The Eleutherococcus senticosus fruits' intractum affects changes in the transepithelial electric potential in the distal section of the rabbit's large intestine and inhibits hyaluronidase.

ETHNOPHARMACOLOGICAL RELEVANCE: Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. has been used in traditional Russian medicine due to its recognized immunostimulant and anti-inflammatory activities. Compounds present in the fruits have demonstrated the capability to modulate the activity of enzymes such as hyaluronidase, suggesting their potential value in the development of effective therapies for various conditions where anti-inflammatory properties are beneficial, such as gastrointestinal diseases and tumor growth. AIM OF THE STUDY: In order to support the use of the fruits in folk medicine, this study is aimed to evaluate, post-mortem, the impact of E. senticosus fruits intractum (40 % extract made from fresh fruits) on the transepithelial electrogenic transport of sodium ions in the colon. The objective of this study was also to examine the impact of the intractum on proinflammatory serum hyaluronidase in children diagnosed with acute leukemia. METHODS: The study employed the Ussing technique to examine electrophysiological characteristics of isolated epithelial tissue, using the distal colon wall isolated from 10 New Zealand white male rabbits. The effect of the intractum on the inhibition of human serum hyaluronidase was examined with turbidimetric screening methods, using the blood samples collected from patients diagnosed with acute leukemia. RESULTS: For the first time, we discovered that the intractum used in the stimulation fluid, caused hyperpolarization reactions in colon tissue. Statistical analysis showed that these reactions were significantly different in relation to the control. The intractum significantly inhibited hyaluronidase activity with the mean value by group of 60 %, and 40 % for aescin used as a control. CONCLUSION: The results support the traditional use of the fruits in inflammatory-related diseases. The use of intractum of E. senticosus on the distal colon wall demonstrates its protective effect on the wall integrity and in a relation to hyaluronidase inhibition may additionally indicate its anti-inflammatory property. Thus, the results mean that the intractum may be used in colon-related diseases.

Saudi Arabian Plants: A Powerful Weapon against a Plethora of Diseases.

The kingdom of Saudi Arabia (SA) ranks fifth in Asia in terms of area. It features broad biodiversity, including interesting flora, and was the historical origin of Islam. It is endowed with a large variety of plants, including many herbs, shrubs, and trees. Many of these plants have a long history of use in traditional medicine. The aim of this review is to evaluate the present knowledge on the plants growing in SA regarding their pharmacological and biological activities and the identification of their bioactive compounds to determine which plants could be of interest for further studies. A systematic summary of the plants' history, distribution, various pharmacological activities, bioactive compounds, and clinical trials are presented in this paper to facilitate future exploration of their therapeutic potential. The literature was obtained from several scientific search engines, including Sci-Finder, PubMed, Web of Science, Google Scholar, Scopus, MDPI, Wiley publications, and Springer Link. Plant names and their synonyms were validated by 'The Plant List' on 1 October 2021. SA is home to approximately 2247 plant species, including native and introduced plants that belong to 142 families and 837 genera. It shares the flora of three continents, with many unique features due to its extreme climate and geographical and geological conditions. As plants remain the leading supplier of new therapeutic agents to treat various ailments, Saudi Arabian plants may play a significant role in the fight against cancer, inflammation, and antibiotic-resistant bacteria. To date, 102 active compounds have been identified in plants from different sites in SA. Plants from the western and southwestern regions have been evaluated for various biological activities, including antioxidant, anti-cancer, antimicrobial, antimalarial, anti-inflammatory, anti-glycation, and cytotoxic activities. The aerial parts of the plants, especially the leaves, have yielded most of the bioactive compounds. Most bioactivity tests involve in vitro assessments for the inhibition of the growth of tumour cell lines, and several compounds with in vitro antitumour activity have been reported. More in-depth studies to evaluate the mode of action of the compounds are necessary to pave the way for clinical trials. Ecological and taxonomical studies are needed to evaluate the flora of SA, and a plan for the conservation of wild plants should be implemented, including the management of the protection of endemic plants.

Effectiveness of Volatile Natural Deep Eutectic Solvents (VNADESs) for the Green Extraction of Chelidonium majus Isoquinoline Alkaloids.

