Cinchona Species Research Articles

Quest for malaria management using natural remedies.

Malaria, transmitted through the bite of a Plasmodium-infected Anopheles mosquito, remains a significant global health concern. This review examines the complex life cycle of Plasmodium, emphasizing the role of humans and mosquitoes in its transmission and proliferation. Malarial parasites are transmitted as sporozoites to the human body by biting an infected female Anopheles mosquito. These sporozoites then invade liver cells, multiply, and release merozoites, which infect red blood cells, perpetuating the cycle. As this cycle continues, the affected person starts experiencing the clinical symptoms of the disease. The current treatments for malaria, including chloroquine, artemisinin-based combination therapy, and quinine, are discussed alongside the challenges of drug resistance and misdiagnosis. Although efforts have been made to develop a malarial vaccine, they have so far been unsuccessful. Additionally, the review explores the potential of medicinal plants as remedies for malaria, highlighting the efficacy of compounds derived from Artemisia annua, Cinchona species, and Helianthus annuus L., as well as exploration of plants and phytocompounds like cryptolepine, and isoliquiritigenin against drug-resistant Plasmodium species. Moreover, studies from Pakistan further highlight the diverse vegetal resources utilized in malaria treatment, emphasizing the need for further research into natural remedies. Despite the advantages of herbal medicines, including cost-effectiveness, and fewer side effects; their limitations must be taken into account, including variations in potency and potential drug interactions. The review concludes by advocating for a balanced approach to malaria treatment and prevention, emphasizing the importance of early detection, accurate diagnosis, and integrated efforts to combat the disease in the endemic regions.

Potential Distribution and Identification of Critical Areas for the Preservation and Recovery of Three Species of Cinchona L. (Rubiaceae) in Northeastern Peru

The genus Cinchona L. has important medicinal, cultural, and economic value and is the emblematic tree of Peru. The genus is mainly found in the cloud forests of the Andes. However, the expansion of agriculture and livestock farming in the department of Amazonas is degrading these ecosystems and has reduced the size of the genus’s populations. In this work, we model the potential distribution under current conditions of three Cinchona species (C. capuli L. Anderson, C. macrocalyx Pav. Ex DC., and C. pubescens Vahl.) to identify areas with a high likelihood of species presence and their key conservation and reforestation zones. We fitted a maximum entropy (MaxEnt) model using nineteen bioclimatic variables, three topographic variables, nine edaphic variables, and solar radiation. Under current conditions, the potential distribution of C. capuli covers 17.22% (7243.98 km2); C. macrocalyx, 29.11% (12,238.91 km2); and C. pubescens, 22.94% (9647.63 km2) of the study area, which was mostly located in central and southern Amazonas. Only 24.29% (25.51% of C. capuli, 21.02% of C. macrocalyx, and 26.35% of C. pubescens) of the potential distributions are within protected areas, while 10,987.22 km2 of the surface area of the department of Amazonas is degraded, of which 29.80% covers the area of probable occurrence of C. capuli, 38.72% of C. macrocalyx, and 34.82% of C. pubescens. Consequently, it is necessary to promote additional conservation strategies for Cinchona, including the establishment of new protected areas and the recovery of degraded habitats, in order to protect this species.

Cinchonine: A Versatile Pharmacological Agent Derived from Natural Cinchona Alkaloids.

Cinchonine is one of the Cinchona alkaloids that is commercially extracted from the Peruvian bark of Cinchona officinalis L. (Family: Rubiaceae). It is also obtained in much lower quantities from other species of Cinchona, such as Cinchona calisaya, Cinchona succirubra, and Cinchona pubescens, and in some other plants, such as Remijia peruviana. Cinchonine has been historically used as an anti-malarial agent. It also has a wide range of other biological properties, including anti-cancer, anti-obesity, anti-inflammatory, anti-parasitic, antimicrobial, anti-platelet aggregation, and anti-osteoclast differentiation. This review discusses the pharmacological activity of cinchonine under different experimental conditions, including in silico, in vitro, and in vivo. It also covers the compound's physicochemical properties, toxicological aspects, and pharmacokinetics. A comprehensive literature search was conducted on multiple online databases, such as PubMed, Scopus, and Google Scholar. The aim was to retrieve a wide range of review/research papers and bibliographic sources. The process involved applying exclusion and inclusion criteria to ensure the selection of relevant and high-quality papers. Cinchonine has numerous pharmacological properties, making it a promising compound for various therapeutic applications. It induces anti-cancer activity by activating caspase-3 and PARP-1, and triggers the endoplasmic reticulum stress response. It up-regulates GRP78 and promotes the phosphorylation of PERK and ETIF-2α. Cinchonine also inhibits osteoclastogenesis, inhibiting TAK1 activation and suppressing NFATc1 expression by regulating AP-1 and NF-κB. Its potential anti-inflammatory effects reduce the impact of high-fat diets, making it suitable for targeting obesity-related diseases. However, research on cinchonine is limited, and further studies are needed to fully understand its therapeutic potential. Further investigation is needed to ensure its safety and efficacy in clinical applications. Overall, this review article explains the pharmacological activity of cinchonine, its synthesis, and physicochemical properties, toxicological aspects, and pharmacokinetics.

