RESUMO
The study aimed to assess the chemical composition of Miconia ibaguensis leaves extracts and fractions obtained from the ethanolic extract (EE), along with evaluating their antifungal, antibacterial, antidiabetic, and antioxidant activities. The ethyl acetate fraction (EAF) exhibited potent antifungal activity against Candida spp (1.95-3.90â µg mL-1) and potent antioxidant activity in the DPPH (1.74±0.07â µg mL-1), FRAP (654.01±42.09â µmol ETrolox/gsample), and ORAC (3698.88±37.28â µmol ETrolox/gsample) methods. The EE displayed inhibition against the α-amylase enzyme (8.42±0.05â µg mL-1). Flavonoids, hydrolysable tannins, triterpenoids, and phenolic acids, identified in the EE and fractions via (-)-HPLC-ESI-MS/MS analysis, were found to contribute to the species' biological activity potentially. These findings suggest promising avenues for further research and potential applications in pharmacology and natural products, offering new possibilities in the fight against global health issues.
Assuntos
Antibacterianos , Antifúngicos , Antioxidantes , Hipoglicemiantes , Melastomataceae , Testes de Sensibilidade Microbiana , Extratos Vegetais , Folhas de Planta , Folhas de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Melastomataceae/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Candida/efeitos dos fármacos , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Cromatografia Líquida de Alta PressãoRESUMO
Species in the Melastomataceae (Myrtales) include trees and woody shrubs that are amongst the most common hosts of Chrysoporthe and related fungi. These fungi cause stem cankers, branch death and in extreme cases, kill their hosts. Chrysoporthe-like fungi were observed on Miconia spp. and Rhynchanthera grandiflora (Melastomataceae) plants during tree disease surveys in south-eastern Brazil including the states of Minas Gerais and Rio de Janeiro. The aims of this study were to isolate and identify the fungi utilising morphological characteristics and phylogenetic analyses. This led to the identification of a new species of Chrysoporthe described here as Chrysoporthe brasilensis sp.nov. Inoculations were conducted on R. grandiflora and M. theaezans, showing that C. brasiliensis is an aggressive pathogen. This study adds to a growing number of reports of new and pathogenic species of Chrysoporthe that potentially threaten native Myrtales globally, including important trees such as Eucalyptus, both in natural ecosystems and in planted forests.
Assuntos
Melastomataceae , Filogenia , Doenças das Plantas , Brasil , Melastomataceae/microbiologia , Doenças das Plantas/microbiologia , DNA Fúngico/genética , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , DNA Ribossômico/genética , Análise de Sequência de DNA , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/química , Análise por ConglomeradosRESUMO
The recent availability of open-access repositories of functional traits has revolutionized trait-based approaches in ecology and evolution. Nevertheless, the underrepresentation of tropical regions and lineages remains a pervasive bias in plant functional trait databases, which constrains large-scale assessments of plant ecology, evolution, and biogeography. Here, we present MelastomaTRAITs 1.0, a comprehensive and updatable database of functional traits for the pantropical Melastomataceae, the ninth-largest angiosperm family with 177 genera and more than 5800 species. Melastomataceae encompass species with a wide diversity of growth forms (herbs, shrubs, trees, epiphytes, and woody climbers), habitats (including tropical forests, savannas, grasslands, and wetlands from sea level to montane areas above the treeline), ecological strategies (from pioneer, edge-adapted and invasive species to shade-tolerant understory species), geographic distribution (from microendemic to continental-wide distribution), reproductive, pollination, and seed dispersal systems. MelastomaTRAITs builds on 581 references, such as taxonomic monographs, ecological research, and unpublished data, and includes four whole-plant traits, six leaf traits, 11 flower traits, 18 fruit traits, and 27 seed traits for 2520 species distributed in 144 genera across all 21 tribes. Most data come from the Neotropics where the family is most species-rich. Miconieae (the largest tribe) contains the highest number of trait records (49.6%) and species (41.1%) records. The trait types with the most information in the database were whole-plant traits, flowers, and leaf traits. With the breadth of functional traits recorded, our database helps to fill a gap in information for tropical plants and will significantly improve our capacity for large-scale trait-based syntheses across levels of organization, plant-animal interactions, regeneration ecology, and thereby support conservation and restoration programs. There are no copyright restrictions on the dataset; please cite this data paper when reusing the data.
