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Sugar Control of Artemisinin ProductionWANG, YI 29 April 2006 (has links)
The role of sugars as regulatory signals has mainly focused on their effects on plant growth, development, gene expression, and metabolism. Little, however, is known about their role in controlling secondary metabolism. Previous work in our lab showed that sugars affect the production of the sesquiterpene antimalarial drug, artemisinin, in hairy roots of Artemisia annua. In this study, sugars alone or in combination with their analogues were used to investigate if sugars control artemisinin production in Artemisia annua seedlings. Compared to sucrose, a 200% increase in artemisinin by glucose was observed. When the glucose analog, 3-O-methylglucose, which is not phosphorylated effectively by hexokinase, was added with glucose, artemisinin production was dramatically decreased but hexokinase activity was significantly increased compared to glucose. In contrast, neither mannose, which can be phosphorylated by hexokinase, nor mannitol, which can not be transported into cells had any significant effect on artemisinin yield. When different ratios of fructose to glucose were added to seedlings, artemisinin yield was directly proportional to glucose concentration. Although addition of sucrose with glucose gave inconclusive results, sucrose analogues decreased artemisinin production compared to sucrose. These results suggested that both monosaccharide and disaccharide sugars may be acting as signal molecules thereby affecting the downstream production of artemisinin. Taken together, these experiments showed that sugars clearly affect terpenoid production, but that the mechanism of their effects appears to be complex.
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Roots and hormones: synergistic control of artemisinin production in Artemisia annua L. shootsNguyen, Khanh Van T 06 December 2011 (has links)
"Artemisinin is a potent antimalarial drug produced in the plant Artemisia annua. Earlier reports suggested that the roots play a key role in artemisinin production; however, it was not clear if other factors actually affected production instead of roots. Here the role of roots and two phytohormones, NAA and BAP, were studied to determine what role each plays in artemisinin production in the plant. Rooted Artemisia annua shoots produced significantly more artemisinin, arteannuin B, and deoxyartemisinin, the end products in the pathway, than unrooted shoots. Although roots do not seem to affect the levels of precursors, artemisinic acid and dihydroartemisinic acid, or regulate the transcription of the genes in the pathway, rooted plants developed larger trichome sacs suggesting that the accumulation of end products is linked to the expansion of the trichome sac. Unrooted shoots are grown in shooting medium containing higher amount of MS salts, vitamins, sucrose and two potent phytohormones, NAA and BAP. Rooted shoots grown in rooting medium containing either one or both of these hormones showed that NAA increased production of arteannuin B in the young leaves and artemisinin in the mature leaves; in mature leaves, however, arteannuin B was inhibited by NAA. BAP induced production of both the precursors and the end products, except for artemisinin, in the young and/or mature leaves. When rooted shoots with their roots removed were grown in rooting medium containing either one of these hormones, artemisinin was significantly less in cultures grown with BAP while there were no differences in metabolite levels in cultures grown with NAA. Although the importance of roots on the artemisinin biosynthetic pathway cannot be concluded, these results help improve our understanding of artemisinin biosynthesis as may prove useful for improving artemisinin production in field-grown crops."
