RESUMO
Trema, a genus of the popularly known Cannabaceae, has recently been the subject of cannabinoid bioprospection. T. micrantha is a tree with pharmacological potential widely used in folk medicine. It has two types of glandular trichomes, bulbous and filiform, spread throughout the plant body. Considering the proximity of this species to Cannabis sativa and Trema orientalis, species containing cannabinoids, the glandular trichomes of T. micrantha are also expected to be related to the secretion of these compounds. Thus, this study aims to detail the morphology of secretory trichomes during the synthesis, storing and release of metabolites in T. micrantha. We tested the proposition that they could be a putative type of cannabinoid-secreting gland. Pistillate and staminate flowers and leaves were collected and processed for ontogenic, histochemical, and ultrastructural analyses. Both types of glandular trichomes originate from a protodermal cell. They are putative cannabinoid-secreting sites because: (1) terpene-phenols and, more specifically, cannabinoids were detected in situ; (2) their secretory subcellular apparatus is consistent with that found in C. sativa: modified plastids, polyribosomes, an extensive rough endoplasmic reticulum, and a moniliform smooth endoplasmic reticulum. Plastids and smooth endoplasmic reticulum are involved in the synthesis of terpenes, while the rough endoplasmic reticulum acts in the phenolic synthesis. These substances cross the plasma membrane by exocytosis and are released outside the trichome through cuticle pores. The study of the cell biology of the putative cannabinoid glands can promote the advancement of prospecting for natural products in plants.
Assuntos
Cannabaceae , Canabinoides , Cannabis , Trema , Canabinoides/análise , Canabinoides/química , Canabinoides/metabolismo , Trema/metabolismo , Tricomas/ultraestrutura , Cannabis/metabolismo , Terpenos/química , Folhas de Planta/metabolismoRESUMO
The presence of mucilage cells in plants, studied mainly in vegetative organs, is a condition shared by several taxonomic groups and aspects related to their diversity have been discussed with systematic purposes. This study explores the flower distribution and classification of mucilage cells in Rosales species, with inferences about flower functions. Floral buds from fifty-seven species representing seven of nine families recognized in the Rosales were sampled and processed for light and transmission electron microscopy. Mucilage cells were found in about 40% of the studied species of Cannabaceae, Rhamnaceae, Ulmaceae, and Urticaceae families, whereas no floral mucilage cells were found in species of Elaeagnaceae, Moraceae, and Rosaceae. Mucilage cells were found in the epidermis and internal tissues of many organs of different floral morph types. There is a great diversity of forms of presentation of mucilage in cells, from smaller individualized single cells to very bulky cells and to completely filled mucilage reservoirs. In some cases, cells with mucilage apparently in the cell wall and others with mucilage in the vacuole seem to occur side by side. This diversity challenges the existing classifications of mucilage cells and reinforces the importance of ontogenetic and ultrastructural studies following the path of mucilage in cells in order to propose a more natural classification and to elucidate the evolution of mucilage cells in plants.
Assuntos
Cannabaceae , Mucilagem Vegetal , Rosales , Humanos , Flores/ultraestrutura , Polissacarídeos , Microscopia Eletrônica de TransmissãoRESUMO
Hop (Humulus lupulus L.) female inflorescences are important raw materials used to produce beers, cosmetics, and medicines. Vegetative propagation is the preferred way of obtaining seedlings for commercial cultivations as female plants produce more lupulin than male plants, a component of commercial interest. It can be carried out by macropropagation (stem cuttings or rhizomes) or micropropagation. This review aimed to systematize different techniques of hop vegetative propagation, with no time frame, from searches in the main academic research bases: Capes Journal Portal, Scielo, Scopus, Web of Science, Science Direct, Google Scholar, and ResearchGate. Most studies are related to micropropagation, mainly addressing different plant regulators and concentrations, as well as types of explants and culture media, strategies to produce virus-free plants, artificial lighting, and cryopreservation. Experiments with stem cuttings are more common regarding macropropagation, but factors such as size and origin of cuttings, rooting period, and the response of different cultivars need to be better evaluated. Cultivation by cuttings allows the production of clones of female plants and micropropagation the production of virus-free clones in a short time and less physical space. Currently, micropropagation has been widely applied to cryopreservation.(AU)
