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

Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

Triterpenoids widely exist in nature, displaying a variety of pharmacological activities. Determining triterpenoids in different matrices, especially in biological samples holds great significance. High-performance liquid chromatography (HPLC) has become the predominant method for triterpenoids analysis due to its exceptional analytical performance. However, due to the structural similarities among botanical samples, achieving effective separation of each triterpenoid proves challenging, necessitating significant improvements in analytical methods. Additionally, triterpenoids are characterized by a lack of ultraviolet (UV) absorption groups and chromophores, along with low ionization efficiency in mass spectrometry. Consequently, routine HPLC analysis suffers from poor sensitivity. Chemical derivatization emerges as an indispensable technique in HPLC analysis to enhance its performance. Considering the structural characteristics of triterpenoids, various derivatization reagents such as acid chlorides, rhodamines, isocyanates, sulfonic esters, and amines have been employed for the derivatization analysis of triterpenoids. This review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of triterpenoids. Moreover, the limitations and challenges encountered in previous studies are discussed, and future research directions are proposed to develop more effective derivatization methods.

Optimization of Ursolic Acid Extraction in Oil from Annurca Apple to Obtain Oleolytes with Potential Cosmeceutical Application

Ursolic acid (UA) is a plant-derived molecule with relevant anti-aging activity, which makes this molecule a potential functional active ingredient in cosmetic formulations. The main objectives of this study were to optimize the UA extraction process from Annurca apple (AA) with sunflower oil as a lyophilic food-grade solvent using Response Surface Methodology (RSM) to determine the potential cosmetic application of the obtained extract. The results of RSM analysis showed a maximum UA yield of 784.40 ± 7.579 (μg/mL) obtained under the following optimized conditions: sunflower oil as extraction solvent, 68.85 °C as extraction temperature, and 63 h as extraction time. The HPLC-DAD-HESI-MS/MS analysis performed on the extract obtained under these conditions, named Optimized Annurca Apple Oleolyte (OAAO), led to the identification of twenty-three phenolic and terpenoid molecules and the quantification of eight of them. To explore the biological properties of OAAO, the in vitro antioxidant activity was evaluated by DPPH, ABTS, and FRAP assays, resulting in 16.63 ± 0.22, 5.90 ± 0.49, and 21.72 ± 0.68 μmol Trolox equivalent/g extract, respectively. Moreover, the permeation study has shown that OAAO may be considered a safe and functional ingredient in potential cosmetic formulations.

Ursolic acid: a pentacyclic triterpenoid that exhibits anticancer therapeutic potential by modulating multiple oncogenic targets

The world is currently facing a global challenge against neoplastic diseases. Chemotherapy, hormonal therapy, surgery, and radiation therapy are some approaches used to treat cancer. However, these treatments are frequently causing side effects in patients, such as multidrug resistance, fever, weakness, and allergy, among others side effects. As a result, current research has focused on phytochemical compounds isolated from plants to treat deadly cancers. Plants are excellent resources of bioactive molecules, and many natural molecules have exceptional anticancer properties. They produce diverse anticancer derivatives such as alkaloids, terpenoids, flavonoids, pigments, and tannins, which have powerful anticancer activities against various cancer cell lines and animal models. Because of their safety, eco-friendly, and cost-effective nature, research communities have recently focused on various phytochemical bioactive molecules. Ursolic acid (UA) and its derivative compounds have anti-inflammatory, anticancer, apoptosis induction, anti-carcinogenic, and anti-breast cancer proliferation properties. Ursolic acid (UA) can improve the clinical management of human cancer because it inhibits cancer cell viability and proliferation, preventing tumour angiogenesis and metastatic activity. Therefore, the present article focuses on numerous bioactivities of Ursolic acid (UA), which can inhibit cancer cell production, mechanism of action, and modulation of anticancer properties via regulating various cellular processes.