The Chelidonium majus plant is rich in biologically active isoquinoline alkaloids. These alkaline polar compounds are isolated from raw materials with the use of acidified water or methanol; next, after alkalisation of the extract, they are extracted using chloroform or dichloromethane. This procedure requires the use of toxic solvents. The present study assessed the possibility of using volatile natural deep eutectic solvents (VNADESs) for the efficient and environmentally friendly extraction of Chelidonium alkaloids. The roots and herb of the plant were subjected three times to extraction with various menthol, thymol, and camphor mixtures and with water and methanol (acidified and nonacidified). It has been shown that alkaloids can be efficiently isolated using menthol-camphor and menthol-thymol mixtures. In comparison with the extraction with acidified methanol, the use of appropriate VNADESs formulations yielded higher amounts of protopine (by 16%), chelidonine (35%), berberine (76%), chelerythrine (12%), and coptisine (180%). Sanguinarine extraction efficiency was at the same level. Additionally, the values of the contact angles of the raw materials treated with the tested solvents were assessed, and higher wetting dynamics were observed in the case of VNADESs when compared with water. These results suggest that VNADESs can be used for the efficient and environmentally friendly extraction of Chelidonium alkaloids.

Exploring natural products-based cancer therapeutics derived from egyptian flora.

ETHNOPHARMACOLOGICAL RELEVANCE: Egyptian plants are a rich source of natural molecules, representing considerable biodiversity due to climate variations between the Northern, Southern, Eastern and Western regions of the country. Sinai is considered a precious nature reserves preserving flora, fauna, marine organisms, and historical habitats with ancient origins. Here, traditional medicinal approaches have been used for hundreds of years. Healthy lifestyles, low levels of stress and microbial infections, and a dependence on flora and herbal medicine might in combination explain why the burden of cancer is lower in some regions than in others. AIM OF THE STUDY: The primary aim of this review is to document the plants and natural products that are used as foods and medicines in Egypt, in general, and in Sinai, in particular, with a focus on those with demonstrated anticancer activities. The documented traditional uses of these plants are described, together with their chemical and pharmacological activities and the reported outcomes of clinical trials against cancer. MATERIALS AND METHODS: A literature search was performed to identify texts describing the medicinal plants that are cultivated and grown in Egypt, including information found in textbooks, published articles, the plant list website (http://www.theplantlist.org/), the medicinal plant names services website (http://mpns.kew.org/mpns-portal/), and web databases (PubMed, Science Direct, and Google Scholar). RESULTS AND DISCUSSION: We collected data for most of the plants cultivated or grown in Egypt that have been previously investigated for anticancer effects and reported their identified bioactive elements. Several plant species, belonging to different families and associated with 67 bioactive compounds, were investigated as potential anticancer agents (in vitro studies). The most potent cytotoxic activities were identified for the families Asteraceae, Lamiaceae, Chenopodiaceae, Apocynaceae, Asclepiadaceae, Euphorbiaceae, Gramineae, and Liliaceae. The anticancer activities of some species, such as Punica granatum L., Nerium oleander L., Olea europea L., Matricaria chamomilla L., Cassia acutifolia L., Nigella sativa L., Capsicum frutescens L., Withania somnifera L., and Zingiber officinale Roscoe, have been examined in clinical trials. Among the various Egyptian plant habitats, we found that most of these plants are grown in the North Sinai, New-Delta, and Giza Governorates. CONCLUSION: In this review, we highlight the role played by Egyptian flora in current medicinal therapies and the possibility that these plants may be examined in further studies for the development of anticancer drugs. These bioactive plant extracts form the basis for the isolation of phytochemicals with demonstrated anticancer activities. Some active components derived from these plants have been applied to preclinical and clinical settings, including resveratrol, quercetin, isoquercetin, and rutin.

Antimutagenic, antigenotoxic and antiproliferative activities of Fraxinus angustifolia Vahl. leaves and stem bark extracts and their phytochemical composition.

