Development of a validated liquid chromatographic method for the quality control of Prunellae Spica: determination of triterpenic acids

Synergistic antileishmanial activity of erythrodiol, uvaol, and oleanolic acid isolated from olive leaves of cv. Chemlali

This study aimed to assess the antileishmanial activity of biomolecules obtained from Olea europaea L. leaves and twigs recovered from eight Tunisian cultivars. The extraction was first carried out with 80% methanol, and then the obtained extract was fractionated using three solvents of increasing polarity: cyclohexane (CHX), dichloromethane (DCM) and ethyl acetate (EtOAc). The antileishmanial activity was determined against leishmanial strains responsible for cutaneous, visceral, and mucocutaneous leishmaniasis. The cyclohexane fraction of the leaves of cv. Chemlali from the region of Sidi-Bouzid exhibited the strongest leishmanicidal activity against all the tested leishmanial strains. The inhibition concentrations (IC50) were 16.5, 14.5, and 7.4 μg mL-1 for Leishmania mexicana (cutaneous), Leishmania braziliensis (mucocutaneous), and Leishmania donovani (visceral), respectively. Interestingly, low cytotoxicity was observed on THP-1 cells with selective indexes (SI) ranging from 22.8 to 50.5. HPLC-HRMS and full-house NMR analysis allowed the identification of three triterpenic compounds, oleanolic acid (IC50 = 64.1 μg mL-1), erythrodiol (IC50 = 52.0 µg mL-1), and uvaol (IC50 = 53.8 μg mL-1). Antileishmanial activity of uvaol and oleanolic acid has been previously reported. However, this work constitutes the first report of the antileishmanial activity of erythrodiol which showed combinatorial interaction with uvaol (IC50 = 26.1 μg mL-1) against Leishmania tropica. The mixture of the three compounds, as major ones, exhibited an enhanced activity against Leishmania tropica (IC50 = 16.3 µg mL-1) compared to erythrodiol alone or the combination of uvaol and erythrodiol. This finding is of great importance and needs further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03825-3.

Vulgarisin-type diterpenoids from self-heal (Prunella vulgaris) and their neuroprotective effects against ischemia/reperfusion (I/R) via a mitochondria-related pathway

Self-heal (Prunella vulgaris L.) is a perennial edible plant that is widely distributed across the world and is traditionally consumed as a food additive in soft drink beverages. In this study, to explore the functional components of P. vulgaris, an investigation of its ethanol extracts has been conducted by our group. As a result, twelve (1-12) vulgarisin-type diterpenoids with a special 5/6/4/5-fused ring skeleton, including six new ones (1-6), were obtained. Their structures including the absolute configuration were elucidated based on comprehensive spectroscopic evidence, ECD calculations, as well as single-crystal X-ray diffraction analyses. All the isolates were tested for neuroprotective effects against ischemia/reperfusion (I/R) on primary neuron cells through the oxygen and glucose deprivation and reperfusion (OGD/R) induced injury model. The results showed that all twelve vulgarisin-type diterpenoids possess promising neuroprotective activity at a concentration of 10 μM. Among them, compound 3 can significantly suppress cell apoptosis by regulating Bax/Bcl-2 protein expression and inhibiting cleaved caspase-3 and caspase-9 expression with a western blotting assay. Further research revealed that compound 3 could improve mitochondrial function by inhibiting mitochondrial cytochrome c release, reducing ROS levels, and maintaining the membrane potential. This work firstly reports vulgarisin-type diterpenoids possessing neuroprotective activity. These findings also suggest that daily consumption of P. vulgaris might prevent cerebral disorders via a mitochondria-related pathway.

Comprehensive Review on Different Analytical Techniques for HIV 1- Integrase Inhibitors: Raltegravir, Dolutegravir, Elvitegravir and Bictegravir

