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1.
BMC Plant Biol ; 22(1): 15, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983403

RESUMO

BACKGROUND: Cremastra appendiculata is a rare terrestrial orchid with a high market value as an ornamental and medicinal plant. However, the species depends entirely on fungi for seed germination under natural conditions. In a previous study, we have successfully isolated and identified the mycorrhizal fungus Coprinellus disseminatus which was able to induce the germination of C. appendiculata seeds. We then speculated that C. disseminatus may do so by breaking the testa imposed dormancy of the seeds. In this study, biochemical and transcriptomic analyses were used to characterize the germination of C. appendiculata seeds, collected at different stages of germination, as affected by C. disseminatus. RESULTS: The lignocellulose in the seeds coat of C. appendiculata was degraded by the mycorrhizal fungus resulting in facilitated absorption of water. The rate of decline in lignin content was 67 and 73% at 6 and 12 days after sowing, respectively. The water content increased from 13 to 90% during symbiosis. A total of 15,382 genes showing significantly different levels of expression (log2 FPKM≥2.0, Qvalue≤0.05) were successfully identified among all libraries, where the highest number of DEGs was shared between 6 days versus 0 day after symbiotic germination. Gene annotation results suggested that 15 key genes related water-status, such as DHN gene family and Xero 1 were down-regulated. The genes zeaxanthin epoxidase ZEP, 9-cis-epoxycarotenoid dioxygenase NCED3 and ß-carotene hydroxylase involved in the biosynthesis of abscisic acid (ABA) were significantly down-regulated in 6 days as compared to 0 day after symbiotic germination. CONCLUSIONS: This work demonstrates that mycorrhizal fungus C. disseminatus can stimulate C. appendiculata seeds germination through a mechanism of breaking the testa imposed dormancy and inducing water absorption of the embryo.


Assuntos
Agaricales/fisiologia , Micorrizas/fisiologia , Orchidaceae/fisiologia , Simbiose , Agaricales/genética , Agaricales/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Perfilação da Expressão Gênica , Genes de Plantas , Germinação , Lignina/metabolismo , Anotação de Sequência Molecular , Orchidaceae/crescimento & desenvolvimento , Orchidaceae/microbiologia , RNA-Seq , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Água/metabolismo
2.
Phytochemistry ; 195: 113059, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34933209

RESUMO

Bletilla striata is a precious traditional Chinese medical herb with a wide range of applications in pharmacological and cosmetic fields. Because of the shortage of resources, Bletilla ochracea and Bletilla formosanare are also used as the substitutes. To distinguish the differences and homologies, the typical morphologic and microscopic characteristics of them were compared, and a UPLC fingerprint analysis coupled with chemometric methods were developed for characterization and quality evaluation of Bletillae Rhizoma. Gastrodin, protocatechuic acid, gymnoside V, blestrianol A, coelonin, gymnosides Ⅸ and batatasin II were identified as the potential chemical markers for comprehensive quality evaluation by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The anti-melanogenic activities of the three species were also compared for the first time in vivo using the zebrafish model, the results suggested that B. striata and its two substitutes had obvious anti-melanogenic activities, and they were not-toxic at depigmenting doses. Molecular docking studies revealed batatasin III, blestrianol A, coelonin, and gastrodin were possible multitarget compounds associated with melanogenesis suppression, which are important for their potential future medical application.


Assuntos
Melaninas , Orchidaceae , Animais , Simulação de Acoplamento Molecular , Rizoma , Peixe-Zebra
3.
New Phytol ; 233(1): 52-61, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34460949

RESUMO

Plant-pollinator interactions provide a natural experiment in signal evolution. Flowers are known to have evolved colour signals that maximise their ease of detection by the visual systems of important pollinators such as bees. Whilst most angiosperms are bee pollinated, our understanding on how the second largest group of pollinating insects, flies, may influence flower colour evolution is limited to the use of categorical models of colour discrimination that do not reflect the small colour differences commonly observed between and within flower species. Here we show by comparing flower signals that occur in different environments including total absence of bees, a mixture of bee and fly pollination within one plant family (Orchidaceae) from a single community, and typical flowers from a broad taxonomic sampling of the same geographic region, that perceptually different colours, empirically measured, do evolve in response to different types of insect pollinators. We show evidence of both convergence among fly-pollinated floral colours but also of divergence and displacement of colour signals in the absence of bee pollinators. Our findings give an insight into how both ecological and agricultural systems may be affected by changes in pollinator distributions around the world.