Genetic profiles of three Cinchona species in Junghuhn Natural Reserve, Indonesia

Cinchona species were widely used as ancient medicines for different diseases because they contain the active component quinine and its derivatives. However, studies on the molecular aspects of cinchona, including its genetic diversity, have not been reported because most previous works focused on the administration of the antimalarial cinchona alkaloid. Quinine is also being tested as alternative compound for the treatment of Covid-19. The Junghuhn Natural Reserve in Indonesia contains three different types of cinchona plants, namely, Cinchona calisaya, Cinchona pubescens, and Cinchona sp. Given that the genetic diversity and kinship of these species have never been studied, collecting data on the cinchona gene pool has become imperative. This study analyzed the genetic diversity of the cinchona species in the Junghuhn Natural Reserve, Indonesia, by using eight RAPD markers, i.e., OPA-2, OPA-9, OPB-02, OPB-03, OPB-04, OPB-05, OPB-7, and OPJ-07, during 2020 at the University of Jenderal Soedirman, Purwokerto-Indonesia. Polymorphic band data were obtained. Then, phenogram analysis was conducted by using UPGMA and maximum parsimony with MEGA7. The RAPD profiles of Cinchona species (C. calisaya, C. pubescent, and Cinchona sp.) revealed polymorphism with different markers, i.e., OPA-2 (90%), OPB-2 (75%), OPB-5 (75%), OPB-3 (66.66%), OPB-4 (66.66%), OPB-7 (66.66%), OPJ-7 (66.66%), and OPA-9 (58.33%) sequentially with total polymorphism (70.62%). C. calisaya was identified as the most distinctive species. UPGMA yielded a coefficient of 0.200 and two distinctive groups: Group I, which comprised C. pubescens and Cinchona sp. with the p-distance value of 0.333, and Group II, which contained C. calisaya. Ixora sp. was treated as an outgroup plant. The topology of the dendrogram was consistent with that of the UPGMA dendrogram. Results may be used for the further exploration of the genetic diversity of cinchona species.

Role of medicinal plants in corona infection with reference to Cinchona species

Corona virus diseases 2019 (COVID-19) is a life threatening global health Scenario, WHO (World Health Organization) has declared as their diseases is pandemic and is a global issue. The severity of this diseases has caused highest death rates from December-2019 to October 2020 World wide Medicinal plants and plant based drugs play a major role in preventing the diseases and enhance the immune system. This article reviews diseases the major global issue pandemic corona virus diseases (COVID-19) and Medicinal plants used to treat and prevent the coronavirus with respect to Cinchona species which has the medicinal properties to control the disease. The genus Cinchona Linn (Rubiaceae) comprises about 40 species of evergreen shrubs or trees growing naturally in South America. Species of the genus are medicinally very important. Their bark yields a variety of useful alkaloids, of which the most important are quinine, quinidine and cinchonidine. Quinine is a very effective drug for the treatment of maleria, and quinidine for the treatment of heart disease. On account of the medicinal value of Cinchona, several species have been domesticated in India, and a few grown as plantation crops in the Nilgiris and Anamalai in South India. Some species are also found growing wild around the genus Cinchona Linn (Rubiaceae) comprises about 40 species of evergreen shrubs or trees.