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Cicatrização da úlcera por pressão experimental com fumaça de moxa palito de Artemisia vulgaris em comundongosLima, Ricardo de Oliveira January 2013 (has links)
LIMA, Ricardo de Oliveira. Cicatrização da úlcera por pressão experimental com fumaça de moxa palito de Artemisia vulgaris em comundongos. 2013. 150 f. Dissertação (Mestrado em Farmacologia) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2013. / Submitted by denise santos (denise.santos@ufc.br) on 2014-03-21T10:57:18Z
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Previous issue date: 2013 / Pressure ulcer (PU) is a common injury among elderly and subjects with impaired physical mobility. It affects the quality of life of individuals and generates considerable costs, since it is becoming a worldwide growing problem due to the aging of the population. Cycles of ischemia and reperfusion from pressure have been identified as primary causal factor but other factors influence the intensity of damage. Currently, there is no effective and inexpensive method to treat this condition. For this reason, we aimed to check whether the traditional indication of smoke from Artemisia vulgaris (SAV) really contributes to the wound healing process of the PU. This work was approved by Ethics Committee (89/2011). It was used a non-invasive model of PU in mice which consists of 4 cycles of ischemia and reperfusion by the placement of two magnets on the dorsal skin surface of mice. Five experimental groups were tested: negative control, with ulcer and without treatment; positive control, with ulcer and treated with hydrogel and transparent film; treated group 1, with ulcer and topical SAV, treated group 2, with ulcer and topical SAV and transparent film, and a group without ulcer and without treatment. The analysis was conducted on days 5, 7, 14 and 21 after ulcer induction. Macroscopic parameters of healing were assessed through the EWAT (Experimental Wound Assessment Tool). Wound area, percentage of contraction, histopathological analysis, collagen layer thickness and collagen density in the dermis, counting of fibroblasts and fibrocytes, measurement of epidermis thickness were also assessed. Evaluation of the immunostaining for iNOS and nitrotyrosine and malondialdehyde assay (MDA) was performed to investigate oxidative stress. Toxicological tests were conducted in treated animals and SAV showed no toxic effect. In all the results SAV+film treatment was better than SAV. Results: Macroscopic EWAT and inflammatory scores showed significant differences between SAV+film treated group and control group (p<0,01). Wound contraction area was enhanced in SAV+film group by 99,62% (vs 84,65%, control) as well as fibroblast count (112,7 ± 7,9 vs 80,0 ± 6,4; control, p<0,01) and collagen density (33,9% ± 6,6 vs 20,9% ± 8,6; control, p<0,01). Epidermal width was increased by SAV+film (113,2 ± 18,1 vs 52,1 ± 8,9; control p<0.01) and also the blood vessel counting in the conjunctive tissue (142,3 ± 15,1 vs 68,5 ± 8,6; control, p<0.01). The counting of iNOS and nitrotyrosine immunostained cells showed a reduction by SAV+film (601,5 ± 94,0 vs 2005,0 ± 95,7; control, iNOS and 666,0 ± 142,4 vs 1877,2 ± 133,8; control, nitrotyrosine, p<0.01). MDA assay showed also a reduction by SAV+film treatment (0,08 ± 0,03 vs 0,3 ± 0,05; control, p<0.05). In conclusion, SAV topical application promoted wound healing by anti-oxidant properties and by modulating the inflammatory process. The effect of SAV was enhanced when the wound area was covered by the transparent film after smoke application. In addition, this method showed no toxic effect and may be an effective and low cost alternative for PU healing treatment. / Úlcera por pressão (UP) é uma lesão comum entre idosos e indivíduos com mobilidade física prejudicada. Ela afeta a qualidade de vida dos indivíduos e gera custos consideráveis, uma vez que está se tornando um problema mundial crescente, devido ao envelhecimento da população. Ciclos de isquemia e reperfusão têm sido identificados como fatores causais primários, mas existem outros fatores que influenciam a intensidade dos danos. Atualmente, não existe um método eficaz e de baixo custo para tratar esta condição. O uso clínico da fumaça de Artemisia vulgaris (FAV) para o tratamento de lesões na pele de diversas origens está descrito na literatura. Entretanto é pouco documentado e atualmente nada foi descrito em modelos experimentais de ulcera por pressão a respeito da sua atividade