Assuntos
Dípteros , Orchidaceae , Animais , Abelhas , Cor , Flores , Polinização
4.
New Phytol ; 233(1): 145-155, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34614215

RESUMO

Viruses cause severe damage on crops, and identification of key gene(s) that can comprehensively activate antiviral immunity will provide insights for designing effective antiviral strategies. Salicylic acid (SA)-mediated antiviral immunity and RNA interference (RNAi) are two independently discovered antiviral pathways. Previously, we identified the orchid stress-associated protein (SAP), Pha13, which serves as a hub in SA-mediated antiviral immunity. As SAPs exist as a protein family, whether duplicated SAPs have redundant or distinctive functions in antiviral immunity remains elusive. We performed functional assays on orchid Pha21, a homolog of Pha13, using transient and transgenic approaches on orchid, Arabidopsis and Nicotiana benthamiana to overexpress and/or silence Pha21. The SA treatment induced the expression of both Pha13 and Pha21, whereas Pha21 was found to play a key role in the initiation of the RNAi pathway in Phalaenopsis orchids. We demonstrated that Pha21-mediated antiviral immunity and enhancement of the RNAi pathway is conserved between dicotyledons and monocotyledons. We provide new insight that orchid SAPs confer distinctive functions to coordinate both SA-signaling and RNAi for comprehensive activation of antiviral immunity, and this information will help us develop antiviral strategies on crops.


Assuntos
Arabidopsis , Orchidaceae , Antivirais , Arabidopsis/genética , Proteínas de Choque Térmico , Orchidaceae/genética , Ácido Salicílico
5.
Plant Biol (Stuttg) ; 24(1): 157-167, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34724285

RESUMO

Pollination of the pantropical Vanilla has been linked to melittophily and food deception. Here we investigated the role of flower traits on the reproduction of Neotropical Vanilla. We also studied the evolution of pollination systems in order to understand the origin of production of flower resources and the diversification of pollinators in this orchid genus. Our study was founded on data of adaptations in flower morphology, production of resources, scent release, pollinators and breeding systems of Vanilla and presenting new data on reproductive biology of V. palmarum. Data on reproductive biology of Vanilla were mapped onto a phylogeny to address our queries on the evolution of pollination systems in this genus. Vanilla palmarum shows a mixed mating system, with its facultative autogamous flowers being pollinated by hummingbirds. Its yellow flowers are scentless and produces nectar. Mapping of the pollination system onto trees resulted in one origin for bird pollination and at least two origins for autogamy in Vanilla. Nectar secretion has a single origin in the Neotropical thick-leafed lineage. Bird pollination of Vanilla is shown for the first time. The origin of ornithophily within a bee-pollinated clade is supported by flower morphology. Floral transitions to ornithophily have been favoured by the occupation of a distinct niche from that of the other thick-leafed Vanilla species. Despite its specialized pollination, V. palmarum is autogamous. A mixed mating system can promote reproductive assurance in the case of a decline in pollinator populations, or in areas where pollinator services are irregular or absent.


Assuntos
Orchidaceae , Vanilla , Animais , Abelhas , Flores , Melhoramento Vegetal , Néctar de Plantas , Polinização
6.
Plant Biol (Stuttg) ; 24(1): 168-175, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34724312

RESUMO

Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orchid from Indonesia (Dendrobium strebloceras), and four temperate species from New Zealand, D. cunninghamii (epiphytic), and Gastrodia cunninghamii, Pterostylis banksii and Thelymitra nervosa (terrestrial). Seeds were aged under controlled laboratory conditions (3-month storage at 60% RH and 20 °C). Seed viability was tested before and after ageing using tetrazolium chloride staining. Fatty acid methyl esters from fresh and aged seeds were extracted through trans-esterification, and then analysed using gas chromatography-mass spectrometry. All species had high initial viability (>80%) and experienced significant viability loss after ageing. The saturated, polyunsaturated, monounsaturated and total fatty acid content decreased with ageing in all species, but this reduction was only significant for D. strebloceras, D. cunninghamii and G. cunninghamii. Our results suggest that fatty acid degradation is a typical response to ageing in orchids, albeit with species variation in magnitude, but the link between fatty acid degradation and viability was not elucidated. Pterostylis banksii exemplified this variation; it showed marked viability loss despite not having a significant reduction in its fatty acid content after ageing. More research is required to identify the effect of ageing on fatty acid composition in orchids, and its contribution to seed viability loss.


