Micromorphology and Chemical Studies on Anacardium occidentale L. Stem Bark as an Herbal Medicine

The red and white types of Anacardium occidentale L. stem barks (AoB) are used in the Community of Portuguese Language Countries, including Portugal, to make traditional herbal preparations for the treatment of diabetes. This work aims to obtain the macroscopic, micromorphological, chemical, and purity data necessary to use both types of AoBs as medicinal plants safely. Macroscopically, a brown inner (red AoB) or a dark-brown inner surface (white AoB) was observed. Light and scanning electron microscopy showed that sclereid cells with thin cell walls were significantly larger (p < 0.001) in red AoB than in white AoB, but calcium oxalate druses and starch grain areas were significantly larger (p < 0.001) in white AoB than in red AoB. The chromatographic profiles (thin-layer chromatography and high-performance liquid chromatography) of both types of AoBs were characterized by the presence of gallic and protocatechuic acids and other phenolic derivatives. The condensed tannins were the major secondary metabolites class (143.69 ± 4.67 mg and 73.79 ± 4.46 mg catechin equivalents/g AoB in red and white types, respectively). The loss on drying and the total ash were, respectively, 7.07 ± 0.16% and 2.31 ± 0.18% in red AoB and 6.58 ± 0.16% and 1.94 ± 0.14% in white AoB. The obtained data are helpful in ensuring the quality of AoB as raw material for the pharmaceutical market.

Establishing a chromatographic fingerprint using tandem UV/charged aerosol detection and similarity analysis for Shengmai capsule: A novel method for natural product quality control

INTRODUCTION

Shengmai San, a well-known traditional Chinese medicine formula, is used to treat coronary heart diseases and myocardial infarction. The complex composition and complicated mechanism of the Shengmai preparations bring a significant challenge in the development of a suitable quality control method.

OBJECTIVES

This work aims to establish a chromatographic fingerprinting method and propose a weighting algorithm for application in fingerprint similarity analysis to ensure consistent quality of the Shengmai capsule.

METHODOLOGY

A chromatographic fingerprint method was established using tandem UV/charged aerosol detection (CAD) for Shengmai capsule quality control. After method verification, the developed method was applied to analyze 15 batches of the samples. Then a weighting algorithm of the fingerprint peak was proposed and used for the fingerprint similarity analysis.

RESULTS

An HPLC-UV/CAD fingerprint method was successfully developed for the Shengmai capsules. Chromatographic conditions of the HPLC-UV/CAD method were optimized with a definitive screening design, and the optimized ranges of operating parameters were obtained with a Monte Carlo simulation method. The combined use of the proposed weighting algorithm and similarity analysis on fingerprint data improves the sensitivity of distinguishing batch-to-batch quality differences.

CONCLUSION

The developed HPLC-UV/CAD fingerprint method is robust, reliable, and efficient. The proposed weighting algorithm combined with similarity analysis is promising and meaningful for the quality consistency assessment of HPLC-UV/CAD fingerprints.

[Quality value transmitting of substance benchmarks of Zhuru Decoction]

A total of 18 batches of Zhuru Decoction samples were prepared. Chromatographic fingerprints were established for Zhuru Decoction and single decoction pieces, the content of which was then determined. The extraction rate ranges, content, and transfer rate ranges of puerarin, liquiritin, and glycyrrhizic acid, together with the common peaks and the similarity range of the fingerprints, were determined to clarify key quality attributes of Zhuru Decoction. The 18 batches of Zhuru Decoction samples had 25 common peaks and the fingerprint similarity higher than 0.95. Puerariae Lobatae Radix, Glycyrrhizae Radix et Rhizoma, and Zingiberis Rhizoma Recens had 21, 3, and 1 characteristic peaks, respectively. The 18 batches of samples showed the extraction rates within the range of 18.45%-25.29%. Puerarin had the content of 2.20%-3.07% and the transfer rate of 38.5%-45.9%; liquiritin had the content of 0.24%-0.85% and the transfer rate of 15.9%-37.5%; glycyrrhizic acid had the content of 0.39%-1.87% and the transfer rate of 16.2%-32.8%. In this paper, the quality value transmitting of substance benchmarks of Zhuru Decoction was analyzed based on chromatographic fingerprints, extraction rate, and the content of index components. A scientific and stable method was preliminarily established, which provided a scientific basis for the quality control and formulation development of Zhuru Decoction.