Assuntos
Bases de Dados Factuais , Melastomataceae , Ecossistema , Melastomataceae/fisiologia , Melastomataceae/genéticaRESUMO
In plant tissue culture, differences in endogenous levels of species-specific plant growth regulators (PGRs) may explain differences in regenerative capacity. In the case of polyamines (PAs), their dynamics and distribution may vary between species, genotypes, tissues, and developmental pathways, such as sexual reproduction and apomixis. In this study, for the first time, we aimed to assess the impact of varying endogenous PAs levels in seeds from distinct reproductive modes in Miconia spp. (Melastomataceae), on their in vitro regenerative capacity. We quantified the free PAs endogenous content in seeds of Miconia australis (obligate apomictic), Miconia hyemalis (facultative apomictic), and Miconia sellowiana (sexual) and evaluated their in vitro regenerative potential in WPM culture medium supplemented with a combination of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). The morphogenic responses were characterized by light microscopy and scanning electron microscopy and discussed regarding the endogenous PAs profiles found. Seeds of M. sellowiana presented approximately eight times more putrescine than M. australis, which was associated with a higher percentage of regenerated calluses (76.67%) than M. australis (5.56%). On the other hand, spermine levels were significantly higher in M. australis. Spermine is indicated as an inhibitor of auxin-carrying gene expression, which may have contributed to its lower regenerative capacity under the tested conditions. These findings provide important insights into in vitro morphogenesis mechanisms in Miconia and highlight the significance of endogenous PA levels in plant regeneration. These discoveries can potentially optimize future regeneration protocols in Miconia, a plant group still underexplored in this area.
Assuntos
Melastomataceae , Poliaminas , Regeneração , Sementes , Sementes/fisiologia , Melastomataceae/fisiologia , Melastomataceae/metabolismo , Melastomataceae/química , Poliaminas/metabolismo , Regeneração/fisiologiaRESUMO
We evaluated the phenology and reproductive phenological diversity of three sympatric species of Miconia in a gallery forest in the Chapada Diamantina mountains, Bahia, Brazil. The reproductive phenophases (bud, flower, immature fruit, and mature fruit) of M. alborufescens (N=38), M. holosericea (N=46), and M. prasina (N=44) were evaluated monthly, between June/2008 and June/2015. The Fournier index was used to assess the intensities of the reproductive phenophases; synchrony and seasonality were analyzed using circular statistics and the Rayleigh (Z) test. The Frideman and Wilcoxon tests were used to verify interannual variations in phenological patterns. Reproductive phenological diversity was measured by calculating the Shannon-Wiener index; ANOVA tested possible differences in the means of diversity among the different years. The reproductive phenophases of the studied Miconia species occurred sequentially (M. alborufescens, then M. holoserica, followed by M. prasina), in the transition between the dry and rainy seasons, with little overlap between them. In general, the species showed seasonal and synchronic phenological patterns, with some variations that coincided with El Niño and/or La Niña events, e.g., demonstrating changes in the periodicity, synchrony, and intensity of their phenophases. The intensity of fruiting, for example, showed increases during La Niña years. Reproductive phenological diversity appears to respond to climate changes resulting from El Niño events and periods of prolonged drought, with high Shannon-Wiener index values. The results also suggest that the effects of global climatic phenomena (El Niño and La Niña) that alter regional climatic seasonality can also cause variations in the reproductive phenological rhythms of the Miconia species studied.