As inflorescências femininas do lúpulo (Humulus lupulus L.) são matérias-primas importantes utilizadas na produção de cervejas, cosméticos e medicamentos. Como as plantas femininas produzem mais lupulina que as masculinas, componente de interesse comercial, a propagação vegetativa é a forma preferencial de obtenção de mudas para os cultivos comerciais. Esta pode ser realizada por macropropagação (estaquia caulinar ou rizomas) ou micropropagação. O objetivo desta revisão foi sistematizar as diferentes técnicas de propagação vegetativa do lúpulo, sem recorte temporal, a partir de buscas nas principais bases de pesquisa acadêmica: Portal de Periódicos Capes, Scielo, Scopus, Web of Science, Science Direct, Google Acadêmico e Research Gate. A maioria dos trabalhos são relacionados à micropropagação, abordando principalmente diferentes reguladores vegetais e concentrações, além de tipos de explantes e meios de cultura, estratégias para produzir plantas livres de vírus, iluminação artificial e criopreservação. Quanto à macropropagação, experimentos com estaquia caulinar são mais comuns, porém fatores precisam ser melhor avaliados tais como tamanho e origem das estacas, período de enraizamento e resposta de diferentes cultivares. O cultivo por estacas permite a produção de clones de plantas femininas e a micropropagação a produção de clones isentos de vírus, em pouco tempo e em menor espaço físico. Atualmente, a micropropagação tem sido muito aplicada à criopreservação.(AU)
Assuntos
Humulus/crescimento & desenvolvimento , Rizoma , Inflorescência , Cannabaceae/crescimento & desenvolvimento , HistóriaRESUMO
PREMISE: Celtis is the most species-rich genus of Cannabaceae, an economically important family. Celtis species have been described as wind-pollinated and andromonoecious. However, the andromonoecy of Celtis has been debated because there are reports of monoclinous flowers with non-opening anthers on short filaments. Our objective was to study the floral morphogenesis of Celtis to establish the breeding system and to better understand the developmental patterns that lead to the formation of reduced flowers in the genus. METHODS: Flowers and floral buds of Celtis species were studied using scanning electron microscopy, high-resolution x-ray computed tomography, and light microscopy. RESULTS: All flowers initiate stamens and carpels during early floral development, but either stamens or carpels abort during later stages. Thus, at anthesis, flowers are either functionally pistillate or functionally staminate. In pistillate flowers, stamens abort late and become staminodes with normal-looking anthers. These anthers have no functional endothecium and, in most of the species studied, produce no viable pollen grains. The gynoecium is pseudomonomerous, and its vascularization is similar in the sampled species. In staminate flowers, the gynoecium aborts early resulting in small pistillodes. No vestiges of petals were found. CONCLUSIONS: The species studied are monoecious and not andromonoecious as described earlier. The absence of petals, the carpel and stamen abortion, and the pseudomonomerous gynoecium result in the reduced flowers of Celtis species. The use of high-resolution x-ray computed tomography was essential for a more accurate interpretation of ovary vascularization, confirming the pseudomonomerous structure of the gynoecium.
Assuntos
Cannabaceae , Ulmaceae , Flores , Morfogênese , Melhoramento VegetalRESUMO
Every organism on Earth must cope with a multitude of species interactions both directly and indirectly throughout its life cycle. However, how selection from multiple species occupying different trophic levels affects diffuse mutualisms has received little attention. As a result, how a given species amalgamates the combined effects of selection from multiple mutualists and antagonists to enhance its own fitness remains little understood. We investigated how multispecies interactions (frugivorous birds, ants, fruit flies and parasitoid wasps) generate selection on fruit traits in a seed dispersal mutualism. We used structural equation models to assess whether seed dispersers (frugivorous birds and ants) exerted phenotypic selection on fruit and seed traits in the spiny hackberry (Celtis ehrenbergiana), a fleshy-fruited tree, and how these selection regimes were influenced by fruit fly infestation and wasp parasitoidism levels. Birds exerted negative correlational selection on the combination of fruit crop size and mean seed weight, favouring either large crops with small seeds or small crops with large seeds. Parasitoids selected plants with higher fruit fly infestation levels, and fruit flies exerted positive directional selection on fruit size, which was positively correlated with seed weight. Therefore, higher parasitoidism indirectly correlated with higher plant fitness through increased bird fruit removal. In addition, ants exerted negative directional selection on mean seed weight. Our results show that strong selection on phenotypic traits may still arise in perceived diffuse species interactions. Overall, we emphasize the need to consider diverse direct and indirect partners to achieve a better understanding of the mechanisms driving phenotypic trait evolution in multispecies interactions.