Review: Just the Tonic: A Natural History of Tonic Water, by Kim Walker and Mark Nesbitt

The next time you sip your gin and tonic, spare a thought for Doña Francisca Henríques de Ribera, countess of Chinchón and wife of the viceroy of Peru. When the beautiful countess lay languishing and feverish on her deathbed sometime around 1630, she was given a dose of a local “fever bark” and, surprisingly, recovered. So thankful was she for this miraculous cure that, the story goes, she returned to Spain to dispense the bark to the suffering of Europe. It may all sound somewhat fanciful, but the story was enough for the Swedish botanist Linnaeus to name both the tree and the genus after the countess (although he managed to drop the first “h” in the process, so it became Cinchona). It is the bark of the cinchona tree, and the powerful antimalarial quinine compounds it contains, that is famously the bitter flavoring in tonic water. Of course this did not happen overnight; the history of the links between cinchona, quinine, malaria, tonic water, and gin are much more complex and more fascinating than one might suspect, as Just the Tonic shows.Like all the best books focusing on single foods or drinks, the fun is in the broader contextualization. Together, co-authors Kim Walker (student of the history of plant medicines) and Mark Nesbitt (curator of the Economic Botany Collection at the Royal Botanic Gardens, Kew, London) open up a series of different worlds to introduce us to the history of tonic water. They explore the nature of malaria and the slow voyage of discovery that led to the understanding of its transmission. We are also treated to a natural history of the tree itself, which, from the seventeenth century, was in great demand in Europe for treating fevers of all sorts. Indeed, when the Parisian pharmacist Auguste Delondre first set eyes on a specimen in the Peruvian Andes, he remarked: “That magnificent tree. For so long I had seen it in my dreams and now it was before me” (p.11). Long before the nature and causation of malaria were understood (early in the twentieth century) and long before the workings of quinine in blocking the actions of the malaria-causing parasite in the blood were appreciated (even now not perfectly understood), cinchona and its derivative quinine were being taken as both “preservative” and treatment for malaria.Just the Tonic brings together three strands to tell a single story, mixing well-informed historical narrative and quirky anecdote. While the first part of the book focuses on quinine and its use against malaria, the second explores the cultural history of the most popular medium for administering the drug; that is, via carbonated water. In the process, we are treated to a (very) brief history of medicinal mineral waters, the rise of “aerated” or soda waters from the late eighteenth century, and the proliferation of “restorative” and “medicinal” tonic beverages—some highly alcoholic, others directed at the temperance movement—in the nineteenth century. These drinks were promoted, variously, as preventives, cures, and convalescent remedies; as stimulants either to the appetite (aperitifs) or to the digestion (digestives); and, eventually, as medicinal “tonics” and refreshing drinks in tropical climes.The third and final part recounts the history of gin, in particular in its combination with tonic. This is perhaps better known, but the authors nonetheless manage to relate some curious occurrences along the way, such as the technologies used in procuring the necessary ice in the pre-refrigeration age. Throughout, the authors have aimed for a “magazine” style of presentation, with short articles and even shorter text-boxes inserted at regular intervals. If the overall impression is on the erratic side, this approach does have the virtue of allowing them to cover a wide range of topics. The asides are distracting but frequently fascinating (in a frustrating sort of way). Just as one is coming to grips with the wide array of cinchona species that nineteenth-century naturalists had to grapple with, one’s attention is drawn by a small text-box on the accidental invention of the color mauve (on page 46, if you are curious). In any case, the book is beautifully produced. It abounds with magnificent and sometimes surprising illustrations, all carefully chosen, coming from the unparalleled collections of Kew Gardens and the Wellcome Collection, both in London.

Asymmetric α-Chlorination of β-Keto Esters Using Hypervalent Iodine-Based Cl-Transfer Reagents in Combination with Cinchona Alkaloid Catalysts.

We herein report an unprecedented strategy for the asymmetric α‐chlorination of β‐keto esters with hypervalent iodine‐based Cl‐transfer reagents using simple Cinchona alkaloid catalysts. Our investigations support an α‐chlorination mechanism where the Cinchona species serves as a nucleophilic catalyst by reacting with the chlorinating agent to generate a chiral electrophilic Cl‐transfer reagent in situ. Using at least 20 mol‐% of the alkaloid catalyst allows for good yields and enantioselectivities for a variety of different β‐keto esters under operationally simple conditions.

