenes in Pterocephalus hookeri was developed. With beta-cyclodextrin as an additive, excellent resolution for these hydrophobic isomers can be obtained in less than 11 min. Linear calibration range for oleanolic acid was between 15.6 and 1000 microg/ml (r=0.9998), for ursolic acid between 31.2 and 1000 microg/ml (r=0.9992). The limits of detection for oleanolic acid and ursolic acid were 3.4 and 3.8 microg/ml, respectively. The contents of the free oleanolic acid and ursolic acid in P. hookeri were determined with recoveries ranging from 95.2 to 106.0%. The contents of oleanolic and ursolic acids were found to be 0.21 mg/g (RSD 5.49%) and 0.53 mg/g (RSD 3.37%), respectively. After hydrolysis by acid, these values were 1.12 mg/g (RSD 3.29%) and 0.43 mg/g (RSD 3.42%).

Novel and simple nonaqueous capillary electrophoresis separation and determination bioactive triterpenes in Chinese herbs

Three bioactive triterpenes ursolic acid, oleanolic acid and 2alpha,3beta,24-trihydroxy-urs-12-en-28-oic acid were simultaneously separated by nonaqueous capillary electrophoresis (NACE) with methanol:acetonitrile (65:35 v/v) mixture containing 90 mm trishydroxymethylaminomethane (Tris) at an applied voltage of +25 kV and a hydrodynamic injection of 5s. The effect of solvent composition, electrolyte nature and concentration on the electrophoretic behavior of the analytes were systematically studied. Separations were carried out in a fused-silica capillary tube with UV detection at 214 nm. Good separation and correlation coefficients were obtained. Meanwhile, the method was applied to separation and determination the three components in six Chinese herbs extraction. It is concluded that this method could be used for speedy and accurate qualitative and quantitative analysis of bioactive triterpenes in Chinese herbs.

Combinational numeral fingerprint spectra ofGlycyrrhiza and analysis of common peak ratio invariableness in HPLC

To overcome the instability of traditional Chinese medicine (TCM) fingerprint spectra (FPS) and to build up absolute identification standard of TCM, the construction method of combinational numeral fingerprint spectra (CNFPS) was set up. The analysis of invariableness based on CNFPS was carried out. It can be used as absolute quantitative standard to identify the difference of TCM samples. According to this method, the HPLC FPS of components extracted from Glycyrrhiza root samples by ethanol was analyzed. Stable results and accurate quality evaluation were obtained perfectly. The common peak ratio invariableness is an absolute standard in identifying TCM samples, which is better than the similarity method of the FPS.

HPLC quantification of two isomeric triterpenic acids isolated from Mitracarpus scaber and antimicrobial activity on Dermatophilus congolensis

Oleanolic (OA) and ursolic acids (UA) were isolated for the first time from the alcoholic extract of Mitracarpus scaber possessing antimicrobial effects on Dermatophilus congolensis. These two triterpenic acids were also active (MIC 15 microg/ml) on this causative agent of dermatophilosis in African animals. To quantify OA and UA in M. scaber, a new, simple and rapid high-performance liquid chromatography (HPLC) method compatible with MS detection was developed and validated. The mobile phase acetonitrile:H2O (85:15, v/v) was pumped through a C18 octadecylsilyl silica column at a flow rate of 0.6 ml/min and the eluate was monitored at 215 nm. The calibration curves constructed between 0.5 and 10 microg/ml showed linear relationships with good R2 values. The developed method was precise and reproducible with relative standard deviations (RSD) for these two active constituents between 0.22-2.06% (intraday) and 1.61-3.72% (interday) for concentrations from 0.5 to 6 microg/ml. Limits of detection and quantification were, respectively, 0.2 and 0.5 microg/ml.

Determination of oleanolic acid and ursolic acid in cornel by cyclodextrin-modified micellar electrokinetic chromatography

A cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) method was established for the determination of oleanolic acid and ursolic acid in cornel. The two components were separated in the running buffer of 40 mmol/L sodium borate containing 5% methanol, 25 mmol/L SDS and 15 mmol/L hydroxypropyl-beta-cyclodextrin (HP-beta-CD). The applied voltage was 24 kV. The wavelength of detection was 200 nm. The temperature was kept at 25 C. Cinnamic acid was used as the internal standard. The analytical performance of the method was tested with respect to linearity, precision and recovery. The calibration curves were linear in the range of 10.15-243.6 microg/mL, r=0.9993 (oleanolic acid) and 10.07-241.7 microg/mL, r=0.9994 (ursolic acid); the intra-day precision (RSD) was less than 3.7% (oleanolic acid) and 4.1% (ursolic acid); the inter-day precision (RSD) was less than 4.2% (oleanolic acid) and 4.9% (ursolic acid). The limits of detection were 1.6 microg/mL for both components. The method proved to be sensitive, rapid, accurate and suitable for the determination of oleanolic acid and ursolic acid in cornel.

Determination of icariin and metabolites in rat serum by capillary zone electrophoresis: rat pharmacokinetic studies after administration of icariin

A simple and rapid method for determination of icariin (ICA) and its two metabolites, icaritin (ICT) and desmethylicaritin (DICT), by capillary zone electrophoresis has been developed and validated. Optimum separation of ICA, ICT, and DICT was obtained on 43.6 cm x 50 microm capillary using sodium tetraborate (30 mmol/L), monobasic sodium phosphate (50 mmol/L)-acetonitrile (50:50, v/v) (pH 10.0) as running buffer. Carbamazepine (CMP) was used as internal standard (IS). The temperature and voltage were optimized at 25 degrees C and 12 kV, respectively. The limit of detection of ICA was 1.0 mg/L (S/N = 3) by UV detection at 270 nm. The elaborated method was tested in vivo after administration of a single dose of 120 mg ICA/kg to healthy rats. Calculated parameters confirmed usefulness of the method in rat pharmacokinetic studies on ICA.

Recent advances in analysis of Chinese medical plants and traditional medicines

Chinese herbal medicine is gaining increasing popularity worldwide for health promotion and adjuvant therapy. Thus, selective and efficient analytical methods are required not only for quality assurance but also for authentication of the plant material. Applications of both chromatographic and electrophoretic techniques to the analysis of medicinal plants and Chinese traditional medicine preparations over the last 3 years are outlined in this review. The role of chemical fingerprinting is highlighted and a brief survey of determination of toxic components, natural and synthetic adulterants is also included. Moreover, different sample pretreatment and extraction methods are discussed.