In recent years, chronic degenerative diseases such as certain types of cancers, are becoming an evident issue. DNA damage has been for long recognized as a causal factor for cancer development because mutations or chromosomal aberrations affect oncogenes and tumor suppressor genes leading cells to malignant transformation and to the subsequent cancerous growth. Medicinal plants are often used for the prevention or treatment of various diseases with great scientific interest. Among the medicinal plants distributed in the Mediterranean region, Fraxinus angustifolia Vahl. has been used in traditional medicine for its remarkable curative properties. However, in spite of this popularity, little works have been performed on the activity so that further studies should be performed to investigate in depth the antimutagenic, antigenotoxic and antiproliferative activities of the plant. Thus, the present study was aimed to the evaluation of the potential antimutagenic, antigenotoxic and antiproliferative properties of leaves and stem bark extracts of this well-known tree. Antimutagenic activity was evaluated by Salmonella mutagenicity assay in Salmonella typhimurium TA98 and TA100 strains. The antigenotoxic potential was assessed by umu test in the strain of S. typhimurium TA1535/pSK1002. Antiproliferative activity was studied on human hepatoblastoma (HepG-2) and on breast adenocarcinoma (MCF-7) cell lines by MTT assay. Furthermore, the antiproliferative activity observed on cancer cells was compared with that on the human normal-like fibroblasts (TelCOFS02MA) and the selectivity index was calculated to understand if extracts were able to exert selective toxicity towards cancer cells. Moreover, phenolic compounds are plant substances with a large spectrum of biochemical activities with antioxidant, antimutagenic and anticarcinogenic effects. Based on the strong evidence of biological activities of phenolic compounds, the study was focused on the determination of total phenolics and flavonoids contents, and the phytochemical composition of the extracts assessed by LC/MS. The ethanol extracts of both leaves and stem barks showed significant from moderate to strong antimutagenic and antigenotoxic effects. In addition, selective cytotoxicity towards cancer cells was shown by ethanolic leaves extract and aqueous/chloroform leaves and stem bark extracts. The latter showed high levels of total phenolic contents among all the other extracts. Identified phenylethanoids (calceolariosides, verbascoside) and secoiridoids (oleuropein and ligstroside) could be responsible for the demonstrated broad spectrum of healthy properties.

Quality Markers for Astragali Radix and Its Products Based on Process Analysis.

Due to the complex nature of traditional medicines, quality control methods need to cover two aspects: compliance of raw materials with quality standards and process control. Astragali radix (AR), the roots of Astragalus mongholicus Bunge, was selected in this study as an example of a widely used traditional medicine in various formulations. Astragaloside IV (AG IV) and calycosin 7-O-ß-D-glucoside (CG) are used as the markers for the quality control of AR and its products in the Chinese Pharmacopoeia. However, in the raw materials, malic acid esters of the CG and acetate esters of the astragaloside are easily decomposed into CG and AG IV during storage and processing of AR to make extracts for various preparations. The thermal stability of the isoflavonoids and astragalosides in decoction was studied. The level of CG and astragalosides (AG I/AG II/AG IV) was strongly affected by prolonged heat during processing, while calycosin was stable in the conditions. Also the major astragalosides in AR could fully converted into AG IV which eventually reaches a stable level under certain conditions. With calycosin and AG IV as marker components, practical, reproducible, and precise methods were established and applied to the quality analysis of AR from its raw materials to its intermediates and products. This study demonstrates that a full chemical profiles analysis of the whole manufacturing process (from "raw materials-intermediates/extracts-final product") is important to identify quality markers (Q-markers) and even to establish proper analysis methods for traditional Chinese medicine products.

Plants mentioned in the Islamic Scriptures (Holy Qur'ân and Ahadith): Traditional uses and medicinal importance in contemporary times.

