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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469269

RESUMO

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.

2.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350312

RESUMO

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Assuntos
Solo , Banco de Sementes , Paquistão , Plantas , Sementes , Ecossistema , Poaceae
3.
Braz J Biol ; 84: e262479, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700584

RESUMO

The methanolic, chloroformic and aqueous extract of Achillea millefolium and Chaerophyllum villosum were investigated for cytotoxicity, phytotoxic and insecticidal activities. Cytotoxicity was investigated by brine shrimp lethality assay indicating that the crude methanolic extract of A.millefolium and chloroformic extract of C.villosum revealed highest mortality of brine shrimps with (LD50 of 52.60 µg/ml) and (14.81 µg/ml). Phytotoxicity was evaluated using the Lemna minor bioassay which revealed that the crude methanolic extract of A.millefolium and C.villosum extract has maximum inhibition of Lemna minor with (Fl50 6.60 µg/ml) and (0.67 µg/ml).The insecticidal activity showed that among all the insects studied it was observed that methanolic extract of A. millefoliumand C. villosum was highly toxic to Sphenoptera dadkhani with (LD50=4.17 µg/ml) and (0.34 µg/ml). From the present study it can be concluded that different extracts from A. millefolium and C. villosum showed good cytotoxic, phytotoxic and insecticidal activity in a dose dependent manner.


Assuntos
Achillea , Antineoplásicos , Inseticidas , Extratos Vegetais/toxicidade , Inseticidas/toxicidade
4.
Braz J Biol ; 84: e260566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35613215

RESUMO

Chrozophora tinctoria (L.) A.Juss. is herbaceous, monecious annual plant used traditionally to cure gastrointestinal disorders. The present study was carried out to find the bioactive compounds by Gas Chromatography-Mass Spectrometry, the acetylcholinesterase inhibitory potential acute toxicity, and emetic activity present in the ethyl acetate fraction of Chrozophora tinctoria (EAFCT) and dichloromethane fraction of Chrozophora tinctoria (DCMFCT). The compounds detected in both fractions were mostly fatty acids, with about seven compounds in EAFCT and 10 in DCMFCT. These included pharmacologically active compounds such as imipramine, used to treat depression, or hexadecanoic acid methyl ester, an antioxidant, nematicide, pesticide, hypocholesterolemic, 9,12,15-Octadecatrienoic acid, ethyl ester, (Z,Z,Z)- is used as a cancer preventive, antiarthritic, antihistaminic, hepatoprotective, insectifuge, nematicide, Pentadecanoic acid, 14-methyl-, methyl ester have antifungal, antimicrobial and antioxidant activities, 10-Octadecanoic acid, methyl ester have the property to decrease blood cholesterol, Antioxidant and antimicrobial, 1-Eicosanol is used as an antibacterial, 1-Hexadecene has antibacterial, antioxidant, and antifungal activities. Both DCMFCT and EAFCT fractions inhibited acetylcholinesterase (AChE) activity with IC50 values of 10 µg and 130 µg, respectively. Both the fractions were found to be toxic in a dose-dependent manner, inducing emesis at 0.5g onward and lethargy and mortality from 3-5 g upwards. Both the fractions combined with distilled water showed highly emetic activity. The significant increase in the number of vomits was shown by EAFCT plus distilled water which are 7.50±1.29, 7.25±3.10, and 11.75±2.22 number of vomits at 1g, 2g, and 3g/kg concentration respectively, while DCMFCT plus distilled water showed 5.25±2.22, 7.50±2.52 and 10.25±2.22 number of vomits at 1g, 2, and 3g/kg correspondingly. The antiemetic standard drug metoclopramide has a higher impact against the emesis induced by both the fractions than dimenhydrinate. Metoclopramide decreases the number of vomits caused by EAFCT to 1.00±0.00, 2.00±0.00, 4.00±1.00 at 1g, 2, and 3g/kg sequentially, while dimenhydrinate decreases the number of vomits to 1.33±0.58, 2.33±1.15, 4.33±0.58 at 1g, 2, and 3g respectively. In the same way, Metochloprimide decreases the number of emesis caused by DcmCt from 5.25±2.22, 7.50±2.52, 10.25±2.22 to 1.33±0.58, 2.33±1.1, 4.33±0.58 at 1g, 2, and 3g/kg concentrations. The present study is the first documented report that scientifically validates the folkloric use of Chrozophora tinctoria as an emetic agent.


