Determination of the active principles of Catha Edulis: Quali–quantitative analysis of cathinone, cathine, and phenylpropanolamine

Plant Poisons in the Garden: A Human Risk Assessment

A study of the plants, and their associated poisons, in the Poison Garden at The Alnwick Garden was undertaken across a calendar year. By selecting 25 plants in the Poison Garden, we have been able to develop a single chromatographic method for the determination and quantification of 15 plant toxins by liquid chromatography mass spectrometry (LC-MS). Chromatographic separation was achieved on a C18 column (3.5 µm, 100 × 4.6 mm) with a gradient method using water +0.1% formic acid and methanol +0.1% formic acid. The developed method was validated for precision, linearity, limits of detection and quantification and extraction recoveries. The method showed good linearity with a R2 value of >0.995 for all 15 compounds with good precision of 10.7%, 6.7% and 0.3% for the low, medium and high calibration points, respectively. The LC-MS method was used to analyse 25 plant species, as well as their respective parts (i.e., bulb, flower, fruit, leaf, pollen, seed, stem and root), to assess the human risk assessment to children (aged 1 to <2 years) in relation to the plant toxin and its respective LD50. The analysis found that the greatest potential health risks were due to the ingestion of Colchicum autumnale and Atropa belladonna. As a caution, all identified plants should be handled with care with additional precautionary steps to ensure nil contact by children because of the potential likelihood of hand-to-mouth ingestion.

Khat Chewing and Lipid Profile in Human and Experimental Animals

BACKGROUND

Catha edulis, also known as khat or qat, is a plant that grows in East Africa and southern Arabia. Several millions of people chew the leaves and twigs of khat plant for their central stimulating amphetamine-like effects. Khat chewing is becoming more common in Europe and the United States, owing to worldwide migration.

OBJECTIVE

This review examines the khat ingredients, global prevalence, and legal status as well as its effects on lipid profile. Methodology. A literature search was performed using PubMed, Scopus, and Google Scholar to collect information within articles published up to April 2021 with the goal of identifying relevant studies. The proposed mechanisms of cathinone effects on total cholesterol and triglyceride were also discussed.

CONCLUSION

The khat chewing habit is considered as a serious economic and health issue that needs specialized programs to assist those people to quit or reducing this habit.

Determination of cathinone and cathine in Khat plant material by LC-MS/MS: Fresh vs. dried leaves

The consumption of Khat leaves represents an ancient kind of drug abuse mainly observed in Eastern Africa and the Arab Peninsula among adult men. For this purpose, the leaves are directly collected from the shrub "Catha edulis" prior to extensive chewing process. Seizures in Europe are rare, since the leaves have to undergo quick transportation: After a short period of time, the harvested leaves decompose and suffer in decrease of concentration of the active ingredient cathinone, which makes long term transportation difficult. As an alternative, plant material can be dried to increase life period. In the past years, an increasing number of seizures were made by Austrian police, however, the content of cathinone and cathine in dry material is widely unknown. In this work, a seizure of fresh Khat leaves was compared with two seizures of dried material in terms of concentration of cathinone and cathine using LC-MS/MS analysis. For fresh leaves, a purity grade was found to be 0.115-0.158% for cathinone and 0.172-0.192% for cathine, respectively. In contrast, subsequent storage of dried Khat leaves over months led to a dramatic loss of cathinone: Analysis of two seizures revealed that concentration of cathinone dropped to 0.021-0.023%. These findings are intended to serve as a guideline for Justice authorities to estimate the content of the controlled ingredients of Khat leaves in future.

Screening of new psychoactive substances (NPS) by gas-chromatography/time of flight mass spectrometry (GC/MS-TOF) and application to 63 cases of judicial seizure

A screening method for the separation and identification of more than fifty NPS is proposed. The method is based on fast gas-chromatography/time of flight mass spectrometry (FAST-GC/MS-TOF). Thanks to the shorter and narrower capillary column and to the rapid acquisition of the TOF detector a huge number of compounds are separated in a very short time of analysis (10 min). Only a few peaks were overlapped. The possibility to apply deconvolution by the software of the GC/MS-TOF instrument allowed the unequivocal identification also for the superimposed peaks. Linearity and LOD was studied and the method was applied to 63 cases of powders seized by the judicial authority at the airport of Milano Malpensa in Northern Italy in the period 2014–2017.

Preparative HPLC for large scale isolation, and salting-out assisted liquid-liquid extraction based method for HPLC-DAD determination of khat (Catha edulis Forsk) alkaloids

Background

Khat (Catha edulis Forsk) is an evergreen shrub of the Celastraceae family. It is widely cultivated in Yemen and East Africa, where its fresh leaves are habitually chewed for their momentary pleasures and stimulation as amphetamine-like effects. The main psychostimulant constituents of khat are the phenylpropylamino alkaloids: cathinone, cathine and norephedrine.

