Baccharis Research Articles

Secretory structures in Baccharis platypoda DC. inflorescences (Asteraceae) and characterization of the chemical composition of its secretion.

Rocky outcrop environments at high altitudes have nutrient-poor soil, where species are exposed to water scarcity and high solar radiation. Baccharis platypoda DC. occurs in such an environment and has a rigid and transparent secretion that covers the entire inflorescence. We analysed and compared the secretory structures and their chemical composition in female and male inflorescences of B. platypoda, a dioecious species, to explore chemodiversity within this species and assess potential differences between individuals. Our investigation also aims to understand the occurrence of these substances in the genus Baccharis L. Chemical compounds and secretory structures were similar in female and male inflorescences. There are glandular trichomes on the epidermis of the abaxial surface of bracts, and secretory ducts in the axis of the inflorescence, as well as in sepals, petals, and bracts. Histochemical tests were positive for phenolic compounds, flavonoids, proteins, pectin, and lipids, but not for mucilage. Flavonoid content varied between 6.24% and 9.81%, being higher in female inflorescences. Chromatography revealed the presence of several phenolic compounds, some terpenes, and other less frequent classes in both female and male inflorescences. We highlight that trichomes found on these surfaces produce abundant phenolic compounds. These act as natural defence agents, absorbing UV radiation and minimizing oxidative stress to plant cells. The chemical composition of the secretion covering the inflorescences may reflect adaptation and survival mechanisms of these organisms under extreme sun exposure.

The infusion of Baccharis spicata(Lam.) Baill (Asteraceae) has antiviral activity againsthepatitis B virus without cytotoxic effects against several cell lines

Medicinal plants are used to cure diseases, and their replacement is frequent and affects public health. The genus Baccharis has representatives within the medicinal flora of Argentina, although the replacement of the species of this genus known under the vulgar name of "carqueja" by Baccharis spicata has been detected in herbalists or markets of herbal products. The genotoxic safety of this species has been established in previous work of our group. The aim of this study was to evaluate the antiviral activity of an infusion made from B. spicata leaves against hepatitis B virus with the HepG2.2.15 cellular system and to determine cytotoxicity in HepG2.2,15, A549 and Vero cell lines. Infusion of B. spicata was active to inhibit HBV replication with an EC50of 22.54 μg/mL and a CC50of 190 μg/mL.

Suppression of inflammation by Baccharis punctulata and Baccharis trimera through modulation of innate and adaptive immune responses

Inflammatory processes, involving both innate and adaptive responses, are essential for controlling pathogens and maintaining homeostasis. However, excessive inflammation can cause chronic conditions including autoimmune diseases, atherosclerosis, and cancer. Alternative treatment options for inflammation are crucial, and exploring plants with anti-inflammatory properties holds significance. The genus Baccharis (Asteraceae family) is widespread across the Americas and is traditionally used to treat various disorders, including inflammatory diseases. Several biological activities of Baccharis species have been described; however, their immunomodulatory effects have not been widely evaluated. In this study, we analyzed the immunomodulatory activity of two Baccharis species, Baccharis punctulata, and Baccharis trimera, using an in vitro inflammation model involving monocytic cells and splenocytes to evaluate both innate and adaptive immune responses. Both B. punctulata and B. trimera reduced lipopolysaccharide (LPS)-induced inflammatory mediators, including soluble CD14 and pro-inflammatory cytokines, in THP-1 cells. Furthermore, they suppressed nitric oxide (NO) production in splenocytes, demonstrating a dampened innate immune response. In addition, both species attenuated concanavalin A (ConA)-induced splenocyte proliferation, suggesting an anti-inflammatory effect on the adaptive immune response. In summary, the extracts demonstrated significant anti-inflammatory activity, affecting both innate and adaptive immune responses, and underscoring their potential as treatments for inflammatory diseases and sources of anti-inflammatory molecules.