Assuntos
Melastomataceae , Floresta Úmida , Estações do Ano , Florestas , Chuva , El Niño Oscilação SulRESUMO
BACKGROUND: Given the rising occurrence of antibiotic resistance due to the existence and ongoing development of resistant bacteria and phenotypes, the identification of new treatments and sources of antimicrobial agents is of utmost urgency. An important strategy for tackling bacterial resistance involves the utilization of drug combinations, and natural products derived from plants hold significant potential as a rich source of bioactive compounds that can act as effective adjuvants. This study, therefore, aimed to assess the antibacterial potential and the chemical composition of Miconia albicans, a Brazilian medicinal plant used to treat various diseases. METHODS: Ethanolic extracts from leaves and stems of M. albicans were obtained and subsequently partitioned to give the corresponding hexane, chloroform, ethyl acetate, and hydromethanolic phases. All extracts and phases had their chemical constitution investigated by HPLC-DAD-MS/MS and GC-MS and were assessed for their antibiofilm and antimicrobial efficacy against Staphylococcus aureus. Furthermore, their individual effects and synergistic potential in combination with antibiotics were examined against clinical strains of both S. aureus and Acinetobacter baumannii. In addition, 10 isolated compounds were obtained from the leaves phases and used for confirmation of the chemical profiles and for antibacterial assays. RESULTS: Based on the chemical profile analysis, 32 compounds were successfully or tentatively identified, including gallic and ellagic acid derivatives, flavonol glycosides, triterpenes and pheophorbides. Extracts and phases obtained from the medicinal plant M. albicans demonstrated synergistic effects when combined with the commercial antibiotics ampicillin and ciprofloxacin, against multi-drug resistant bacteria S. aureus and A. baumannii, restoring their antibacterial efficacy. Extracts and phases also exhibited antibiofilm property against S. aureus. Three key compounds commonly found in the samples, namely gallic acid, quercitrin, and corosolic acid, did not exhibit significant antibacterial activity when assessed individually or in combination with antibiotics against clinical bacterial strains. CONCLUSIONS: Our findings reveal that M. albicans exhibits remarkable adjuvant potential for enhancing the effectiveness of antimicrobial drugs against resistant bacteria.
Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Melastomataceae , Plantas Medicinais , Staphylococcus aureus , Ciprofloxacina/farmacologia , Plantas Medicinais/química , Espectrometria de Massas em Tandem , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Ampicilina/farmacologia , Anti-Infecciosos/farmacologia , BactériasRESUMO
(1) Background: Malignant gliomas are aggressive tumors characterized by fast cellular growth and highly invasive properties. Despite all biological and clinical advances in therapy, the standard treatment remains essentially palliative. Therefore, searching for alternative therapies that minimize adverse symptoms and improve glioblastoma patients' outcomes is imperative. Natural products represent an essential source in the discovery of such new drugs. Plants from the cerrado biome have been receiving increased attention due to the presence of secondary metabolites with significant therapeutic potential. (2) Aim: This study provides data on the cytotoxic potential of 13 leaf extracts obtained from plants of 5 families (Anacardiaceae, Annonaceae, Fabaceae, Melastomataceae e Siparunaceae) found in the Brazilian cerrado biome on a panel of 5 glioma cell lines and one normal astrocyte. (3) Methods: The effect of crude extracts on cell viability was evaluated by MTS assay. Mass spectrometry (ESI FT-ICR MS) was performed to identify the secondary metabolites classes presented in the crude extracts and partitions. (4) Results: Our results revealed the cytotoxic potential of Melastomataceae species Miconia cuspidata, Miconia albicans, and Miconia chamissois. Additionally, comparing the four partitions obtained from M. chamissois crude extract indicates that the chloroform partition had the greatest cytotoxic activity against the glioma cell lines. The partitions also showed a mean IC50 close to chemotherapy, temozolomide; nevertheless, lower toxicity against normal astrocytes. Analysis of secondary metabolites classes presented in these crude extracts and partitions indicates the presence of phenolic compounds. (5) Conclusions: These findings highlight M. chamissois chloroform partition as a promising component and may guide the search for the development of additional new anticancer therapies.
Assuntos
Antineoplásicos , Glioma , Melastomataceae , Humanos , Brasil , Clorofórmio , Linhagem Celular , Antineoplásicos/farmacologia , Extratos Vegetais/farmacologia , Melastomataceae/química , Glioma/tratamento farmacológico , EcossistemaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Miconia albicans have been extensively used as a traditional medicine to treat inflammation, infection, arthritis, joint pain, and analgesia, which can be purchased easily. Nevertheless, the scientific evidence of chemical profile identification and toxicity investigation is meager. AIM OF THE STUDY: This study aimed to determine the chemical profile of Miconia albicans aqueous extract (MAAE), to investigate its anti-inflammatory and hyperalgesic effects, and toxicity (acute and repeated-dose oral) in vivo studies. MATERIALS AND METHODS: MAAE was obtained by infusion method and its chemical constituents were analyzed and annotated by LC-DAD-MS. The in vivo tests were performed with male and female Swiss mice. Toxicity studies were examined by acute (2000 mg/kg) and repeated-dose oral assays (51.2; 256; 1280 mg/kg); anti-inflammatory evaluation was performed by paw edema and leukocyte migration, and anti-hyperalgesic properties were analyzed by abdominal writhing induced by acetic acid and formalin. The animals were treated by oral means with 51.2, 256, and 1280 mg/kg of MAAE. RESULTS: Twenty-four compounds were annotated from MAAE by LC-DAD-MS, such as ellagitannins, ellagic acid derivatives, flavan-3-ol, and O-glycosylated compounds, including flavonols, triterpenes, and megastigmanes. MAAE induced no significant toxicological effects in the acute and repeated-dose oral assays at lower doses and no histological changes were observed. Hematological and biochemical showed no significant alterations. The oral administration of MAAE 256 mg/kg inhibited the edematogenic effect and reduced the leukocyte migration. In addition, MAAE decreased the abdominal writhings induced by acetic acid and the paw-licking time by formalin assay. CONCLUSION: MAAE showed a significant reduction in inflammatory levels and leukocyte migration, revealing anti-hyperalgesic properties. Additionally, MAAE revealed no acute and repeated-doses toxicities.