cicatrizante, bem como o seu efeito tóxico. Dessa forma objetivou-se investigar o perfil toxicológico e o efeito cicatrizante da aplicação tópica da fumaça de Artemisia vulgaris em modelo de úlcera por pressão em camundongos. Este trabalho foi aprovado pelo Comitê de Ética (89/2011). Foi utilizado um modelo não-invasivo de UP em camundongos Swiss machos, que consiste em 4 ciclos de isquemia e reperfusão através da colocação de dois ímãs na superfície da pele dorsal. Cinco grupos experimentais foram testados: (1): com úlcera e sem tratamento, (2): com úlcera e FAV tópico, (3): com úlcera, FAV tópica e filme de poliuretano, (4): com úlcera e tratado com hidrogel e filme de poliuretano e (5) sem úlcera, e sem tratamento. A análise foi realizada nos dias 5, 7, 14 e 21 após a indução da úlcera. Foram avaliados parâmetros macroscópicos de cicatrização através da escala EWAT (Experimental Wound Assessment Tool – Instrumento de avaliação de ferida experimental), área da ferida e porcentagem de contração. Nos parâmetros microscópicos foram avaliados: a análise histopatológica, a espessura da camada de colágeno e densidade de colágeno na derme, a contagem de fibroblastos e fibrócitos e a medição da espessura da epiderme. Avaliação da imunomarcação para NOSi e nitrotirosina e ensaio de malondialdeído (MDA) foi realizado para investigar o stress oxidativo. Testes toxicológicos com parâmetros hematológicos, bioquímicos, histopatológicos e comportamentais foram realizados em animais tratados com FAV. Resultados: a FAV não mostrou toxicidade nos parâmetros avaliados. Em todos os resultados a FAV + filme transparente foi melhor do que a FAV. EWAT macroscópica e escores inflamatórios mostraram diferenças significativas entre o grupo tratado, FAV + filme de poliuretano e grupo controle (p <0,01). Área contração da ferida foi aumentada em no grupo FAV grupo + filme de poliuretano, por 99,62% (84,65% vs, controle), bem como a contagem de fibroblastos (112,7 ± 7,9 vs 80,0 ± 6,4; controle, p < 0,01) e densidade de colágeno (33,9% ± 6,6 vs 20,9 ± 8,6%, controle, p <0,01). FAV + filme de poliuretano aumentou a espessura da epiderme (113,2 ± 18,1 vs 52,1 ± 8,9, controle p <0,01) e também a contagem do número de vasos sanguíneo no tecido conjuntivo (142,3 ± 15,1 vs 68, 5 ± 8,6; controle, p <0,01). O número de células marcadas para NOSi e nitrotirosina, foi reduzido no grupo FAV + filme de poliuretano (601,5 ± 94,0 vs 95,7 ± 2005,0, controle, NOSi e 666,0 ± 142,4 vs 1877,2 ± 133, 8; controle, nitrotirosina, p <0,01). O MDA também foi reduzido pelo tratamento com FAV + filme de poliuretano (0,08 ± 0,03 vs 0,3 ± 0,05; controle, p <0,05). Concluímos que a aplicação tópica da FAV não produziu efeito tóxico e acelerou a cicatrização de feridas possivelmente por propriedades antioxidantes. O uso do filme de poliuretano intensificou a ação da FAV.
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Cultivo in vitro de Artemisia annua L. para a produção de artemisininaChang, Claudia Isabel Paola Hinojosa 05 March 1996 (has links)
Orientador: Simone L. K. Shepherd / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-21T11:36:24Z (GMT). No. of bitstreams: 1
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Previous issue date: 1996 / Resumo: A malária, um dos maiores problemas de saúde pública dos países tropicais, vem sendo combatida através de medicamentos sintéticos como a cloroquina e derivados, os quais apresentam sérios efeitos colaterais e cuja eficácia é afetada principalmente pela resistência do agente causador da malária a estes medicamentos. Um extrato vegetal de Artemisia annua, contendo artemisinina vem sendo utilizado à milhares de anos na China e tem-se mostrado eficaz no combate às febres, entre elas a malária. A influência da concentração dos nutrientes dos meios padrão Murashige & Skoog (1962), Gamborg et al (1968)e White (1943), adicionados de fitoreguladores (GA3 e AIA), na produção de artemisinina e do seu precursor, o ácido artemisininico foi observada através dos estudos de cultivo in vitro de Artemisia annua L. Os cultivos in vitro das plântulas foram realizados em períodos de 14 e 28 dias. Os experimentos mostraram que dentre os meios padrões utilizados o meio White (com nutrientes em menor concentração) promoveu um maior efeito tanto no crescimento das plântulas, como na produção de artemisinina. Para otimizar a produção in vitro de artemisinina e do ácido artemisinínico, 80 meio de White foi adicionado o retardante de crescimento (CCC) e foram reduzidos os