Antinociceptive effect of cyclic and linear diterpenoids as new atypical agonists of κ-opioid receptors obtained from four species of the Baccharis genus, and vehiculated in nanometric niosomes

New natural analgesic compounds that act in KORs are important alternatives for potential therapeutical use in medicine. In this work, we report and compare here the antinociceptive activity displayed by cyclic and linear diterpenes, obtained from the genus Baccharis. The antinociceptive activities determined were relatively strong, in comparison whit morphine. The antinociceptive mechanism of action was made through naloxone administration (a non-selective antagonist of opioid receptors). The more active compounds were vehiculized successfully in niosomes at nanometric scale. The observed antinociceptive activity for Bartemidiolide oxide (BARTO), obtain from Baccharis artemisioides, was greater than Flabeloic acid dimer (DACD), the first compound isolated from Baccharis flabellata that was reported possessing antinociceptive effects. We also conducted docking calculations and molecular dynamics simulations, which suggested that the newly identified diterpenes might share the molecular action mechanism reported for Salvinorin A (SalA). Molecular simulations have allowed us to appreciate some subtle differences between molecular interactions of these ligands stabilizing their respective complexes; such information might be useful for designing and searching for new inhibitors of KORs.

Calcium oxalate crystal macropattern and its usefulness in the taxonomy of Baccharis (Asteraceae).

This study provides a comprehensive account of the various types of calcium oxalate crystals found in the genus Baccharis and assesses the exceptional value of crystal macropatterns for the taxonomy of the genus. The morphotype, occurrence, and chemical composition of the crystals found in the stems and leaves are studied. The 44 species included in this study were selected based on a broad phylogeny-based sampling covering seven subgenera and 31 sections. These species were chosen to represent all the main phylogenetic lineages of Baccharis; thus, the sampling also represents a comprehensive coverage concerning evolutionary significance for such a large and environmentally and economically important plant group. The samples were analyzed by light microscopy, scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDS). Several morphotypes of crystals, including druses, crystal sand, styloids and prisms, were present. Based on their chemical composition, the crystals were classified as pure calcium oxalate, mixtures of oxalates and sulfates, and mixtures of oxalates, sulfates, and silica. The crystal macropatterns observed in this study aid in species identification and provide novel data for the taxonomy of Baccharis. RESEARCH HIGHLIGHTS: Most species of Baccharis have a specific crystalline pattern. Each species produces a crystal morphotype or a set of morphotypes specific to it. The crystals observed are formed by calcium oxalate.

Bio-Guided Isolation of New Compounds from Baccharis spp. as Antifungal against Botrytis cinerea.

Baccharis genus Asteraceae is widely used in traditional treatment against fever, headache, hepatobiliary disorders, skin ulcers, diabetes, and rheumatism, as well as an antispasmodic and diuretic. Its phytochemistry mainly shows the presence of flavonoids and terpenoids such as monoterpenes, sesquiterpenes, diterpenes, and triterpenes. Some of them have been evaluated for biological activities presenting allelopathic, antimicrobial, cytotoxic, and anti-inflammatory properties. In this paper, our research group reported the isolation, characterization, and antifungal evaluation of several molecules isolated from the dichloromethane extract from Baccharis prunifolia, Baccharis trinervis, and Baccharis zumbadorensis against the phytopathogen fungus Botrytis cinerea. The isolated compounds have not previously been tested against Botrytis, revealing an important source of antifungals in the genus Baccharis. Six known flavones were isolated from B. prunifolia. The dichloromethane extracts of B. trinervis and B. zumbadorensis were subjected to a bio-guided isolation, obtaining three known flavones, an α-hydroxidihydrochalcone mixture, one labdane, one triterpene, and two norbisabolenes from the most active fractions. The compounds 4'-methoxy-α-hydroxydihydrochalcone (7A), 3β,15-dihydroxylabdan-7-en-17-al (8), and 13-nor-11,12-dihydroxybisabol-2-enone (11) are novel. The most active compounds were the Salvigenin (5) and 1,2-dihydrosenedigital-2-one (10) with an IC50 of 13.5 and 3.1 μg/mL, respectively.