Chemical characterization, antihyperlipidaemic and antihyperglycemic effects of Brazilian bitter quina species in mice consuming a high-refined carbohydrate diet

Abstract Quina is the popular name for species of Cinchona, native to Peru and whose barks produce quinine. Currently, quinine is also used as a bitter additive in tonic water and drinks. Cinchona species do not occur in Brazil, but other species are known as quina, due their bitter taste and use as digestive tonics. In this study, six species of Brazilian quina were chemically characterized and three of them evaluated as antihyperlipidaemic and antihyperglycemic agents. The chemical composition was determined by spectroscopy, HPLC-DAD and LC-MS. Plasma concentrations of glucose and cholesterol were strongly reduced in animals receiving extracts from Baccharis trimera and Strychnos pseudoquina. These effects were attributed to the presence of higher concentrations of flavonoids and organic acids. S. pseudoquina also promoted a significant reduction of triglyceride, as well as a better fat distribution. The cytotoxicity assay the R. ferruginea and S. pseudoqina species in LD50 are greater than 1000 μg/mL and a percent viability during the 100% assay. B. trimera has already been applied to DL50 with a very high dose of 4.92 μg/mL, presenting a low viability during the analysis and cytotoxic assimilation. The results of this study confirm the role of bitter quina in digestive metabolic disorders.

Morpho-anatomy of native species used as substitute of quina (Cinchona spp.) in Brazilian traditional medicine: Esenbeckia febrifuga

Esenbeckia febrifuga (A.St.-Hil.) A. Juss. ex Mart., Rutaceae, is known by several popular names including quina-do-mato. This name is a reference to the use of its bark as febrifuge and in the past was employed as a substitute of Cinchona sp. for treatment of malaria symptoms. This confusion may have been reinforced by the fact that the bark of these plants are similar in appearance and have a bitter taste. In view thereof this study presents the description morphological and anatomical and the histochemistry of the stem bark and contributes to the pharmacobotanical study of plant drugs identified as Brazilian quinas, in sequence to two others studies. Compared with the Cinchona species, the prismatic shape of calcium oxalate crystals and the fibers with adornate end walls proved to be the main characteristics for differentiation.

The Critical Role of Tilted Cinchona Surface Species for Enantioselective Hydrogenation

On chirally modified metal catalysts enantioselectivity is controlled by the molecular orientation of adsorbates at the chiral catalytic solid–liquid interface. To gain information on the surface coverage and to assess the enantioselecting ability of chiral modifiers depending on their molecular orientation, we employed an operando spectroscopic technique using attenuated total reflection IR and UV–vis spectroscopy. Our study reveals that the enantiodifferentiation of the cinchona chiral modifier cinchonine varies significantly depending on its adsorption mode. In contrast to the prevailing mechanistic models, which imply that the most stable surface species is responsible for enantiodifferentiation, our results show that less stable cinchona species with a tilted aromatic ring anchor provide significantly stronger enantioselective control. As a consequence, the so-called anchoring moiety of the chiral modifier exceeds the mere function of adsorptive anchoring and its molecular orientation has to be also ...

An Optimised Method for Routine Separation and Quantification of Major Alkaloids in Cortex Cinchona by HPLC Coupled with UV and Fluorescence Detection.

Authentication of herbal products to ensure efficacy and safety require efficient separation and quantification of constituents. Standard assays for Cinchona bark used for the treatment of malaria and production of quinine, either use only spectrophotometry to detect two pairs of diastereoisomers of quinine and cinchonine type alkaloids (European Pharmacopoeia, Ph.Eur.) or liquid chromatography primarily optimised for detection of the four major alkaloids. However, numerous minor alkaloids occur in Cinchona and related species and efficient separation including gradient elution is necessary in order to obtain the full pattern of constituents in bark samples. To develop an optimised HPLC method for separation and quantitative analysis of the four major alkaloids in Cinchona bark using UV detection. Dimethyl sulphoxide (DMSO) extracts of 50mg of pulverised barks were prepared using ultrasonication. The chromatographic separation was performed on an XB-C18 column packed with 2.6μm particles. Gradient elution using an ammonium formate buffer and methanol as organic modifier over 26min was based on non-chiral separation of the diastereoisomers and the high solvent selectivity of methanol. Post column UV detection was performed at 250nm and 330nm. Fluorescence detection was performed using 330nm for excitation and 420nm for emission. The optimised HPLC method facilitates efficient separation and quantification of the four major alkaloids in 26min with a limit of quantification of 5μg/g from 50mg bark sample. The optimised HPLC method offers a simple and efficient quantification of the four major alkaloids. Copyright © 2017 John Wiley & Sons, Ltd.

Cinchona anderssonii (Rubiaceae), a new overlooked species from Bolivia

Cinchona anderssonii, a new species from the Yungas forests of the Andes in Bolivia, is described and illustrated. It is unique in Cinchona by having the combination of elliptic leaf blades glossy above, distinct circular pit domatia at secondary vein axils, basipetally dehiscent capsules, and relatively large seeds (8–11 mm long). A taxonomic key for the identification of the Cinchona species occurring in Bolivia is presented.