The advent of HIV-Integrase inhibitors (IN) has marked a significant impact on the lives of HIV patients. Since the launch of the first anti retro-viral drug "Azidothymidine" to the recent advances of IN inhibitors, about 27.4 million people benefit by antiretroviral therapy (ART). The path had been challenging due to many crossroads, leading to the discovery of newer targets. One such recent ART target is Integrase. Use of Integrase inhibitors has surpassed the usage of all other ART owing to a strong barrier to resistance and have been reported to be the first-line therapy. Raltegravir, Elvitegravir, Dolutegravir and Bictegravir are US FDA approved IN inhibitors. The high usage of ART created an opportunity to study various analytical techniques for IN inhibitors. Hitherto, no review encompassing all IN inhibitors is presented. Herein, this review describes the analytical techniques employed for IN inhibitors estimation and quantification reported in the literature and official compendia. Literature suggests that most studies focus on LC-MS/MS and HPLC methods for drug estimation, and few reports suggest spectrophotometric, spectrofluorimetric and electrochemical methods. Furthermore, the review presents the techniques that describe the quantification of integrase drugs in various matrices. Although, antiretroviral drugs are extensively used but data suggests that limited studies have been conducted for determination of impurity profile and stability. This therefore, presents a scope to detect and validate impurities in order to meet ICH guidelines for their limits and further to improve the quality and safety of antiretroviral drugs.

Uncovering Active Ingredients and Mechanisms of Spica Prunellae in the Treatment of Colon Adenocarcinoma: A Study Based on Network Pharmacology and Bioinformatics

BACKGROUND

As a well-known herb used in the treatment of colon adenocarcinoma (COAD), Spica Prunellae (SP) shows favorable clinical effect and safety in China for many years, but its active ingredients and therapeutic mechanisms against COAD remain poorly understood. Therefore, this study aims to uncover active ingredients and mechanisms of SP in the treatment of COAD using a combined approach of network pharmacology and bioinformatics.

METHODS

A comprehensive approach mainly comprised of target prediction, network construction, pathway and functional enrichment analysis, and hub genes verification was adopted in the current study.

RESULTS

We collected 102 compounds-related genes and 3549 differently expressed genes (DEGs) following treatment with SP, and 64 disease-drug target genes between them were recognized. In addition, a total of 25 active ingredients in SP were identified. Pathway and functional enrichment analyses suggested that the mechanisms of SP against COAD might be to induce apoptosis of colon cancer cells by regulating PI3K-Akt and TNF signaling pathways. Recognition of hub genes and core functional modules was performed by constructing protein-protein interaction (PPI) network, from which TP53, MYC, MAPK8 and CASP3 were found as the hub target genes that might play an important part in therapy for COAD. Subsequently we further compared the differential expression level and assessed the prognostic value of these four hub genes. These result of verification suggested that SP exerted therapeutic effects against COAD via a PPI network involving TP53, MYC, MAPK8 and CASP3.

CONCLUSION

In this study, active ingredients and mechanisms of SP in the treatment of COAD were systematically discussed, which provided the foundation for further experimental studies and might act to promote its appropriate clinical application.

Mechanisms of Spica Prunellae against thyroid-associated Ophthalmopathy based on network pharmacology and molecular docking

BACKGROUND

Thyroid-associated ophthalmopathy (TAO) is an autoimmune inflammatory disorder, which lacks effective treatment currently. Spica Prunellae (SP) is popularly used for its anti-inflammatory and immune-regulating properties, indicating SP may have potential therapeutic value in TAO. Therefore, the purpose of this study is to identify the efficiency and potential mechanism of SP in treating TAO.

METHODS

A network pharmacology integrated molecular docking strategy was used to predict the underlying molecular mechanism of treating TAO. Firstly, the active compounds of SP were obtained from TCMSP database and literature research. Then we collected the putative targets of SP and TAO based on multi-sources databases to generate networks. Network topology analysis, GO and KEGG pathway enrichment analysis were performed to screen the key targets and mechanism. Furthermore, molecular docking simulation provided an assessment tool for verifying drug and target binding.

RESULTS

Our results showed that 8 targets (PTGS2, MAPK3, AKT1, TNF, MAPK1, CASP3, IL6, MMP9) were recognized as key therapeutic targets with excellent binding affinity after network analysis and molecular docking-based virtual screening. The results of enrichment analysis suggested that the underlying mechanism was mainly focused on the biological processes and pathways associated with immune inflammation, proliferation, and apoptosis. Notably, the key pathway was considered as the PI3K-AKT signaling pathway.

CONCLUSION

In summary, the present study elucidates that SP may suppress inflammation and proliferation and promote apoptosis through the PI3K-AKT pathway, which makes SP a potential treatment against TAO. And this study offers new reference points for future experimental research and provides a scientific basis for more widespread clinical application.