The role of Baccharis (Asteraceae) shrubs in the short-term restoration of Atlantic rainforest

The introduction of nurse species on degraded sites of Permanently Protected Areas represents a useful strategy for vegetation recovery in riparian forest. Species of the genus Baccharis (Asteraceae) have been documented as potential nurse plants being able of restructuring the native plant community. This study was aimed to evaluate the potential nursing role of Baccharis dracunculifolia in the recovery of a native plant community of a degraded Atlantic rainforest in a short-time period. The study was developed in two abandoned pasture areas in a riparian forest in the River Piranga basin, one in which B. dracunculifolia was planted (Restored treatment) to promote restoration, and a second area with no intervention (Degraded = Control treatment). Sampling took place 18 months after the planting of B. dracunculifolia. We set up 20 plots of 2 × 2 m in each treatment type (n = 40 plots), where all plant species were recorded (with the exception of the introduced Baccharis individuals and grasses), classifying them as native, ruderal, or alien. Plant richness was twice higher in the Restored treatment than the Degraded treatment. Furthermore, the observed values of alpha, gamma and beta diversity were also higher in Restored treatment. Restored treatment had 17 exclusive native species, while the Degraded treatment had only three non-exclusive native species. In addition, fewer ruderal and alien species were recorded in the restored plots with B. dracunculifolia compared to degraded plots. We concluded that, even in a short time period, planting B. dracunculifolia had a positive effect on promoting the assembly of the native plant community and possibly decreasing the chances of invasion by alien species.

Is it safe to consume medicinal plants in mined areas? Investigating possible effects caused by a metal-contaminated plant in southern Brazil

Mineral extraction areas are a significant environmental concern due to soil, water, and plant food resources contamination. Some medicinal plant species, such as those of the genus Baccharis, potentially bioaccumulate toxic elements. We evaluate the metal content from coal mining activity present in Baccharis sagittalis and in the soil; and whether this plant consumption represents a risk to human health. Cd and Pb presented levels that exceed those recommended by three global health agencies. Cd and Pb showed high levels in the projections of the daily intake recommended by international health agencies. After interviewing local residents close to mining areas, we found that 53.8 % of the interviewees mentioned the consumption of Baccharis sagittalis as infusion. These results indicate that the consumption of metal-contaminated Baccharis sagittalis can cause health problems as those metals accumulate in the human body. However, studies on Al, Ba, Cr, Cu, Mn, Ni, and Zn acceptable levels in plants consumed by humans are scarce. The contamination of plant species with associated traditional use close to mining areas can increase food security vulnerability of people who live near those areas and are constantly exposed to these agents, using plants gathered in the region.

Insecticidal and oviposition deterrent effects of essential oils of Baccharis spp. and histological assessment against Drosophila suzukii (Diptera: Drosophilidae)

The diverse flora of the Atlantic Forest is fertile ground for discovering new chemical structures with insecticidal activity. The presence of species belonging to the genus Baccharis is of particular interest, as these species have shown promise in pest management applications. The objective of this study is to chemically identify the constituents expressed in the leaves of seven species of Baccharis (B. anomala DC., B. calvescens DC., B. mesoneura DC., B. milleflora DC., B. oblongifolia Pers., B. trimera (Less) DC. and B. uncinella DC.) and to evaluate the toxicological and morphological effects caused by essential oils (EOs) on the larvae and adults of Drosophila suzukii (Diptera: Drosophilidae). Chemical analysis using gas chromatography-mass spectrometry (GC–MS) indicated that limonene was the main common constituent in all Baccharis species. This constituent in isolation, as well as the EOs of B. calvescens, B. mesoneura, and B. oblongifolia, caused mortality in over 80% of adults of D. suzukii at a discriminatory concentration of 80 mg L−1 in bioassays of ingestion and topical application. These results are similar to the effect of spinosyn-based synthetic insecticides (spinetoram 75 mg L−1) 120 h after exposure. Limonene and EOs from all species had the lowest LC50 and LC90 values relative to spinosyn and azadirachtin (12 g L−1) in both bioassays. However, they showed the same time toxicity over time as spinetoram when applied to adults of D. suzukii (LT50 ranging from 4.6 to 8.7 h) in a topical application bioassay. In olfactometry tests, 92% of D. suzukii females showed repellent behavior when exposed to the EOs and limonene. Likewise, the EOs of B. calvescens, B. mesoneura, and B. oblongifolia significantly reduced the number of eggs in artificial fruits (≅ 7.6 eggs fruit−1), differing from the control treatment with water (17.2 eggs fruit−1) and acetone (17.6 eggs fruit−1). According to histological analyses, the L3 larvae of D. suzukii had morphological and physiological alterations and deformations after exposure to treatments containing EOs and limonene, which resulted in high larval, pupal, and adult mortality. In view of the results, Baccharis EOs and their isolated constituent, limonene, proved to be promising alternatives for developing bioinsecticides to manage of D. suzukii.