Assuntos
Ácidos Graxos , Orchidaceae , Cromatografia Gasosa-Espectrometria de Massas , Sementes
7.
Plant Biol (Stuttg) ; 24(1): 145-156, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34490731

RESUMO

Most species in the genus Cypripedium (Cypripedioideae) produce trap flowers, making it a model lineage to study deceptive pollination. Floral attractants in most species studied appear to target bee species of different sizes. However, more recent publications report fly pollination in some subalpine species, suggesting novel suites of adaptive floral traits. Cypripedium lichiangense (section Trigonopedia) is an endangered subalpine species endemic to the Hengduan Mountains, China. We observed and analysed its floral traits, pollinators and breeding systems over 2 years in situ and in the lab. Cypripedium lichiangense was visited by females of Ferdinandea cuprea (Syrphidae). The pollinia were carried dorsally on the fly thoraces. The eggs of this fly were frequently found in the saccate labellum and on other floral organs, suggesting brood-site mimesis. The orchid is self-compatible, but cross-pollination produces more viable embryos. We propose a new mode of floral mimesis, humus-rich oviposition site mimicry, for C. lichiangense. Compared with the mimesis of aphid colonies attracting syrphid pollinators (subfamily Syrphinae), whose larvae are entomophagic, as reported in some Paphiopedilum species (Cypripedioideae), pollination by deceit in C. lichiangense represents a distinct and separate mode of exploitation of another saprophagic (or phytophagic) larvae syrphid lineage in the subfamily Eristalinae and appears to indicate diversity of pollination strategies in Section Trigonopedia of Cypripedium. However, this new brood-site mimesis seems to be less attractive to pollinators. As a possible adaptation to the weak attracted pollination strategy, this plant species has a long flowering period and extended lifespan of individual flowers to ensure reproductive success.


Assuntos
Orchidaceae , Animais , Abelhas , Flores , Oviposição , Polinização , Solo
8.
BMC Plant Biol ; 21(1): 504, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724893

RESUMO

BACKGROUND: Bletilla striata is one of the important species belonging to the Bletilla genus of Orchidaceae. Since its extracts have an astringent effect on human tissues, B. striata is widely used for hemostasis and healing. Recently, some other beneficial effects have also been uncovered, such as antioxidation, antiinflammation, antifibrotic, and immunomodulatory activities. As a key step towards a thorough understanding on the medicinal ingredient production in B. striata, deciphering the regulatory codes of the metabolic pathways becomes a major task. RESULTS: In this study, three organs (roots, tubers and leaves) of B. striata were analyzed by integrating transcriptome sequencing and untargeted metabolic profiling data. Five different metabolic pathways, involved in polysaccharide, sterol, flavonoid, terpenoid and alkaloid biosynthesis, were investigated respectively. For each pathway, the expression patterns of the enzyme-coding genes and the accumulation levels of the metabolic intermediates were presented in an organ-specific way. Furthermore, the relationships between enzyme activities and the levels of the related metabolites were partially inferred. Within the biosynthetic pathways of polysaccharides and flavonoids, long-range phytochemical transportation was proposed for certain metabolic intermediates and/or the enzymes. CONCLUSIONS: The data presented by this work could strengthen the molecular basis for further studies on breeding and medicinal uses of B. striata.


Assuntos
Redes e Vias Metabólicas/genética , Orchidaceae/química , Orchidaceae/genética , Orchidaceae/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/química , Raízes de Plantas/química , Tubérculos/química , China , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Plantas Medicinais/química , Plantas Medicinais/genética , Plantas Medicinais/metabolismo , Transcriptoma
9.
BMC Genomics ; 22(1): 806, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749655