Screening for Potential Antibreast Cancer Components From Prunellae Spica Using MCF-7 Cell Extraction Coupled with HPLC-ESI-MS/MS

Prunellae Spica (PS), the dry spikes of Prunella vulgaris L., is a medicinal herb widely distributed in Asia and Europe. As a traditional Chinese medicine, PS has been used for the treatment of mastitis, infectious hepatitis, and hypertension. The oral solution and some compounds (polysaccharide, ursolic acid, and betulinic acid) of PS have been reported to show activities against breast cancer. In this study, Michigan Cancer Foundation-7 (MCF-7) cell extraction coupled with high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) analysis was applied to screen for potential antibreast cancer ingredients from PS. Protocatechuic acid (1), protocatechualdehyde (2), caffeic acid (3), and rosmarinic acid (4) were identified as high-affinity components. The cytotoxic activities of these compounds were evaluated in MCF-7 cells using Cell Counting Kit-8 assay. All the compounds displayed cytotoxicity to MCF-7 cells, but protocatechualdehyde and caffeic acid exhibited significant cytotoxicity with half-maximal inhibitory concentration values of 10.9 μM and 26.8 μM, respectively. This study provides the first report of the successful usage of cell extraction coupled with LC-MS/MS to screen active ingredients from PS. This method can be used as a screening tool for bioactive constituents in natural products.

Fast determination of isomeric triterpenic acids in Osmanthus fragrans (Thunb.) Lour. fruits by UHPLC coupled with triple quadrupole mass spectrometry

Triterpenic acids possess rich biological activity. Due to slight differences in structure and polarity, the simultaneous determination of isomeric triterpenic acids is challenging. In the present work, a simple and effective approach to chromatographic separation of such compounds based on conventional C18 stationary phase with gradient elution was developed, which allowed the simultaneous separation of eleven analytes including euscaphic, arjunic, tormentic, arjunolic, asiatic, pomolic, maslinic, corosolic, oleanolic, ursolic and 2-Epi tormentic acid (internal standard). This approach with mass spectrometric detection and ultrasonic extraction was fast, sensitive and accurate for analyzing isomeric triterpenic acids in O. fragrans fruits with a toal duration of the analytical cycle (including pretreatment) within one hour. The LODs lie in ranges of 0.8-12 ng/mL (30 ng/mL for asiatic and corosolic acid). The developed method was validated and successfully applied in ten batches of O. fragrans fruits, which could reflect the detail content difference of triterpenic acid components.

A metal organic framework polymer monolithic column as a novel adsorbent for on-line solid phase extraction and determination of ursolic acid in Chinese herbal medicine

A metal organic framework (MOF)-polymer monolithic column was prepared by redox initiation using modified MOF and N-methylolacrylamide (NMA) as co-monomers. The obtained monolithic column was characterized by scanning electron microscopy (SEM) and nitrogen adsorption-desorption isotherm measurement. It was used as a solid phase extraction (SPE) absorbent for the online enrichment of ursolic acid (UA) by high performance liquid chromatography. The adsorption amount of UA on the monolith was compared with that of silica gel-C18 adsorbent and the monolith without MOF material. The MOF-polymer monolithic column showed high selectivity and good permeability. Under the optimum conditions for extraction and determination, the calibration equation was y = 79.854× + 0.1939; the linear range was 0.001-0.9 mg/mL; the linear regression coefficient was 0.9993; the limit of detection (LOD) and the limit of quantification (LOQ) were 0.17 μg/mL and 0.57 μg/mL, respectively; the inter-day and intra-day accuracies were <6.44%; the recovery was in the range of 86.52-105.26%. The MOF-polymer monolithic column was successfully used as SPE column for enrichment and determination of UA in Chinese herbal medicine.

Rapid and Sensitive Quantification of Ursolic Acid and Oleanolic Acid in Human Plasma Using Ultra-performance Liquid Chromatography-Mass Spectrometry

Ultra-performance liquid chromatography (UPLC) interfaced with atmospheric pressure chemical ionization mass-spectrometry was used to separate and quantify ursolic acid (UA) and oleanolic acid (OA) in human plasma. UA and OA were extracted from 0.5 mL human plasma using supported liquid extraction and separated utilizing an Acquity UPLC HSS column. The method has been validated for both UA and OA quantitation with a limit of detection of 0.5 ng/mL. The UPLC separations are carried out with isocratic elution with methanol and 5 mM ammonium acetate in water (85:15) as a mobile phase at a flow rate of 0.4 mL/min. The assay was linear from 1 ng/mL to 100 ng/mL for both analytes. The total analysis time was 7 min with the retention times of 3.25 (internal standard), 3.65 (UA) and 3.85 min (OA). Recovery of drug from plasma ranged from 70% to 115%. Analysis of quality control samples at 3, 30 and 80 ng/mL (n = 14) had an intra-day coefficient of variation of 9.9%, 4.3% and 5.5%, respectively. A proof-of-concept study in human patients who consumed apple peels indicates that this analytical method could be applied to clinical studies of UA and/or OA in human subjects.