Sobrevivência de larvas de Zebrafish (Danio rerio) expostas ao extrato hidroalcoólico de Baccharis dracunculifolia

O objetivo deste trabalho foi testar o efeito tóxico de diferentes concentrações de extrato hidroalcoólico da planta Baccharis dracunculifolia, utilizando larvas de zebrafish (Danio rerio) de 8 dias pós-fertilização. No primeiro ensaio 50,0, 25,0, 12,5, 6,25, 3,125, 1,563 e 0,781 mg/mL de extrato foram diluídos em H2O e foram realizadas observações em 0, 1 e 2 horas das larvas expostas ao extrato. No segundo ensaio, as diluições foram 2,0; 1,0; 0,40 e 0,20 mg/mL do extrato em H2O e exposição das larvas no extrato em 0, 4, 8 e 12 horas. A partir do desenvolvimento dos dois testes pode-se verificar que quando as larvas foram expostas a extratos de B. dracunculifolia com diluições superiores a 2,0 mg/mL, obteve-se 100% de mortalidade assim que a larva foi exposta. A exposição de larvas de zebrafish (Danio rerio) aos oito dias após-fertilização nos diferentes níveis de diluição do extrato hidro alcoólico de B. dracunculifolia apresentou efeitos letais. Porém, quando foram testadas diluições a partir de 0,40 mg/mL, obteve-se um baixo percentual de mortalidade.

1H HR-MAS NMR and chemometric methods for discrimination and classification of Baccharis (Asteraceae): A proposal for quality control of Baccharis trimera

Baccharis trimera is a species recognized by health agencies and recommended by the Brazilian Pharmacopoeia by having medicinal properties. In this work, HR-MAS NMR spectroscopy combined with chemometric tools, such as Principal Components Analysis (PCA), Partial Least Squares Discriminant Analysis (PLS-DA) and Soft Independent Modeling by Class Analogy (SIMCA), were used to evaluate the quality control and authenticity of commercial samples of Baccharis, as well as to discriminate B. trimera samples from other species of the Caulopterae section (B. articulata, B. trimera, B. junciformis, B. milleflora, and B. myriocephala). The high morphological similarity of these species makes it difficult for their identifications and discriminations, even by taxonomists. Different PCA pre-processing (autoscaling, Pareto scaling, and mean centering) allowed to discriminate B. trimera and B. myriocephala from the other species, mainly due to the presence of carquejyl acetate, indicated their chemical similarity. The 1H HR-MAS NMR spectral profile offers the possibility of tracking not only the chemical markers, such as the presence of carquejyl acetate, which can also be helpful in the B. trimera authentication/identification. The application of classification methods in standard samples revealed that PLS-DA models showed better performance on the calibration and validation sets than SIMCA model. However, PLS-DA and SIMCA applied to commercial samples showed that none of the commercial samples were classified as B. trimera, which suggested the lack of strict quality control regarding these products. The methodology developed in the present work might contribute to chemotaxonomy of the genus Baccharis.