Assuntos
Melastomataceae , Masculino , Feminino , Camundongos , Animais , Analgésicos/farmacologia , Extratos Vegetais/farmacologia , Carragenina , Anti-Inflamatórios/farmacologia , Hiperalgesia/tratamento farmacológico , Formaldeído , Edema/tratamento farmacológicoRESUMO
Galls display a multiplicity of traits, including colours, which are driven by pigment accumulation. Their conspicuousness has attracted researchers' attention and several hypotheses have been raised. However, plants themselves vary intra-specifically, including in their pigment concentrations. As galls are a result of host tissue development, colours may be a by-product of the host's own traits, being more conspicuous simply because the sites where galls develop already have the predisposition to accumulate more pigment. Here, we call this the host variation hypothesis. We test this hypothesis using the system of galls induced by Palaeomystella oligophaga on Macairea radula host plant. Using spectrophotometry, we calculated the Anthocyanin Reflectance Index (ARI) of gall projections, which are responsible for their characteristic colours. We tested the influence of occupant identity (galling insect or any natural enemy), gall volume, parenchyma thickness, height from the ground, ARI of leaf, ARI of gall surface and ARI of the respective stem. We corroborated the host variation hypothesis since the anthocyanin content in stems and in galls' projections were positively related. Moreover, anthocyanin in galls' projections was positively related to anthocyanin in the gall surface and negatively related to gall volume and parenchyma thickness. This shows that, besides the host specificities, galls' own traits may also be responsible for pigment accumulation, influencing their colours. In this study, using colour as an example, we show that although galls tend to be considered complex expressions of galling insects' stimuli, their traits may be simply influenced by previous and specific attributes of the host organs.
Assuntos
Melastomataceae , Mariposas , Animais , Tumores de Planta , Antocianinas , Plantas , Insetos , Interações Hospedeiro-ParasitaRESUMO
The antioxidant, photoprotective and antinociceptive Marcetia macrophylla active extract was investigated as an active ingredient in a sunscreen cream formulation. Thus, the M. macrophylla extract showed IC50 of 3.43 mg/ml of the antioxidant (DPPH∙ scavenging test) and Sun Protection Factor of 20.25 (SPF/UV-B, at 250 µg/ml) and UV-A of 78.09% (photobleaching trans-resveratrol test). The antinociceptive activity was superior to all standards tested using the in vivo acetic acid-induced writhing test (99.14% at the dose of 200 mg/kg) and the high-performance liquid chromatography coupled with diode array detector and mass spectroscopy multi-stage (HPLC-DAD-MS/MS) enabled the structural characterization of the quercetin-3-O-hexoside, quercetin-3-O-pentoside and quercetin-3-O-desoxihexoside. The pharmaceutical formulation containing the Marcetia macrophylla crude active extract was prepared and the physicochemical tests (organoleptic characteristics, pH analysis and centrifugation), the in vitro UVB (sun protection factor, SPF) and UVA (β-carotene) using the spectroscopic method were investigated. The formulation showed satisfactory results concerning the physicochemical parameters evaluated and active against the UV test. Thus, M. macrophylla showed biological activities with potential use in pharmaceutical preparations.