Spectrum-Effect Relationships Between the Bioactive Ingredient of Syringa oblata Lindl. Leaves and Its Role in Inhibiting the Biofilm Formation of Streptococcus suis

Syringa oblata Lindl. (S. oblata) has been used in herbal medicines for treating bacterial diseases. It is also thought to inhibit Streptococcus suis (S. suis) biofilm formation. However, due to the inherent nature of the complexity in its chemical properties, it is difficult to understand the possible bioactive ingredients of S. oblata. The spectrum-effect relationships method was applied to screen the main active ingredients in S. oblata obtained from Heilongjiang Province based on gray relational analysis. The results revealed that Sub-MICs obtained from 10 batches of S. oblata could inhibit biofilm formation by S. suis. Gray relational analysis revealed variations in the contents of 15 main peaks and rutin was discovered to be the main active ingredient. Then, the function of rutin was further verified by inhibiting S. suis biofilm formation using crystal violet staining. Computational studies revealed that rutin may target the chloramphenicol acetyltransferase protein in the biofilm formation of S. suis. In conclusion, this study revealed that the spectrum-effect relationships and computational studies are useful tools to associate the active ingredient with the potential anti-biofilm effects of S. oblata. Here, our findings would provide foundation for the further understanding of the mechanism of S. oblata intervention in biofilm formation.

Characteristics, Biological Properties and Analytical Methods of Ursolic Acid: A Review

Ursolic acid (UA) is a naturally occurring triterpenoid which is a promising candidate for the development of new therapeutic approaches and for the prevention and treatment of several diseases owing to its pharmacological importance. However, its low solubility in aqueous medium affects its therapeutic application. Several strategies have been used to overcome this obstacle. In this study, the incorporation of UA in to different drug delivery systems was found to be highly efficient. In addition, important investigations were performed about methods for qualitative and quantitative analyses of UA in various raw materials, including plants, biological fluids, and drug delivery systems, were investigated. Most recently high performance liquid chromatography coupled with various detectors, gas chromatography-mass spectrometry and capillary electrophoresis were used for this purpose. Thus, this review was performed to evaluate the biological effects of UA demonstrated thus far as well as the currently used, delivery systems and analytical methods.

Spica Prunellae extract suppresses the growth of human colon carcinoma cells by targeting multiple oncogenes via activating miR-34a

Spica Prunellae is the spike of the herb Prunella vulgaris L. in traditional Chinese medicine which is often used for the treatment of various cancers including colorectal cancer. In the present study, we found that a key tumor suppressor, microRNA-34a (miR-34a) is involved in the antitumor activity for Spica Prunellae. Human colon carcinoma HCT-8 cells treated with an ethanol extract of Spica Prunellae (EESP) had significantly decreased cell proliferation and viability, in a dose-dependent manner. Flow cytometry analysis with Annexin V/PI staining analysis revealed that EESP treatment could induce apoptosis of HCT-8 cells. The level of miR-34a was upregulated in HCT-8 cells following EESP treatment, whereas expression levels of its target genes Notch1, Notch2 and Bcl-2 were downregulated. Inhibition of miR-34a rescued the expression of these target genes. These results revealed that Spica Prunellae can suppress the growth of HCT-8 cells by targeting Notch1, Notch2 and Bcl-2 via activation of miR-34a.

Comprehensive chemical profiling of Pinellia species tuber and processed Pinellia tuber by gas chromatography-mass spectrometry and liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry

A comprehensive profiling method was established for the determination of various chemicals in Pinellia (P.) ternata and pedatisecta species. The profiling method comprises a fast ultrasonic extraction with various solvents, followed by GC-MS and LC-APCI-MS analysis. A total of 73 polar components as trimethylsilyl (TMS) derivatives were detected in methanol extract by GC-MS. The main components of the P. species were profiled as several kinds of fatty acids, amino acids, nucleic acids, carbohydrates, and phenolic compounds. The hexane extract was analyzed by LC-APCI-MS for the lipid profiling. A total of 35 lipid constituents [fatty acids and their esters, mono-, di-, and tri-acylglycerols] and four phytosterols were observed and tentatively characterized by LC-APCI-MS/MS. Among the phytochemicals detected in the hexane extract, triacylglycerols (TAGs) as the major component were identified by LC-APCI-MS and MS/MS. Based on the identified components, a significant difference in the chemical compositions of P. species tuber and processed P. ternata was found that the complete disappearance of TAGs and a considerable decrement of sucrose were observed in processed P. ternata. Furthermore, the degradation mechanism for TAGs in the presence of alum solution is suggested to occur during the processing P. ternata. Malic acid was found to be a characteristic compound for the classification of P. ternata and pedatisecta with different geographic origins. Based on the validated GC/MS method, twenty-four P. ternata, processed P. ternata and P. pedatisecta samples were profiled to measure the overall abundance of specific groups of compound and to identify diagnostic compounds. In addition, principal component analysis (PCA) on the GC/MS profiling data revealed a clear classification of P. species samples. In this study, the full chemical complement was for the first time reported for quality evaluation of P. species. The method can be usefully applied for phytochemical analysis of related herbal medicines.

Simultaneous determination of six triterpenic acids in some Chinese medicinal herbs using ultrasound-assisted dispersive liquid-liquid microextraction and high-performance liquid chromatography with fluorescence detection

A novel analytical method was developed for simultaneous determination of six triterpenic acids using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) follow by high-performance liquid chromatography (HPLC) with fluorescence detection. Six triterpenic acids (ursolic acid, oleanolic acid, betulinic acid, maslinic acid, betulonic acid and corosolic acid) were extracted by UA-DLLME using chloroform and acetone as the extraction and disperser solvents, respectively. After the extraction and nitrogen flushing, the extracts were rapidly derivatized with 2-(12,13-dihydro-7H-dibenzo[a,g]carbazol-7-yl)ethyl4-methylbenzenesulfonate. The main experimental parameters affecting extraction efficiency and derivatization yield were investigated and optimized by response surface methodology (RSM) combined with Box-Behnken design (BBD). The limits of detection (LODs) and the limits of quantification (LOQs) were in the range of 0.95-1.36 ng mL(-1) and 3.17-4.55 ng mL(-1), respectively. Under the optimum conditions, the method has been successfully applied for the analysis of triterpenic acids in six different traditional Chinese medicinal herbs.

Efficiency and selectivity of triterpene acid extraction from decoctions and tinctures prepared from apple peels

Background:

This study assessed the extraction efficiency of ursolic (UA) and oleanolic acids (OA), as well as the total phenols in aqueous and hydroethanolic extracts of dry apple peels at room temperature.

Materials and Methods:

After running preliminary assays on decoctions and tinctures (ethanol: water 7:3 v/v), the extracts from dried apple (cv. Fuji) peels were obtained by static maceration over varied intervals (2 to 180 days). The UA and OA content in the extracts was quantified by High Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) with a reversed phase column and isocratic elution (CH₃CN/H₂O/H₃PO₄) against calibration curves (R² > 0.9995). The total phenol content in the extracts was evaluated spectrophotometrically at 760 nm using the Folin-Ciocalteau method referencing gallic acid.

Results:

UA and OA in the hydroethanolic extracts ranged from 3.63-6.12 mg/g and 2.12-3.30 mg/g, corresponding to 1.72-3.07 and 1.00-1.66 mg/g in the raw material, respectively. Higher values of triterpene acid content corresponded to maceration periods of 10 or 30 days. The residual phenol and polyphenol content ranged from 6.97 to 11.6 mg/g. The UA and OA yields, as well as the total phenol content, versus the maceration time were plotted in Control Charts within confidence intervals (95%) and were unaffected during the assayed period.

Conclusion:

Apple peel tinctures from 10% solids obtained at room temperature exhibited the highest content of triterpene acids when employing a maceration period of 10 to 30 days. Extracts prepared using this procedure contained an average of 7.33 mg/g of total triterpene acids and 10.6 mg/g phenolic compounds. These results establish supporting data for apple peel tinctures and their derived phytopharmaceuticals that are standardized on the ursolic-oleanolic acid content.