ETHNOPHARMACOLOGICAL RELEVANCE: Over the past thousand years, Islamic physicians have collected cultural, philosophical, sociological and historical backgrounds for understanding diseases and medications. The Prophet Mohammed (Peace Be Upon Him (PBUH) said: "There is no disease that Allah has created, except that Allah also has created its cure." Therefore, Islamic scholars are encouraged to explore and use both traditional and modern forms of medicine. AIM OF THE STUDY: (1) To identify some of the medicinal plants mentioned in the Holy Qur'ân and Ahadith textbooks of the period 700-1500 AD; (2) to compare them with presently used traditional medicines; (3) to evaluate their value based on modern research; and (4) to investigate the contributions of Islamic scholars to the development of the scientific branches, particularly medicine. MATERIALS AND METHODS: A literature search was performed relating to 12 medicinal plants mentioned in the Holy Qur'ân and Ahadith using textbooks, Al-Azhar scholars, published articles, the plant list website (http://www.theplantlist.org/), the medicinal plant names services website (http://mpns.kew.org/mpns-portal/) and web databases (PubMed, Science Direct, and Google Scholar). RESULTS AND DISCUSSION: The Islamic Golden Age was a step towards modern medicine, with unique insights and multi-disciplinary aspects. Traditional Islamic Medicine has had a significant impact on the development of various medical, scientific and educational activities. Innumerable Muslim and non-Muslim physicians have built on the strong foundation of Traditional Islamic Medicine by translating the described natural remedies and effects. The influences of different ancient cultures on the traditional uses of natural products were also documented in Islamic Scriptures in the last part of the second millennium. The divine teachings of Islam combine natural and practical healing and incorporate inherited science and technology. CONCLUSION: In this review, we discuss Traditional Islamic Medicine with reference to both medical recommendations mentioned in the Holy Qur'ân and Prophetic Traditional Medicine (al-Tibb al-Nabawi). Although the molecular mechanisms and functions of some of the listed medicinal plants and their derivatives have been intensively studied, some traditional remedies have yet to be translated into clinical applications.

Historical and traditional medical applications of Carlina acaulis L. - A critical ethnopharmacological review.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Carlina (Asteraceae) comprises approx. 30 plant species growing in Europe and Asia. Carlina acaulis L. was widely used as medicine, especially in Germany and Poland. The plant root was applied e.g. to treat various skin diseases and as a diaphoretic, diuretic, and anthelmintic agent. At the end of the 19th century, the medicinal use of the plant ceased though C. acaulis roots are still used in folk medicine, especially in rural areas of the Balkans where the plant grows in the wild. AIM OF THE REVIEW: The aim of this review is to compile historical and current ethnomedical uses of C. acaulis and compare these applications with the results of modern chemical and pharmacological research of this plant. This analysis may give a lead for further research on this old, almost forgotten medicinal plant. METHODOLOGY: Historical data on the medicinal application of C. acaulis over many centuries were collected. The historical uses were compared with the contemporary indications. The present day knowledge on the chemistry and biological activity of C. acaulis is also reviewed. This information is compared with the ethnopharmacological information. RESULTS: Plants from the genus Carlina were already described by Theophrastus of Eresus, Dioscorides, Pliny the Elder, and Galen of Pergamum. Carlinae radix was still featured in Renaissance botanical books and in official pharmacopoeias, but disappeared from the scene in the 19th century. The present day information on the phytochemistry and pharmacological activity of these plants is limited. There are some data on the occurrence of common plant ingredients such as essential oil, flavonoids, phenolic acids, triterpenes, inulin, and fatty acids. However, most concern the green parts of the plant. Its medicinal use remains poorly understood, as there are only very limited results of in-vitro studies on the roots. CONCLUSIONS: The historical uses of the plant can still be found in rural areas. Yet, detailed phytochemical and pharmacological research is needed to evaluate the effectiveness and safety of the medical use of Carlina acaulis.

The Ethnopharmacologic Contribution to Bioprospecting Natural Products.

Descriptions of the use of natural products in traditional medicine have served as starting points for new therapeutics. The details of the traditional use of these organisms can provide important information for future drug discovery and development efforts. Recent technologic advances provide the framework to leverage ethnopharmacologic data in the drug discovery process. Information on the traditional harvest, preparation, storage, and administration of the organisms, and the natural products they contain, provides valuable details regarding characteristics of the active compounds. Importantly, researchers can now rapidly analyze and identify the multiple, and often synergistic, compounds contained in these natural products. Although we are entering the acme of ethnopharmacology, where information regarding the traditional use of organisms can provide valuable natural product leads and accelerate the identification of new therapeutics, this ethnopharmacologic resource is threatened by the loss of traditional medicine knowledge and extinction of organisms.

