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1.
Phytother Res ; 34(10): 2518-2533, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32307775

RESUMO

Fruits of Terminalia chebula Retz. (Combretaceae) are widely used as crude drugs in various traditional medicine systems. The aim of this article is to review the available scientific information regarding the traditional uses, bioactive chemical constituents and the pharmacological activities of T. chebula. Numerous researches conducted on T. chebula have confirmed the presence of wide range of the phytochemicals such as flavonoids, tannins, phenolic acids and other bioactive compounds. T. chebula is also widely studied regarding its pharmacological activities such as antioxidant, hepatoprotective, neuroprotective, cytotoxic, antidiabetic, anti-inflammatory activities among others. However, more in vivo and clinical studies for mechanism-based pharmacological evaluation should be conducted in future to provide stronger scientific evidences for their traditional uses.


Assuntos
Frutas/fisiologia , Medicina Tradicional/métodos , Compostos Fitoquímicos , Terminalia/fisiologia , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/uso terapêutico , Flavonoides/isolamento & purificação , Flavonoides/uso terapêutico , Frutas/química , Humanos , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/uso terapêutico , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Taninos/isolamento & purificação , Taninos/uso terapêutico , Terminalia/química
2.
PLoS One ; 10(3): e0119634, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25781482

RESUMO

The harvest of non-timber forest products (NTFPs), together with other sources of anthropogenic disturbance, impact plant populations greatly. Despite this, conservation research on NTFPs typically focuses on harvest alone, ignoring possible confounding effects of other anthropogenic and ecological factors. Disentangling anthropogenic disturbances is critical in regions such as India's Western Ghats, a biodiversity hotspot with high human density. Identifying strategies that permit both use and conservation of resources is essential to preserving biodiversity while meeting local needs. We assessed the effects of NTFP harvesting (fruit harvest from canopy and lopping of branches for fruit) in combination with other common anthropogenic disturbances (cattle grazing, fire frequency and distance from village), in order to identify which stressors have greater effects on recruitment of three tropical dry forest fruit tree species. Specifically, we assessed the structure of 54 populations of Phyllanthus emblica, P. indofischeri and Terminalia chebula spread across the Nilgiri Biosphere Reserve, Western Ghats to ask: (1) How are populations recruiting? and (2) What anthropogenic disturbance and environmental factors, specifically forest type and elevation, are the most important predictors of recruitment status? We combined participatory research with an information-theoretic model-averaging approach to determine which factors most affect population structure and recruitment status. Our models illustrate that for T. chebula, high fire frequency and high fruit harvest intensity decreased the proportion of saplings, while lopping branches or stems to obtain fruit increased it. For Phyllanthus spp, recruitment was significantly lower in plots with more frequent fire. Indices of recruitment of both species were significantly higher for plots in more open-canopy environments of savanna woodlands than in dry forests. Our research illustrates an approach for identifying which factors are most important in limiting recruitment of NTFP populations and other plant species that may be in decline, in order to design effective management strategies.


Assuntos
Biodiversidade , Frutas/crescimento & desenvolvimento , Modelos Biológicos , Terminalia/fisiologia , Árvores/fisiologia , Humanos , Índia
3.
Appl Biochem Biotechnol ; 173(6): 1481-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24817511

RESUMO

The present study described an improved and reproducible in vitro regeneration system for Terminalia arjuna using nodal segment explants obtained from a mature plant. Shoot tips excised from in vitro proliferated shoots were encapsulated in 3 % sodium alginate and 100 mM CaCl2[Symbol: see text]2H2O for the development of synthetic seeds which may be applicable in short-term storage and germplasm exchange of elite genotype. Shoot multiplication was significantly influenced by a number of factors, namely types and concentrations of plant growth regulators, medium composition, repeated transfer of mother explants, subculturing of in vitro regenerated shoot clumps, agar concentrations, and temperature. Maximum numbers of shoots (16.50 ± 3.67) were observed on modified Murashige and Skoog (MMS) medium containing 0.5 mg l(-1) of benzylaminopurine (BAP) and 0.1 mg l(-1) of naphthalene acetic acid (NAA). To shortening the regeneration pathway, rooting of micropropagated shoots under in vitro condition was excluded and an experiment on ex vitro rooting was conducted and it was observed that the highest percentage of shoots rooted ex vitro when treated with indole-3-butyric acid (IBA, 250 mg l(-1)) + 2-naphthoxy acetic acid (NOA, 250 mg l(-1)) for 5 min. The well-developed ex vitro rooted shoots were acclimatized successfully in soilrite under greenhouse conditions with 80 % survival of plants. Randomly amplified polymorphic DNA (RAPD) analysis confirmed that all the regenerated plants were genetically identical to the mother plant, suggesting the absence of detectable genetic variation in the regenerated plantlets. To the best of our knowledge, this is the first report on synthetic seed production as well as ex vitro rooting and genetic fidelity assessment of micropropagated shoots of T. arjuna.