Development, Physical-Chemical Characterization, and Molecular Docking Simulations of Ursolic Acid-Sodium Alginate Complexes

The aim of this study was to fabricate ursolic acid (UA)-sodium alginate (SA) complexes to improve the dissolution rate and antioxidant abilities. The antioxidant activity was evaluated by the DPPH (1,1-diphenyl-2-trinitrophenylhydrazine) assay and the pyrogallol auto-oxidation method. For the optimal composition ratio of UA:SA (1:5, w/w), the cumulative release of UA was about 101.22 ± 1.50% for 180 min. Powder X-ray diffractometry (PXRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) analyses confirmed that the crystallinity of UA was significantly reduced by forming complexes with SA. By Fourier transform infrared spectroscopy (FTIR) and molecular docking simulations, it was observed that the hydroxyl group in UA formed hydrogen bonding with the carbonyl group in SA. The DPPH scavenger activities of the complexes were also increased compared with free UA. The results indicated that SA could serve as a promising carrier for lipophilic functional food ingredients due to improved solubility and antioxidant activity.

Simultaneous Quantification of Ursolic and Oleanolic Acids in Glechoma hederacea and Glechoma hirsuta by UPLC/MS/MS

The content of ursolic acid and oleanolic acid was determined in different plant parts of two Glechoma species, G. hederacea and G. hirsuta. To achieve optimal extraction conditions of ursolic acid and oleanolic acid from plant material, several methods including maceration, heat reflux, Soxhlet, and ultrasonic extraction, as well as various solvents (methanol, dichloromethane, ethyl acetate), were investigated and compared.For the simultaneous quantification of pentacyclic triterpenes in extracts from Glechoma sp., an UPLC-MS/MS was developed and validated. The method exhibited good linearity, precision, and recovery, and it also was simple, specific, and fast. We developed the method for future application in the quality control of plant materials and botanical extracts containing ursolic acid and oleanolic acid. With regard to the triterpene constituents, both G. hederacea and G. hirsuta can be used equally, and the aboveground parts of both species, but the leaves especially, are abundant sources of ursolic acid (7.1 - 7.5 mg/g dry weight [DW]). Dichloromethane as an extractant provided the best extraction efficiency as well as selectivity to obtain Glechoma extracts rich in triterpenes as compared to methanol and ethyl acetate, regardless of the particular extraction technique. Dry dichloromethane extracts from aerial parts of Glechoma sp. obtained by the heat reflux method resulted in products with a high content of UA (17 - 25% w/w) are considered to be convenient and rich sources of this compound.

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.

Quantification of three triterpenic acids in dried rosemary using HPLC-fluorescence detection and 4-(4,5-diphenyl-1H-imidazole-2-yl)benzoyl chloride derivatization

Functional triterpenic acids such as ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA) are representative ingredients in rosemary that may have health benefits. UA, OA and BA in rosemary extracts were derivatized with 4-(4,5-diphenyl-1H-imidazole-2-yl)benzoyl chloride (DIB-Cl) and detected using HPLC-fluorescence (FL). Dried rosemary (50 mg) was ground, added to 3 ml of ethanol, sonicated for 40 min, then the sample solution was added to a mixture of 1% trimethylamine and 1 mM DIB-Cl in acetonitrile. The mixture was settled for 5 min at room temperature, then the DIB-triterpenic acid derivatives were separated using a Wakopak Handy ODS column (250 × 4.6 mm, 6 μm) eluted with 25 mM acetate buffer (pH 4.5)/methanol/acetonitrile (= 8:10:82 v/v/v%). The fluorescence intensity of the eluent was monitored at 365 (λex ) and 490 nm (λem ) and the maximum retention time of the derivatives was 30 min. Calibration curves constructed using rosemary extract spiked with standards showed good linearity (r ≥ 0.997) in the range 2.5-100 ng/ml. The detection limits at 3σ for internal BA, UA and OA peaks in rosemary extract were 0.2, 0.4 and 0.5 ng/ml, respectively. This method was used to quantify BA, UA and OA in commercially available dried rosemary products.