Morpho-anatomy and chemical profile of native species used as substitute of quina (Cinchona spp.) in Brazilian traditional medicine. Part II: Remijia ferruginea

This research is part of a larger study of the Brazilian species that are commonly referred to as “quinas” and used as substitute of Cinchona species. In this study, we have performed the botanical characterization of the stem bark of Remijia ferruginea (A. St.-Hil.) DC., Rubiaceae, by morphological and anatomical description, and the analysis of its chemical profile. Stem bark is thin and has the color and the texture of its external and internal surfaces as diagnostic features. Types and sizes of sclerified cells in the cortical parenchyma and in the secondary phloem are important features for analysis of the transversal sections and in the macerate. Alkaloids, flavonoids and chlorogenic acid were detected in the chemical analysis for TLC. These standard references can be used in the quality control of the bark of quinas.

Micrografting technique in cinchona (Cinchona ledgeriana Moens) plants propagation

In Indonesia has been found 11 cinchona species but only two species recognized as an economically important Cinchona succirubra known as resistant plant to root disease while Cinchona ledgeriana quinine high content. To put together those two characters from mostly through grafting it took twelve months. Micrografting is one of the propagation techniques through tissue culture. Micrografting has already been used in wide spread for plants propagation either only for research or as mass product. Hopefully, the use of micrografting to obtain cinchona propagation would be short more or less 10 months and provide plants as mass production economically. The result showed that micro grafting at V shape could be used as the propagation method on cinchona species besides bud multiplication through tissue culture. MS medium is the best medium for cinchona micrografting. If there is no IBA on rooting media, there is no root formation from the plants. The increasing of IBA from 1 up to 4 mg/l in media, will increase also the number of rooting plants.different plant material as scion and stock and different concentrarions (0,1,2,3,4 mg/l) of IBA gives the significantly different respons on rooting formation. The increasing of IBA on media will increase the number of rooting plants also. The highest rooting formation are found on medium with 3 dan 4 mg/L IBA. The combination between C. ledgeriana-C. succirubra, C. ledgeriana-C.ledgeriana, C. succrirubra-C.succirubra gives significantly difference on the growth dan development of root. The use of C. ledgeriana as a root stock doesn’t showed good rooting formation. The combination between CSA/QRC205 gives the highest number of leaves result compare wth others combination on as much as 9,8. The first stage of acclimatization on culture room with temperature 25-270C and followed by acclimatization on plastics house covered with paranet 70%. In general in vitro planlet cinchona from micrografting growing well. By the end of observation (8 weeks) growing percentage reach 90%. Â

Morpho-anatomy and chemical profi le of native species used as substitutes of quina (Cinchona spp.) in Brazilian traditional medicine. Part I: Polyouratea hexasperma

This research is part of a larger study of the Brazilian species that are commonly referred to as quinas and are usually used as substitute of Cinchona species. The purpose of the present study was the botanical characterization of the whole and powdered stem bark of Polyouratea hexasperma (A. St.-Hil.) Tiegh., Ochnaceae, by morphological and anatomical description, and the analysis of its chemical profile. The external texture of the bark, the whitened pit in the inner bark and the presence of cristarque cells, as well as the shape and arrangement of other lignified cells, are the most important macroscopic and microscopic features for the characterization of the bark. Chlorogenic and cafeic acids were detected in the chemical analysis and can also be used in the identification of the bark.

