Cultivation and genetics of Artemisia annua L. for increased production of the antimalarial artemisinin

Malaria has been treated for over 350 years with quinine and quinine-derived drugs. However, in several areas of the world, some strains of the malarial parasite Plasmodium falciparum have developed resistance against these drugs. Recently, the World Health Organization (WHO) recommended the use of artemisinin-combination treatments (ACT) as the first-line treatment for multidrug-resistant falciparum malaria. The WHO estimates that current supplies of artemisinin are sufficient for only 30 million ACT, and is foreseeing the need for 130-220 million ACT in 2005 (WHO, 2004). Current research on the production of synthetic artemisinin-like compounds by the Roll Back Malaria project, pharmaceutical companies and academia resulted in a promising synthetic artemisinin-like compound (OZ277) which is currently undergoing phase I clinical trials. In about 5 years this drug is expected to be approved and made available to the public, however, meeting current global demands for ACT depends on the immediate availability of affordable artemisinin-derived drugs. This will involve expansion of the area under cultivation of Artemisia annua and improved methods of cultivation and processing of raw material, associated with more efficient methods for extraction and purification of artemisinin from plant material. This review addresses the agricultural, environmental and genetic aspects that may be useful in the successful large-scale cultivation of A. annua and for producing the antimalarial artemisinin in areas where it is urgently needed today. It also includes geographic aspects (latitude and altitude), which will help make decisions about crop establishment in tropical countries, and includes a list of Good Agricultural and Collection Practices for A. annu

Atividade antimicrobiana de extratos hidroalcólicos de espécies da coleção de plantas medicinais CPQBA/UNICAMP

Extratos obtidos a partir de 45 espécies da Coleção de Germoplasmas do CPQBA foram estudados quanto à atividade antimicrobiana. As espécies que apresentaram forte inibição (Concentração Mínima Inibitória até 0,5 mg/mL) para os respectivos microrganismos foram: Achillea millefolium (0,5), Mikania laevigata (0,04), Solidago chilensis (0,1), Piper marginatum (0,2) para Staphylococcus aureus; Aloysia gratissima (0,1), P. marginatum (0,2), M. laevigata (0,09) para Bacillus subtilis e Mentha pullegium (0,3), Mikania glomerata (0,1), M. laevigata (0,04), Stachytarpeta cayenensis (0,2) e Bacharis dracunculifolia (0,5) para Streptococcus faecium. De acordo com os resultados, ressaltamos a espécie M. laevigata por apresentar inibição contra três das bactérias estudadas, em concentrações similares a do cloranfenicol, padrão de referência utilizado

Assessment of Baccharis trimera (Less.) DC. essential oil content in different packages during storage

The use of medicinal plants as therapeutic source is ancient and has increased in value in recent years for both the population and the science. Several national and international companies use raw plant material in the preparation of their products, making essential the commercial cultivation and the post-harvest processing of these species. The aim of this study was to evaluate the essential oil content of [Baccharis trimera (Less.) DC.] in three different packages over one year of storage. During storage, Kraft-paper package best preserved the integrity of some physical and chemical characteristics of the product and maintained the oil content for one year of storage.O uso de plantas medicinais como fonte terapêutica é milenar e nos últimos anos o seu valor tem aumentado, tanto para a população quanto para a ciência. Várias empresas nacionais e internacionais empregam matéria-prima vegetal na elaboração de seus produtos, o que torna indispensável o cultivo comercial e o beneficiamento pós-colheita destas espécies. O objetivo deste trabalho foi avaliar o teor de óleo essencial de carqueja [Baccharis trimera (Less.) DC.], em três embalagens diferentes ao longo de um ano de armazenamento. Observou-se que ao longo do armazenamento, a embalagem de papel Kraft foi a que melhor preservou a integridade de certas características físicas e químicas do produto, assim como, manteve o teor de óleo ao longo de um ano de armazenamento.545

Insights on the laccase extraction and activity in ionic-liquid-based aqueous biphasic systems

Due to their catalytic properties, selectivity, and efficiency, enzymes are excellent biocatalysts. In particular, laccases are versatile multi-copper oxidases with great interest for a wide plethora of biotechnological and environmental applications. Even though several laccase-catalysed processes have been reported at an industrial level, the high costs of their downstream processing required to provide biocatalysts with high purity levels, stability and activity remains one of the main drawbacks when economically evaluating the overall processes. Aqueous biphasic systems based on ionic liquids (ILs) can be foreseen as a promising alternative approach for the extraction and activity maintenance/improvement of enzymes, essentially due to the designer solvents ability of ionic liquids. However, to take advantage of this feature and to use the full potential of IL-based aqueous biphasic systems, it is necessary to understand the effect of ILs as phase-forming constituents and how they affect the enzymes extraction and activity. In order to overcome the lack of information on this topic in the literature, in this work, IL-based aqueous biphasic systems were investigated to extract and enhance the laccase activity, in order to gather evidences that could be used to improve the enzymes downstream processing. To this end, a wide screening of imidazolium-, pyridinium-, pyrrolidinium-, piperidinium-, tetraalkylphosphonium-, and tetraalkylammonium-based ILs as phase-forming components of ABS was carried out. Furthermore, these ILs were used to create ABS combined with salts, polymers and used as adjuvants in polymer-based ABS. Most ABS comprising ILs revealed to be highly efficient extraction platforms, allowing the complete extraction of laccase for all the conditions tested, and with an enzyme activity enhancement by more than 50%. Overall, the obtained results demonstrate that laccase preferentially partitions to the most hydrophilic phase in ABS comprising ILs, both used as adjuvants or as phase-forming components, corresponding to the phase in which the IL is enriched. Furthermore, the IL chemical structure of the IL plays a significant role in the enzyme activity, where ILs with a higher number of hydroxyl groups seem to be relevant to improve the laccase activity.publishe