O extrato bruto de Marcetia macrophylla mostrou atividade antioxidante, fotoprotetora e antinociceptiva, sendo em seguida investigado como ingrediente ativo em uma formulação fotoprotetora. Assim, o extrato de M. macrophylla apresentou atividade antioxidante com IC50 de 3,43 mg/mL (teste de sequestro do DPPH∙) e Fator de Proteção Solar de 20,25 (FPS/UV-B, 250 µg/mL) e UV-A de 78,09% (teste de fotobranqueamento do trans-resveratrol). A atividade antinociceptiva usando o teste in vivo de contorções abdominais induzidas por ácido acético foi superior a todos os padrões testados (99,14% na dose de 200 mg/Kg). A análise por cromatografia líquida de alta eficiência acoplada a detector de fotodiodos e espectroscopia de massas multi-estágio (CLAE-DAD-EM/EM) possibilitou a caracterização dos flavonoides quercetina-3-O-hexosídeo, quercetina-3-O-pentosídeo e quercetina-3-O-desoxihexosídeo. A formulação farmacêutica contendo o extrato ativo bruto de Marcetia macrophylla foi preparada e os testes físico-químicos (características organolépticas, análise de pH e centrifugação), o UVB in vitro (fator de proteção solar, FPS) e UVA (β-caroteno) foram investigados. A formulação apresentou resultados satisfatórios frente aos parâmetros físico-químicos avaliados e ativos contra UV. Assim, M. macrophylla apresentou atividades biológicas com potencial uso em preparações fitofarmacêuticas.
Assuntos
Antioxidantes/administração & dosagem , Extratos Vegetais/uso terapêutico , Melastomataceae/química , Protetores Solares/análiseRESUMO
The antioxidant, photoprotective and antinociceptive Marcetia macrophylla active extract was investigated as an active ingredient in a sunscreen cream formulation. Thus, the M. macrophylla extract showed IC50 of 3.43 mg/ml of the antioxidant (DPPH∙ scavenging test) and Sun Protection Factor of 20.25 (SPF/UV-B, at 250 µg/ml) and UV-A of 78.09% (photobleaching trans-resveratrol test). The antinociceptive activity was superior to all standards tested using the in vivo acetic acid-induced writhing test (99.14% at the dose of 200 mg/kg) and the high-performance liquid chromatography coupled with diode array detector and mass spectroscopy multi-stage (HPLC-DAD-MS/MS) enabled the structural characterization of the quercetin-3-O-hexoside, quercetin-3-O-pentoside and quercetin-3-O-desoxihexoside. The pharmaceutical formulation containing the Marcetia macrophylla crude active extract was prepared and the physicochemical tests (organoleptic characteristics, pH analysis and centrifugation), the in vitro UVB (sun protection factor, SPF) and UVA (β-carotene) using the spectroscopic method were investigated. The formulation showed satisfactory results concerning the physicochemical parameters evaluated and active against the UV test. Thus, M. macrophylla showed biological activities with potential use in pharmaceutical preparations.(AU)
O extrato bruto de Marcetia macrophylla mostrou atividade antioxidante, fotoprotetora e antinociceptiva, sendo em seguida investigado como ingrediente ativo em uma formulação fotoprotetora. Assim, o extrato de M. macrophylla apresentou atividade antioxidante com IC50 de 3,43 mg/mL (teste de sequestro do DPPH∙) e Fator de Proteção Solar de 20,25 (FPS/UV-B, 250 µg/mL) e UV-A de 78,09% (teste de fotobranqueamento do trans-resveratrol). A atividade antinociceptiva usando o teste in vivo de contorções abdominais induzidas por ácido acético foi superior a todos os padrões testados (99,14% na dose de 200 mg/Kg). A análise por cromatografia líquida de alta eficiência acoplada a detector de fotodiodos e espectroscopia de massas multi-estágio (CLAE-DAD-EM/EM) possibilitou a caracterização dos flavonoides quercetina-3-O-hexosídeo, quercetina-3-O-pentosídeo e quercetina-3-O-desoxihexosídeo. A formulação farmacêutica contendo o extrato ativo bruto de Marcetia macrophylla foi preparada e os testes físico-químicos (características organolépticas, análise de pH e centrifugação), o UVB in vitro (fator de proteção solar, FPS) e UVA (β-caroteno) foram investigados. A formulação apresentou resultados satisfatórios frente aos parâmetros físico-químicos avaliados e ativos contra UV. Assim, M. macrophylla apresentou atividades biológicas com potencial uso em preparações fitofarmacêuticas.(AU)
Assuntos
Melastomataceae/química , Protetores Solares/análise , Antioxidantes/administração & dosagem , Extratos Vegetais/uso terapêuticoRESUMO