Gas Chromatographic Fingerprint Analysis for the Comparison of Seized Cannabis Samples

Cannabis sativa L. is widely used as recreational illegal drugs. Illicit Cannabis profiling, comparing seized samples, is challenging due to natural Cannabis heterogeneity. The aim of this study was to use GC–FID and GC–MS herbal fingerprints for intra (within)- and inter (between)-location variability evaluation. This study focused on finding an acceptable threshold to link seized samples. Through Pearson correlation-coefficient calculations between intra-location samples, ‘linked’ thresholds were derived using 95% and 99% confidence limits. False negative (FN) and false positive (FP) error rate calculations, aiming at obtaining the lowest possible FP value, were performed for different data pre-treatments. Fingerprint-alignment parameters were optimized using Automated Correlation-Optimized Warping (ACOW) or Design of Experiments (DoE), which presented similar results. Hence, ACOW data, as reference, showed 54% and 65% FP values (95 and 99% confidence, respectively). An additional fourth root normalization pre-treatment provided the best results for both the GC–FID and GC–MS datasets. For GC–FID, which showed the best improved FP error rate, 54 and 65% FP for the reference data decreased to 24 and 32%, respectively, after fourth root transformation. Cross-validation showed FP values similar as the entire calibration set, indicating the representativeness of the thresholds. A noteworthy improvement in discrimination between seized Cannabis samples could be concluded.

Study on Gas Chromatographic Fingerprint of Essential Oil from Stellera chamaejasme Flowers and Its Repellent Activities against Three Stored Product Insects

The objective of this study was to establish the chromatographic fingerprints of the essential oil (EO) from Stellera chamaejasme flowers collected from various natural sites by gas chromatography (GC) combined with chemometric methods. The EO was obtained by hydrodistillation, and its chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). Most components were identified as ketones and the relatively high-content components were fitone (38.973%), n-hentriacontane (5.807%), myristic acid (4.944%) and phytol (3.988%). In addition, the repellent activities of the EO from S. chamaejasme flowers and its four main chemical compounds were evaluated against three stored product pests (Tribolium castaneum, Lasioderma serricorne, Liposcelis bostrychophila) for the first time. In this work, the EO and the four chemical compounds showed a repellent effect against three storage pests after 2 and 4 h exposure. The experimental method and repellent activity of S. chamaejasme flower EO could provide a basis for the development of botanical pesticide and the utilization of the rich plant resources of S. chamaejasme in the future.

[Establishment of chromatographic fingerprint of Squama Manis and its applications in animal source identification and quality grade discrimination]

Squama Manis, or "Chuanshanjia" in Chinese, is a traditional Chinese medicine (TCM) for promoting blood circulation and reducing swelling and discharge; the only animal source used in TCM is the scales of Manis pentadactyla. However, in today's pharmaceutical market, there are many scales from other species of the same genus that are difficult to distinguish from Squama Manis. High-quality and low-quality scales are also severely confused. To solve the above problems, various analytical methods have been developed, such as thin-layer chromatography, mass spectrometry and DNA detection. Owing to their low resolving ability, high equipment cost, and inconvenient operation, none of these methods are appropriate for routine identification of Squama Manis. A chromatographic fingerprint can comprehensively reflect the synergic action of multiple chemical compositions in TCM and has been widely used for the quality control of TCM. In the present study, we established a fingerprint of Squama Manis and explored its feasibility in identifying the origin and quality grade of scales. First, Squama Manis powder was hydrolyzed by hydrochloric acid (1 mol/L). Next, the extract was analyzed on a Symmetry 300 C18 column by linear gradient elution, using 0.1% trifluoroacetic acid (v/v) in water and 0.1% trifluoroacetic acid (v/v) in acetonitrile as the mobile phase and 280 nm as the detection wavelength. The established method was systematically validated, demonstrating good precision, repeatability and sample stability (relative standard deviation (RSD)<5%). Subsequently, samples of different sources and quality grades were distinguished by similarity evaluation and discrimination analysis based on the fingerprint data. In the similarity evaluation, the reference fingerprint was defined as the average fingerprint of twelve first-class samples, and seventeen chromatographic peaks were identified as common peaks. Similarities between the reference fingerprint and fingerprints with different base sources and quality grades were calculated using the absolute area of common peaks as original data. The similarities between Squama Manis and scales from other animals were all less than 0.776, while the similarities between Squama Manis of different grades overlapped significantly, varying from 0.988 to 0.996 for first-class samples and 0.950 to 0.995 for general samples. The results reflected the feasibility of similarity evaluation for discriminating base source and its limitation in the distinguishing between quality grades. Nonetheless, first-class scales showed higher average similarity and lower RSD than general scales, which indicates some level of revelation between fingerprint similarity and quality grade. Thus, a better algorithm or discriminant model is required to distinguish between quality grades. Therefore, a supervised chemometric technique, kernel-based support vector machine (SVM), was applied to construct predictive models. The SVM is a common discriminant model that classifies samples by constructing a separate hyperplane in n-dimensional space, maximizing the margin between classes. Combination with a kernel function can effectively avoid "dimension disaster" when dealing with nonlinear data. In the model, the quality grade was defined as a sample label, and the absolute peak areas constituted the data matrix. Verified by 10-fold cross-validation, the unbiased prediction accuracy was up to 95.83%. The predicted results were highly consistent with the actual classifications. The results indicate the high feasibility of the established model for determining quality grade, as it performed significantly better than the similarity evaluation. Samples from batches A and B were completely discriminated and only two samples from batch S were incorrectly classified. Given the batch bias, we believe that model error may have been caused by man-made tag errors rather than the model itself. In conclusion, we established a chromatographic fingerprint for Squama Manis quality analysis and demonstrated its feasibility in animal source identification and quality determination by combining different data analysis methods. The established strategy may provide a new method for improving the the validity and accuracy of Squama Manis in clinical use.