Comparison of Phenols Content and Antioxidant Activity of Fruits from Different Maturity Stages of Ribes stenocarpum Maxim

Differences in the content of nine phenols and the antioxidant capacity of Ribes stenocarpum Maxim (RSM) fruits at different stages of maturity were investigated, and the extraction process of polyphenols from RSM was also optimized using Box-Behnken design method. Results showed that the content of the nine phenols varied considerably at different ripening stages; catechin, chlorogenic acid, coumaric acid, and ferulic acid were abundant in immature fruits but decreased with fruit ripening, whereas the levels of rosemary acid and querctin acid were low in immature fruits and increased with time, reaching the highest value after the fruit was completely mature. The phenols extracted from RSM fruits possessed good antioxidant activities for effective and rapid scavenging of DPPH and ABTS free radicals, as well as intracellular ROS. Analysis of the phenols content at different maturity stages indicated that the unripe fruits had significantly higher polyphenols content than mature fruits. Consequently, unripe fruits possessed higher antioxidant activities. According to the overall results of the extraction process optimization, the selected optimal conditions for extracting polyphenols from RSM were as follows: extraction time, 95 min; solvent concentration, 60%; ratio of sample to solvent, 1:25.

A novel and sensitive method for determining vitamin B3 and B7 by pre-column derivatization and high-performance liquid chromatography method with fluorescence detection

A new labeling reagent for vitamin analysis, 2-amino-10-ethyl acridine ketone (AEAO), has been synthesized and successfully applied to the analysis of vitamin B3 and vitamin B7 in different tea samples. The reaction of AEAO with vitamins could proceed easily and quickly in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) as condensing reagent within 45 min. The derivatives exhibited excellent fluorescence property with excitation and emission wavelengths of 290 nm and 430 nm, respectively. Response surface methodology (RSM) was applied to the optimization of pre-column derivatization. Solid phase extraction with HLB cartridges was used for the extraction and purification of water-soluble vitamins in tea samples. The LODs for vitamin B3 and vitamin B7 were 2.56 and 2.22 ng mL^-1, respectively. The proposed method was successfully applied to the analysis of vitamin B3 and vitamin B7 in different tea samples. The study provided a highly sensitive method for accurate analysis of trace vitamins from natural products.

Optimization of extraction parameters of pentacyclic triterpenoids from Swertia chirata stem using response surface methodology

In the present investigation, pentacyclic triterpenoids were extracted from different parts of Swertia chirata by solid-liquid reflux extraction methods. The total pentacyclic triterpenoids (UA, OA, and BA) in extracted samples were determined by HPTLC method. Preliminary studies showed that stem part contains the maximum pentacyclic triterpenoid and was chosen for further studies. Response surface methodology (RSM) has been employed successfully by solid-liquid reflux extraction methods for the optimization of different extraction variables viz., temperature (X₁ 35-70 °C), extraction time (X₂ 30-60 min), solvent composition (X₃ 20-80%), solvent-to-solid ratio (X₄ 30-60 mlg^-1), and particle size (X₅ 3-6 mm) on maximum recovery of triterpenoid from stem parts of Swertia chirata. A Plackett-Burman design has been used initially to screen out the three extraction factors viz., particle size, temperature, and solvent composition on yield of triterpenoid. Moreover, central composite design (CCD) was implemented to optimize the significant extraction parameters for maximum triterpenoid yield. Three extraction parameters viz., mean particle size (3 mm), temperature (65 °C), and methanol-ethyl acetate solvent composition (45%) can be considered as significant for the better yield of triterpenoid A second-order polynomial model satisfactorily fitted the experimental data with the R² values of 0.98 for the triterpenoid yield (p < 0.001), implying good agreement between the experimental triterpenoid yield (3.71%) to the predicted value (3.79%).

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.

