Selection methodology with scoring system: application to Mexican plants producing podophyllotoxin related lignans

Phylogenetic Analysis and Flower Color Evolution of the Subfamily Linoideae (Linaceae)

The taxonomy of the subfamily Linoideae at the intergeneric and section levels has been questioned throughout the years, and the evolution of floral characters remains poorly understood. In particular, the evolution of flower color is still uncertain, despite its ecological importance and being one of the most variable and striking traits in Angiospermae. We evaluated the phylogenetic relationships of the genera and sections and used the phylogeny to reconstruct the ancestral state of flower color. The results suggest reevaluating the taxonomic status of segregated genera and re-incorporating them into Linum. Four of the five sections currently accepted were recovered as monophyletic (Cathartolinum, Dasylinum, Linum, and Syllinum). We propose accepting the section Stellerolinon and reevaluating Linopsis, whose representatives were recovered in three separate clades. The ancestral flower color for Linoideae was yellow-white. The flower colors purple and yellow-white were recovered at the deepest nodes of the two main clades. Pink, blue, and red colors were the most recent to evolve. These results appear to be related to diversification events, biogeographical history, and ecological aspects of the subfamily. Our reconstruction constitutes the first plausible scenario that explores the evolution of flower color, leading to new testable hypotheses for future research on the flax group.

Traditional Uses, Phytochemistry, and Bioactivities of Mesosphaerum suaveolens (L.) Kuntze

Mesosphaerum suaveolens (L.) Kuntze is a species widely used traditionally in the treatment of ailments, such as stomach pain, hemorrhoids, cough, verminosis, ulcer, liver disease, fever, influenza, nasal congestion, and inflammation. This review aims to provide a survey of available information on seven international electronic databases (Google Scholar, Medline, ResearchGate, Web of Science, Scopus, Science Direct, and PubMed) about botanical aspects, traditional uses, phytochemistry, and biological activities of M. suaveolens. Mesosphaerum suaveolens is a tropical America native species, but it can be found in several parts of the world as a ruderal plant. The species is the most studied species of the genus Lamiaceae due its phytochemical aspect, especially regarding the chemical composition of its essential oil. Besides the essential oils, M. suaveolens is a source of numerous secondary compounds such as triterpenes, diterpenes, and phenolic compounds, which are related to its biological activities, such as allelopathic, antibacterial, antifungal, insecticidal, and larvicidal activities as described in the literature.

Exploring Multifunctional Bioactive Components from Podophyllum sinense Using Multi-Target Ultrafiltration

Podophyllum sinense (P. sinense) has been used as a traditional herbal medicine for ages due to its extensive pharmaceutical activities, including antiproliferative, anti-inflammatory, antiviral, insecticidal effects, etc. Nevertheless, the specific bioactive constituents responsible for its antiproliferative, anti-inflammatory, and antiviral activities remain elusive, owing to its complicated and diversified chemical components. In order to explore these specific bioactive components and their potential interaction targets, affinity ultrafiltration with multiple drug targets coupled with high performance liquid chromatography/mass spectrometry (UF–HPLC/MS) strategy was developed to rapidly screen out and identify bioactive compounds against four well-known drug targets that are correlated to the application of P. sinense as a traditional medicine, namely, Topo I, Topo II, COX-2, and ACE2. As a result, 7, 10, 6, and 7 phytochemicals were screened out as the potential Topo I, Topo II, COX-2, and ACE2 ligands, respectively. Further confirmation of these potential bioactive components with antiproliferative and COX-2 inhibitory assays in vitro was also implemented. Herein, diphyllin and podophyllotoxin with higher EF values demonstrated higher inhibitory rates against A549 and HT-29 cells as compared with those of 5-FU and etoposide. The IC₅₀ values of diphyllin were calculated at 6.46 ± 1.79 and 30.73 ± 0.56 μM on A549 and HT-29 cells, respectively. Moreover, diphyllin exhibited good COX-2 inhibitory activity with the IC₅₀ value at 1.29 ± 0.14 μM, whereas indomethacin was 1.22 ± 0.08 μM. In addition, those representative constituents with good affinity on Topo I, Topo II, COX-2, or ACE2, such as diphyllin, podophyllotoxin, and diphyllin O-glucoside, were further validated with molecular docking analysis. Above all, the integrated method of UF–HPLC/MS with multiple drug targets rapidly singled out multi-target bioactive components and partly elucidated their action mechanisms regarding its multiple pharmacological effects from P. sinense, which could provide valuable information about its further development for the new multi-target drug discovery from natural medicines.