177 Saponins, Including 11 New Compounds in Wild Ginseng Tentatively Identified via HPLC-IT-TOF-MSn, and Differences among Wild Ginseng, Ginseng under Forest, and Cultivated Ginseng

Wild ginseng (W-GS), ginseng under forest (F-GS, planted in mountain forest and growing in natural environment), and cultivated ginseng (C-GS) were compared via HPLC-DAD and HPLC-IT-TOF-MSⁿ. A total of 199 saponins, including 16 potential new compounds, were tentatively identified from 100 mg W-GS (177 saponins in W-GS with 11 new compounds), F-GS (56 saponins with 1 new compound), and C-GS (60 saponins with 6 new compounds). There were 21 saponins detected from all the W-GS, F-GS, and C-GS. Fifty saponins were only detected from W-GS, including 23 saponins found in ginseng for the first time. Contents of ginsenosides Re (12.36–13.91 mg/g), Rh₁ (7.46–7.65 mg/g), Rd (12.94–12.98 mg/g), and the total contents (50.52–55.51 mg/g) of Rg₁, Re, Rf, Rb₁, Rg₂, Rh₁, and Rd in W-GS were remarkably higher than those in F-GS (Re 1.22–3.50 mg/g, Rh₁ 0.15–1.49 mg/g, Rd 0.19–1.49 mg/g, total 5.69–18.74 mg/g), and C-GS (Re 0.30–3.45 mg/g, Rh₁ 0.05–3.42 mg/g, Rd 0.17–1.68 mg/g, total 2.99–19.55 mg/g). Contents of Re and Rf were significantly higher in F-GS than those in C-GS (p < 0.05). Using the contents of Re, Rf, or Rb₁, approximately a half number of cultivated ginseng samples could be identified from ginseng under forest. Contents of Rg₁, Re, Rg₂, Rh₁, as well as the total contents of the seven ginsenosides were highest in ginseng older than 15 years, middle–high in ginseng between 10 to 15 years old, and lowest in ginseng younger than 10 years. Contents of Rg₁, Re, Rf, Rb₁, Rg₂, and the total of seven ginsenosides were significantly related to the growing ages of ginseng (p < 0.10). Similarities of chromatographic fingerprints to W-GS were significantly higher (p < 0.05) for F-GS (median: 0.824) than C-GS (median: 0.745). A characteristic peak pattern in fingerprint was also discovered for distinguishing three types of ginseng. Conclusively, wild ginseng was remarkably superior to ginseng under forest and cultivated ginseng, with ginseng under forest slightly closer to wild ginseng than cultivated ginseng. The differences among wild ginseng, ginseng under forest, and cultivated ginseng in saponin compositions and contents of ginsenosides were mainly attributed to their growing ages.