RESUMO

BACKGROUND: Paphiopedilum, commonly known as slipper orchid, is an important genus of orchid family with prominent horticultural value. Compared with conventional methods such as tillers and in vitro shoots multiplication, induction and regeneration of protocorm-like bodies (PLBs) is an effective micropropagation method in Paphiopedilum. The PLB initiation efficiency varies among species, hybrids and varieties, which leads to only a few Paphiopedilum species can be large-scale propagated through PLBs. So far, little is known about the mechanisms behind the initiation and maintenance of PLB in Paphiopedilum. RESULTS: A protocol to induce PLB development from seed-derived protocorms of Paphiopedilum SCBG Huihuang90 (P. SCBG Prince × P. SCBG Miracle) was established. The morphological characterization of four key PLB developmental stages showed that significant polarity and cell size gradients were observed within each PLB. The endogenous hormone level was evaluated. The increase in the levels of indoleacetic acid (IAA) and jasmonic acid (JA) accompanying the PLBs differentiation, suggesting auxin and JA levels were correlated with PLB development. Gibberellic acid (GA) decreased to a very low level, indicated that GA inactivation may be necessary for shoot apical meristem (SAM) development. Comparative transcriptomic profiles of four different developmental stages of P. SCBG Huihuang90 PLBs explore key genes involved in PLB development. The numbers of differentially expressed genes (DEGs) in three pairwise comparisons (A vs B, B vs C, C vs D) were 1455, 349, and 3529, respectively. KEGG enrichment analysis revealed that DEGs were implicated in secondary metabolite metabolism and photosynthesis. DEGs related to hormone metabolism and signaling, somatic embryogenesis, shoot development and photosynthesis were discussed in detail. CONCLUSION: This study is the first report on PLB development in Paphiopedilum using transcriptome sequencing, which provides useful information to understand the mechanisms of PLB development.


Assuntos
Orchidaceae , Transcriptoma , Orchidaceae/genética , Reguladores de Crescimento de Plantas , Sementes
10.
Zootaxa ; 5039(2): 291-298, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34811081

RESUMO

The article deals with the data about new find of the rare suctorian species Acineta euchaetae Sewell, 1951 on calanoid copepod host Euchaeta marina (Prestandrea, 1833) from the Arabian Sea. Seven young (sub-adult) individuals of the ciliate were observed on rear part of cephalothorax and on abdomen of adult male of copepod. The data about all known finds of A. euchaetae are discussed as well as the information on different developmental stages of the ciliate species. It is suggested that A. euchaetae is euryhaline species distributed in Eurasian coastal and inland waters and have preference for calanoid copepod hosts, but do not show specificity to any calanoid genus or species. The summarized diagnosis and refined systematic position of A. euchaetae are also provided.


Assuntos
Cilióforos , Copépodes , Cinetofragminóforos , Orchidaceae , Animais
11.
Zootaxa ; 5061(2): 361-368, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34810622

RESUMO

We describe the new species Entypus renata, sp. nov., from the Brazilian Atlantic Forest and report on its host. We also provide the first host records for Ageniella (Priophanes) erythroptera (Banks), Entypus bituberculatus (Gurin-Meville) and an undetermined species of Poecilopompilus Ashmead. In addition, we report behavioral aspects for these species, including a new ethological sequence for Poecilopompilus.


Assuntos
Himenópteros , Orchidaceae , Vespas , Animais , Florestas
12.
Biosensors (Basel) ; 11(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34677319

RESUMO

Infections of orchids by the Odontoglossum ringspot virus or Cymbidium mosaic virus cause orchid disfiguration and are a substantial source of economic loss for orchid farms. Although immunoassays can identify these infections, immunoassays are expensive, time consuming, and labor consuming and limited to sampling-based testing methods. This study proposes a noncontact inspection platform that uses a spectrometer and Android smartphone. When orchid leaves are illuminated with a handheld optical probe, the Android app based on the Internet of Things and artificial intelligence can display the measured florescence spectrum and determine the infection status within 3 s by using an algorithm hosted on a remote server. The algorithm was trained on optical data and the results of polymerase chain reaction assays. The testing accuracy of the algorithm was 89%. The area under the receiver operating characteristic curve was 91%; thus, the platform with the algorithm was accurate and convenient for infection screening in orchids.


Assuntos
Orchidaceae , Smartphone , Inteligência Artificial , Doenças das Plantas/virologia , Reação em Cadeia da Polimerase , Potexvirus , Tobamovirus
13.
Plant Physiol Biochem ; 167: 1024-1034, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34598022