Podophyllotoxin: History, Recent Advances and Future Prospects

Podophyllotoxin, along with its various derivatives and congeners are widely recognized as broad-spectrum pharmacologically active compounds. Etoposide, for instance, is the frontline chemotherapeutic drug used against various cancers due to its superior anticancer activity. It has recently been redeveloped for the purpose of treating cytokine storm in COVID-19 patients. Podophyllotoxin and its naturally occurring congeners have low bioavailability and almost all these initially discovered compounds cause systemic toxicity and development of drug resistance. Moreover, the production of synthetic derivatives that could suffice for the clinical limitations of these naturally occurring compounds is not economically feasible. These challenges demanded continuous devotions towards improving the druggability of these drugs and continue to seek structure-optimization strategies. The discovery of renewable sources including microbial origin for podophyllotoxin is another possible approach. This review focuses on the exigency of innovation and research required in the global R&D and pharmaceutical industry for podophyllotoxin and related compounds based on recent scientific findings and market predictions.

Secure and Sustainable Sourcing of Plant Tissues for the Exhaustive Exploration of Their Chemodiversity

The main challenge of plant chemical diversity exploration is how to develop tools to study exhaustively plant tissues. Their sustainable sourcing is a limitation as bioguided strategies and dereplication need quite large amounts of plant material. We examine if alternative solutions could overcome these difficulties by obtaining a secure, sustainable, and scalable source of tissues able to biosynthesize an array of metabolites. As this approach would be as independent of the botanical origin as possible, we chose eight plant species from different families. We applied a four steps culture establishment procedure, monitoring targeted compounds through mass spectrometry-based analytical methods. We also characterized the capacities of leaf explants in culture to produce diverse secondary metabolites. In vitro cultures were successfully established for six species with leaf explants still producing a diversity of compounds after the culture establishment procedure. Furthermore, explants from leaves of axenic plantlets were also analyzed. The detection of marker compounds was confirmed after six days in culture for all tested species. Our results show that the first stage of this approach aiming at easing exploration of plant chemodiversity was completed, and leaf tissues could offer an interesting alternative providing a constant source of natural compounds.

In vitro Synergy of Polyphenolic Extracts From Honey, Myrtle and Pomegranate Against Oral Pathogens, S. mutans and R. dentocariosa

The increasing incidence rate of oral diseases, the wide spread of antimicrobial resistance, and the adverse effects of conventional antibiotics mean alternative prevention and treatment options are needed to counteract oral pathogens. In this regard, our study aims to evaluate the antibacterial activity of polyphenolic extracts prepared from acacia honey, myrtle leaves, and pomegranate peel against cariogenic bacteria, such as Streptococcus mutans and Rothia dentocariosa. The chemical-physical parameters of acacia honey and the RP-HPLC polyphenolic profile of pomegranate peel extract have been previously described in our studies, while the characterization of myrtle extract, performed by HPLC analysis, is reported here. All the extracts were used singly and in binary combinations to highlight any synergistic effects. Moreover, the extracts were tested in association with amoxicillin to evaluate their ability to reduce the effective dose of this drug in vitro. The values of minimal inhibitory concentrations and minimal bactericidal concentrations have been used to quantitatively measure the antibacterial activity of the single extracts, while the fractional inhibitory concentration index has been considered as predictor of in vitro anticariogenic synergistic effects. Finally, a time-kill curve method allowed for the evaluation of the bactericidal efficacy of the combined extracts. The microbiological tests suggest that acacia honey, myrtle, and pomegranate extracts are able to inhibit the cariogenic bacteria, also with synergistic effects. This study provides useful and encouraging results for the use of natural extract combinations alone or in association with antibiotics (adjuvant therapy) as a valid alternative for the prevention and treatment of oral infectious diseases.