Undamning the Douro river catchment: a stepwise approach for prioritizing dam removal

Dams provide water supply, flood protection, and hydropower generation benefits, but also harm native species by altering the natural flow regime, and degrading the aquatic and riparian habitats. In the present study, which comprised the Douro River basin located in the North of Portugal, the cost-benefit assessment of dams was based upon a balance between the touristic benefits of a dammed Douro, and the ecological benefits of less fragmented Douro sub-catchments. Focused on four sub-catchments (Sabor, Tâmega, Côa and Corgo), a probabilistic stream connectivity model was developed and implemented to recommend priorities for dam removal, where this action could significantly improve the movement of potadromous fish species along the local streams. The proposed model accounts for fish movement across the dam or weir (permeability), which is a novel issue in connectivity models. However, before any final recommendation on the fate of a dam or weir, the connectivity results will be balanced with other important socio-economic interests. While implementing the connectivity model, an inventory of barriers (dams and weirs) was accomplished through an observation of satellite images. Besides identification and location of any obstacles, the inventory comprised the compilation of data on surrounding land use, reservoir water use, characteristics of the riparian gallery, and permeability conditions for fish, among others. All this information was stored in a geospatial dataset that also included geographical information on the sub-catchment drainage network. The linear (drainage network) and point (barriers) source data were processed in a computer program that provided or returned numbers for inter-barrier stream lengths (habitat), and the barrier permeability. These numbers were finally used in the same computer program to calculate a habitat connector index, and a link improvement index, used to prioritize dam removal based upon structural connectivity criteria. The results showed that habitat patch connectivity in the Sabor, Tâmega and Côa sub-catchments is not dramatically affected by the installed obstacles, because most link improvement values were generally low. For the opposite reason, in the Corgo sub-catchment, obstacles may constitute a relatively higher limitation to connectivity, and in this case the removal of eight obstacles could significantly improve this connectivity. Using the probabilistic model of structural connectivity, it was possible to elaborate a preliminary selection of dams/weirs that critically limit stream connectivity, and that will be the focus of field hydraulic characterization to precisely determine fish movement along the associated river stretches. Future work will also include the implementation of a multi-criteria decision support system for dam removal or mitigation of the critical structures, as well to define exclusion areas for additional obstaclesinfo:eu-repo/semantics/publishedVersio

Effect of sequential medium on in vitro culture of goat ovarian cortical tissue

A sequential medium was evaluated on the survival, activation and growth rates of caprine preantral follicles submitted to a long-term culture period, aiming to establish an ideal in vitro culture system. Ovarian fragments were cultured for 16 days in α-MEM+ alone or supplemented with hormones (GH and/or FSH) added sequentially on different days of culture. Ovarian fragments were cultured in the first (days 0–8) and second (days 8–16) halves of the culture period, generating 10 treatments: α-MEM+/α-MEM+, FSH/FSH, FSH/GH, FSH/FSH + GH, GH/GH, GH/FSH, GH/FSH + GH, FSH + GH/FSH + GH, FSH + GH/FSH and FSH + GH/GH. Follicle morphology, viability and ultrastructure were analyzed. After day 1 of culture, FSH treatments maintained the percentage of normal follicles similar to the fresh control. At day 16 of culture, the treatment FSH/GH showed the highest (P < 0.05) percentage of normal follicles. The ultrastructure of follicles was preserved in the fresh control and FSH/GH treatment. Follicles cultured with FSH/GH had a higher (P < 0.05) viability than α-MEM+; however the viability was lower (P < 0.05) when compared to the fresh control. The FSH/GH treatment showed the highest (P < 0.05) percentage of follicular activation and secondary follicle formation and produced the largest (P < 0.05) mean follicular diameter after 16 days of culture. In conclusion, a sequential medium supplemented with FSH followed by GH during a long-term culture maintains the survival, viability and ultrastructure of goat preantral follicles, and promotes activation and secondary follicles

An MPEG-7 scheme for semantic content modelling and filtering of digital video

Abstract Part 5 of the MPEG-7 standard specifies Multimedia Description Schemes (MDS); that is, the format multimedia content models should conform to in order to ensure interoperability across multiple platforms and applications. However, the standard does not specify how the content or the associated model may be filtered. This paper proposes an MPEG-7 scheme which can be deployed for digital video content modelling and filtering. The proposed scheme, COSMOS-7, produces rich and multi-faceted semantic content models and supports a content-based filtering approach that only analyses content relating directly to the preferred content requirements of the user. We present details of the scheme, front-end systems used for content modelling and filtering and experiences with a number of users