[Dynamic chromatopharmacokinetics model for components in Chinese medicine and validation in Buyang Huanwu Decoction]

The Chinese medicine is mostly derived from plants or animals, highly polymorphic, with dynamic components which are reflected by the characteristic peaks and fingerprint peaks in chromatographic fingerprints. The chromatopharmacokinetics method for determined components is not applicable due to dynamic changes of chromatopharmacokinetics. Based on the preliminary study, dynamic pharmacokinetics mathematical model for multiple components in Chinese medicine was set up and verified by Buyang Huanwu Decoction as the model drug, applying the principle of the total quantum statistical moment(TQSM), superimposing or subtracting the relevant statistical parameters in blood samples and blank samples. This provided a new method for the chromatopharmacokinetic study of Chinese medicine. HPLC was used to determine the TQSM parameters in blood and blank sample fingerprints of Buyang Huanwu Decoction at each point, and the overall TQSM parameters of drug-containing blood sample and blank samples were obtained with addition calculation of TQSM; while the initial TQSM of the pure drug can be obtained with subtraction calculation. The metabolic and absorption equilibrium constants were calculated iteratively to a steady state using the estimated metabolic equilibrium constants, then the metabolic chromatopharmacokinetic parameters in rats were obtained: VUC_T 1.262×10~8 mAu·s, MRT_T 37.48 h, VRT_T 9.016×10~2 h~2, CL_T 25.79 mL·h~(-1)·kg~(-1), Vs 1.586×10~2 mL·kg~(-1), t_(T,0.5) 6.15 h, respectively. This suggested that 95% of the compounds in whole recipe were metabolized and secreted from the body after 0-96.33 h. The experiment verified that the established mathematical model and the total quantum moment statistics parameters can represent the dose-time relationship of Buyang Huanwu Decoction, which can be used to study on in vivo metabolism dynamics for Chinese medicine.

Fatty Acids-Based Quality Index to Differentiate Worldwide Commercial Pistachio Cultivars

The fatty acid profiles of five main commercial pistachio cultivars, including Ahmad-Aghaei, Akbari, Chrok, Kalle-Ghouchi, and Ohadi, were determined by gas chromatography: palmitic (C16:0), palmitoleic (C16:1), stearic (C18:0), oleic (C18:1), linoleic (C18:2), linolenic (C18:3), arachidic (C20:0), and gondoic (C20:1) acid. Based on the oleic to linoleic acid (O/L) ratio, a quality index was determined for these five cultivars: Ohadi (2.40) < Ahmad-Aghaei (2.60) < Kale-Ghouchi (2.94) < Chrok (3.05) < Akbari (3.66). Principal component analysis (PCA) of the fatty acid data yielded three significant PCs, which together account for 80.0% of the total variance in the dataset. A linear discriminant analysis (LDA) model that was evaluated with cross-validation correctly classified almost all of the samples: the average percent accuracy for the prediction set was 98.0%. The high predictive power for the prediction set shows the ability to indicate the cultivar of an unknown sample based on its fatty acid chromatographic fingerprint.

A Novel and Practical Chromatographic "Fingerprint-ROC-SVM" Strategy Applied to Quality Analysis of Traditional Chinese Medicine Injections: Using KuDieZi Injection as a Case Study

Fingerprinting is widely and commonly used in the quality control of traditional Chinese medicine (TCM) injections. However, current studies informed that the fingerprint similarity evaluation was less sensitive and easily generated false positive results. For this reason, a novel and practical chromatographic “Fingerprint-ROC-SVM” strategy was established by using KuDieZi (KDZ) injection as a case study in the present article. Firstly, the chromatographic fingerprints of KDZ injection were obtained by UPLC and the common characteristic peaks were identified with UPLC/Q-TOF-MS under the same chromatographic conditions. Then, the receiver operating characteristic (ROC) curve was used to optimize common characteristic peaks by the AUCs value greater than 0.7. Finally, a support vector machine (SVM) model, with the accuracy of 97.06%, was established by the optimized characteristic peaks and applied to monitor the quality of KDZ injection. As a result, the established model could sensitively and accurately distinguish the qualified products (QPs) with the unqualified products (UPs), high-temperature processed samples (HTPs) and high-illumination processed samples (HIPs) of KDZ injection, and the prediction accuracy was 100.00%, 93.75% and 100.00%, respectively. Furthermore, through the comparison with other chemometrics methods, the superiority of the novel analytical strategy was more prominent. It indicated that the novel and practical chromatographic “Fingerprint-ROC-SVM” strategy could be further applied to facilitate the development of the quality analysis of TCM injections.