Unraveling Plant Natural Chemical Diversity for Drug Discovery Purposes

The screening and testing of extracts against a variety of pharmacological targets in order to benefit from the immense natural chemical diversity is a concern in many laboratories worldwide. And several successes have been recorded in finding new actives in natural products, some of which have become new drugs or new sources of inspiration for drugs. But in view of the vast amount of research on the subject, it is surprising that not more drug candidates were found. In our view, it is fundamental to reflect upon the approaches of such drug discovery programs and the technical processes that are used, along with their inherent difficulties and biases. Based on an extensive survey of recent publications, we discuss the origin and the variety of natural chemical diversity as well as the strategies to having the potential to embrace this diversity. It seemed to us that some of the difficulties of the area could be related with the technical approaches that are used, so the present review begins with synthetizing some of the more used discovery strategies, exemplifying some key points, in order to address some of their limitations. It appears that one of the challenges of natural product-based drug discovery programs should be an easier access to renewable sources of plant-derived products. Maximizing the use of the data together with the exploration of chemical diversity while working on reasonable supply of natural product-based entities could be a way to answer this challenge. We suggested alternative ways to access and explore part of this chemical diversity with in vitro cultures. We also reinforced how important it was organizing and making available this worldwide knowledge in an "inventory" of natural products and their sources. And finally, we focused on strategies based on synthetic biology and syntheses that allow reaching industrial scale supply. Approaches based on the opportunities lying in untapped natural plant chemical diversity are also considered.

Cytotoxic activity and triterpenes content of nine Mexican species of Bursera

The genus Bursera (Burseraceae) is considered an interesting source of antitumour compounds. This study aimed to evaluate the cytotoxic activity of the dichloromethane-soluble extracts from the bark of nine Mexican Bursera species. The chemical components of the extracts were determined by NMR and mass spectroscopy, whereas its cytotoxicity was tested using the sulphorhodamine (SRB) method on seven cell lines. Triterpenes and fatty acids were the most abundant components found in the extracts. A quantification by HPTLC - densitometry, showed that the species B. copallifera had the highest content of amyrins (287 µg/mg extract) followed by B. submoniliformis (159.5 µg/mg) and B. bicolor (156.5 µg/mg). Regarding cytotoxicicity, the species B. bicolor caused the highest growth inhibition (>90%) in colon (HCT-15) and lung (SK-LU1) lines; while B. fagaroides, B. grandifolia, B. morelensis, B. bicolor and B. linanoe were active in the SK-LU1cell line.

Dereplication of podophyllotoxin and related cytotoxic lignans in Hyptis verticillata by ultra-high-performance liquid chromatography tandem mass spectrometry

INTRODUCTION

Hyptis verticillata Jacq. (Lamiaceae) is a Mexican medicinal plant for the treatment of skin infections and illness affecting the respiratory and gastrointestinal systems.

OBJECTIVE

To associate the efficient resolution provided by ultra-high-performance liquid chromatography combined to the accuracy of a hybrid Fourier-transform (FT) mass spectrometer in order to dereplicate podophyllotoxin-type lignans in a plant extract.

METHODS

An ultra-high-performance liquid chromatography-photodiode array-high resolution electrospray ionisation tandem mass spectrometry (UHPLC-PDA-HRESI-MS/MS) method was applied in an Orbitrap hybrid FT spectrometer for dereplication of podophyllotoxin and related cytotoxic lignans in wild bushmint. This procedure included high-resolution mass values for positively charged ions [M + H]⁺ and [M + NH₄ ]⁺ , MS/MS data, and comparison of UV maxima and retention times with pure compounds.