Metabolite identification of ursolic acid in mouse plasma and urine after oral administration by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Ursolic acid (UA), a pentacyclic terpenoid carboxylic acid widely existing in various medicinal plants, has been reported to have multifarious biological activities such as anti-inflammatory, anticancer and antioxidant activities. In this paper, we analyzed the metabolic profile of UA in mice (including plasma and urine) by using ultra-high performance liquid chromatography (UPLC) coupled with a quadrupole time-of-flight (Q/TOF) method. Principal component analysis (PCA) was applied to differentiate the control and experimental groups. Potential biomarkers were filtered by using loading plots followed by further analysis with UPLC-Q/TOF-MS data. The results showed that 3 metabolites in plasma were identified as markers, one of which was UA and the others were UA epoxides, which belonged to phase I metabolites. Additionally, 5 phase II metabolites were tentatively identified in urine through an accurate mass and characteristic fragment ions. These data suggested that the biotransformation of UA undergoes the major metabolic reactions of the phase I metabolic route of olefin oxidation and phase II metabolic routes of glycine conjugation, glutathione conjugation and glucuronidation. This is the first report of analysis and characterization of the metabolites after the oral administration of UA in mice. The proposed metabolic pathways of UA in mice is also raised for the first time. It might provide further understanding of the potential biological mechanism of UA.

First report on metabolism study of ursolic acid (UA) in vivo of mice.

Location of the bioactive pentacyclic triterpene ursolic acid in the membrane. A molecular dynamics study

Ursolic acid (URS), an ursane-representative bioactive pentacyclic triterpene, is a plant secondary metabolite presenting a great number of pharmacological beneficial properties. Due to the prominent hydrophobic character of URS and its high phospholipid/water partition coefficient, some of its possible effects on biological systems might be related to its capacity to interact with and locate into the membrane as well as interact specifically with its components. In this work, we have studied the location and orientation of URS in the membrane by molecular dynamics simulations. At the end of the simulation, URS locates near the surface in vicinity to the phospholipid headgroups but its orientation depends on lipid composition, its final average orientation being a nearly parallel one in POPC but a nearly perpendicular one in POPC/POPE/POPG/PSM/Chol. Furthermore, in the complex lipid system URS seems to interact specifically with POPE, PSM, and Chol excluding POPG from its surroundings, which could lead to phase separation and domain formation. The different disposition of URS in the membrane and its specific interaction with certain lipid types could lead to a significant perturbation of the membrane structure. The important pharmacological activities of URS would rely on the effects it exerts on the membrane structure in general and the existence of specific interactions with specific lipids in particular.

Phytochemistry and Pharmacological Activities of the Genus Swertia (Gentianaceae): A Review

Swertia plants have been considered to be medicinal plants useful for the treatment of various ailments for thousands of years, especially in Asian countries. This is due to the broad variety of chemical compounds that provide multiple ligands for bonding to different endogenous biomacromolecules for patients. Chemical constituents and pharmacological activities of Swertia plants are summarized in this paper. Approximately 419 metabolites and 40 bioactive compounds have been reported from 30 Swertia species, including xanthones, flavonoids, seco-iridiods, iridiods, triterpenoids, alkaloids, volatiles, and other secondary metabolites. The bioactivities of Swertia plants include anticarcinogenic, hepatoprotective, anti-oxidant, hypoglycemic, anthelmintic, antibacterial, antifungal, anti-diabetic, gut, and airways modulatory, metabolizing isozymes inhibitory, neuroprotective, HIV-I reverse transcriptases inhibitory, anticholinergic, and CNS-depressant activities, etc. In addition, biosynthetic pathways of xanthones, and seco-iridiods, two most important secondary metabolites for Swertia, are elucidated. The xanthones biosynthetic pathway is a mixed biosynthetic pathway involved the shikimate and the malonate routes, and the seco-iridoid pathway starts with geraniol derived from IPP which is produced either via the MEP or the MVA pathway. This review will offer a reference for future researches on the protection of natural resources, the investigation of therapeutic basis, new drug development, and so forth. Metabolic pathways of some crucial active compounds were also discussed in this review.