Assuntos
Terminalia/crescimento & desenvolvimento , Terminalia/genética , Cardiotônicos/isolamento & purificação , Impressões Digitais de DNA , DNA de Plantas/genética , Técnicas In Vitro , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Plantas Medicinais/genética , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/fisiologia , Regeneração , Terminalia/fisiologia
4.
PLoS One ; 8(1): e53441, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23320085

RESUMO

BACKGROUND: Burgeoning antibiotic resistance in Pseudomonas aeruginosa has necessitated the development of anti pathogenic agents that can quench acylhomoserine lactone (AHL) mediated QS with least risk of resistance. This study explores the anti quorum sensing potential of T. chebula Retz. and identification of probable compounds(s) showing anti QS activity and the mechanism of attenuation of P. aeruginosa PAO1 virulence factors. METHODS AND RESULTS: Methanol extract of T. chebula Retz. fruit showed anti QS activity using Agrobacterium tumefaciens A136. Bioactive fraction (F7), obtained by fractionation of methanol extract using Sephadex LH20, showed significant reduction (p<0.001) in QS regulated production of extracellular virulence factors in P. aeruginosa PAO1. Biofilm formation and alginate were significantly (p<0.05) reduced with enhanced (20%) susceptibility to tobramycin. Real Time PCR of F7 treated P. aeruginosa showed down regulation of autoinducer synthase (lasI and rhlI) and their cognate receptor (lasR and rhlR) genes by 89, 90, 90 and 93%, respectively. Electrospray Ionization Mass Spectrometry also showed 90 and 64% reduction in the production of 3-oxo-C(12)HSL and C(4)HSL after treatment. Decrease in AHLs as one of the mechanisms of quorum quenching by F7 was supported by the reversal of inhibited swarming motility in F7-treated P. aeruginosa PAO1 on addition of C(4)HSL. F7 also showed antagonistic activity against 3-oxo-C(12)HSL-dependent QS in E. coli bioreporter. C. elegans fed on F7-treated P. aeruginosa showed enhanced survival with LT50 increasing from 24 to 72 h. LC-ESI-MS of F7 revealed the presence of ellagic acid derivatives responsible for anti QS activity in T. chebula extract. CONCLUSIONS: This is the first report on anti QS activity of T. chebula fruit linked to EADs which down regulate the expression of lasIR and rhlIR genes with concomitant decrease in AHLs in P. aeruginosa PAO1 causing attenuation of its virulence factors and enhanced sensitivity of its biofilm towards tobramycin.


Assuntos
Regulação para Baixo/fisiologia , Ácido Elágico/análogos & derivados , Genes Bacterianos/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/genética , Terminalia/fisiologia , Virulência/genética , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Caenorhabditis elegans/microbiologia , Regulação para Baixo/efeitos dos fármacos , Ácido Elágico/isolamento & purificação , Ácido Elágico/farmacologia , Ligases/genética , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Percepção de Quorum/efeitos dos fármacos , Terminalia/química , Fatores de Transcrição/genética , Virulência/efeitos dos fármacos
5.
J Chem Ecol ; 32(7): 1431-43, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16724271