Introducción: El Páramo es uno de los ecosistemas más afectados por actividades humanas, lo que aumenta la necesidad de estudios fenológicos como base para el manejo y la conservación. Objetivo: Describir la feno-morfología de Miconia ligustrina y Miconia elaeoides. Métodos: De septiembre 2019 a febrero 2020, y de abril 2021 hasta agosto del mismo año, se monitoreó la fenología de 12 individuos de cada especie. Adicionalmente, se vincularon datos fenológicos de ejemplares de herbario, para corroborar los resultados obtenidos. En los dos conjuntos de datos, se describió su distribución usando estadística circular, además, se obtuvieron registros de precipitación y temperatura del área. Adicionalmente, se describió la morfometría de cada especie. Resultados: El pico de floración de M. lingustrina es en abril, y la fructificación se concentra entre junio y julio; M. elaoides, florece de forma masiva en enero, con la máxima producción de frutos en mayo. Hubo correlación entre fenología y lluvias: la floración se da en época seca y la fructificación en la época lluviosa. Las especies difieren en morfología, pero, como en otras especies de Miconia, las flores y frutos son pequeños (aprox. 5 mm). Conclusión: La floración se presenta en la época seca y la fructificación en la época lluviosa, cuando las tasas de fotosíntesis son bajas y la frugivoría incrementa. Este patrón fenológico favorece la dispersión óptima de semillas.
Introduction: Paramos are among the ecosystems that are most affected by anthropic activities, increasing the need for phenological studies as a basis for management and conservation. Objective: To describe the pheno-morphology of Miconia ligustrina and Miconia elaeoides. Methods: From September 2019 to February 2020, and from April 2021 to August of the same year, the phenology of 12 individuals of each species was monitored. Additionally, phenological data of herbariums were linked to corroborate obtained results. In the two data sets, distribution of data was described using circular statistics; in addition, we recorded the precipitation and temperature in the area. Additionally, we described the morphometry of each species. Results: The flowering peak of M. ligustrina is in April, and fruiting concentrates between June and July; in M. elaeoides, flowering is massive in January, and the highest fruit production in May. The phenology was correlated with rainfall: flowering takes place in the dry season and fruiting in the rainy season. The species differ morphologically, but, as in other Miconia species, the flowers and fruits are small (approx. 5 mm). Conclusions: Flowering occurs in the dry season and fructification in the rainy season, when the photosynthetic rate is low and frugivory increases. This phenological pattern favors optimal seed dispersal.
Assuntos
Melastomataceae/crescimento & desenvolvimento , Myrtales/anatomia & histologia , Biologia , Colômbia , FloresRESUMO
Duchenne muscular dystrophy (DMD) is a severe disease with no cure caused by a genetic abnormality, promoting progressive muscle degeneration. Corticosteroids are used drugs in treatment associated with adverse effects. The extract of Miconia ferruginata (Melastomataceae) (MF) has demonstrated potent antioxidant and anti-inflammatory potential in vitro. This study used a DMD model (mdx) to determine the toxic dose of this plant and found a possible non-toxic dose with therapeutic effects. The mdx groups received an intraperitoneal injection of 0 (control group), 50, 100, 200, 300, and 2000 mg kg-1 of the aqueous leaf extract following a single-dose acute toxicity protocol and were observed for 14 days. The range of toxicity of the extract and LD50 were determined. Histopathological analysis, the quantification of fibrosis, and immunohistochemical analysis of the tissues were performed. The results demonstrated that 2000 mg kg-1 was highly toxic, inducing histopathological changes in the tissues evaluated, with 100% mortality in 48 hours. The other doses caused no behavioral changes or signs of toxicity. The MF extract led reduction in histopathological changes, fibrosis, and inflammation, a reduction in HSP70 and an increase in MCL-1 proteins. Doses of 50-200 mg kg-1 demonstrated regenerative tissue and anti-inflammatory potential.