Optimization of Ultrasonic-assisted Extraction of Fatty Acids in Seeds of Brucea Javanica (L.) Merr. from Different Sources and Simultaneous Analysis Using High-Performance Liquid Chromatography with Charged Aerosol Detection

Our research aimed to optimize the oil extraction process and determine the fatty acids in Brucea javanica (L.) Merr. seeds. The extraction technology was optimized using response surface methodology. A Box-Behnken design was employed to investigate the effects of three independent variables on an ultrasonic-assisted extraction technique, namely, sonication time (X₁: 20–40 min), liquid–solid ratio (X₂: 16:1 mL/g–24:1 mL/g), and ethanol concentration (X₃: 90%–100%). The optimum conditions of sonication time, liquid–solid ratio, and ethanol concentration were 40 min, 24:1 mL/g, and 100%, respectively. The content of fatty acids and the oil yield were 14.64 mg/g and 16.87%, respectively, which match well with the predicted models. The optimum number of extraction times was eventually identified as two. A new rapid method for the qualitative and quantitative analysis of the fatty acids of B. javanica (L.) Merr. seed oil using HPLC with a charged aerosol detector was described. The fatty acid contents of 14 batches of B. javanica (L.) Merr. seed oil were determined, and the relevance and difference were analyzed by fingerprint analysis. The fingerprint has five common peaks, and the similarity was greater than 0.991. HPLC analysis represents a specialized and rational approach for the quality identification and comprehensive evaluation of B. javanica (L.) Merr. seed oils.

Identification of Free Radical Scavengers from Brazilian Green Propolis Using Off-Line HPLC-DPPH Assay and LC-MS

Brazilian green propolis is known as an appreciable natural antioxidant with abundant polyphenolic compounds. For quality control, a fingerprint-efficacy study of Brazilian green propolis was carried out in this work. Chemical fingerprints of Brazilian green propolis from 22 different sources were determined by HPLC and investigated by similarity analysis. The fingerprint-efficacy relationships between chemical fingerprint and DPPH radical-scavenging activity were established. The results showed that 14 characteristic common peaks were identified, and 9 compounds were discovered with free radical-scavenging activities. Caffeoylquinic acids and artepillin C might be the major effective components for quality control of Brazilian green propolis due to their specificity and strong antioxidant activity. This study provides new markers for the quality assessment of Brazilian green propolis and its derived products.

Development of Chromatographic Fingerprints of Eurycoma longifolia (Tongkat Ali) Roots Using Online Solid Phase Extraction-Liquid Chromatography (SPE-LC)

E. longifolia is attracting interest due to its pharmacological properties and pro-vitality effects. In this study, an online SPE-LC approach using polystyrene divinyl benzene (PSDVB) and C18 columns was developed in obtaining chromatographic fingerprints of E. longifolia. E. longifolia root samples were extracted using pressurized liquid extraction (PLE) technique prior to online SPE-LC. The effects of mobile phase compositions and column switching time on the chromatographic fingerprint were optimized. Validation of the developed method was studied based on eurycomanone. Linearity was in the range of 5 to 50 µg∙mL(-1) (r² = 0.997) with 3.2% relative standard deviation of peak area. The developed method was used to analyze 14 E. longifolia root samples and 10 products (capsules). Selected chemometric techniques: cluster analysis (CA), discriminant analysis (DA), and principal component analysis (PCA) were applied to the fingerprint datasets of 37 selected peaks to evaluate the ability of the chromatographic fingerprint in classifying quality of E. longifolia. Three groups were obtained using CA. DA yielded 100% correlation coefficient with 19 discriminant compounds. Using PCA, E. longifolia root samples were clearly discriminated from the products. This study showed that the developed online SPE-LC method was able to provide comprehensive evaluation of E. longifolia samples for quality control purposes.