Pharmacokinetic study of ardisiacrispin A in rat plasma after intravenous administration by UPLC-MS/MS

In this work, a sensitive and selective UPLC-MS/MS method for determination of ardisiacrispin A in rat plasma was developed. Cyasterone used as an internal standard (IS) and protein precipitation by acetonitrile-methanol (9:1, v/v) was used to prepare samples. Chromatographic separation was achieved on a UPLC BEH C₁₈ column (2.1 × 100 mm, 1.7 μm) with 0.1% formic acid and acetonitrile as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in positive ion mode; multiple reaction monitoring mode was used for quantification using target fragment ions m/z 1083.5 → 407.1 for ardisiacrispin A and m/z 521.3 → 485.2 for IS. Calibration plots were linear throughout the range 5-2000 ng/mL for ardisiacrispin A in rat plasma. Mean recoveries of ardisiacrispin A in rat plasma ranged from 80.4 to 92.6%. The values of RSD of intra- and inter-day precision were both <11%. The accuracy of the method was between 97.3 and 105.6%. The method was successfully applied to pharmacokinetic study of ardisiacrispin A after intravenous administration in rats.

Reverse Phase-ultra Flow Liquid Chromatography-diode Array Detector Quantification of Anticancerous and Antidiabetic Drug Mangiferin from 11 Species of Swertia from India

Background:

Genus Swertia is valued for its great medicinal potential, mainly Swertia chirayita (Roxb. ex Fleming) H. Karst. is used in traditional medicine for a wide range of diseases. Mangiferin one of xanthoids is referred with enormous pharmacological potentials.

Objective:

The aim of the study was to quantify and compare the anticancerous and antidiabetic drug mangiferin from 11 Swertia species from India. The study also evaluates hierarchical relationships between the species based on mangiferin content using multivariate analysis.

Materials and Methods:

The reverse phase-ultra flow liquid chromatography-diode array detector analyses was performed and chromatographic separation was achieved on a Lichrospher 100, C18e (5 μm) column (250–4.6 mm). Mobile phase consisting of 0.2% triethylamine (pH-4 with O-phosphoric acid) and acetonitrile (85:15) was used for separation with injection volume 20 μL and detection wave length at 257 nm.

Results:

Results indicated that concentration of mangiferin has been found to vary largely between Swertia species collected from different regions. Content of mangiferin was found to be highest in Swertia minor compared to other Swertia species studied herein from the Western Ghats and Himalayan region also. The same was also evident in the multivariate analysis, wherein S. chirayita, S. minor and Swertia paniculata made a separate clade.

Conclusion:

Conclusively, the work herein provides insights of mangiferin content from 11 Swertia species of India and also presents their hierarchical relationships. To best of the knowledge this is the first report of higher content of mangiferin from any Swertia species.

SUMMARY

The present study quantifies and compares mangiferin in 11 species of Swertia from India. The study also evaluates hierarchical relationships between the species based on mangiferin content using multivariate analysis. The mangiferin content was highest in S. minor compared to the studied Swertia species. To the best of our knowledge this is the first report of higher content of mangiferin from Swertia species.

Abbreviations used: LOD: Limit of detection, LOQ: Limit of quantification, RP-UFLC-DAD: Reverse phase-ultra flow liquid chromatography-diode array detector, RSD: Relative standard deviation, SAN: Swertia angustifolia, SAP: Swertia angustifolia var. pulchella, SBI: S. bimaculata, SCH: S. chirayita, SCO: S. corymbosa, SDE: S. densifolia, SDI: S. dialatata, SLA: S. lawii, SMI: S. minor; SNE: S. nervosa, and SPA: S. paniculata

Ursolic acid (UA): A metabolite with promising therapeutic potential

Plants are known to produce a variety of bioactive metabolites which are being used to cure various life threatening and chronic diseases. The molecular mechanism of action of such bioactive molecules, may open up new avenues for the scientific community to develop or improve novel therapeutic approaches to tackle dreadful diseases such as cancer and cardiovascular and neurodegenerative disorders. Ursolic acid (UA) is one among the categories of such plant-based therapeutic metabolites having multiple intracellular and extracellular targets that play role in apoptosis, metastasis, angiogenesis and inflammatory processes. Moreover, the synthetic derivatives of UA have also been seen to be involved in a range of pharmacological applications, which are associated with prevention of diseases. Evidences suggest that UA could be used as a potential candidate to develop a comprehensive competent strategy towards the treatment and prevention of health disorders. The review article herein describes the possible therapeutic effects of UA along with putative mechanism of action.