GC-MS-FID and potentiation of the antibiotic activity of the essential oil of Baccharis reticulata (ruiz & pav.) pers. and α-pinene

The genus Baccharis (Asteraceae) demonstrated the presence of compounds with antibacterial, antifungal and antioxidant activities. Because of the increasing rates of antimicrobial resistance, adequate treatment of infections caused by Gram-negative bacteria has become challenging. The objective of the present study was evaluate the antibacterial and antibiotic-modifying activity of the essential oil obtained from Baccharis reticulata (Ruiz & Pav.) Pers. and the compound α-pinene against Pseudomonas aeruginosa and other multiresistant bacteria. An analysis by gas chromatography associated with mass spectrometry (GC/MS) revealed the presence of dilapiol (33.8 %), α-pinene (31.7 %) and β-pinene (9.4 %) as major components of the oil. The determination of the Minimum Inhibitory Concentration (MIC) revealed that the oil has antibacterial activity against S. aureus only. However, the oil potentiated the norfloxacin and gentamicin against all strains evaluated. Also, α-pinene increased the activity of norfloxacin against E. coli, as well as potentiated the activity of norfloxacin and gentamicin against S. aureus. Therefore, the authors conclude that the essential oil of B. reticulata, as well as the compound α-pinene, have antibacterial and antibiotic-modulating activities that make them useful in the development of new weapons against bacterial resistance.

Carqueja (Baccharis sect. Caulopterae), a critical review of its history, phytochemistry and medicinal use: problems of ethnopharmacology in Latin America

The Latin American medicinal plant carqueja got its name from a morphologically similar plant from the Iberian peninsula. The popular name came in general use to indicate all species from the section Caulopterae from the genus Baccharis, which are often difficult to distinguish. Phytochemical studies indicate that the different species from this section contain similar compound classes, especially essential oils, flavonoids and diterpenes, but much variation is encountered in relation to the individual compounds within the species. There are also some indications for the existance of different chemotypes within species. Recovered information from manuscripts, elaborated in the Jesuit missions, and originally authored by the Jesuit friar Pedro de Montenegro around 1710, indicate that carqueja was used by the Guarani indians of Southern Latin America for wound treatment. This traditional use was largely lost and nowadays the plant is mainly indicated for intestinal problems, as a tonic or for treatment of diabetes. It might be possible that this is caused by a confusion with quina, around 1800, which led to the alternative popular name “Quina de Condamine”. The confusion about the identification of individual species persists up to today. In pharmacological studies performed with crude extracts, doubts arise about the species used and its phytochemical composition. Also in medicinal teas different species are used indiscriminantly leading to great differences in phytochemical profile. In this paper information about the phytochemistry, medicinal use, botanical specimens and nomenclature is extensively reviewed and recommendations for further studies and increased reproducibility of pharmacological studies are given.

Therapeutic effect of Baccharis anomala DC. extracts on activated hepatic stellate cells.

The therapeutic potential of Baccharis anomala DC. extracts was evaluated through its cytotoxic and antiproliferative effect and their phenotypic reversion property in activated hepatic stellate cells (HSCs). Baccharis anomala is distributed in Brazil (southeastern and south regions) and used for diuretic effect in folk medicine. Four fractions were obtained from the fractionation of the methanolic extract. Fractions III and IV decreased cell proliferation without increasing cell necrosis markers levels and induced cell cycle arrest in G1 phase. Fraction III induced phenotypic reversion through PPAR-γ activation pathway, while fraction IV did not alter PPAR-α/γ expression levels, suggesting that there is an independent PPAR-α/γ pathway involved. Hydroxybenzoic, chlorogenic and coumaric acids were identified. Fractions III and IV showed antiproliferative effect and ability to induce reversion of activated phenotype of HSCs.