Quality Evaluation of Traditional Chinese Medicine Compounds in Xiaoyan Lidan Tablets: Fingerprint and Quantitative Analysis Using UPLC-MS

XiaoyanLidan tablets (XYLDTs) are traditional Chinese medicines frequently used for syndromes of the liver and gallbladder, cholecystitis and cholangitis. To evaluate the consistency of the quality of commercial XYLDT preparations, we established a simple and reliable ultra-performance liquid chromatography (UPLC) method with a photodiode array (PDA) detector and mass spectrometry (MS), including a fingerprint analysis and quantification of the main pharmacologically-active markers. In the UPLC-PDA detection-based fingerprint analysis of XYLDTs, approximately 39 peaks were found in the XYLDT chromatogram, 26 of which were attributed to Picrasmaquassioides, nine to Andrographis and four to Isodonserra. Subsequently, the structures of these bioactive markers were identified through ESI-MS analyses. Using the chemometricmethods of similarity analysis and principal component analysis, the five significant herbal componentswere determined as 4-methoxy-5-hydroxycanthin-6-one, andrographolide, dehydroandrographolide, neoandrographolide and rosmarinic acid, and these components were qualitatively assessed. Our experimental results demonstrated that combining the fingerprint analysis with UPLC-MS and multi-ingredient determination is useful for rapid pharmaceutical quality evaluation. Moreover, the combined approach can potentially differentiate the origin, determine the authenticity and assess the overall quality of the formulae.

An Approach Based on HPLC-Fingerprint and Chemometrics to Quality Consistency Evaluation of Matricaria chamomilla L. Commercial Samples

Chamomile has been used as an herbal medication since ancient times and is still popular because it contains various bioactive phytochemicals that could provide therapeutic effects. In this study, a simple and reliable HPLC method was developed to evaluate the quality consistency of nineteen chamomile samples through establishing a chromatographic fingerprint, quantification of phenolic compounds and determination of antioxidant activity. For fingerprint analysis, 12 peaks were selected as the common peaks to evaluate the similarities of commercial samples of chamomile obtained from different manufacturers. A similarity analysis was performed to assess the similarity/dissimilarity of chamomile samples where values varied from 0.868 to 0.990 what indicating that samples from different manufacturers were consistent. Additionally, simultaneous quantification of five phenolic acids (gallic, caffeic, syringic, p-coumaric, ferulic) and four flavonoids (rutin, myricetin, quercetin and keampferol) was performed to interpret the quality consistency. In quantitative analysis, the nine individual phenolic compounds showed good regression (r > 0.9975). Inter- and intra-day precisions for all analyzed compounds expressed as relative standard deviation (CV) ranged from 0.05% to 3.12%. Since flavonoids and other polyphenols are commonly recognized as natural antioxidants, the antioxidant activity of chamomile samples was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing/antioxidant power (FRAP) assay. Correlation analysis was used to assess the relationship between antioxidant activity and phenolic composition, and multivariate analysis (PCA and HCA) were applied to distinguish chamomile samples. Results shown in the study indicate high similarity of chamomile samples among them, widely spread in the market and commonly used by people as infusions or teas, as well as that there were no statistically significant differences among them, which in turn is a proof of high quality of commercially available samples of chamomile. The study indicated that the combination of chromatographic fingerprint and quantitative analysis can be readily utilized as a quality consistency method for chamomile and related medicinal preparations. Moreover, the applied strategy seems to be the most promising for the assessment of the investigated plant material.

Cluster analysis of commercial samples of Bauhinia spp. using HPLC-UV/PDA and MCR-ALS/PCA without peak alignment procedure

INTRODUCTION

Bauhinia forficata Link. is recognised by the Brazilian Health Ministry as a treatment of hypoglycemia and diabetes. Analytical methods are useful to assess the plant identity due the similarities found in plants from Bauhinia spp. HPLC-UV/PDA in combination with chemometric tools is an alternative widely used and suitable for authentication of plant material, however, the shifts of retention times for similar compounds in different samples is a problem.

OBJECTIVE

To perform comparisons between the authentic medicinal plant (Bauhinia forficata Link.) and samples commercially available in drugstores claiming to be "Bauhinia spp. to treat diabetes" and to evaluate the performance of multivariate curve resolution - alternating least squares (MCR-ALS) associated to principal component analysis (PCA) when compared to pure PCA.

METHODOLOGY

HPLC-UV/PDA data obtained from extracts of leaves were evaluated employing a combination of MCR-ALS and PCA, which allowed the use of the full chromatographic and spectrometric information without the need of peak alignment procedures.

RESULTS

The use of MCR-ALS/PCA showed better results than the conventional PCA using only one wavelength. Only two of nine commercial samples presented characteristics similar to the authentic Bauhinia forficata spp., considering the full HPLC-UV/PDA data.

CONCLUSION

The combination of MCR-ALS and PCA is very useful when applied to a group of samples where a general alignment procedure could not be applied due to the different chromatographic profiles. This work also demonstrates the need of more strict control from the health authorities regarding herbal products available on the market.