Medicinal plants of the Russian Pharmacopoeia; their history and applications.

ETHNOPHARMACOLOGICAL RELEVANCE: Due to the location of Russia between West and East, Russian phytotherapy has accumulated and adopted approaches that originated in European and Asian traditional medicine. Phytotherapy is an official and separate branch of medicine in Russia; thus, herbal medicinal preparations are considered official medicaments. The aim of the present review is to summarize and critically appraise data concerning plants used in Russian medicine. This review describes the history of herbal medicine in Russia, the current situation and the pharmacological effects of specific plants in the Russian Pharmacopoeia that are not included in the European Pharmacopoeia. MATERIALS AND METHODS: Based on the State Pharmacopoeia of the USSR (11(th) edition), we selected plant species that have not yet been adopted in Western and Central Europe (e.g., selected for inclusion in the European Pharmacopoeia) and systematically searched the scientific literature for data using library catalogs, the online service E-library.ru, and databases such as Medline/Pubmed, Scopus, and the Web of Science regarding species, effectiveness, pharmacological effects, and safety. RESULTS: The Russian Federation follows the State Pharmacopoeia of the USSR (11(th) edition), which contains 83 individual plant monographs. Fifty-one of these plants are also found in the European Pharmacopoeia and have been well studied, but 32 plants are found only in the Pharmacopoeia of the USSR. Many articles about these medicinal plants were never translated in English, and much of the information collected by Russian scientists has never been made available to the international community. Such knowledge can be applied in future studies aimed at a safe, evidence-based use of traditional Russian medicinal plants in European and global phytopharmacotherapy as well as for the discovery of novel leads for drug development. CONCLUSION: The review highlights the therapeutic potential of these Russian phytopharmaceuticals but also highlights cases where concern has been raised about product safety and tolerability, which would aid in supporting their safe use.

What is in a name? The need for accurate scientific nomenclature for plants.

ETHNOPHARMACOLOGICAL RELEVANCE: To avoid ambiguities and error, ethnopharmacological and any other research on plants requires precise and appropriate use of botanical scientific nomenclature. AIMS: This paper explores problems and impacts of ambiguous or erroneous use of botanical scientific nomenclature in ethnopharmacological studies. It suggests how the frequency and impact of such errors can be reduced. APPROACH AND METHODS: We assessed 214 articles published in the three first volumes of the Journal of Ethnopharmacology in 2012: 140(1) to 141 (3) and 214 articles in Phytomedicine (2012-2013): 19 (5) to 20 (7). RESULTS: Amongst the articles reviewed 308 articles cited plant names incorrectly. Among the articles studied 9178 Latin scientific names were cited and 3445 were incorrect in some respect. Simple principles applied in a systematic way and used together with open-access reference resources could help authors, referees and editors of ethnopharmacological, phytochemical, toxicological and clinical studies to reduce ambiguity about the identity and name of the species involved and thus significantly improve the quality of the final publication. CONCLUSIONS: We have identified a series of key steps needed to solve the taxonomic ambiguities and errors. Aside from reinforcing existing policies, journals will have to implement better tools to ensure the proper authentication of materials. The new electronic publishing environments offer novel ways to develop such botanical-taxonomic tools.

Perturbation of polyamine catabolism affects grape ripening of Vitis vinifera cv. Trincadeira.

Grapes are economically the most important fruit worldwide. However, the complexity of biological events that lead to ripening of nonclimacteric fruits is not fully understood, particularly the role of polyamines' catabolism. The transcriptional and metabolic profilings complemented with biochemical data were studied during ripening of Trincadeira grapes submitted to guazatine treatment, a potent inhibitor of polyamine oxidase activity. The mRNA expression profiles of one time point (EL 38) corresponding to harvest stage was compared between mock and guazatine treatments using Affymetrix GrapeGen(®) genome array. A total of 2113 probesets (1880 unigenes) were differentially expressed between these samples. Quantitative RT-PCR validated microarrays results being carried out for EL 35 (véraison berries), EL 36 (ripe berries) and EL 38 (harvest stage berries). Metabolic profiling using HPLC and (1)H NMR spectroscopy showed increase of putrescine, proline, threonine and 1-O-ethyl-ß-glucoside in guazatine treated samples. Genes involved in amino acid, carbohydrate and water transport were down-regulated in guazatine treated samples suggesting that the strong dehydrated phenotype obtained in guazatine treated samples may be due to impaired transport mechanisms. Genes involved in terpenes' metabolism were differentially expressed between guazatine and mock treated samples. Altogether, results support an important role of polyamine catabolism in grape ripening namely in cell expansion and aroma development.