An unusual new record of Baccharis (Asteraceae) from the Peruvian Andes and its relation with the northern limit of the dry puna

Background and Aims: The knowledge of the richness and distribution of the flora in the Peruvian Andes is scarce; about 70 taxonomic novelties have been reported for this area in the last decade, a large part belonging to the Asteraceae. The objective of this paper is to contribute to the knowledge of this flora through a new record of Baccharis acaulis. In addition, the distribution pattern of this species is examined.Methods: As part of floristic inventories in the high Andes of Peru, various field trips were carried out, several plant specimens were collected, among them a previously unreported species, which was identified by consulting some specialists and confirmed using taxonomic keys. Furthermore, predicting species distribution based on ecological niche modeling was made use the machine learning algorithm Maxent with the bioclimatic variables of the WorldClim database.Key results: A species of the genus Baccharis was registered for the first time for the flora of Peru. This species is recognized for its unique habit; it is a rhizomatous herb in which the aboveground part consists of small leaf rosettes surrounding a solitary capitulum. The species was collected in the south of the Peruvian Andes. This record extends the known distribution of the species considerably to the north.Conclusions: This record suggests the need to continue studying the Andean flora, as well as the links of their distribution patterns with the phytogeographical regions.

Plant extracts of three species of the genus Baccharis induce human mononuclear cells proliferation

Las plantas de uso en medicina tradicional constituyen una fuente importante de compuestos con actividad inmunomoduladora; entre ellas las especies del genero Baccharis, conocidas popularmente como “Jaguareteka´a” en nuestro pais, son ampliamente empleadas. En este estudio se evaluo la actividad inmunomoduladora de extractos metanolicos de tres especies del genero Baccharis (B. trimera, B. notosergilay B. punctulata) sobre la proliferacion de celulas mononucleares humanas de sangre periferica. Los extractos de las tres especies estudiadas estimularon la proliferacion de las celulas mononucleares. Especificamente, el extracto de B. notosergila estimulo la proliferacion celular a todas las concentraciones probadas (5, 10, 25 y 50 μg/mL), mientras que los extractos de B. trimera y B. punctulata mostraron este efecto a 5 y 10 μg/mL. Ademas, por presentar mayor induccion de la proliferacion, se realizo un fraccionamiento con diferentes solventes del extracto metanolico de B. notosergila y B. punctulata. La fraccion de acetato de etilo de ambos extractos vegetales aumento la proliferacion celular, sugiriendo que compuestos de polaridad media son los responsables de esta actividad. Estos resultados demuestran que los extractos de B. trimera, B. notosergila y B. punctulata poseen actividad inmunomoduladora sobre celulas mononucleares humanas y serviran de base a otros estudios para determinar el o los componentes activos de los extractos sobre el sistema inmune.

Inducing resistance in cotton against Colletotrichum gossypii var. cephalosporioides with essential oils

This study aimed to evaluate the potential of essential oils of rosemary ( Rosmarinus officinalis ), baccharis ( Baccharis trimera ), lemon grass ( Cymbopogon citratus ), basil ( Ocimum basilicum ) and eucalyptus ( Corymbia citriodora ) in inducing resistance in cotton plants against C. gossypii var. cephalosporioides . The inductive effect of the essential oils was evaluated in plants growing in pots in the environment, which were treated with 1% essential oil at 47 days of age. 24 hours after elicitor treatment the plants were inoculated with a suspension of 1.5 x 10 5 conidia mL -1 of C. gossypii var. cephalosporioides . Five evaluations were performed disease and calculated the area under the disease progress curve. All essential oils showed potential for inducing resistance against cotton C. gossypii var. cephalosporioides .

Olfactometry evaluation and antimicrobial analysis of essential oils from Baccharis dentata (Vell.) G.M. Barroso and Baccharis uncinella DC.