Assuntos
Frutas/genética , Dispersão de Sementes , Sementes/genética , Seleção Genética , Ulmaceae/genética , Animais , Evolução Biológica , Aves , Cannabaceae/genética , Cadeia Alimentar , Interações Hospedeiro-Parasita , InsetosRESUMO
Cannabaceae is a known family because of the production of cannabinoids in laticifers and glandular trichomes of Cannabis sativa. Laticifers are latex-secreting structures, which in Cannabaceae were identified only in C. sativa and Humulus lupulus. This study aimed to expand the knowledge of laticifers in Cannabaceae by checking their structural type and distribution, and the main classes of substances in the latex of Celtis pubescens, Pteroceltis tatarinowii, and Trema micrantha. Such information is also updated for C. sativa. Samples of shoot apices, stems, leaves, and flowers were processed for anatomical, histochemical, ultrastructural, and cytochemical analyses. Laticifers are articulated unbranched in all species instead of non-articulated as previously described for the family. They occur in all sampled organs. They are thick-walled, multinucleate, with a large vacuole and a peripheral cytoplasm. The cytoplasm is rich in mitochondria, endoplasmic reticulum, dictyosomes, ribosomes, and plastids containing starch grains and oil drops. Pectinase and cellulase activities were detected in the laticifer wall and vacuole, confirming its articulated origin, described by first time in the family. These enzymes promote the complete dissolution of the laticifer terminal walls. The latex contains proteins, lipids, and polysaccharides in addition to phenolics (C. sativa) and terpenes (C. pubescens, T. micrantha). The presence of laticifers with similar distribution and morphology supports the recent insertion of Celtis, Pteroceltis, and Trema in Cannabaceae. The articulated type of laticifer found in Cannabaceae, Moraceae, and Urticaceae indicates that the separation of these families by having distinct laticifer types should be reviewed.
Assuntos
Cannabaceae/química , Látex/química , Folhas de Planta/químicaRESUMO
PREMISE OF THE STUDY: This study details the unusual synorganization of the staminate flower in wind-pollinated urticalean rosids to add the missing pieces that complete the puzzle of the explosive mechanism of pollen release in this group. METHODS: Flower buds and flowers were analyzed using light and scanning electron microscopy. KEY RESULTS: The pistillode, stamens, and sepals form a floral apparatus that explosively releases pollen to be carried by the wind. The anthers dehisce when the stamens are still inflexed on the floral bud and are enveloped by the sepals and supported by an inflated pistillode. The distension of the filaments presses the pistillode, which decreases the pressure exerted on the anthers by releasing the air accumulated internally through its apical orifice. The extended filaments and the dehiscent free anthers move rapidly outward from the center of the flower. This movement of the filaments is then blocked by the robust basally united sepals, which causes a rapid inversion of the anther position, thus hurling the pollen grains far from the flower. The pollen grains are released grouped by the mucilage produced in high quantity in the cells found in all floral organs. CONCLUSIONS: The anatomical structure of the pistillode and the finding of mucilaginous cells are the main features that help in the understanding the explosive mechanism of pollen release in urticalean rosids. The pistillode can be considered an exaptation because it was evolved later to provide a new role in the plant, optimizing male fitness.
Assuntos
Cannabaceae/anatomia & histologia , Flores/anatomia & histologia , Moraceae/anatomia & histologia , Polinização , Urticaceae/anatomia & histologia , Cannabaceae/fisiologia , Flores/fisiologia , Moraceae/fisiologia , Urticaceae/fisiologia , VentoRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Celtis pallida Torr (Cannabaceae) is employed as a folk medicine for the treatment of inflammation, pain, skin infections, and diarrhea, among other diseases. AIM OF THE STUDY: The purpose of this work was to assess the chemical composition, the in vitro and in vivo toxicity, the antimicrobial, anti-inflammatory, antidiarrheal, antinociceptive, locomotor, and sedative effects of an ethanolic extract obtained from Celtis pallida aerial parts (CPE). MATERIALS AND METHODS: The composition of CPE was carried out by GC-MS. The in vitro and in vivo toxic activity of CPE was estimated with the comet assay (10-1000⯵g/ml) for 5â¯h in peripheral blood mononuclear cells, and the acute toxicity test (500-5000â¯mg/kg p.o.), for 14 days, respectively. The antimicrobial effect of CPE was evaluated using the minimum inhibitory concentration (MIC) assay, whereas the antidiarrheal activity (10-200â¯mg/kg p.o.) was calculated using the castor oil test. The antinociceptive effects of CPE (50-200â¯mg/kg p.o.) were estimated with the acetic acid and formalin tests, as well as the hot plate test. The sedative and locomotor activities of CPE (50-200â¯mg/kg p.o.) were assessed with the pentobarbital-induced sleeping time test and the rotarod test, respectively. RESULTS: The main compound found in CPE was the triterpene ursolic acid (22% of the extract). CPE at concentrations of 100⯵g/ml or higher induced genotoxicity in vitro and showed low in vivo toxicity (LD50 > 5000â¯mg/kg p.o.). Additionally, CPE lacked (MIC > 400⯵g/ml) antimicrobial activity but exerts antinociceptive (ED50 = 12.5⯱â¯1.5â¯mg/kg) and antidiarrheal effects (ED50 = 2.8â¯mg/kg), without inducing sedative effects or altering the locomotor activity. The antinociceptive activity of CPE suggests the participation of adrenoceptors, as well as the nitric oxide/cyclic guanosine monophosphate (cGMP) pathway. CONCLUSION: C. pallida exerts its antinociceptive effects probably mediated by the nitric oxide/cyclic guanosine monophosphate (cGMP) pathway.