Determination of Triterpenic Acids and Screening for Valuable Secondary Metabolites in Salvia sp. Suspension Cultures

Plant in vitro cultures are a prospective alternative for biochemicals production, for example the triterpenes oleanolic and ursolic acid present in plants and cell cultures of Salvia sp. Our objective was to develop a suitable analysis protocol for evaluation of triterpenic acid yield in plant raw material and in vitro cultures supporting selection processes. Moreover, valuable bioactive compounds had to be revealed. Thus, different strategies enhancing the separation for a sensitive and effective HPLC-UV method were investigated and the developed method was validated for linearity, precision, accuracy, limits of detection and quantification. A baseline separation of these isomers enabled detection limits of below 0.4 μg/mL and quantification limits of about 1.2 μg/mL. Over the tested concentration range a good linearity was observed (R2 > 0.9999). The variations in the method were below 6% for intra- and inter-day assays of concentration. Recoveries were between 85–98% for both compounds using ethanol as extraction solvent. Additionally, metabolite profiling of cell suspension culture extracts by GC-MS has shown the production variability of different plant metabolites and especially the presence of plant phenols and sterols. These studies provide a method suitable for screening plant and cell culture productivity of triterpenic acids and highlighted interesting co-products of plant cell cultures.

Analysis on fat-soluble components of sinapis semina from different habitats by GC-MS

A simple and rapid gas chromatography/mass spectrometry (GC/MS) analysis method was developed for the determination of fat-soluble parts of sinapis semina. Four major compounds were chosen as marker compounds to evaluate the method. Various extraction techniques were evaluated and the greatest efficiency was observed with sonication extraction using diethyl ether. The method was valuated as follows: acceptable apparatus suitability was obtained by testing the resolutions, tailing factors and theoretical plate number of the marker compounds; the precision and reproducibility, expressed as relative standard deviation (RSD), fell within the prescribed limits. Eight samples of sinapis semina collected from markets in Xi'an were monitored by using the method. The fingerprints of those samples were analyzed by hierarchical cluster analysis (HCA) similarity analysis. The result indicated that the combination of fingerprint and HCA could be used to analyze sinapis semina from different habitats.

A simple GC-MS method for the screening of betulinic, corosolic, maslinic, oleanolic and ursolic acid contents in commercial botanicals used as food supplement ingredients

The occurrence of triterpene pentacyclic acids in plants is extensive, but little is known about their availability in commercial extracts. A simple GC-MS method for the simultaneous determination of betulinic, corosolic, maslinic, oleanolic and ursolic acids was developed and applied to 38 different commercial plant extracts sold as ingredients for dietary supplements. A suitable protocol was set up to perform routine control of a diverse array of samples with different botanical, chemical and physical characteristics. Remarkable quantities of corosolic acid were found in dried extracts from aerial parts of Lagerstroemia speciosa and Ortosiphon stamineus (14233 and 1132 mg/kg, respectively), while oleanolic acid was abundant in O. stamineus and Crataegus monogyna flowers (2774 and 2339 mg/kg); ursolic was identified in O. stamineus, C. monogyna, L. speciosa and Arctostaphylos uva-ursi leaves (7773, 4165, 2108 and 1034 mg/kg). Only L. speciosa was rich in maslinic acid (4958 mg/kg), while minor amounts of betulinic acid (257 and 80 mg/kg) were detected in L. speciosa and C. monogyna extracts. Lower quantities of triterpenic acids were identified in dried extracts of Harpagophyton procumbens root, propolis, Punica granatum root, Styrax benzoin, Vaccinium myrtillus fruits and Vitis vinifera seeds. Decoctions and fluid extracts lacked or contained very low amounts of triterpenic acids. Results are discussed in terms of quality and safety of these ingredients.

Characterization of Yew Tree (Taxus) Varieties by Fingerprint and Principal Component Analyses

The composition of varieties of Taxus growing in Estonia was analyzed by capillary electrophoresis with diode array detection (CE-DAD) for the separation of phenolic compounds, and by high performance liquid chromatography-mass spectrometry (HPLC-MS) for the determination of taxoids. The main purpose of this study was the chemotaxonomic differentiation of varieties of Taxus by using data from these analyses. Fingerprints scanned at 214 nm on the basis of CE separation at pH 9.3 were used to characterize seven varieties of yew. The contents of four key taxoids (10-deacetylbaccatin, baccatin III, cephalomannine and paclitaxel) in six Taxus varieties were comparatively determined by HPLC-MS. The set of electropherograms/chromatograms of the various Taxus extracts were subjected to principal component analysis (PCA), using the peak areas of 16 phenolic compounds and 14 taxoids as characteristics. The formation of distinct clusters in accordance with botanical classification proves the suitability of PCA for differentiating varieties of Taxus.