níveis de fosfato e nitrato das concentrações originais do meio constatando-se que não afetaram significativamente o teor de artemisinina. Já a diminuição pela metade da concentração original de nitrato do meio White aumentou significativamente a produção de ácido artemisininico na parte aérea. A adição do retardante CCC (com o ótimo da concentração de 150 mg/l) no meio padrão de White aumentou significativamente a produção do ácido artemisininico, notadamente na parte aérea. Assim, o estudo da composição nutricional do cultivo in vitro permite uma otimização da produção de artemisinina e do respectivo precursor, visando a obtenção de um medicamento antimalarico, oferecendo pois, uma importante perspectiva para a indústria farmacêutica já que a sintese quimica de artemisinina até hoje, tem-se mostrado técnica e economicamente inviável / Abstract: Malaria, one of tbe major public health poblems in tropical countries, has been counteracted by syntbetic drogs such as chloroquine and their derivatives, presenting serious side effects. In addition their efficacy is affected mainly by the resistance of the malaria causing agent to these drugs. A plant extract from Artemisia annua, containing artemisinin, has been used for millenium in China, showing great efficacy against fevers including malaria. The influence of the nutrient concentrations in the standatd basal media of Murashige & Skoog (1962), Gamborg et al (1968) and White (1943), supplemented with growth regulators GA3 and IAA an the production of artemisinin and its precursor artemisinic acid, was observed using an in vitro culture of Artemisia annua L. The experiments showed that of the different media tested, White's medium (with lower nutrieot concentrations) better enhanced the growth of seedlings and artemisinin production. In order to optimize the in vitro poduction of artemisinin and artemisinic acid, White's medium was supplemented with a growth retardant (CCC) and the phosphate and nitrate levels reduced. it being shown that this did not affect the artemisinin content significantly. A fifty percent reduction in the initial nitrate content of White's medium significantly increased the artemisinic acid productian in the serial part. The addition of CCC (optimal concentration of 150 mg/l) to White's basal medium significantly increased artemisinic acid productian, especially in the serial part.
Thus the study of the nutritional composition of an in vitro culture allowed optimization of the production of artemisinin and its precursor, with the objetive of obtaining an antimalarial drug, offering a valuable perspective for the pharmaceutical industry, since nowadays the chemical synthesis of artemisinin is technically and economically inviable / Mestrado / Mestre em Ciências
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The antimicrobial activity and phytochemistry of african wormwood ( artemisia )Gwebu, Lehlohonolo, Tebogo 13 June 2003 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Science In Medicine ( Pharmaceutical Affairs ) / Artemisia afra Jacq. wild also known as African wormwood, " umhlonyane" ( Xhosa and Zulu ) "lengana" ( Sotho And Tswana ) and "wildeals" ( Afrikaans 0 is an aromatic shrub belonging to the Asteraceace. It is widespread in South Africa extending from the mountainous regions of South Western cape, along the eastern coast to the Northern Province ( van Wyk et. al;1997 ) Due to the popular use of A. afra. The aerial part of sixteen samples from four natural populations were hydrodistilled and the essential oil analysed by GC_MS and tested for antimicrobial activity on anumber of bacteria and fungi. / IT2018
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Transcriptome based gene discovery in Artemisia annua L.January 2009 (has links)
Qi, Yan. / Thesis submitted in: December 2008. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 63-79). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.III / ABSTRACT --- p.IV / TABLE OF CONTENTS --- p.VII / LIST OF ABBREVIATIONS --- p.XI / Chapter CHAPTER 1. --- LITERATURE REVIEW --- p.1 / Chapter 1.1 --- the Plant of Artemisia annua L --- p.1 / Chapter 1.2 --- The disease of malaria --- p.3 / Chapter 1.2.1 --- The life cycle of Plasmodium parasites --- p.4 / Chapter 1.2.2 --- The Artemisinin-based combination therapies (ACTs) for the treatment of malaria --- p.5 / Chapter 1.3 --- Artemisinin --- p.8 / Chapter 1.3.1 --- The content and distribution of artemisinin --- p.8 / Chapter 1.3.2 --- The mechanism of artemisinin action --- p.9 / Chapter 1.3.2.1 --- The proposed non-specific mechanisms of action --- p.10 / Chapter 1.3.2.2 --- The proposed parasite-specific mechanisms of action --- p.11 / Chapter 1.3.3 --- The biosynthesis of artemisnin in vivo --- p.12 / Chapter 1.3.4 --- The biosynthesis of artemisinin in vitro --- p.16 / Chapter 1.4 --- Trichomes --- p.18 / Chapter 1.4.1 --- Non-glandular trichomes --- p.19 / Chapter 1.4.2 --- Glandular trichome --- p.20 / Chapter 1.4.3 --- Trichomes of Artemisia annua L --- p.21 / Chapter 1.5 --- DNA Sequencing Methods --- p.24 / Chapter 1.5.1 --- The basic principle of pyrosequencing --- p.25 / Chapter 1.5.2 --- 454 pyrosequencing and its application --- p.27 / Chapter CHAPTER 2. --- MATERIALS AND METHODS --- p.32 / Chapter 2.1 --- Chemicals --- p.32 / Chapter 2.2 --- Plant materials --- p.32 / Chapter 2.3 --- Preparation of the cDNA sample for 454 sequencing --- p.33 / Chapter 2.3.1 --- Scanning electron microscopy --- p.33 / Chapter 2.3.2 --- Isolation of glandular trichomes --- p.34 / Chapter 2.3.3 --- cDNA synthesis and normalization --- p.34 / Chapter 2.4 --- 454-EST SEQUENCING AND PROCESSING --- p.36 / Chapter 2.5 --- Analysis of 454 sequencing data --- p.37 / Chapter 2.6 --- Establishment of regeneration system of A. annua L --- p.37 / Chapter 2.6.1 --- Shoots induction from leaf discs --- p.37 / Chapter 2.6.2 --- The sensitivity of the explants to Kanamycin --- p.38 / Chapter 2.6.3 --- Rooting of the regenerated seedlings --- p.38 / Chapter CHAPTER 3. --- RESULTS AND DISCUSSION --- p.40 / Chapter 3.1 --- Glandular trichome isolation and cDNA preparation --- p.40 / Chapter 3.1.1 --- The distribution of glandular trichomes on A. annua --- p.40 / Chapter 3.1.2 --- The isolation of glandular trichomes --- p.42 / Chapter 3.1.3 --- The preparation of ds cDNA for 454 sequencing --- p.43 / Chapter 3.2 --- Pre-process of 454 pyrosequencing data --- p.44 / Chapter 3.3 --- Functional annotation of the 454-EST data --- p.47 / Chapter 3.4 --- Comparison of two sequencing runs --- p.49 / Chapter 3.5 --- Analysis of the 454 ESTs involved in secondary metabolisms --- p.50 / Chapter 3.6 --- Selection of the candidate genes --- p.55 / Chapter 3.7 --- Establishment of regeneration system of A. annua L --- p.57 / Chapter 3.7.1 --- Shoots induction from leaf discs --- p.57 / Chapter 3.7.2 --- Roots induction from shoots --- p.57 / Chapter 3.7.3 --- Sensitivity of A. annua to Kan --- p.59 / Chapter CHAPTER 4. --- CONCLUSION --- p.61 / REFERENCES --- p.63
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The effect of scarification, temperature and light conditions on seed germination of Artemisia afra jacq. Ex willd.Letsoalo, Mmakoma Mendy January 2022 (has links)
Thesis (M.A. Agricultural Management (Plant Production)) -- University of Limpopo, 2022 / Artemisia afra Jacq. ex Willd is a common medicinal plant in Africa belonging to the
Asteraceae plant family. It has been used for decades as a treatment for cold related
illnesses and a variety of other ailments such as asthma, malaria and kidney disorders.
As such this has led to its high demand and it is faced with threats of overharvesting. As
the plant is naturally occurring and not widely cultivated, it’s seed biology and germination
properties are not documented. The optimum requirements (temperature and
photoperiod) for seed germination as well as the effects of Moringa based biostimulant
and different scarification methods were investigated on A. afra seeds in this study. The
seeds were exposed to different scarification methods including physical scarification
(rubbing using sandpaper), hot water soaking, cold water soaking, acid treatment (H2SO4)
and fermentation (using effective microorganisms) while the untreated seeds served as
the control under all conditions.
Moringa based biostimulant was also used as a seed priming agent at 0, 0.5, 1 and 3%
levels. The seeds were then placed under a variety of photoperiods including constant
light, alternating light (16/8 hours) and continuous darkness at different temperatures
(15°C, 25°C and 35°C). Germination percentages and mean germination time (MGT)
were calculated from the results and Statistix 10.0 software was used at the probability
level of 5%, to compare the mean values. It was observed that under the different
temperatures without any other treatments, the highest germination rate (70%) was
achieved at a 25°C. No germination (0%) was obtained at both 15°C and 35°C in all the
experiments including scarification methods and photoperiods.