Assuntos
Melastomataceae , Distrofia Muscular de Duchenne , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/metabolismo , Modelos Animais de Doenças , Fibrose , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/uso terapêutico , Extratos Vegetais/metabolismo , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidadeRESUMO
The plant Miconia albicans (Sw.) Triana has been popularly used in Brazil to treat chronic inflammatory disturbances, such as osteoarthritis. This disease affects 250 million people worldwide, and is associated with intense pain and loss of articular function. There is a lack of information about the phytochemistry and bioactivity of M. albicans. Therefore, this study determined the chemical composition of some extracts and evaluated their cytotoxicity, along with their antioxidant and anti-inflammatory, activities using in vitro models. Aqueous and ethanolic extracts were prepared. Afterwards, a liquid-liquid partition was developed using chloroform, ethyl acetate, and n-butanol. The extracts were characterized by LC-MS, and their biological activities were evaluated on epithelial cells (Vero), tumoral hepatic cells (Hep-G2), and THP-1 macrophages. LC-MS analyses identified several flavonoids in all fractions, such as quercetin, myricetin, and their glycosides. The crude extracts and n-butanol fractions did not present cytotoxicity to the cells. The non-toxic fractions presented significant antioxidant activity when evaluated in terms of DPPH scavenging activity, lipid peroxidation, and ROS inhibition. THP-1 macrophages treated with the n-butanol fraction (250 µg/mL) released fewer pro-inflammatory cytokines, even in the presence of LPS. In the future, it will be necessary to identify the phytochemicals that are responsible for anti-inflammatory effects for the discovery of new drugs. In vivo studies on M. albicans extracts are still required to confirm their possible mechanisms of action.
Assuntos
Melastomataceae , 1-Butanol , Anti-Inflamatórios/química , Antioxidantes/química , Clorofórmio , Citocinas , Flavonoides/farmacologia , Glicosídeos , Humanos , Lipopolissacarídeos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Quercetina/farmacologia , Espécies Reativas de OxigênioRESUMO
Stingless bees are effective pollinators of native tropical flora. Their environmental service maintains flow of pollen through pollination, increase reproductive success and influence genetic structure in plants. The management of stingless bees "meliponiculture", is an activity limited to the countryside in Ecuador. The lack of knowledge of their managers about pollen resources can affect the correct maintenance/production of nests. The objective is to identify botanical families and genera of pollen grains collected by stingless bees by morphological features and differentiate potential species using geometric morphometry. Thirty-six pot pollen samples were collected from three Ecuadorian provinces located in two climatically different zones. Pollen type identification was based on the Number, Position, Character system. Using morphological features, the families and genera were established. Morphometry landmarks were used to show variation for species differentiation. Abundance, diversity, similarity and dominance indices were established by counting pollen grains, as well as spatial distribution relationships by means of Poisson regression. Forty-six pollen types were determined in two study areas, classified into 27 families and 18 genera. In addition, it was possible to identify more than one species, classified within the same family and genus, thanks to morphometric analysis. 1148 ± 799 (max 4211; min 29) pollen grains were counting in average. The diversity showed a high richness, low dominance and similarity between pollen resources. Families Melastomataceae and Asteraceae, genera Miconia and Bidens, were found as the main pollen resources. The stingless bee of this study are mostly generalist as shown the interaction network. The results of the present survey showed that stingless bees do not collect pollen from a single species, although there is evidence of a predilection for certain plant families. The diversity indexes showed high richness but low uniformity in the abundance of each family identified. The results of the study are also meaningful to the meliponiculture sector as there is a need to improve management practices to preserve the biodiversity and the environment.
Assuntos
Melastomataceae , Pólen , Animais , Abelhas , Equador , Microscopia Eletrônica de Varredura , Plantas , PolinizaçãoRESUMO
Weeds pose a problem, infesting areas and imposing competition and harvesting difficulties in agricultural systems. Studies that provide the use of alternative methods for weed control, in order to minimize negative impacts on the environment, have intensified. Native flora represents a source of unexplored metabolites with multiple applications, such as bioherbicides. Therefore, we aimed to carry out a preliminary phytochemical analysis of crude extracts and fractions of Miconia auricoma and M. ligustroides and to evaluate these and the isolated metabolites phytotoxicity on the growth of the target species. The growth bioassays were conducted with Petri dishes with lettuce, morning glory, and sourgrass seeds incubated in germination chambers. Phytochemical analysis revealed the presence of flavonoids, isolated myricetin, and a mixture of quercetin and myricetin. The results showed that seedling growth was affected in a dose-dependent manner, with the root most affected and the seedlings of the lettuce, morning glory, and sourgrass as the most sensitive species, respectively. Chloroform fractions and myricetin were the most inhibitory bioassays evaluated. The seedlings showed structural changes, such as yellowing, nonexpanded cotyledons, and less branched roots. These results indicate the phytotoxic potential of Miconia allelochemicals, since there was the appearance of abnormal seedlings and growth reduction.