Assuntos
Analgésicos/farmacologia , Cannabaceae , Medição da Dor/efeitos dos fármacos , Componentes Aéreos da Planta , Extratos Vegetais/farmacologia , Analgésicos/isolamento & purificação , Analgésicos/toxicidade , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/toxicidade , Antidiarreicos/isolamento & purificação , Antidiarreicos/farmacologia , Antidiarreicos/toxicidade , Relação Dose-Resposta a Droga , Etanol/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Mutagenicidade/métodos , Medição da Dor/métodos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , UlmaceaeRESUMO
RESUMO Celtis iguanaea (Jacq.) Sargent is popularly used to treat urinary infections, kidneys, breast, body aches, rheumatism, asthma, cramps, poor digestion and as a diuretic medicine. This study aims to determine the acute toxicity of the aqueous leaf extract of Celtis iguanaea (Jacq.) Sargent in rodents. After the collection processes, identification, drying and grinding, the lyophilized powder of the leaves produced, by infusion, the aqueous extract and it was dissolved in saline 0.9%. The administration was made by gavage at a dose of 2000 mg kg-1to rats and mice of both genders. The oral toxicity was determined according to the OECD 423 guide. Signs of toxicity were observed for 15 days and classified from 0 to 4 respectively as missing, rare, mild, moderate and severe. The weight of the animals and the physiological parameters such as food intake and excrements production were observed. All animal tissue samples were collected for histological analysis. The extract was included in Type 5 (substance with LD50 higher than 2000 mg kg-1 and less than 5000 mg kg-1), being considered of low toxicity, but the histopathologycal findings suggested nephrotoxicity and cardiotoxicity. The absolute weight of the kidneys and the heart of the male rats and mice increased, but there was no significant raise in the relative weight of the animals’ organs.
RESUMO Celtis iguanaea (Jacq.) Sargent é uma planta usada popularmente para tratar infecções do trato urinário, rim, mama, dores no corpo, reumatismo, asma, cólicas, má digestão e também é usada como diurético. Este trabalho objetivou determinar a toxicidade aguda do extrato aquoso de folhas de Celtis iguanaea (Jacq.) Sargent em roedores. Após os processos de coleta, identificação, secagem e moagem, o pó liofilizado das folhas da planta foi utilizado para produzir o seu extrato aquoso por infusão e então dissolvido em solução salina a 0.9 %. A administração foi feita por gavagem na dose de 2000 mg kg-1 em ratos e camundongos de ambos os sexos. A toxicidade oral foi determinada de acordo com o guia 423 da OECD. Sinais de toxicidade foram observados por 15 dias e tabulados de 0 a 4, respectivamente, como ausentes, raros, leves, moderados e graves. Foi acompanhado o peso dos animais e parâmetros fisiológicos tais como alimentação e excreções. Amostras do tecido de todo o animal foram coletadas para análise histológica. A toxicidade encontrada para o extrato foi incluída na classe 5 (substâncias com DL50 superior a 2000 mg kg-1 e menor que 5000 mg kg-1) sendo considerada baixa, porém, as observações histopatológicas sugerem nefrotoxicidade e cardiotoxicidade. O peso absoluto dos rins e coração de ratos e camundongos machos aumentou, porém, não houve aumento significativo no peso relativo dos órgãos dos animais.