RESULTS

Podophyllotoxin in addition to seven aryltetralins, four arylnaphthalenes, and one dibenzylbutyrolactone were dereplicated from the methanol extract in a short-time analysis (5 min). 4'-O-Demethyl-dehydro-deoxypodophyllotoxin was identified as a new natural product.

CONCLUSION

The applied UHPLC-MS/MS dereplication method is suitable for a rapid analysis of podophyllotoxin-type lignans and the resulting chemical fingerprinting could be valuable in quality control of herbal drugs and their phytopharmaceuticals.

Improving the production of podophyllotoxin in hairy roots of Hyptis suaveolens induced from regenerated plantlets

Ten Hyptis suaveolens hairy root lines were established by infecting nodal explants with K599+pGus-GFP+ and ATCC15834+pTDT strains from Agrobacterium rhizogenes. Genetic transformation was confirmed by epifluorescence and plagiotropic hairy root growth in absence of growth regulators. Cytotoxicity was determined using the sulforhodamine B method, and the production of podophyllotoxin (PTOX) was measured by high performance thin layer chromatography scanning. Through these methodologies, HsTD10 was identified as the hairy root line with the highest cytotoxicity and PTOX production, which was corroborated by liquid chromatography-mass spectrometry and micrOTOF-Q II. A suspension culture of HsTD10 was established in which PTOX and carbohydrate consumption during growth kinetics were quantified by high-performance liquid chromatography. Procedures to increase the production and retrieval of PTOX in the HsTD10 line included selection of culture medium, addition of thiamine, and modification of the PTOX extraction method. The best combination of these variables was MS medium at 75% of its components with the addition of 2 mg L^-1 of thiamine, extraction with methanol-dichloromethane, and sonication at 40 ± 5°C. During kinetics, growth-associated PTOX accumulation was observed. The specific growth rate (μ) was 0.11 d^-1. The highest concentration of PTOX obtained with HsTD10 (5.6 mg g^-1 DW) was 100 times higher than that reported for roots of wild plants and 56 times higher than that for in vitro nontransformed roots of H. suaveolens.

Bursera copallifera Extracts Have Cytotoxic and Migration-Inhibitory Effects in Breast Cancer Cell Lines

Plants from the Bursera genus are widely distributed in the tropical dry forests of Mexico. In traditional medicine, extracts from different species of Bursera have been used for a wide range of biological activities, including the treatment of cancer-related symptoms. Compounds present in the Bursera genus include lignans, flavonoids, steroids, short-chain aliphatic alkanes, acetates, alcohols, ketones, and terpenoids. In some instances, secondary metabolites of these classes of compounds may induce cytotoxicity, and therefore we sought to investigate the effects of B. copallifera leaf extracts in breast cancer cell lines to evaluate their potential therapeutic value for the treatment of breast cancer, one of the most prevalent types of cancer in women worldwide. Two B. copallifera leaf extracts exerted cytotoxic effects on both the MCF7 and MDA-MB-231 breast cancer cell line models. The cytotoxic effect was more evident in the MDA-MB-231 triple negative cell line inhibiting also the migration of these cells. We identified hydroxycinnamic acid and flavonol derivatives as major phenolic components of the extracts. Our results strongly suggest a potential use of the Bursera leaf extracts rich in phenolic compounds, their individual phenolic compounds, or their combinations for the treatment of breast cancer.

Use of traditional herbal medicine as an alternative in dental treatment in Mexican dentistry: a review

CONTEXT

Herbal therapies are used worldwide to treat health conditions. In Mexico, generations have used them to treat gingivitis, periodontitis, mouth infections, and discoloured teeth. However, few studies have collected scientific evidence on their effects.

OBJECTIVE

This study aimed at searching and compiling scientific evidence of alternative oral and dental treatments using medicinal herbs from Mexico.

METHODS

We collected various Mexican medicinal plants used in the dental treatment from the database of the Institute of Biology at the National Autonomous University of Mexico. To correlate with existing scientific evidence, we used the PubMed database with the key term '(scientific name) and (oral or dental)'.