Under the scarification treatments, soaking in hot and cold water scarification improved
germination with final germination of 70%, compared to the other scarification methods
(Physical at 20%, acid treatment at 20% and control at 10%). There was no germination
observed (0%) for the fermented seeds in all the experiments. On the photoperiod
treatments, the highest germination percentage of 70% was observed under alternating
light condition. However, when mean germination time was calculated, continuous
xiv
darkness resulted in shortest MGT of 11 days compared to 13 days for both alternating
light and for continuous light in this set of experiment. Seed priming with Moringa based
biostimulant under alternating light conditions and at 25°C resulted in improved MGT.
Under the investigated treatments, the use of 3% biostimulant exerted the highest
improvement on germination with germination percentage of 62% and the shortest MGT
of 7 days compared to the other treatments.
Generally the final germination (%) and time of A. afra seeds were affected by
scarification, temperature, light and priming using Moringa based biostimulant. The
information generated from this study is important because it will contribute in bridging
the scientific gap on the information that has never been documented on optimum
requirements for effective propagation of A. afra through seeds. As such this information
will be useful for small scale farmers and medicinal plant growers who are willing to
recover the lost populations of A. afra through seed propagation thus improving their supply and income / National Research Foundation (NRF)
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Synthesis, cytotoxicity and proteomics studies of artemisinin derivativesLiu, Yungen, 劉運根 January 2007 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
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The Effects of Phytohormones on Growth and Artemisinin Production in Hairy Root Cultures of Artemisia Annua L.McCoy, Mark Christopher 29 May 2003 (has links)
"The in vitro addition of plant growth regulators (i.e. phytohormones) to Agrobacterium transformed hairy root cultures affects morphological and biochemical changes, resulting in altered growth and secondary metabolite accumulation rates in root tissues. Significant increases in both growth and secondary product accumulation have been observed, upon incubation with phytohormones, in some species. Consequently, the use of phytohormones in vitro has received increasing attention as a potential means for increasing those plant secondary products notoriously produced in small quantities. However, currently little is known about the specific effects of phytohormones on growth and secondary metabolism. The Chinese herb Artemisia annua L. produces artemisinin, an effective antimalarial therapeutic. Efforts to increase the amount of artemisinin via chemical synthesis or field-grown crops have met with huge costs and disappointingly low yields, respectively. Agrobacterium transformed hairy root cultures of A. annua (Clone YUT16) produce artemisinin and undergo rapid growth compared to non-transformed, making them a good model system to study secondary metabolite production. Demonstrated herein is the first definitive evidence, by any hairy root species, of a favorable response to exogenous combinatorial hormone application as well as the development of a two-stage culture system alluding to optimal growth and artemisinin production conditions in A. annua hairy roots. Furthermore, analysis of artemisinin and biomass accumulation in A. annua hairy roots in the presence of phytohormones has revealed effective individual as well as combinatorial phytohormone concentrations suitable for increasing single and bulk root growth, and artemisinin production. The effectiveness of an optimal phytohormone combination, with respect to time of addition, its relationship to inoculum size, and its combination with the provision of fresh nutrients and or mechanical stress to the roots is also described resulting in artemisinin yields of up to 0.8 ìg/g F.W. Although the findings contained herein are not yet optimized they do, however, argue for the potential usefulness of a two-stage production scheme using phytohormones to increase plant secondary metabolite production in vitro."
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Recent developments in research on terrestrial plants used for the treatment of malaria.Wright, Colin W. January 2010 (has links)
no / New antimalarial drugs are urgently needed to combat emerging multidrug resistant strains of malaria
parasites. This Highlight focuses on plant-derived natural products that are of interest as potential leads
towards new antimalarial drugs including synthetic analogues of natural compounds, with the
exception of artemisinin derivatives, which are not included due to limited space. Since effective
antimalarial treatment is often unavailable or unaffordable to many of those who need it, there is
increasing interest in the development of locally produced herbal medicines; recent progress in this area
will also be reviewed in this Highlight.
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