Accurate Analysis and Evaluation of Acidic Plant Growth Regulators in Transgenic and Nontransgenic Edible Oils with Facile Microwave-Assisted Extraction-Derivatization

Determination of plant growth regulators (PGRs) in a signal transduction system (STS) is significant for transgenic food safety, but may be challenged by poor accuracy and analyte instability. In this work, a microwave-assisted extraction-derivatization (MAED) method is developed for six acidic PGRs in oil samples, allowing an efficient (<1.5 h) and facile (one step) pretreatment. Accuracies are greatly improved, particularly for gibberellin A3 (-2.72 to -0.65%) as compared with those reported (-22 to -2%). Excellent selectivity and quite low detection limits (0.37-1.36 ng mL(-1)) are enabled by fluorescence detection-mass spectrum monitoring. Results show the significant differences in acidic PGRs between transgenic and nontransgenic oils, particularly 1-naphthaleneacetic acid (1-NAA), implying the PGRs induced variations of components and genes. This study provides, for the first time, an accurate and efficient determination for labile PGRs involved in STS and a promising concept for objectively evaluating the safety of transgenic foods.

Simultaneous Determination of Oleanolic and Ursolic Acids in Rat Plasma by HPLC-MS: Application to a Pharmacokinetic Study After Oral Administration of Different Combinations of QingGanSanJie Decoction Extracts

A liquid chromatography-mass spectrometry method has been developed and validated for rapid simultaneous determination of the oleanolic and ursolic acid contents in rat plasma with betulinic acid as the internal standard (IS). The plasma samples were prepared by a liquid-liquid extraction procedure. Chromatographic separation was performed with a Chromasil-C18 column (250 mm × 4.6 mm, i.d. 5 μm) with methanol-water as mobile phase at 1 mL/min. The detection was accomplished under selected-ion-monitoring mode with a negative electrospray ionization interface. Linear calibration curves were obtained between the range of 0.86-421.2 and 0.94-462.0 ng/mL for oleanolic and ursolic acids, with lower limits of quantification at 0.43 and 0.47 ng/mL, respectively. The extraction recovery exceeded 70% in plasma. The intra- and interday precision values were <9.8% with the accuracy as -7.0 to 9.9% at three different QC levels in both cases. The pharmacokinetic behaviors of oral dosage of QingGanSanJie decoctions were then studied in rats following the developed approach. The t1/2 values of the oleanolic and ursolic acids after oral administration of the monarch medicine extract were significantly different (P < 0.05) from other prescription extracts containing different herb pieces with different compatibilities. Bimodal phenomena appeared in every concentration-time curve for the oleanolic and ursolic acids at 3-8 h after administration. The minister, assistant and guide medicines in the formula could prolong the metabolism of the oleanolic and ursolic acids in vivo, providing an experimental basis for the slow onset and long action of the Traditional Chinese Medicine compound.

Quantitative determination of three pentacyclic triterpenes from five Swertia L. species endemic to Western Ghats, India, using RP-HPLC analysis

Aim of this study was to identify pentacyclic triterpenoids betulinic acid (BA), oleanolic acid (OA) and ursolic acid (UA) from five Swertia species endemic to Western Ghats, which are used as substitutes as well as adulterants to Swertia chirayita. Our results indicate that the concentration of active compound vary largely among and within the species from different localities. OA was found in a higher amount in all species compared to BA and UA. From the results, it was clear that BA, OA and UA are present in the endemic species collected from Western Ghats, thus advocating the use of these species as alternate sources to S. chirayita. This in due course may release pressure of exploitation from natural resources of S. chirayita and help to bring it out from an endangered category from conservation point of view.