RESULTS

Mexico has various medical herbs with antibacterial and antimicrobial properties, according to ancestral medicinal books and healers. Despite a paucity of experimental research demonstrating the antibacterial, antimicrobial, and antiplaque effects of these Mexican plants, they could still be useful as an alternative treatment of several periodontal diseases or as anticariogenic agents. However, the number of studies supporting their uses and effects remains insufficient.

DISCUSSION AND CONCLUSION

It is important for the health of consumers to scientifically demonstrate the real effects of natural medicine, as well as clarify and establish their possible therapeutic applications. Through this bibliographical revision, we found papers that testify or refute their ancestral uses, and conclude that the use of plants to treat oral conditions or to add to the dental pharmacological arsenal should be based on experimental studies verifying their suitability for dental treatments.

Anti-inflammatory and antioxidative effects of six pentacyclic triterpenes isolated from the Mexican copal resin of Bursera copallifera

BACKGROUND

Bursera copallifera (Burseraceae) releases a resin known as "copal ancho" which has been used, since pre-Colombian times, as ceremonially burned incense and to treat tooth ache, tumors, arthritis, cold, cough, and various inflammatory conditions; however, its anti-inflammatory potential is poorly studied. The aim of the present study was to isolate, quantify, and to investigate the anti-inflammatory activity of triterpene compounds isolated from the copal resin of B. copallifera.

METHODS

The constituents present in the total resin of B. copallifera were obtained by successive chromatographic procedures, and quantitative analysis was performed by High Performance Liquid Chromatography (HPLC). Anti-inflammatory effects of the isolated triterpenes were investigated to determine their inhibitory effects on phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema in mice, viability and nitric oxide (NO) production inhibition on lipopolysaccharide (LPS)-activated RAW 264.7 macrophages, and inhibition of cyclooxygenase (COX)-1, COX-2 and secretory Phospholipase A2 (sPLA2) activities in vitro.

RESULTS

Quantitative phytochemical analysis of the copal resin showed the presence of six pentacyclic triterpenes of which, 3-epilupeol (59.75 % yield) and α-amyrin (21.1 % yield) are the most abundant. Among the isolated triterpenes, 3-epilupeol formiate (Inhibitory Concentration 50 % (IC50) = 0.96 μmol), α.amyrin acetate (IC50 = 1.17 μmol), lupenone (IC50 = 1.05 μmol), and 3-epilupeol (IC50 = 0.83 μmol) showed marked inhibition of the edema induced by TPA in mice. α-amyrin acetate and 3-epilupeol acetate, at 70 μM, also inhibited the activity of COX-2 by 62.85 and 73.28 % respectively, while α-amyrin and 3-epilupeol were the best inhibitors of the production of NO in LPS-activated RAW 264.7 cells with IC50 values of 15.5 and 8.98 μM respectively, and did not affected its viability. All compounds moderately inhibited the activity of PLA2.

CONCLUSIONS

This work supports the folk use of B. copallifera and provides the basis for future investigations about the therapeutic use of this resin in treating inflammation.

Medicinal plants used in Mexican traditional medicine for the treatment of colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Cancer cases numbers are increasing worldwide positioning this disease as the second cause of mortality for both sexes. Medicinal plants have been used in the fight against cancer as the basis for drug discovery and nowadays more than 70% of anticancer drugs have a natural origin. Mexico is regarded for its cultural and biological diversity, which is reflected in the vast traditional knowledge of herbal remedies. In this review we examined herbal remedies employed in colorectal cancer treatment (CRC).

AIM OF THE STUDY

The goal of this work was to gather scientific reports of plants used in Mexican traditional medicine for CRC treatment.

MATERIALS AND METHODS

We performed a search on scientific literature databases using as keywords: "colon cancer", "gastric cancer", "cytotoxicity", studies "in vitro and in vivo", in combination with "Mexican medicinal plants" or "Mexican herbal remedies". The selection criteria of cytotoxic activity for extracts or pure compounds was based on the National Cancer Institute of USA recommendations of effective dose 50 (ED50) of ≤20μg/mL and ≤4μg/mL, respectively.