The species of genus Baccharis spp. (Compositae) are an important natural resource in the search for new bioactive compounds. This article presents an investigation of volatile compounds of two species of Baccharis that are native to southern Brazil (Baccharis dentata (Vell.) G.M. Barroso and Baccharis uncinella DC) collected in summer and autumn of 2011. The essential oils were extracted by steam distillation and analyzed by gas chromatography-mass spectrometry (GC-MS), olfactometry analysis (GC-O) and qualitative assessment of the antimicrobial potential using the indirect bioautography method against Staphylococcus aureus, Salmonella enterica subspecie enterica serovar Choleraesuis, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger, Candida parapsilosis, Cryptococcus neoformans, Rhizopus stolonifer, Fusarium solani and Aspergillus oryzae. The results demonstrated that the harvest period has an influence on the composition of the essential oils, but little influence on extraction yield. It can also be observed that the joint analysis of GC-MS and GC-O resulted in complementary information about the essential oils studied because the intensities of volatile compounds detected by both methods are significantly different. Regarding antimicrobial assays, it was found that the essential oil of B. dentata was effective against S. aureus, A. niger, C. parapsilosis and R. stolonifer, whereas the essential oil of B. uncinella was effective against S. aureus, S. Choleraesuis, C. albicans, A. niger, C. parapsilosis, R. stolonifer and F. solani.

Macrocyclic trichothecenes as antifungal and anticancer compounds.

Trichothecenes are sesquiterpenoid metabolites produced by fungi and species of the plant genus Baccharis, family Asteraceae. They comprise a tricyclic core with an epoxide at C-12 and C-13 and can be grouped into non-macrocyclic and macrocyclic compounds. While many of these compounds are of concern in agriculture, the macrocyclic metabolites have been evaluated as antiviral, anti-cancer, antimalarial and antifungal compounds. Some known cytotoxic responses on eukaryotic cells include inhibition of protein, DNA and RNA syntheses, interference with mitochondrial function, effects on cell division and membranes. These targets however have been elucidated essentially employing non-macrocyclic trichothecenes and only one or two closely related macrocyclic compounds. For several macrocyclic trichothecenes high selectivity against fungal species and against cancer cell lines have been reported suggesting that the macrocycle and its stereochemistry are of crucial importance regarding biological activity and selectivity. This review is focused on compounds belonging to the macrocyclic type, where a cyclic diester or triester ring binds to the trichothecane moiety at C-4 and C- 15 leading to natural products belonging to the groups of satratoxins, verrucarins, roridins, myrotoxins and baccharinoids. Their biological activities, cytotoxic mechanisms and structure-activity relationships (SAR) are discussed. From the reported data it becomes evident that even small changes in the molecules can lead to pronounced effects on biological activity or selectivity against cancer cells lines. Understanding the underlying mechanisms may help to design highly specific drugs for cancer therapy.

Screening for anti-inflammatory activity of Baccharis species using in silico models

Natural products have always played a vital role in drug discovery. Asteraceae species have showed potent anti-inflammatory activity against cyclooxygenase-1 (COX-1) and 5-lipoxygenase (5-LOX) enzymes [1]. The genus Baccharis has more than 400 species and some of them present anti-inflammatory activity. This study aimed at screening extracts of Baccharis for their anti-inflammatory potential using UHPLC-HRMS and in silico models. EtOH:H2O (7:3 v/v) extracts of 223 Baccharis species and 33 other Asteraceae were prepared, their fingerprints were obtained and processed by MZmine. SIMCA-P was used for multivariate analysis and Partial Least Squares Discriminant Analysis (PLS-DA) was used to build prediction models. The model was based on extracts of 14 Asteraceae species that previously presented dual inhibition against COX and LOX and the remaining species presented one or no inhibition. The PLS model was build with two-thirds for training and one-third for testing. As a result, a matrix was obtained with 4,758 variables from the negative mode of ionization. After validation, the PLS-DA model showed statistical significance (p < 0.05, 95% confidence level) and coefficients of determination (R2) and prediction (Q2) of 0.99 and 0.65, respectively. The model was able to sort 50% correctly to Baccharis species, where a total of 100 species can present dual inhibition. Among the tested species, B. boliviensis, B. subalata and B. incarum can be cited for their dual inhibition for the first time. Therefore, the purposed model was able to filter the species with anti-inflammatory potential, and this way to avoid waste of time and money.