Development of ultrasonic-assisted closed in-syringe extraction and derivatization for the determination of labile abietic acid and dehydroabietic acid in cosmetics

Two resin acids, abietic acid (AA) and dehydroabietic acid (DHAA), in cosmetics may cause allergy or toxicoderma, but remain inaccurately investigated due to their lability. In this work, an accurate, sensitive, efficient and convenient method, utilizing the ultrasonic-assisted closed in-syringe extraction and derivatization (UCSED) prior to high performance liquid chromatography (HPLC) coupled with fluorescence detection (FLD) and on-line tandem mass spectra (MS/MS), has been developed. Analytes are extracted by acetonitrile (10/1, v/m) in a sealed syringe under safe condition (60°C; 15 min; nitrogen atmosphere) and then in-syringe derivatized by 2-(2-(anthracen-10-yl)-1H-naphtho[2,3-d]imidazol-1-yl) ethyl-p-toluenesulfonate (ANITS) (8-fold, 93°C, 30 min, DMF as co-solvent, K2CO3 as catalyst). In UCSED, derivatization contributes to increase both analytical sensitivity and stability of analytes. Excellent linearity (r2≥0.9991) is achieved in wide range (75-3000 ng/mL (AA); 150-4500 ng/mL (DHAA)). Quite low detection limits (AA: 8.2-10.8 ng/mL; DHAA: 19.4-24.3 ng/mL) and limits of analyte concentration (LOAC) (AA: 30.0-44.5 ng/mL; DHAA: 70.9-86.7 ng/mL) ensure the trace analysis. This method is applied to the analysis of cosmetic samples, including depilatory wax strip, liquid foundation, mascara, eyeliner, eyebrow pencil and lip balm. No additional purification is required and no matrix effect is observed, demonstrating obvious advantages over conventional pretreatment such as solid phase extraction (SPE). Accuracy (RE: -3.2% to 2.51%), precision (RSD: 1.29-2.84%), recovery (95.20-103.63%; 95.51-104.22%) and repeatability (<0.23%; <2.87%) are significantly improved. Furthermore, this work plays a guiding role in developing a reasonable method for labile analytes.

Content variations of triterpenic acid, nucleoside, nucleobase, and sugar in jujube (Ziziphus jujuba) fruit during ripening

Jujube (Ziziphus jujuba) fruit is widely consumed as food and traditional Chinese medicine in Asian countries due to its potential effects for human health. To facilitate selection of the maturity stage providing optimum health benefits, jujube fruits were analysed at six stages of growth (S1-6) for triterpenic acids, nucleosides, nucleobases, and sugars by UHPLC-MS/MS or HPLC-ELSD methods. The content levels of most triterpenic acids and sugars increased with ripening, and reached the highest at S5 and S6, respectively. The accumulation of the cyclic nucleotides (cAMP and cGMP) was mainly in the later stage of ripening (S5-6). Therefore, if taking triterpenic acids as the major quality indicator, S5 should be the ideal time to harvest jujube fruit, and the full ripen stage (S6) maybe the best choice when taking sugars and cyclic nucleotides as the most important components.

Determination of triterpenic acids in fruits by a novel high performance liquid chromatography method with high sensitivity and specificity

A novel and interesting pre-column derivatisation method was developed for the analysis of triterpenic acids by high-performance liquid chromatography (HPLC) with fluorescence detection. Each triterpenic acid produced two HPLC peaks with similar peak areas after derivatising with chiral 1-(9H-carbazol-9-yl) propan-2-yl-methanesulfonate (CPMS), while the fatty acid derivative of CPMS had only one peak. This phenomenon greatly increased the confidence in analyte confirmation. Compound with only one peak or two peaks differing greatly in their peak areas could be excluded from the target compound list. CPMS was compared with five other derivatising reagents, four of which produced only one peak for one triterpenic acid, to study the possible mechanism. Analytes with different behaviours were also studied to better interpret the mechanism. The proposed method also showed the merits of high sensitivity and less sample consumption. It was successfully applied to the analysis of triterpenic acids in fruit peels and flesh. There is no prior report on the two peak phenomenon of triterpenic acids. The information provided in this study will be helpful for those who are also engaged in derivatisation study.