RESULTS

In this review we report 25 botanic families and 39 species of plants used for the treatment of colon cancer in Mexico with evidence in studies in vitro and in vivo.

CONCLUSIONS

Medicinal plants are still a great source of novel chemical structures with antineoplastic potential as it is proven in this work. The selection criteria and activity was narrowed for methodological purposes, nevertheless, drug discovery of natural origin continues to be a highly attractive R&D strategy.

Anti-inflammatory and cytotoxic activities of Bursera copallifera

Background:

The plant species Bursera copallifera (DC) bullock is used in traditional medicine to treat inflammation. The leaves of this plant can be prepared as an infusion to treat migraines, bronchitis, and dental pain

Objective:

The purpose of this study was to determine the anti-inflammatory and cytotoxic activities of organic extracts from the stems, stem bark, and leaves of B. copallifera, which was selected based on the knowledge of its traditional use.

Materials and Methods:

We evaluated the ability of extracts to inhibit mouse ear inflammation in response to topical application of 12-O tetradecanoylphorbol-13-acetate. The extracts with anti-inflammatory activity were evaluated for their inhibition of pro-inflammatory enzymes. In addition, the in vitro cytotoxic activities of the organic extracts were evaluated using the sulforhodamine B assay.

Results:

The hydroalcoholic extract of the stems (HAS) exhibited an anti-inflammatory activity of 54.3% (0.5 mg/ear), whereas the anti-inflammatory activity of the dichloromethane-methanol extract from the leaves (DMeL) was 55.4% at a dose of 0.1 mg/ear. Methanol extract from the leaves (MeL) showed the highest anti-inflammatory activity (IC₅₀ = 4.4 μg/mL), hydroalcoholic extract of leaves, and DMeL also reduce the enzyme activity, (IC₅₀ = 6.5 μg/mL, IC₅₀ = 5.7 μg/mL), respectively, from stems HAS exhibit activity at the evaluated concentrations (IC₅₀ =6.4 μg/mL). The hydroalcoholic extract of the stems exhibited the highest cytotoxic activity against a breast adenocarcinoma cell line (MCF7, IC₅₀ = 0.90 μg/mL), whereas DMeL exhibited an IC₅₀ value of 19.9 μg/mL.

Conclusion:

In conclusion, extracts from leaves and stems inhibited cyclooxygenase-1, which is the target enzyme for nonsteroidal anti inflammatory drugs, and some of these extracts demonstrated substantial antiproliferative effects against the MCF7 cell line. These results validate the traditional use of B. copallifera.

Cytotoxic Activity and Chemical Composition of the Root Extract from the Mexican Species Linum scabrellum: Mechanism of Action of the Active Compound 6-Methoxypodophyllotoxin

The cytotoxic activity and the chemical composition of the dichloromethane/methanol root extract of Linum scabrellum Planchon (Linaceae) were analyzed. Using NMR spectra and mass spectrometry analyses of the extract we identified eight main constituents: oleic acid (1), octadecenoic acid (2), stigmasterol (3), α-amyrin (4), pinoresinol (5), 6 methoxypodophyllotoxin (6), coniferin (7), and 6-methoxypodophyllotoxin-7-O-β-D-glucopyranoside (8). By using the sulforhodamine B assay, an important cytotoxic activity against four human cancer cell lines, HF6 colon (IC50 = 0.57 μg/mL), MCF7 breast (IC50 = 0.56 μg/mL), PC3 prostate (IC50 = 1.60 μg/mL), and SiHa cervical (IC50 = 1.54 μg/mL), as well as toward the normal fibroblasts line HFS-30 IC50 = 1.02 μg/mL was demonstrated. Compound 6 (6-methoxypodophyllotoxin) was responsible for the cytotoxic activity exhibiting an IC50 value range of 0.0632 to 2.7433 µg/mL against the tested cell lines. Cell cycle studies with compound 6 exhibited a cell arrest in G2/M of the prostate PC3 cancer cell line. Microtubule disruption studies demonstrated that compound 6 inhibited the polymerization of tubulin through its binding to the colchicine site (binding constant K b = 7.6 × 10(6) M(-1)). A dose-response apoptotic effect was also observed. This work constitutes the first investigation reporting the chemical composition of L. scabrellum and the first study determining the mechanism of action of compound 6.