Results

In this study, simple procedures based on preparative HPLC and salting-out assisted liquid–liquid extraction (SALLE) based methods were developed respectively for large scale isolation and the extraction of psychoactive phenylpropylamino alkaloids; cathinone, cathine and norephedrine, from khat (Catha edulis Forsk) chewing leaves, a stimulant and drug of abuse plant. The three khat alkaloids were directly isolated from the crude oxalate salt by preparative HPLC–DAD method with purity > 98%. In addition, a modified (SALLE) method has been developed and evaluated for the extraction efficiency of psychoactive phenylpropylamino alkaloids from khat (Catha edulis Forsk) chewing leaves. An in situ two steps extraction protocol was followed without dispersive SPE clean up. The method involves extraction of the samples with 1% HAc and QuEChERS salt (1.0 g of CH₃COONa and 6.0 g of MgSO₄) followed by subsequent in situ liquid–liquid partitioning by adding ethyl acetate and NaOH solution. The optimized method allowed recoveries of 80–86% for the three alkaloids from khat sample with relative standard deviation (RSD) values less than 15% and limits of detection (0.85–1.9 μg/mL).

Conclusion

The method was found to be simple, cost-effective and provides cleaner chromatogram with good selectivity and reproducibility. The SALLE based protocol provided as good results as the conventional extraction method (ultrasonic assisted extraction followed by solid phase extraction, UAE–SPE) and hence the method can be applicable in forensic and biomedical sectors.

Electronic supplementary material

The online version of this article (doi:10.1186/s13065-017-0337-6) contains supplementary material, which is available to authorized users.

Conflicting reports on the role of the glycemic effect of Catha edulis (Khat): A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally, the leaves of Catha edulis Forsskal (Khat) are consumed by the people of Yemen primarily for its recreational effect, and secondarily, for achieving certain tasks. Additionally, Yemeni diabetics chew such leaves in the belief that this can control their elevated blood glucose level.

AIMS

This review focuses on outlining the findings of studies that have been conducted to display the glycemic effect of Catha edulis, while trying to balance it with findings of the association of its chewing with the development of type 2 diabetes mellitus (DM).

MATERIALS AND METHODS

The search strategy adopted was based on a comprehensive research in Medline, PubMed, Web of Science, JSTOR, Scopus and Cochrane for articles, proceeding abstracts and theses to identify complete reports written in the English language about the glycemic effect of Catha edulis in humans and animals from 1976 to 2016. In addition, bibliographies were also reviewed to find additional reports not otherwise published. Thirty seven records were identified of which, 25 eligible studies were included in the meta-analysis using blood glucose as an outcome measurement. Studies were divided into four subgroups according to the experimental model, namely; non-diabetic animals, diabetic animals, non-diabetic humans and diabetic humans. The pooled mean difference (MD) of blood glucose between experimental and control were calculated using random effects model of the weighted mean difference of blood glucose with 95% confidence interval (CI). Heterogeneity between studies was tested using I(2) statistic and a value of P<0.05 was considered to indicate statistical significance.

RESULTS

The scientific reports in the literature prevailed that the glycemic effect of Catha edulis were greatly conflicting with the majority of studies indicating that Catha edulis has a mild hypoglycemic effect. However, the meta-analysis indicted that the overall result showed an insignificant reduction in blood glucose (MD=-9.70, 95% CI: -22.17 to 2.76, P=0.13, with high heterogeneity between subgroups, I(2)=88.2%, P<0.0001). In addition, pooled mean difference of blood glucose of non-diabetic animals, diabetic animals and non-diabetic humans showed an insignificant reduction in blood glucose (MD=-18.55, 95% CI: -39.55 to 2.50, P<0.08, MD=-52.13%, 95% CI: -108.24 to 3.99, P=0.07 and MD=-2.71%, 95% CI: -19.19 to -13.77, P=0.75) respectively. Conversely, a significant elevation in the pooled mean difference of blood glucose in diabetic humans was indicated (MD=67.18, 95% CI: 36.93-97.43, P<0.0001). The conflict shown in the glycemic effect of Catha edulis is thought to be cultivar-related, while demographic and epidemiological reports suggested that chewing Catha edulis might be a predisposing factor contributing to the development of type 2 DM.

CONCLUSION

It was difficult to draw a meaningful conclusion from both the systematic and the meta-analysis with respect to the glycemic effect of Catha edulis since the meta-analysis results were insignificant with high heterogeneity among subgroups and are greatly conflicting. The variation is most likely due to unadjusted experimental factors or is related to Catha edulis itself, such as the differences in the phytochemical composition. Therefore, it is highly recommended that further studies of the glycemic effect of the cultivar of Catha edulis being studied should come with the identification and quantification of phytochemical content so that a meaningful assessment can be made with regard to its hypoglycemic properties. In addition, well-controlled clinical studies should be conducted to confirm whether or not chewing Catha edulis is associated with the development of type 2 DM, since this would be a source of concern seeing that the plant is widely consumed in certain populations.

Capillary electrophoretic and extraction conditions for the analysis of Catha edulis FORKS active principles

A capillary electrophoretic method, which allowed the detection and separation of the active principles of Catha edulis, i.e. cathinone, cathine and phenylpropanolamine, was developed. A suitable internal standard (nicotinamide), which permitted the quantification of the analytes reducing the variability of the migration times due to EOF changes, was identified. The analytical method was validated, assessing linearity, sensitivity and repeatability, showing optimal features for the analysis of the vegetable material. Moreover extraction conditions were investigated to achieve the exhaustion of the plant material in the fastest and most efficient way to meet the requirements of the Court.