RESUMO

Resource availability, degree of herbivore damage, genetic variability, and their interactions influence the allocation of investment by plants to resistance and tolerance traits. We evaluated the independent and interactive effects of soil nutrients and moisture, and simulated the effects of herbivore damage on condensed tannins (resistance) and growth/regrowth (tolerance) traits of Terminalia sericea, a deciduous tree in the Kalahari desert that constitutes a major component of livestock diet. We used a completely crossed randomized-block design experiment to examine the effects of nutrients, water availability, and herbivore damage on regrowth and resistance traits of T. sericea seedlings. Plant height, number of branches, internode length, leaf area, leaf mass for each seedling, combined weight of stems and twigs, and root mass were recorded. Condensed tannin concentrations were 22.5 and 21.5% higher under low nutrients and low soil moisture than under high nutrient and high water treatment levels. Tannin concentrations did not differ significantly between control and experimental seedlings 2 mo after simulated herbivore damage. Tannin concentrations correlated more strongly with growth traits under low- than under high-nutrient conditions. No trade-offs were detected among individual growth traits, nor between growth traits and condensed tannins. T. sericea appeared to invest more in both resistance and regrowth traits when grown under low-nutrient conditions. Investment in the resistance trait (condensed tannin) under high-nutrient conditions was minimal and, to a lesser degree, correlated with plant growth. These results suggest that T. sericea displays both resistance and tolerance strategies, and that the degree to which each is expressed is resource-dependent.


Assuntos
Mamíferos/fisiologia , Solo , Terminalia/fisiologia , Adaptação Biológica , Animais , Ecossistema , Comportamento Alimentar , Namíbia , Proantocianidinas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Terminalia/crescimento & desenvolvimento
6.
Mol Cell Biochem ; 281(1-2): 87-93, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16328960

RESUMO

The present investigation was carried out to evaluate the antioxidant nature of ethanolic extract of Terminalia arjuna bark (EETA) on N-nitrosodiethylamine (DEN) induced liver cancer in male Wistar albino rats. Liver cancer was induced by single intraperitonial injection of DEN (200 mg/kg). After 2 weeks of DEN administration, Phenobarbital (PB) was given to promote the cancer for up to 14 successive weeks. EETA extract (400 mg/kg) was given post-orally for 28 days to hepatocellular carcinoma-bearing rats. After the experimental period, all the animals were sacrificed and serum, liver and kidney samples were collected for further biochemical analysis. The levels of lipid peroxides (LPO) under basal and also in the presence of inducers (H(2)O(2), ascorbate and FeSO(4)) were estimated in serum, liver and kidney of control and experimental animals. Enzymic antioxidants, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and non-enzymic antioxidants like Vitamin C (Vit-C) and Vitamin E (Vit-E) levels were determined in all the groups of animals. A significant increase in LPO levels were observed while the levels of enzymic and non-enzymic antioxidants were decreased, when subjected to DEN induction. These altered enzyme levels were ameliorated significantly by administration of EETA at the concentration of 400 mg/kg in drug-treated animals. This protective effect of EETA was associated with inhibition of LPO induced by DEN and to maintain the antioxidant enzyme levels. Our results show an antioxidant activity of T. arjuna bark against DEN-induced liver cancer.


Assuntos
Antioxidantes/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Plantas Medicinais/fisiologia , Terminalia/fisiologia , Alquilantes/toxicidade , Animais , Carcinoma Hepatocelular/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar
7.
Biomedica ; 22(4): 524-8, 2002 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-12596450

RESUMO

In 1997, our laboratory reported for the first time the isolation of Cryptococcus neoformans var. gattii serotype C associated with almond tree (Terminalia catappa) detritus. This finding led to a more detailed follow up of the association between the plant and the yeast. Preliminary data have shown that survival of the yeast in almond trees seedlings goes beyond 100 days. The aim of the present study was to establish if under the conditions previously studied, C. neoformans var. gattii would remain viable for longer periods. A total of 83 almond tree seedings, 20-40 cm high, were inoculated with C. neoformans var. gattii serotype C (INS-755). Assays were carried out inoculating the stem or the soil where the seedlings were planted. Observations were undertaken for a period of up to 12 months. As processing techniques we employed the endophytic fungi procedure (stems), maceration (roots, leaves) and standard suspension method (soils). Additionally, microscopic visualization of the yeast in plant tissues was done with trypan blue plus lactophenol. C. neoformans var. gattii was recovered from the inoculated plants for a period of up to 12 months post-inoculation; additionally, the fungus had the capacity to migrate from the stem to the soil and viceversa, without causing macroscopic or microscopic alterations in the plant tissues. This finding suggests that there appears to be an association between the host plant and C. neoformans var. gattii in the environment.


Assuntos
Cryptococcus neoformans/fisiologia , Terminalia/microbiologia , Corantes , Cryptococcus neoformans/isolamento & purificação , Ecossistema , Fungos , Interações Hospedeiro-Parasita/fisiologia , Folhas de Planta/microbiologia , Folhas de Planta/fisiologia , Terminalia/fisiologia , Azul Tripano
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