Production of podophyllotoxin from roots and plantlets of Hyptis suaveolens cultivated in vitro

BACKGROUND

Hyptis suaveolens was an important source of food and medicines in pre-hispanic Mιxico and is actually used popularly to treat respiratory and skin diseases, fever, pain, and cramps, between other ailments. In 2008 the presence of podophyllotoxin (PTOX) was reported in this plant.

OBJECTIVE

To establish in vitro cultures of H. suaveolens able to produce PTOX.

MATERIALS AND METHODS

Explants of H. suaveolens were cultivated in Murashige and Skoog (MS) medium supplemented with different concentrations of the phytohormones 6-benzylaminopurine (6-BAP), 2,4-dichlorophenoxyacetic acid (2,4-D), 1-naphthaleneacetic acid (NAA) and kinetin (Kin), in order to induce the production of podophyllotoxin. Root cultures without hormones were also established and the quantification of PTOX was performed by HPLC analysis.

RESULTS

The presence of growth regulators during in vitro cultivation of H. suaveolens, provoked morphological variations in explants, and induced the accumulation of different levels of PTOX. Roots grown without phytohormones accumulated PTOX at 0.013% dry weight (DW), while in three of the callus cultures cell lines growing together with roots, PTOX accumulated at concentrations of 0.003, 0.005 and 0.006% DW when NAA was combined with either Kin or BAP. In wild plant material PTOX was present in trace amounts in the aerial parts, while in the roots it was found at 0.005% DW.

CONCLUSION

This study demonstrated that although it is possible to obtain PTOX in a variety of in vitro cultures of H. suaveolens, in vitro roots grown without the addition of growth regulators were better producers of PTOX.

Bryonia dioica aqueous extract induces apoptosis through mitochondrial intrinsic pathway in BL41 Burkitt's lymphoma cells

ETHNOPHARMACOLOGICAL RELEVANCE

Bryonia dioica Jacq. is a climbing perennial herb with tuberous roots which is widely used in traditional medicine in Algeria for the treatment of cancers; it belongs to the genus Bryonia (Cucurbitaceae).

AIM OF THE STUDY

To investigate the cytotoxic and apoptogenic activities, the phytochemical composition and acute toxicity of the aqueous extract of Bryonia dioica roots growing in Algeria.

MATERIALS AND METHODS

Dried roots of Bryonia dioica were extracted with water (decoction). The cytotoxic effects of the aqueous extract in the Burkitt's lymphoma BL41 cell lines were evaluated by flow cytometry. Apoptosis induction was assessed by two corroborative assays; propidium iodide (PI) staining of cell DNA and flow cytometric light scatter analysis. The mitochondria membrane potential was investigated using a fluorescent dye DIOC6. The expression of caspases-3, -8, -9 and PARP was assessed by Western blot. The phytochemical screening of the roots of Bryonia dioica was performed using qualitative phytochemical standard procedures.

RESULTS

The Bryonia dioica aqueous extract induced cell death in a dose-dependent manner. The IC50 of Bryonia dioica aqueous extract was estimated to be approximately 15, 63μg/ml. This was accompanied by induction of apoptosis, activation of caspase-3 and -9, cleavage of PARP and loss of mitochondria membrane potential. Furthermore, the phytochemical screening of roots of Bryonia dioica showed the presence of various bioactive such as polyphenols, sterols and triterpenes, alkaloids, c-heterosides, carbohydrates and saponins.

CONCLUSION

The aqueous extract of Bryonia dioica induces apoptosis in the Burkitt's lymphoma BL41 cell lines via the mitochondrial pathway. The flavonoids, sterols and triterpens detected could be responsible for the cytotoxic and apoptogenic activities of the aqueous extract of Bryonia dioica. These findings suggest that Bryonia dioica could be considered as a promising source for developing novel therapeutics against Burkitt's lymphoma.

