Mohamed M. Al-Azizi

Application of Chemometrics in Authentication of Herbal Medicines: A Review

INTRODUCTION Herbal medicines (HM) and their preparations have been widely used for hundreds of years all over the world. However, they have not been officially recognised due to a lack of adequate or accepted research methodology for their evaluation. OBJECTIVE To present a concise overview of the recent applications of chemometrics in solving the ambiguity of herbal medicine authentication during the last two decades. METHODOLOGY Studies involving the applications of chemometric analysis in combination with different analytical methods were classified according to the method of analysis used including chromatographic (HPLC, GC and CE), spectroscopic (NMR, IR, UV and ICP) and genetic analysis (RAPD). The purpose of each of these studies was classified into one of three main categories: taxonomic discrimination, quality assessment or classification between plants of different geographic origins. RESULTS This review comprises over 150 studies, covering the past two decades, emphasising the significance of chemometric methods in the discrimination of many herbs from closely related species and from adulterants, based on the principal bioactive components and phytochemical diversity. Furthermore, the differentiation between varieties and hybrids was achieved in addition to the prediction of the active components by quantitative methods of analysis. Discrimination according to geographical origin and localities, processing methods, DNA profiling and metabolomics were also efficiently investigated. CONCLUSION Chemometric methods have provided an efficient and powerful tool for the quality control and authentication of different herbs.

A modern approach to the authentication and quality assessment of thyme using UV spectroscopy and chemometric analysis.

INTRODUCTION Recently, the fields of chemometrics and multivariate analysis have been widely implemented in the quality control of herbal drugs to produce precise results, which is crucial in the field of medicine. Thyme represents an essential medicinal herb that is constantly adulterated due to its resemblance to many other plants with similar organoleptic properties. OBJECTIVE To establish a simple model for the quality assessment of Thymus species using UV spectroscopy together with known chemometric techniques. The success of this model may also serve as a technique for the quality control of other herbal drugs. MATERIALS AND METHODS The model was constructed using 30 samples of authenticated Thymus vulgaris and challenged with 20 samples of different botanical origins. The methanolic extracts of all samples were assessed using UV spectroscopy together with chemometric techniques: principal component analysis (PCA), soft independent modeling of class analogy (SIMCA) and hierarchical cluster analysis (HCA). RESULTS The model was able to discriminate T. vulgaris from other Thymus, Satureja, Origanum, Plectranthus and Eriocephalus species, all traded in the Egyptian market as different types of thyme. The model was also able to classify closely related species in clusters using PCA and HCA. The model was finally used to classify 12 commercial thyme varieties into clusters of species incorporated in the model as thyme or non-thyme. CONCLUSION The model constructed is highly recommended as a simple and efficient method for distinguishing T. vulgaris from other related species as well as the classification of marketed herbs as thyme or non-thyme.

Authentication of Monofloral Yemeni Sidr Honey Using Ultraviolet Spectroscopy and Chemometric Analysis

This work describes a simple model developed for the authentication of monofloral Yemeni Sidr honey using UV spectroscopy together with chemometric techniques of hierarchical cluster analysis (HCA), principal component analysis (PCA), and soft independent modeling of class analogy (SIMCA). The model was constructed using 13 genuine Sidr honey samples and challenged with 25 honey samples of different botanical origins. HCA and PCA were successfully able to present a preliminary clustering pattern to segregate the genuine Sidr samples from the lower priced local polyfloral and non-Sidr samples. The SIMCA model presented a clear demarcation of the samples and was used to identify genuine Sidr honey samples as well as detect admixture with lower priced polyfloral honey by detection limits >10%. The constructed model presents a simple and efficient method of analysis and may serve as a basis for the authentication of other honey types worldwide.

Iridal glycosides from Iris spuria (Zeal), cultivated in Egypt.

Fractionation of a methanol extract obtained from rhizomes of I. spuria (Zeal) resulted in the isolation of seven iridalglycosides 5a,b, 6a-c, 7, 8. The structures of the aglycons and the position of the glycosidic bonds were elucidated by spectroscopic analyses. The nature of the sugar moieties was determined as glucose from capillary GC and GC/MS analyses after hydrolysis of the compounds, reduction and derivatization of the resulting hexitols in comparison to authentic standards. Methylation analysis revealed the glycosyl-linkage composition. The number and position of the glucose residues was determined by ozonolysis.

Chemical Composition of Essential Oil from Doum Fruits Hyphaene thebaica (Palmae)

Abstract Results of GC and GC-MS analysis of essential oil isolated from doum fruits (Hyphaene thebaica) revealed the presence of fifty-seven compounds. Fifty of them could be identified with monoterpenes represent 15.97 % including compounds such as sabinene (0.82 %), β-pinene (1.98 %), limonene (2.42 %), terpinen 4-ol (1.77 %) %), α-terpineol (0.95 %). While diterpenes represent 40.49 %, of which incensole (17.52 %) and incensole acetate (19.81 %) were found to be the main components. Oxygenated compounds constituted 66.78 % of the total compounds identified which indicated the economical value of this oil. The scent of doum oil fruits may be attributed to the presence of volatile diterpenes as cembrene A, cembrene C, incensole and incensole acetate; these compounds are reported here for the first time in family Palmae.

Studying the possible biotransformation of the cytotoxic diterpenoid paclitaxel using Jatropha curcas cell suspension culture.

Aims: To establish a cell suspension culture of Jatropha curcas, family Euphorbiaceae for the biotransformation of the diterpenoid anti-cancer compound paclitaxel. Study Design: The development and maintenance of callus lines from the leaves and petioles of J. curcas and the study of the culture growth curve followed by the inoculation of the callus with paclitaxel as the substrate and monitoring of the culture viability as well as substrate biotransformation. Methodology: Explants from the leaves and petioles of J. curcas were prepared and placed on MS supplemented media for callus induction and maintained by regular subculturing until a stable callus line was achieved. Some of the callus tissue was transferred to MS liquid medium to produce cell suspension cultures. Three sets of cell suspension cultures were established for 5, 10 and 14 days respectively under the same conditions. Paclitaxel (5 mg) was administrated to each flask and incubated for 3, 6 and 10 days. Results: A callus line of J. curcas leaves and petioles was maintained successfully over a Research Article European Journal of Medicinal Plants, 3(2): 241-253, 2013 242 period of two consecutive years without any change in growth rate. A stable cell suspension culture was developed using the obtained callus and maximum increase in fresh weight was reached on day 21 which was 5-6 fold over initial fresh weight. The cell suspension cultures were inoculated with the diterpenoid paclitaxel (5 mg) at different time intervals through the growth cycle phases. The incubation of paclitaxel proved that the cell culture biotransformation capability could not affect the paclitaxel molecular structure and that the applied dose of paclitaxel was not cytotoxic to the cell cultures up to 18 days of incubation. Conclusion: This is the first report of a biotransformation trial using J. curcas cell culture and results obtained should be considered when using J. curcas cell line for terpenoid biotransformation.