RESUMO

Paphiopedilum spicerianum (P. spicerianum) is a rare orchid species with high ornamental value. Asymbiotic germination is the most efficient propagation method for conservation and commercial purposes because clonal propagation is very difficult and the separation of native species of Paphiopedilum through aseptic seeding is uncommon owing to their conservatism. However, a high protocorm developmental arresting rate during the asymbiotic germination is the major obstacle for seedling establishment. The fundamental understanding of embryo and protocorm developmental mechanisms will guide the development of an effective propagation method. The morphological and physiological characterization of the key developmental process of embryos and protocorms shows that the mature seeds of P. spicerianum consist of a spherical embryo without an endosperm. Seed coats become heavily lignified once the embryo is mature. Embryo cell size is relatively uniform, and significant structure polarity and cell size gradients occur at the early protocorm stage. The high level of auxin and cytokinin accumulation at the early stage of embryo development and protocorm stage may help to facilitate cell division. The transcriptome profiles of protocorms at three different developmental stages were compared to explore the regulatory mechanism of protocorm development. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that differentially expressed genes were implicated in secondary metabolite metabolism, plant hormone signal transduction and photosynthesis. The temporal expression patterns of candidate genes related to embryo and shoot development were analyzed to reveal their roles in protocorm development: in the early stage of protocorm development, embryonic development related genes such as SERKs and BBM1 were active, while in the late stage of protocorm, shoot apical meristem related genes such as WOX8, CLAVATA2, CUC2, and SCR were active.


Assuntos
Orchidaceae , Germinação , Orchidaceae/genética , Plântula , Sementes , Transcriptoma
14.
Plant Sci ; 312: 111053, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620448

RESUMO

Photosystem I (PSI) is the primary target of photoinhibition under fluctuating light (FL). In angiosperms, cyclic electron flow (CEF) around PSI is thought to be the main player protecting PSI under FL. The activation of CEF is linked to the thylakoid stacking, which is in turn affected by light intensity. However, it is unknown how pre-illumination affects the CEF activation and PSI redox state under FL. To address this question, we conducted a spectroscopic analysis under FL in Bletilla striata and Morus alba after pre-illumination at moderate light (ML, 611 µmol photons m-2 s-1) or high light (HL, 1455 µmol photons m-2 s-1). Our results indicated that both species displayed a transient over-reduction of PSI after a transition from low to high light, but the extent of PSI over-reduction under FL was largely alleviated by pre-illumination at HL when compared with pre-illumination under ML. Furthermore, pre-illumination at HL accelerated the activation rate of CEF but did not affect the activation of non-photochemical quenching and linear electron flow from photosystem II under FL. Therefore, such increased CEF activity by pre-illumination under HL alleviated PSI over-reduction under FL by facilitating the electron sink downstream of PSI. Taking together, pre-illumination at HL protects PSI under FL through acceptor-side regulation.


Assuntos
Adaptação Ocular/fisiologia , Morus/metabolismo , Orchidaceae/metabolismo , Oxirredução , Complexo de Proteína do Fotossistema I/metabolismo , Folhas de Planta/metabolismo
17.
Naturwissenschaften ; 108(5): 39, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477965

RESUMO

Florivores and rainfall generally have negative impacts on plant fecundity. However, in some cases, they can mediate fruit set. Some plants face severe pollen-limited fecundity and any additional fruit set, even if from self-pollination, can be advantageous. This is the case in some tropical deceptive orchids, such as the threatened Cyrtopodium hatschbachii. Here we test the hypothesis that florivory of the anther cap would facilitate rain-assisted autogamy in this species. In the field, we followed flowers in which the anther cap was removed by the orthopteran Stenopola sp. and found cases where pollinia self-deposited after rainfall and in one case this resulted in swelling of the column typical of fruit development. This event comprised 33% of all fruit set in the population in 2019. We then experimentally varied anther cap removal and rainfall in a factorial design and found increased fruit set in the group with cap removal (simulated florivory) followed by rain. The water absorption by pollinia makes them heavier, causing the stipe to bend. The droplet of water on the stigma then shrinks and pulls the pollinia back onto the stigma, causing self-pollination. Seeds from self-pollination have considerable viability and may allow population persistence, given that bee-mediated cross-pollination is uncertain and even absent in some years. Our study provides a unique example of how two unrelated factors (i.e., florivory and rain) that are detrimental alone may together promote fruit set.


Assuntos
Orchidaceae , Polinização , Animais , Abelhas , Flores , Pólen , Chuva
18.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4666-4673, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34581074

RESUMO

As the main active ingredient of the orchidaceous herb Bletilla striata, B. striata polysaccharide(BSP) has pharmacological activities such as promoting coagulation, anti-inflammation, anti-oxidation, promoting wound healing, anti-tumor, and immunomodulation, and is biodegradable and non-toxic. Additionally, it has the material properties of suspension thickening, film-forming adhesion, coating and solubilizing, targeting and slow releasing, effect-enhancing and toxicity-reducing, etc., playing the role of unification of medicines and excipients. Therefore, BSP has a wide application prospect in the fields of drug delivery system and trauma repair. This paper reviews the research progress of BSP application in new drug delivery systems and biomaterials based on the related li-terature in recent years, with the aim of providing reference for the further research and application of BSP.