Towards an efficient protocol for the determination of triterpenic acids in olive fruit: a comparative study of drying and extraction methods

INTRODUCTION

Triterpenic acids, such as maslinic acid and oleanolic acid, are commonly found in olive fruits and have been associated with many health benefits. The drying and extraction methods, as well as the solvents used, are critical factors in the determination of their concentration in plant tissues. Thus, there is an emerging need for standardisation of an efficient extraction protocol that determines triterpenic acid content in olive fruits.

OBJECTIVE

To evaluate common extraction methods of triterpenic acids from olive fruits and to determine the effect of the drying method on their content in order to propose an optimum protocol for their quantification.

METHODOLOGY

The efficacy of different drying and extraction methods was evaluated through the quantification of maslinic acid and oleanolic acid contents using the reversed-phase HPLC technique.

RESULTS

Data showed that ultrasonic assisted extraction with ethanol or a mixture of ethanol:methanol (1:1, v/v) resulted in the recovery of significantly higher amounts of triterpenic acids than other methods used. The drying method also affected the estimated triterpenic acid content; frozen or lyophilised olive fruit material gave higher yields of triterpenic acids compared with air-dried material at both 35°C and 105°C.

CONCLUSION

This study provides a rapid and low-cost extraction method, i.e. ultrasonic assisted extraction with an eco-friendly solvent such as ethanol, from frozen or lyophilised olive fruit for the accurate determination of the triterpenic acid content in olive fruit.

Liquid chromatography tandem mass spectrometry determination of chemical markers and principal component analysis of Vitex agnus-castus L. fruits (Verbenaceae) and derived food supplements

A validated analytical method for the quantitative determination of seven chemical markers occurring in a hydroalcoholic extract of Vitex agnus-castus fruits by liquid chromatography electrospray triple quadrupole tandem mass spectrometry (LC/ESI/(QqQ)MSMS) is reported. To carry out a comparative study, five commercial food supplements corresponding to hydroalcoholic extracts of V. agnus-castus fruits were analysed under the same chromatographic conditions of the crude extract. Principal component analysis (PCA), based only on the variation of the amount of the seven chemical markers, was applied in order to find similarities between the hydroalcoholic extract and the food supplements. A second PCA analysis was carried out considering the whole spectroscopic data deriving from liquid chromatography electrospray linear ion trap mass spectrometry (LC/ESI/(LIT)MS) analysis. High similarity between the two PCA was observed, showing the possibility to select one of these two approaches for future applications in the field of comparative analysis of food supplements and quality control procedures.

Determination of oleanolic and ursolic acid in Chinese herbs using HPLC and γ-CD as mobile phase modifier

To separate and determine oleanolic acid and ursolic acid, a rapid and accurate HPLC using γ-CD as the mobile phase additive was developed. The effect of CD nature and concentration, and the acidity of the mobile phase on the chromatographic behavior of two bioactive triterpenes were systematically studied. Two bioactive triterpenes were completely separated (R = 3.11) on a Kromasil(®) C(18) column (150×4.6 mm id, 5 μm) with the mobile phase consisting of acetonitrile/0.1% phosphoric acid with 2 mM γ-CD as the mobile phase modifier (60:40, v/v). The flow rate was set at 1.0 mL/min and the eluent was detected at 210 nm for two bioactive triterpenes. The linearity of the method was excellent (r=0.9999) over the studied range of 6-300 μg/mL for oleanolic acid, and 12-600 μg/mL for ursolic acid. The LOD and LOQ were 1.5 and 5.0, 1.0 and 3.0 μg/mL for oleanolic acid and ursolic acid, respectively. The optimized method was successfully applied to separate and determine two bioactive triterpenes in five Chinese herbs. It is concluded that this method could be used for rapid and accurate qualitative and quantitative analysis of the two bioactive triterpenes in Chinese herbs.

Development of a new HPLC method with precolumn fluorescent derivatization for rapid, selective and sensitive detection of triterpenic acids in fruits

Triterpenic acids are widespread in plants and have multiplicity of biological properties. Unfortunately the method for accurate analysis of these compounds remains poorly investigated. This study proposed a highly sensitive and selective precolumn derivatization method for accurate determination of five triterpenic acids (betulinic acid, betulonic acid, maslinic acid, ursolic acid and oleanolic acid) in fruits using acridone-9-ethyl-p-toluenesulfonate (AETS) as fluorescent labeling reagent by HPLC with fluorescence detection (FLD). Response surface methodology was employed to optimize the derivatization reaction, ensuring the sufficient labeling of the analyzed components. The rapid separation of five triterpenic acids could be achieved in as little as 16 min. This developed method offered the exciting detection limits of 1.68-2.04 ng/mL. When applied to several popular fruits in China, it revealed satisfactory applicability and reproducibility. This developed method also exhibits powerful potential for accurate detection of triterpenic acids from other foodstuffs and nature products.

