The relative importance of local ecological and larger-scale historical processes in causing differences in species richness across the globe remains keenly debated. To gain insight into these questions, we investigated the assembly of plant diversity in the Cerrado in South America, the world's most species-rich tropical savanna. Time-calibrated phylogenies suggest that Cerrado lineages started to diversify less than 10 Mya, with most lineages diversifying at 4 Mya or less, coinciding with the rise to dominance of flammable C4 grasses and expansion of the savanna biome worldwide. These plant phylogenies show that Cerrado lineages are strongly associated with adaptations to fire and have sister groups in largely fire-free nearby wet forest, seasonally dry forest, subtropical grassland, or wetland vegetation. These findings imply that the Cerrado formed in situ via recent and frequent adaptive shifts to resist fire, rather than via dispersal of lineages already adapted to fire. The location of the Cerrado surrounded by a diverse array of species-rich biomes, and the apparently modest adaptive barrier posed by fire, are likely to have contributed to its striking species richness. These findings add to growing evidence that the origins and historical assembly of species-rich biomes have been idiosyncratic, driven in large part by unique features of regional- and continental-scale geohistory and that different historical processes can lead to similar levels of modern species richness.

https://www.pnas.org/content/pnas/106/48/20359.full.pdf

Recent assembly of the Cerrado, a neotropical plant diversity hotspot, by in situ evolution of adaptations to fire

OBJECTIVE To establish an indirect immunofluorescent test so as to improve the sensitivity and specificity of examination of antibodies to beta(2)-glycoprotein METHODS Full-length beta(2)GP cDNA was obtained from human hepatocellular cancer cell line HepG2 by RT-PCR and cloned into the mammalian expression vector pEGFP-C1 The recombinant plasmid pEGFP-beta(2)GP was transfected into HEp-2 cells RT-PCR, immunoblotting (IBT), confocal fluorescence microscopy, and indirect immunofluorescent test (IIF) were used to confirm the expression, localization, and antigenicity of fusion protein of green fluorescent protein (GFP) Serum specimens from 19 patients suspected as with secondary antiphospholipid syndrome (APS), 1 patient diagnosed as with primary APS, and 10 normal persons were detected with IIF-IgG-beta(2)GP1, ELISA-IgG-ACL, and ELISA-IgG-beta(2)GP I simultaneously RESULTS (1) The HEp-beta(2)GP I cells thus obtained retained their ability of expression of beta(2)GP-I-GFP for more than ten generations This beta(2)GP-I-GFP showed the antigenicity of beta(2)GP-I with a characteristic feature (2) Seven of the 20 serum specimens from APS patients showed characteristic immunofluorescent pattern No serum specimen from normal persons showed immunofluorescent staining The comparison of results of the three methods showed that the concordance between IIF-IgG-beta(2)GP I and ELISA-IgG-beta(2)GP I was the most perfect (Kappa = 0886) (3) HEp-beta(2)GP I retained the immunofluorescent property of HEp-2 cell CONCLUSION As a new kind of substrate of IIF, beta(2)GP I transfectant can be used to detect anti-beta(2)GP-I antibodies Transfeted HEp-2 cells keep the immunofluorescent property of HEp-2 cells in IFANA test and can be used as substrate for routine IFANA detection

[Expression of fusion proteins in beta(2)GP I gene-transfected HEp-2 cells and its clinical application].

Flavonoids are one of the largest classes of small molecular secondary metabolites produced in different parts of the plant. They display a wide range of pharmacological and beneficial health effects for humans, which include, among others, antioxidative activity, free radical scavenging capacity, coronary heart disease prevention and antiatherosclerotic, hepatoprotective, anti-inflammatory, and anticancer activities. Hence, flavonoids are gaining high attention from the pharmaceutical and healthcare industries. Notably, plants synthesize flavonoids in response to microbial infection, and these compounds have been found to be a potent antimicrobial agent against a wide range of pathogenic microorganisms in vitro. Antimicrobial action of flavonoids results from their various biological activities, which may not seem very specific at first. There are, however, promising antibacterial flavonoids that are able not only to selectively target bacterial cells, but also to inhibit virulence factors, as well as other forms of microbial threats, e.g. biofilm formation. Moreover, some plant flavonoids manifest ability to reverse the antibiotic resistance and enhance action of the current antibiotic drugs. Hence, the development and application of flavonoid-based drugs could be a promising approach for antibiotic-resistant infections. This review aims to improve our understanding of the biological and molecular roles of plant flavonoids, focusing mostly on their antimicrobial activities.