In vivo antiprostate tumor potential of Vernonia guineensis Benth. (Asteraceae) tuber extract (VGDE) and the cytotoxicity of its major compound pentaisovaleryl sucrose.

ETHNOPHARMACOLOGICAL RELEVANCE: Vernonia guineensis Benth. (Asteraceae) root decoction is used in folk medicine in Cameroon to treat some ailments including prostate cancer. The aim of this study was to validate the claimed antiprostate cancer activity of Vernonia guineensis Benth. in vivo and to investigate the cytotoxicity of a pentaisovaleryl sucrose isolated from Vernonia guineensis on some cancer cell lines. MATERIALS AND METHODS: A crude dichloromethane extract of Vernonia guineensis (VGDE) was used for this study. For in vivo antiprostate cancer efficacy, nude mice (n=16) were injected subcutaneously with prostate cancer PC-3 cells. Upon the formation of the xenograft tumors, the mice were divided into two equal groups with approximately the same mean tumor volume per group. One group was treated with VGDE orally (500 mg/kg) and the other with a vehicle control for 30 days. Body weight and tumor volumes were measured 2× a week and on the 33rd day, the mice were euthanized and tumors harvested and weighed. For the cytotoxicity study, the WST-1 assay was used to determine the activity of pentaisovaleryl sucrose previously isolated from VGDE. The cancer cell lines used in the cytotoxicity study included breast, colon, leukemia, lung, melanoma, ovarian and prostate. RESULTS: Prostate cancer (PC-3) xenograft tumors treated with VGDE showed a significant decrease in tumor size (P=0.0295) compared to control. Pentaisovaleryl sucrose also demonstrated cytotoxicity against various cancer cell lines with IC50 values as follows: MDA-MD-231-6.66µM; MCF-7-7.50 µM; HCT116-14.12 µM; A549-5.76 µM; HL60-6.43 µM; A375-8.64 µM; OVCAR3-9.53 µM; Capan1-7.13 µM; Mia-Paca 6.47 µM. CONCLUSION: VGDE does possess in vivo activity against prostate tumor and has potential for development into a natural product for the treatment of prostate cancer. This study thus provides preliminary validation for the folk use of Vernonia guineensis against prostate conditions. Further in vivo studies are however required to confirm these results and to understand the mechanism of action of VGDE and the in vivo efficacy of pentaisovaleryl sucrose.

The use of bio-guided fractionation to explore the use of leftover biomass in Dutch flower bulb production as allelochemicals against weeds.

A major problem in flower bulb cultivation is weed control. Synthetic herbicides are mainly used, although they cause a range of problems, and integrated weed control through application of naturally occurring allelochemicals would be highly desirable. Flower bulb production creates large amounts of leftover biomass. Utilizing this source for weed control may provide new applications of the bulb crops. We therefore screened 33 flower bulb extracts for allelochemical activity against weeds. Several methanol and chloroform extracts were observed to inhibit germination and growth of Senecio vulgaris L. and Lolium perenne L., as representatives of di- and mono-cotyledonous weeds, respectively. Narciclasine was identified as the bioactive compound in Narcissus. The extract of Amaryllis belladonna L. was equally active, but did not contain any narciclasine. Bioassay-guided fractionation of the A. belladonna extract resulted in the identification of lycorine as the bio-active compound. The IC50 measured for radicle growth inhibition was 0.10 µM for narciclasine and 0.93 µM for lycorine, compared to 0.11 mM of chlorpropham, a synthetic herbicide. Therefore, the leftover biomass from the spring bulb industry represents an interesting potential source for promising allelochemicals for further studies on weed growth inhibition.