Absolute configuration of podophyllotoxin related lignans from Bursera fagaroides using vibrational circular dichroism

The ethanol extract from the dried exudate of Bursera fagaroides (Burseraceae) showed significant cytotoxic activity in the HT-29 (human colon adenocarcinoma) test system. The extract provided four podophyllotoxin related lignans, identified as (7'R,8R,8'R)-(-)-deoxypodophyllotoxin (3), (7'R,8R,8'R)-(-)-morelensin (4), (8R,8'R)-(-)-yatein (5), and (8R,8'R)-(-)-5'-desmethoxyyatein (6), whose spectroscopic and chiroptical properties were compared with those of (7R,7'R,8R,8'R)-(-)-podophyllotoxin (1) and its acetyl derivative (2). Their absolute configurations were assigned by comparison of the vibrational circular dichroism spectra of 1 and 3 with those obtained by density functional theory calculations.

Mexican medicinal plants used for cancer treatment: pharmacological, phytochemical and ethnobotanical studies

AIM OF THE STUDY

This review provides a summary of Mexican medicinal flora in terms of ethnobotanical, pharmacology, and chemistry of natural products related to anticancer activity.

MATERIALS AND METHODS

Bibliographic investigation was carried out by analyzing recognized books and peer-reviewed papers, consulting worldwide accepted scientific databases from the last five decades. Mexican plants with attributed anti-cancer properties were classified into six groups: (a) plant extracts that have been evaluated for cytotoxic effects, (b) plant extracts that have documented anti-tumoral effects, (c) plants with active compounds tested on cancer cell lines, (d) plants with novel active compounds found only in Mexican species, (e) plants with active compounds that have been assayed on animal models and (f) plants with anti-cancer ethnopharmacological references but without scientific studies.

RESULTS

Three hundred plant species belonging to 90 botanical families used for cancer treatment have been recorded, of which only 181 have been experimentally analyzed. The remaining 119 plant species are in use in empirical treatment of diseases consistent with cancer symptomatology. Only 88 of the plant extracts experimentally studied in in vitro cellular models have demonstrated active cytotoxic effects in at least one cancer cell line, and 14 out of the 88 have also been tested in vivo with the results that one of them demonstrated anti-neoplasic effects. A total of 187 compounds, belonging to 19 types of plant secondary metabolites, have been isolated from 51 plant extracts with active cytotoxic effects, but only 77 of these compounds (41%) have demonstrated cytoxicity. Seventeen of these active principles have not been reported in other plant species. However, only 5 compounds have been evaluated in vivo, and 3 of them could be considered as active.

CONCLUSION

Clearly, this review indicates that it is time to increase the number of experimental studies and to begin to conduct clinical trials with those Mexican plants and its active compounds selected by in vitro and in vivo activities. Also, the mechanisms of action by which plant extracts and their active compounds exert anti-cancer effects remain to be studied.

Recent advances on HPLC/MS in medicinal plant analysis

With gaining popularity of herbal remedies worldwide, the need of assuring safety and efficacy of these products increases as well. By nature they are complex matrices, comprising a multitude of compounds, which are prone to variation due to environmental factors and manufacturing conditions. Furthermore, many traditional preparations compose of multiple herbs, so that only highly selective, sensitive and versatile analytical techniques will be suitable for quality control purposes. By hyphenating high performance liquid chromatography and mass spectrometry (LC-MS) these high demands are fulfilled, providing the user with a multitude of technical options and applications. This review intends to reflect the impact of LC-MS for medicinal plant analysis focusing on most relevant reports published within the last five years. Commenced by introductory remarks to the different MS approaches most commonly used (e.g. ion trap and time of flight mass analyzers, fragmentation and ionization modes), respective LC-MS applications on the analysis of natural products in medicinal plants, commercial products and biological samples are presented. Methodological aspects like stationary and mobile phase selection or MS settings are discussed, and advantages or limitations of the described techniques are highlighted.