/pdf/comprehensive-review-of-antimicrobial-activities-of-plant-3i1u06eplg.pdf

Comprehensive review of antimicrobial activities of plant flavonoids

Molecular phylogenetic studies have become a major area of interest in plant systematics, and their impacts on historical biogeographic hypotheses are not to be disregarded. In Brazil, most historical biogeographic studies have relied on animal phylogenies, whereas plant biogeographic studies have largely lacked a phylogenetic component, having a limited utility for historical biogeography. That country, however, is of great importance for most biogeographic studies of lowland tropical South America, and it includes areas from a number of biogeographic regions of the continent. Important biogeographic reports have been published as part of phylogenetic studies, taxonomic monographs, and regional accounts for small areas or phytogeographic domains, but the available information is subsequently scattered and sometimes hard to find. In this paper we review some relevant angiosperm biogeographic studies in Brazil. Initially we briefly discuss the importance of other continents as source areas for the South American flora. Then we present a subdivision of Brazil into phytogeographic domains, and we cite studies that have explored the detection of biogeographic units (areas of endemism) and how they are historically related among those domains. Examples of plant taxa that could be used to test some biogeographic hypotheses are provided throughout, as well as taxa that exemplify several patterns of endemism and disjunction in the Brazilian angiosperm flora.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1759-6831.2009.00046.x

Review of plant biogeographic studies in Brazil

Leishmaniasis is a parasitic disease that presents four main clinical syndromes: cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL), visceral leishmaniasis/kala azar (VL), and post kala azar dermal leishmaniasis (PKDL). Causative Leishmania are protozoan parasites that are transmitted among mammalian hosts by phlebotomine sandflies. In mammalian hosts, parasite cells proliferate inside the host phagocytic cells as round amastigotes. Infection of sandflies with Leishmania occurs during insect feeding on infected mammalian hosts. After introduction into the insect gut together with the blood meal, Leishmania amastigotes transform into elongated flagellated promastigotes that propagate in the insect gut. A new round of infection is initiated after the infected sandfly takes a blood meal from a naive mammalian host and introduces Leishmania parasites into the bite wound in the host dermis (Scheme 1). More than 20 different Leishmania species have been found to cause human leishmaniasis (Table 1).

Leishmaniasis is endemic in 98 countries and is closely associated with poverty. More than a million new cases are reported per year and 350 million people are at risk of contracting the infection. For the most severe form of leishmaniasis, VL, ∼300 000 new cases are estimated to occur annually resulting in ∼40 000 deaths. Approximately 90% of all VL cases occur in 3 endemic foci: 1. India, Bangladesh, and Nepal; 2. East Africa; and 3. Brazil. In spite of the high prevalence, currently available treatments for leishmaniasis are inadequate. Pentavalent antimonials, the standard treatment for leishmaniasis for many decades, are not efficacious in Bihar (∼60% of VL cases worldwide) any longer due to widespread resistance to the drug in this region. Several new VL treatments have emerged during the past 10–15 years, but each has serious shortcomings (summarized in Table 2). These include paromomycin (injectable, long treatment, region-dependent efficacy), miltefosine (cost, teratogenicity, long treatment), and liposomal amphotericin B (cost, hospitalization, region-dependent efficacy). An additional challenge is represented by patients with HIV/VL coinfections who are more difficult to cure (lower initial and final cure rates), have greater susceptibility to drug toxicity, and have higher rates of death and relapse.

Due to the limitations of the existing treatments, better drugs are urgently needed. Ideally, new VL drugs would be efficacious across all endemic regions, would affect cure in ≤10 days, and would cost <$10 per course (for a complete target product profile for new VL drugs, which was formulated by DNDi, see Table 4).1 Here we describe the disease history and parasite biology followed by a summary of the currently available treatments and, finally, review reports of novel small molecules with antileishmanial activity.

Recent developments in drug discovery for leishmaniasis and human African trypanosomiasis.