Antiplasmodial activity of sesquiterpene lactones and a sucrose ester from Vernonia guineensis Benth. (Asteraceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Aqueous preparations of Vernonia guineensis Benth. (Asteraceae) are used in Cameroonian folk medicine as a general stimulant and to treat various illnesses and conditions including malaria, bacterial infections and helminthic infestations. MATERIALS AND METHODS: Ten gram samples of the leaf and tuber powders of Vernonia guineensis were extracted separately using dichloromethane, methanol and distilled water. The extracts were dried in vacuo and used in bioassays. These extracts and three compounds previously isolated from Vernonia guineensis [vernopicrin (1), vernomelitensin (2) and pentaisovalerylsucrose (3)] were screened for antiplasmodial activity against chloroquine (CQ)-sensitive (Hb3) and CQ-resistant (Dd2) Plasmodium falciparum lines. RESULTS: Crude extracts and pure compounds from Vernonia guineensis showed antiplasmodial activity against both Hb3 and Dd2. The IC50 values of extracts ranged from 1.64 to 27.2 µg/ml for Hb3 and 1.82-30.0 µg/ml for Dd2; those for compounds 1, 2 and 3 ranged from 0.47 to 1.62 µg/ml (1364-1774 nM) for Hb3 and 0.57-1.50 µg/ml (1644-2332nM) for Dd2. None of the crude extracts or pure compounds was observed to exert toxic effects on the erythrocytes used to cultivate the Plasmodium falciparum lines. CONCLUSION: In Cameroonian folk medicine, Vernonia guineensis may be used to treat malaria in part due to the antiplasmodial activity of sesquiterpene lactones (1, 2), a sucrose ester (3) and perhaps other compounds present in crude plant extracts. Exploring the safety and antiplasmodial efficacy of these compounds in vivo requires further study.

Cytotoxic sesquiterpene lactones from the leaves of Vernonia guineensis Benth. (Asteraceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Vernonia guineensis Benth. (Asteraceae) preparations are used in folk medicine in Cameroon to treat a number of ailments, including prostate cancer and malaria, and is used as an anthelmintic, adaptogen and antidote. The aim of this study was to continue the validation of the activity of Vernonia guineensis Benth. extracts and isolated molecules against cancer cell lines following the previous isolation of an anti-prostate cancer sugar ester from the root extract. MATERIALS AND METHODS: Acetone extracts of Vernonia guineensis Benth. leaves were tested for activity against 10 cancer cell lines (Breast-MDA-MB-231, Breast-MCF-7, Colon-HCT-116, Leukemia-HL-60, Lung-A549, Melanoma-A375, Ovarian-OVCAR3, Pancreas-Mia-paca, Prostate-PC-3 and Prostate-DU-145). The acetone extract was subjected to bioactivity guided fractionation. Anti-proliferation and clonogenic activity of the isolated compounds were tested. The WST-1 assay was used for the anti-proliferation activity, while the standard clonogenic test was used to determine the clonogenic activity. RESULTS: The acetone extract of Vernonia guineensis Benth. demonstrated in vitro activity ranging from IC50 4-26µg/mL against the 10 cell lines. Activity guided fractionation of this extract yielded two sesquiterpene lactones, isolated for the first time from the genus Vernonia. The compounds were characterized using spectroscopic experiments, including a combination of 1D and 2D NMR data. Vernopicrin (1) and Vernomelitensin (2) demonstrated in vitro activity against human cancer cell lines with IC50 ranging from 0.35-2.04µM (P<0.05) and 0.13-1.5µM (P<0.05), respectively, between the most and least sensitive cell lines for each compound. Vernopicrin was most active against the human melanoma (A375) cell line and least active against the lung cancer (A549) cell line, while Vernomelitensin was also most active against the human melanoma (A375) cell line and least active against the breast cancer (MCF-7) cell line. Both compounds also demonstrated anticlonogenic activity. CONCLUSION: The cytotoxicity demonstrated by the crude extract and isolated sesquiterpenes against cancer cell lines highlights the medicinal potential of V. guineensis. The selective anti-proliferation and dose dependent anticlonogenic activities suggest that the identified sesquiterpenes could be potential antitumor agents.