Cryptolepine and development of new antimalarial agents

Natural product-derived drugs exemplified by quinine, isolated from South American Cinchona species and artemisinin discovered in China are of immense importance for the treatment of malaria. Although malaria parasites resistant to artemisinin have not yet been found in malaria patients, the need for new antimalarial agents remains. The burden of malaria is heaviest in Africa where over a million children die of the disease each year, but although many medicinal plants are used in African traditional medicines for the treatment of malaria, none has yet yielded and effective antimalarial compound. Cryptolepis sanguinolenta (Periplocaceae), is a West African climbing shrub used traditionally for the treatment of malaria. Cryptolepine, an indoloquinoline alkaloid is the major constituent of the roots of C. sanguinolenta and has potent activity against malaria parasites in vitro, but it is cytotoxic on account of its abilities to inhibit topoisomerase II and to intercalate into DNA and it is also toxic to mice in vivo. However, the antimalarial mode of action of cryptolepine appears to involve a quinine-like mechanism (inhibition of ?-haematin formation) that is independent of interactions with DNA. This opens up the possibility that it may be feasible to prepare analogues of cryptolepine that do not interact with DNA (and hence may be less cytotoxic) but that retain or have enhanced antiplasmodial activities. Using various synthetic routes, a number of substituted cryptolepine analogues have been made and evaluated for their potential as leads to new antimalarial agents. Compounds were assessed for in-vitro activities against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum and for cytotoxic activities. Some compounds have been assessed for their abilities to interact with DNA and a number of compounds has also been assessed for antimalarial activity against P. berghei in mice. Several cryptolepine analogues were found to have potent antiplasmodial activities (IC50 < 0.1 µM) against chloroquine-resistant P. falciparum (IC50 for chloroquine = 0.44 µM), but they are generally of similar cytotoxicity to cryptolepine. However, while cryptolepine is toxic to mice, a number of analogues have been shown to have promising antimalarial activities in the mouse-malaria model with no apparent toxicity. In view of this, derivatives of cryptolepine appear to be worthy of further investigation as potential antimalarial agents. In this lecture, the current status of antimalarial cryptolepine research will be reviewed and the potential of cryptolepine as a lead to new antimalarial agents will be discussed.

Empire and Alternatives: Swietenia febrifuga and the Cinchona Substitutes

Empire and Alternatives: <i>Swietenia febrifuga</i> and the Cinchona Substitutes

Tree invasion in managed tropical forests facilitates endemic species

AbstractAim To determine whether different abundances of introduced species of Cinchona (Rubiaceae) affect species composition and facilitate species richness in managed tropical forests, to test whether any facilitative effects on understorey species depend on forest type, and to investigate whether facilitative effects can be attributed to the ‘substitutive facilitation model’.Location Makawao Forest Reserve on Maui, Hawai’i, USA.Methods Cinchona species (Cinchona pubescens and Cinchona calisaya) were mapped within various forest types. In three forest types (ageing Eucalyptus and Pinus plantations, and near‐natural Acacia koa forests), we analysed environmental parameters (e.g. canopy cover, litter cover, pH value and soil depth) and the species composition of Cinchona‐invaded and non‐invaded plots; data were compared based on Cinchona cover and forest types. Habitat modelling for several endemic species and tree ferns was carried out to test whether Cinchona cover is an important variable for the probability of occurrence of these endemics.Results Cinchona species have naturalized mainly in Eucalyptus and Pinus plantations and Acacia koa forests and here add an additional shrub layer. In contrast to other studies, we revealed facilitative effects of Cinchona on native species within all forest types. Species richness is about 20% higher in invaded plots than in non‐invaded plots, and these show a nearly 50% higher proportion of endemic species, including tree ferns. The proportion of endemics even increases with increasing Cinchona cover. For several endemics, Cinchona is found to be an important variable for the probability of occurrence, and the removal of Cinchona cover as an explanatory variable lowers the model fit. In addition to Cinchona, variables delineating vegetation structure and light availability have a strong effect on the model fit.Main conclusions In the structurally simplified Hawaiian forests studied, Cinchona facilitated endemic species in accordance with the ‘substitutive facilitation model’. This contrasts with the results of an earlier study in the naturally treeless Galápagos highlands, which revealed a sharp decrease in the abundance of endemics under Cinchona canopy. These results illustrate that, through the same structural change (addition of a vegetation layer), an invasive species may exert divergent effects across different ecosystem types. The facilitation of endemic understorey species by invasive tree species in managed forests leads to a dilemma in conservation but also to new perspectives for ecosystem restoration.

State of the art of the production of the antimalarial compound artemisinin in plants.

For more than three centuries we have relied on the extracts of the bark of Cinchona species to treat malaria. Now, it seems we may be changing to the leaves of a Chinese weed, Artemisia annua, and its active compound artemisinin. Artemisinin-derived drugs have been proved particularly effective treatments for severe malaria, even for multidrug-resistant malaria. However, this promising antimalarial compound remains expensive and is hardly available on a global scale. Therefore, many research groups have directed their investigations toward the enhancement of artemisinin production in A. annua cell cultures or whole plants in order to overproduce artemisinin or one of its precursors. This article provides a brief review of the state of art of the different aspects in A. annua research.

A Method for the Quantitative Determination of Anthraquinones and Alkaloids in Cell and Tissue Cultures ofCinchonaSp.

A procedure is described for the extraction of both anthraquinones and alkaloids from tissue culture material of CINCHONA species. Using this extraction method, it is possible to quantitatively determine the two groups of secondary metabolites produced in CINCHONA tissue cultures.