Assuntos
Dimenidrinato , Euphorbiaceae , Acetilcolinesterase , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Dimenidrinato/análise , Eméticos/análise , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Metoclopramida/análise , Modelos Animais , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Vômito , Água
5.
Braz J Biol ; 84: e255485, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34878007

RESUMO

The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Assuntos
Banco de Sementes , Solo , Ecossistema , Paquistão , Plantas , Poaceae , Sementes
6.
Oecologia ; 196(4): 1139-1152, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34331568

RESUMO

Invasive species are a major cause of biodiversity loss worldwide, but their impact on communities and the mechanisms driving those impacts are varied and not well understood. This study employs functional diversity metrics and guilds-suites of species with similar traits-to assess the influence of an invasive tree (Tamarix spp.) on riparian plant communities in the southwestern United States. We asked: (1) What traits define riparian plant guilds in this system? (2) How do the abundances of guilds vary along gradients of Tamarix cover and abiotic conditions? (3) How does the functional diversity of the plant community respond to the gradients of Tamarix cover and abiotic conditions? We found nine distinct guilds primarily defined by reproductive strategy, as well as growth form, height, seed weight, specific leaf area, drought and anaerobic tolerance. Guild abundance varied along a covarying gradient of local and regional environmental factors and Tamarix cover. Guilds relying on sexual reproduction, in particular, those producing many light seeds over a long period of time were more strongly associated with drier sites and higher Tamarix cover. Tamarix itself appeared to facilitate more shade-tolerant species with higher specific leaf areas than would be expected in resource-poor environments. Additionally, we found a high degree of specialization (low functional diversity) in the wettest, most flood-prone, lowest Tamarix cover sites as well as in the driest, most stable, highest Tamarix cover sites. These guilds can be used to anticipate plant community response to restoration efforts and in selecting appropriate species for revegetation.


Assuntos
Rios , Árvores , Biodiversidade , Espécies Introduzidas , Plantas
7.
Antibiot Khimioter ; 39(9-10): 3-5, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7695446

RESUMO

Interactions in the bio-inorganic systems of the copper ions and azalide (azithromycin) were analyzed by spectroscopic methods (atom-absorption spectroscopy, IR and UV spectrometry in the visible spectrum) and electrochemical methods (potentiometry). The system samples within molar ratios of the metal ion and ligand of 10:1 to 1:10 and wide pH ranges were tested. Formation of a compound consisting of the metal ion and ligand at a ratio of 1:1 was detected. The experimental data showed that the product of the compound solubility equaled 9.8.10(-14) (pH 7.0, 0.1 KNO3).


Assuntos
Azitromicina/química , Cobre/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Potenciometria , Solubilidade , Espectrofotometria
8.
Antibiot Khimioter ; 34(3): 186-9, 1989 Mar.
Artigo em Russo | MEDLINE | ID: mdl-2751372

RESUMO

The dynamics of changes in the microelemental composition during cultivation of the nystatin-producing organisms and synthesis of the antibiotic was studied. The microelemental composition of the raw materials and media used for the cultivation was also studied. Interrelation between the dynamics of the changes in the microelemental composition and the main parameters of the process of the antibiotic production were analyzed. It was revealed that during the first stage of the culture development characterized by the maximum rate of the biomass accumulation the ions of ferrum, cuprum and arsenic were consumed along with consumption of the main nutrients (carbohydrates, nitrogen and phosphorus). During the second stage of the culture development i.e. after 36 hours the ferrum ions were liberated into the fermentation broth while the content of cuprum and arsenic continued to decrease though at a lower rate. Marked shifts in the specific rates of the changes in the contents of ferrum and cuprum ions in the fermentation broth were also observed at the beginning of the second phase of the culture development. It was shown possible to control the process of nystatin biosynthesis by the microelemental composition of the media for cultivation of the antibiotic-producing organism.


Assuntos
Arsênio/metabolismo , Cobre/metabolismo , Ferro/metabolismo , Nistatina/biossíntese , Streptomyces/metabolismo , Meios de Cultura , Técnicas In Vitro , Streptomyces/crescimento & desenvolvimento , Fatores de Tempo
9.
Antibiot Khimioter ; 33(9): 643-6, 1988 Sep.
Artigo em Russo | MEDLINE | ID: mdl-3218986

RESUMO

The contents of microelements such as Fe, Cu, Zn and As in samples of raw materials including food grade ones used in preparation of nutrient media for cultivation of antibiotic-producing organism and water were determined spectrophotometrically with using complex forming organic reagents. An original procedure for the sample combustion in the assay was developed. The natural background levels of the microelements in the nutrient media used in manufacture of some antibiotics were estimated.


Assuntos
Bactérias/crescimento & desenvolvimento , Meios de Cultura/análise , Oligoelementos/análise
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