Solid dispersion of ursolic acid in Gelucire 50/13: a strategy to enhance drug release and trypanocidal activity

Solid dispersions (SDs) are an approach to increasing the water solubility and bioavailability of lipophilic drugs such as ursolic acid (UA), a triterpenoid with trypanocidal activity. In this work, Gelucire 50/13, a surfactant compound with permeability-enhancing properties, and silicon dioxide, a drying adjuvant, were employed to produce SDs with UA. SDs and physical mixtures (PMs) in different drug/carrier ratios were characterized and compared using differential scanning calorimetry, hot stage microscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), particle size, water solubility values, and dissolution profiles. Moreover, LLC-MK2 fibroblast cytotoxicity and trypanocidal activity evaluation were performed to determine the potential of SD as a strategy to improve UA efficacy against Chagas disease. The results demonstrated the conversion of UA from the crystalline to the amorphous state through XRD. FTIR experiments provided evidence of intermolecular interactions among the drug and carriers through carbonyl peak broadening in the SDs. These findings helped explain the enhancement of water solubility from 75.98 μg/mL in PMs to 293.43 μg/mL in SDs and the faster drug release into aqueous media compared with pure UA or PMs, which was maintained after 6 months at room temperature. Importantly, improved SD dissolution was accompanied by higher UA activity against trypomastigote forms of Trypanosoma cruzi, but not against mammalian fibroblasts, enhancing the potential of UA for Chagas disease treatment.

Comparison of diagnostic tools with multiplex polymerase chain reaction for pediatric lower respiratory tract infection: a single center study

BACKGROUND/PURPOSE

Acute respiratory tract infections are a leading cause of morbidity and mortality in children worldwide. Most have a viral etiology, with pneumococcus as an important pathogen. This single-center study compared the use of conventional diagnostic tools and two multiplex polymerase chain reaction (PCR) examinations for determining pathogens in lower respiratory tract infections (LRTIs) among children aged <5 years.

METHODS

From July to October 2010, 45 patients aged 2 months to 60 months and diagnosed as having LRTIs were enrolled. Their nasopharyngeal aspirates were evaluated through viral culture and two multiplex PCR examinations. The patients' clinical course, symptoms, signs, and laboratory findings were recorded and analyzed.

RESULTS

Among the 45 patients, 38 (84.4%) had detectable pathogens. Conventional viral and blood cultures had 35.6% positive rate, which increased to 51.1% when the quick antigen tests (Influenza A+B test and respiratory syncytial virus) and urine pneumococcal antigen test were combined. The positive rate further increased to 84.4% when the two multiplex PCR methods were combined. Twelve patients had co-infection, including 10 detected by the multiplex PCR methods. The co-infection rate was 26.7% (12/45).

CONCLUSION

Most LRTIs in children have a viral etiology. Multiplex PCR tests are rapid assays that can increase the diagnostic yield rate and detect slow-growing viruses and can detect more pathogens than conventional viral culture to enable, thereby helping clinicians to provide appropriate and timely treatment.

Microwave-assisted one-step extraction-derivatization for rapid analysis of fatty acids profile in herbal medicine by gas chromatography-mass spectrometry

A rapid and practical microwave-assisted one-step extraction-derivatization (MAED) method was developed for gas chromatography-mass spectrometry analysis of fatty acids profile in herbal medicine. Several critical experimental parameters for MAED, including reaction temperature, microwave power and the amount of derivatization reagent (methanol), were optimized with response surface methodology. The results showed that the chromatographic peak areas of total fatty acids and total unsaturated fatty acids content obtained with MAED were markedly higher than those obtained by the conventional Soxhlet or microwave extraction and then derivatization method. The investigation of kinetics and thermodynamics of the derivatization reaction revealed that microwave assistance could reduce activation energy and increase the Arrhenius pre-exponential factor. The MAED method simplified the sample preparation procedure, shortened the reaction time, but improved the extraction and derivatization efficiency of lipids and reduced ingredient losses, especially for the oxidization and isomerization of unsaturated fatty acids. The simplicity, speed and practicality of this method indicates great potential for high throughput analysis of fatty acids in natural medicinal samples.

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.