Assuntos
Materiais Biocompatíveis , Orchidaceae , Sistemas de Liberação de Medicamentos , Polissacarídeos , Cicatrização
19.
Acta amaz ; 51(3): 214-223, set 2021.
Artigo em Inglês | LILACS | ID: biblio-1353497

RESUMO

As florestas ripárias no Brasil são importantes ecossistemas que sustentam uma enorme biodiversidade. Apesar de protegidas pela legislação brasileira, elas têm sofrido grandes impactos decorrentes da fragmentação florestal. As abelhas das orquídeas constituem um grupo chave de polinizadores na região Neotropical, porém, pouco se sabe sobre suas assembleias em florestas ripárias. Nós avaliamos o papel de fragmentos de floresta ripária e de terra-firme na conservação e manutenção da fauna de abelhas das orquídeas em uma paisagem urbana no sudoeste da Amazônia. Especificamente, avaliamos se assembleias de abelhas de fragmentos ripários e de terra-firme diferem significativamente em abundância, riqueza e composição de espécies. Também avaliamos se a abundância e a riqueza de espécies variam em função do tamanho do fragmento. Machos de abelhas foram atraídos por iscas odoríferas e coletados com redes entomológicas em 10 fragmentos florestais. Não houve diferença significativa entre fragmentos ripários e de terra-firme quanto à abundância, riqueza e composição de espécies, mas houve uma correlação positiva entre o tamanho do fragmento e a riqueza e abundância de espécies. Nossos resultados sugerem que, em uma paisagem urbana, os fragmentos de floresta ripária e de terra firme ainda podem manter 62,7% do número de espécies de abelhas das orquídeas conhecido para a região, reforçando o valor da conservação desses remanescentes florestais. Nossos dados indicam que esses fragmentos fornecem um habitat potencialmente importante para a manutenção das populações locais de abelhas na paisagem. (AU)


Assuntos
Abelhas , Florestas , Orchidaceae , Polinização
20.
J Toxicol Environ Health A ; 84(24): 987-1003, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34384338

RESUMO

Anoectochilus roxburghii Lind. (A. roxburghii) has promising anti-oxidant, hyperglycemic, hepatoprotective, and immunomodulatory activities as well as anti-tumor effects. However, the pharmacological actions of in vitro cultured plants remain to be determined. Therefore, the objective of the study was to assess in vitro cytotoxicity and in vivo potential toxicity of an extract derived from in vitro cultivated A. roxburghii, termed as iARE. The total flavonoid content and predominant flavonoid compounds of extract were identified and quantitatively analyzed. The in vitro cytotoxicity of iARE was examined using several cancer and normal cell lines. The apoptotic activity and expression of apoptosis-associated genes were also examined in MCF7 cells to determine the underlying mechanisms related to anti-proliferative effects. In vivo potential toxicity of iARE was assessed following acute and subchronic oral administration in Sprague Dawley rats. Quercetin, kaempferol, and isorhamnetin were three flavonoid components identified in iARE. The extract exerted cytotoxic effects on various cancer cells but not normal fibroblasts. Apoptosis in MCF7 cells was induced by iARE in a concentration-dependent manner associated with increased Bax/Bcl-2 ratio and reduced mitochondrial membrane potential ΔΨm, leading to release of cytochrome c, activation of caspase-3/7 and caspase-9, and cleavage of PARP. In the acute oral toxicity study, no mortality or toxicological signs were observed in rats at 1000 or 5000 mg/kg. In a subchronic oral toxicity study, iARE at a dosage of up to 1000 mg/kg produced no mortality or treatment-related adverse effects on general behavior, food intake, body weight, relative organ weights. No apparent marked changes in the histopathology of the liver and kidney were detected. Data demonstrated that iARE induced in vitro cytotoxic effects in cancer cells are associated with lackof invivo toxicity. Thus, iARE was suggested to be considered as apotential therapeutic candidate for cancer treatment.


Assuntos
Orchidaceae/química , Extratos Vegetais/toxicidade , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/análise , Flavonoides/toxicidade , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Orchidaceae/crescimento & desenvolvimento , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Testes de Toxicidade , Proteína X Associada a bcl-2/metabolismo
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