Highly sensitive and selective pre-column derivatization high-performance liquid chromatography approach for rapid determination of triterpenes oleanolic and ursolic acids and application to Swertia species: optimization of triterpenic acids extraction and pre-column derivatization using response surface methodology

Oleanolic acid (OA) and ursolic acid (UA) are the ubiquitous triterpenic acids in plant kingdom and have multiple biological effects. In the present study, a highly sensitive and selective method using a dual-sensitive probe 2-(5-benzoacridine)ethyl-p-toluenesulfonate (BAETS) as pre-column labeling reagent has been developed for rapid determination of the triterpenes OA and UA by HPLC with fluorescence detection (FLD) and online mass spectrometry identification. Response surface methodology as an efficient tool was employed to optimize the ultrasonic-assisted extraction of triterpenic acids from Swertia plants and the pre-column derivatization reaction, respectively, which ensured the highest triterpenic acids recoveries within the shortest extraction time and the sufficient labeling of the analyzed components. Fast separation of the isomers OA and UA could be achieved on a Hypersil BDS C8 column within 7 min. Both of OA and UA gave the good correlation coefficients of 0.9999. This developed method offered the satisfactory detection limits of 1.10 and 1.30 ng mL(-1) for UA and OA, respectively. When applied to Swertia species, it showed good reproducibility.

Quality control of Pulsatilla koreana based on the simultaneous determination of triterpenoidal saponins by HPLC-ELSD and principal component analysis

INTRODUCTION

Pulsatilla koreana Nakai, with triterpenoidal saponins as its main pharmacological effective compounds, is known to have several biological activities, including hypoglycaemic, antitumour, cognition-enhancing, neuroprotective, cytotoxic and antiangiogenic activities. However, few analytical methods have been reported on the quality assessment of P. koreana roots.

OBJECTIVE

To establish a high-performance liquid chromatography coupled with evaporative light scattering detection for the simultaneous determination of five triterpenoidal saponins, including pulsatilloside E (1), pulsatilla saponin H (2), anemoside B4 (3), hederacolchiside E (4) and cussosaponin C (5) in P. koreana.

METHODOLOGY

The chromatographic separation was performed on a Shiseido CapCell PAK C18 analytical column efficiently using gradient elution with acetonitrile and water.

RESULTS

All calibration curves showed excellent linear regressions (R(2) > 0.9996) within the range of tested concentrations. The intra- and inter-day variations were below 4.78% in terms of RSD. The recoveries were 94.82-102.97% with RSD of 0.27-3.92% for spiked P. koreana samples.

CONCLUSION

The validated method was successfully used for the analysis of five saponins in P. koreana from different locations. Moreover, the different samples were clustered in accordance with contents of triterpenoidal saponins based on aglycon type by a principal component analysis.

Rosmarinic acid in Prunella vulgaris ethanol extract inhibits lipopolysaccharide-induced prostaglandin E2 and nitric oxide in RAW 264.7 mouse macrophages

Prunella vulgaris has been used therapeutically for inflammation-related conditions for centuries, but systematic studies of its anti-inflammatory activity are lacking and no specific active components have been identified. In this study, water and ethanol extracts of four P. vulgaris accessions were applied to RAW 264.7 mouse macrophages, and the ethanol extracts significantly inhibited lipopolysaccharide (LPS)-stimulated prostaglandin E2 (PGE2) and nitric oxide (NO) production at 30 microg/mL without affecting cell viability. Extracts from different accessions of P. vulgaris were screened for anti-inflammatory activity to identify accessions with the greatest activity. The inhibition of PGE2 and NO production by selected extracts was dose-dependent, with significant effects seen at concentrations as low as 10 microg/mL. Fractionation of ethanol extracts from the active accession, Ames 27664, suggested fractions 3 and 5 as possible major contributors to the overall activity. Rosmarinic acid (RA) content in P. vulgaris was found to independently inhibit inflammatory response, but it only partially explained the extracts' activity. LPS-induced cyclooxygenase-2 (COX-2) and nitric oxide synthase (iNOS) protein expression were both attenuated by P. vulgaris ethanol extracts, whereas RA inhibited only COX-2 expression.