Assuntos
Melastomataceae , Germinação , Lactuca , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Daninhas , Plântula , Controle de Plantas DaninhasRESUMO
The androecium of Melastomataceae presents notable modifications in its merosity, morphology between whorls and in prolonged connectives and appendages. We carried out a comparative study of six Melastomataceae species to shed light on the developmental processes that originate such stamen diversity. The development of stamens was studied using scanning electron microscopy and histological observations. The stamens of all species studied have a curved shape because they emerge on a plane displaced by the perigynous hypanthium. They are the last flower organs to initiate and therefore their growth is inwards and towards the floral center. Despite the temporal inversion between carpels and stamens in Melastomataceae, the androecium maintains the centripetal pattern of development, the antepetalous stamens emerging after antesepalous stamens. The isomerous androecium can be the result of abortion of the antepetalous stamens, whereas heterostemony seems to be caused by differences in position and the stamen development time. Pedoconnectives and ventral appendages originate from the basal expansion of the anther late in floral development. The delay in stamen development may be a consequence of their dependence on the formation of a previous space so that they can grow. Most of the stamen diversity is explained by the formation of the connectives and their appendages. The formation of a basal-ventral anther prolongation, which culminates in the development of the pedoconnective, does not differ from other types of sectorial growth of the connective, which form shorter structures.
Assuntos
Melastomataceae , Flores/anatomia & histologia , Melastomataceae/anatomia & histologia , Microscopia Eletrônica de VarreduraRESUMO
Berries come from hundreds of different species of plants spread around the world. Blackberries, blueberries and raspberries, for instance, are popular berries that have attracted attention for providing several benefits to human health. Wild berries from the Melastomataceae family are commonly encountered in the Amazon, although these small blue fruits are poorly consumed. Although domesticated fruits give better monetary profits, the consumption of wild fruits is a desirable option to afford income and/or food to communities at the same time as keep the Amazon region preserved. Aiming the divulgation of the nutritional potential of these plants, this paper describes the study of six species of Amazonian blueberries, five of them from the Clidemia genus and one from the Tococa genus, in regard to their nutritional and chemical composition and antioxidant activity (AA). The levels of moisture, ash, protein, lipids, carbohydrates, and the total caloric values obtained for the Amazonian blueberries were comparable to other common edible berries. Although the six species are similar in terms of nutritional composition, their anthocyanin profiles and contents are quite peculiar. Two non-methylated anthocyanins, cyanidin and delphinidin, which bound to a variable number of sugars, characterized the berries of the genera Clidemia and Tococa. Clidemia japurensis, Clidemia hirta and Tococa bullifera were rich in tri-glycosylated anthocyanins, although differences are notable between them. Clidemia pustulata and Clidemia capitellata were characterized by the prevalence of mono-glycosylated anthocyanins, and Clidemia rubra showed a unique profile with mono- and di-glycosylated homologous as the main anthocyanins. In addition to their different chemical profiles, the concentrations of anthocyanins and other phenolic compounds varied a lot among the six species studied. The species C. rubra had the highest total concentration of phenolic acids and flavonoids. Therefore, this study showed that the blueberries analyzed have potential to be better explored, which we suggest doing in a sustainable way, aiming at the preservation of the Amazon's biodiversity.
Assuntos
Mirtilos Azuis (Planta) , Melastomataceae , Antocianinas/química , Antioxidantes/química , Mirtilos Azuis (Planta)/química , Humanos , Fenóis/químicaRESUMO
Species of the genus Miconia are used in traditional medicine for the treatment of diseases, such as pain, throat infections, fever, and cold, and they used as depuratives, diuretics, and sedatives. This work reviewed studies carried out with Miconia species, highlighting its ethnomedicinal uses and pharmacological and phytochemical potential. This information was collected in the main platforms of scientific research (PubMed, Scopus, and Web of Science). Our findings show that some of the traditional uses of Miconia are corroborated by biological and/or pharmacological assays, which demonstrated, among other properties, anti-inflammatory, analgesic, antimutagenic, antiparasitic, antioxidant, cytotoxic, and antimicrobial activities. A total of 148 chemical compounds were identified in Miconia species, with phenolic compounds being the main constituents found in the species of this genus. Such phytochemical investigations have demonstrated the potential of species belonging to this genus as a source of bioactive substances, thus reinforcing their medicinal and pharmacological importance.