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined by the WHO. Furthermore, malaria (caused by various Plasmodium species) can be considered a neglected disease in certain countries and with regard to availability and affordability of the antimalarials. Living organisms, especially plants, provide an innumerable number of molecules with potential for the treatment of many serious diseases. The current review attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs. In part I, a general description of the diseases, the current state of therapy and need for new therapeuticals, assay methods and strategies applied in the search for new plant derived natural products against these diseases and an overview on natural products of terpenoid origin with antiprotozoal potential were given. The present part II compiles the current knowledge on natural products with antiprotozoal activity that are derived from the shikimate pathway (lignans, coumarins, caffeic acid derivatives), quinones of various structural classes, compounds formed via the polyketide pathways (flavonoids and related compounds, chromenes and related benzopyrans and benzofurans, xanthones, acetogenins from Annonaceae and polyacetylenes) as well as the diverse classes of alkaloids. In total, both parts compile the literature on almost 900 different plant-derived natural products and their activity data, taken from over 800 references. These data, as the result of enormous efforts of numerous research groups world-wide, illustrate that plant secondary metabolites represent an immensely rich source of chemical diversity with an extremely high potential to yield a wealth of lead structures towards new therapies for NTDs. Only a small percentage, however, of the roughly 200,000 plant species on earth have been studied chemically and only a small percentage of these plants or their constituents has been investigated for antiprotozoal activity. The repository of plant-derived natural products hence deserves to be investigated even more intensely than it has been up to present.

The Potential of Secondary Metabolites from Plants as Drugs or Leads Against Protozoan Neglected Diseases – Part I

The internal transcribed spacer (ITS) region of the nuclear ribosomal
 DNA was sequenced from 21 accessions of Viguiera from South America,
 including 14 from Brazil. Overall there was only a small amount of sequence
 variation, less than 3.4% among South American samples and less than
 4.5% between the South American samples and the Mexican V. flava. Phylogenetic analysis revealed little divergence among the Brazilian
 samples of Viguiera. The low level of ITS sequence variation was
 in striking contrast to the taxonomic diversity and chemical variability that
 have been reported for Viguiera in Brazil. The low level of sequence
 variation suggests that, despite its clear morphological and phytochemical
 adaptations to the cerrado, Viguiera is probably a relatively recent
 addition (less than 3 million years) to the flora of this area.

Brazilian species of viguiera ( asteraceae ) exhibit low levels of its sequence variation

A proposal for chemical characterisation and quality evaluation of botanical raw materials by analysing the glandular trichomes from the leaves of two different populations of yacon (Polymnia sonchifolia Poeppig & Endlicher, Asteraceae) is described. This species is an Andean medicinal plant and the tea prepared with their leaves displays hypoglycemic property. The method was based on the glandular trichome microsampling using LC/DAD. Qualitative chromatographic fingerprints of the glands were obtained by isocratic runs and then compared between the two populations, showing the same qualitative profile. The two main metabolites detected in the glands were later isolated from a leaf rinse extract by preparative separation and identified as the melampolides enhydrin and uvedalin. These compounds, subtypes of sesquiterpene lactones, were used as chemical markers. This technique is applicable to other medicinal plants and can be used for the evaluation of the quality of dried material or leaf rinse extracts.

/pdf/a-proposal-for-chemical-characterization-and-quality-1leej7fr2p.pdf

A proposal for chemical characterization and quality evaluation of botanical raw materials using glandular trichome microsampling of yacón (Polymnia sonchifolia, Asteraceae), an Andean medicinal plant

LC-MS metabolic profiling comparison of domesticated crops and wild edible species from the family Asteraceae growing in a region of São Paulo state, Brazil

FB Da Costa

Papers

The Potential of Secondary Metabolites from Plants as Drugs or Leads Against Protozoan Neglected Diseases – Part I

Brazilian species of viguiera ( asteraceae ) exhibit low levels of its sequence variation

A proposal for chemical characterization and quality evaluation of botanical raw materials using glandular trichome microsampling of yacón (Polymnia sonchifolia, Asteraceae), an Andean medicinal plant

LC-MS metabolic profiling comparison of domesticated crops and wild edible species from the family Asteraceae growing in a region of São Paulo state, Brazil

Temporal characteristics of a natural products in-house database