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1.
Metab Brain Dis ; 38(3): 1025-1034, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36522491

RESUMEN

Oxidative stress (OS) is well established as a major event in Alzheimer's disease (AD) pathology. One of the mostly-researched classes of antioxidants to manage with overwhelming OS include flavonoids. This study was aimed to investigate the protective effect of A. congolensis extract (HEEAC) on AlCl3-mediated AD-like OS and assess the contribution of its antioxidant flavonoid contents. Female Wistar (250-300 g) rats received orally 50 mg/Kg bw of AlCl3, followed one hour later by doses (150 or 300 mg/kg) of HEEAC or vitamin E at 100 mg/kg daily for eight consecutive weeks. OS related biomarkers were evaluated at the end of treatment. To assess the contribution of flavonoid contents to its activity, HEEAC was fractioned using solvent of varying polarities. Flavonoid-rich extracts obtained were tested for their antioxidant capacity. AlCl3 administration significantly lowered antioxidant enzymes (catalase, glutathione peroxidase) and aconitase levels, reduced total thiol and thiol protein levels and increased lipid peroxidation and protein oxidation levels in brain. When co-administrated with HEEAC at 150 mg/kg, all of these OS related biomarkers were significantly moderated. The efficacity of the extract was significantly higher than vitamin E. Flavonoid-rich fractions extracted mainly n-butanol fraction show strong antioxidant activity, which can be considered as the major antioxidant fraction of this plant. HEEAC protect brain cells against oxidative damage induced by AlCl3, specifically through the strong antioxidant property of its n-butanol flavonoid-rich fraction, which may be a promising agent for preventing oxidative damage in AD.


Asunto(s)
Enfermedad de Alzheimer , Sapotaceae , Ratas , Animales , Antioxidantes/uso terapéutico , Cloruro de Aluminio , Flavonoides/farmacología , Flavonoides/uso terapéutico , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/prevención & control , Sapotaceae/metabolismo , 1-Butanol/farmacología , Ratas Wistar , Estrés Oxidativo , Vitamina E/farmacología , Peroxidación de Lípido , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico
2.
Braz J Med Biol Res ; 55: e12381, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36350974

RESUMEN

Glial cells have been implicated in temporal lobe epilepsy in humans and in its models. Astrocytes are lost in several brain regions after acute seizures induced by pilocarpine and may suffer hyperplasia at subsequent time points. This study investigated the effect of N-methyl-(2S,4R)-trans-4-hydroxy-L-proline (NMP) on astrocytes exposed to cytotoxic concentrations of pilocarpine. Astrocytes were incubated with pilocarpine (half maximal inhibitory concentration (IC50)=31.86 mM) for 24 h. Afterwards, they were treated with NMP at concentrations ranging from 3.12 to 100 µg/mL for 24 h. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cytoplasmic reactive oxygen species (ROS) and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry using 2',7'-dichlorofluorescein diacetate (DCFH-DA) and rhodamine-123 (Rho123), respectively. Expression of glial fibrillary acidic protein (GFAP) and voltage-dependent anion channel-1 (VDAC-1) were measured by western blot. Pilocarpine significantly decreased cell viability and mitochondrial potential and increased ROS concentration significantly by 6.7 times compared to the control. NMP concentrations ≥25 µg/mL protected astrocytes against pilocarpine-induced injury in a concentration-dependent manner. Concomitantly, NMP reduced cytoplasmic ROS accumulation to 27.3, 24.8, and 12.3% in the groups treated with 25, 50, and 100 µg/mL NMP, respectively. NMP also protected mitochondria from pilocarpine-induced depolarization. These effects were associated with improvement of pilocarpine-induced GFAP and VDAC-1 overexpression, which are important biomarkers of astrocyte dysfunction. In conclusion, the improvement of ROS accumulation, VDAC-1 overexpression, and mitochondrial depolarization are possible mechanisms of the NMP protective action on reactive astrocytes.


Asunto(s)
Pilocarpina , Sapotaceae , Humanos , Pilocarpina/farmacología , Astrocitos , Especies Reactivas de Oxígeno/metabolismo , Sapotaceae/metabolismo
3.
Molecules ; 27(19)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36235295

RESUMEN

Plant saponins are abundant and diverse natural products with a great potential for use in drug-discovery research. Here, we evaluated extracts of saponins-rich fractions of argan leaves and argan oil extraction byproducts (shell, pulp, press cake) for their effect on melanogenesis. Results show that from among the samples tested, only the saponins-rich fraction from leaves (ALS) inhibited melanin production in B16 murine melanoma (B16) cells. The mechanism of the melanogenesis inhibition was elucidated by determining the protein and mRNA expression of melanogenesis-associated enzymes tyrosinase (TYR), tyrosinase-related protein 1 (TRP1), and dopachrome tautomerase (DCT), and microphthalmia-associated transcription factor (MITF), and performing DNA microarray analysis. Results showed that 10 µg/mL ALS significantly inhibited melanogenesis in B16 cells and human epidermal melanocytes by 59% and 48%, respectively, without cytotoxicity. The effect of ALS on melanogenesis can be attributed to the decrease in TYR, TRP1, and MITF expression at the protein and mRNA levels. MITF inhibition naturally led to the downregulation of the expression of Tyr and Trp1 genes. Results of the DNA microarray analysis revealed the effect on melanogenesis-associated cAMP and Wnt signaling pathways' genes. The results of this study suggest that ALS may be used in cosmeceuticals preparations for hyperpigmentation treatment.


Asunto(s)
Esclerosis Amiotrófica Lateral , Cosmecéuticos , Melanoma Experimental , Saponinas , Sapotaceae , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Cosmecéuticos/farmacología , ADN/metabolismo , Humanos , Melaninas , Melanocitos/metabolismo , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Ratones , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Monofenol Monooxigenasa/metabolismo , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Hojas de la Planta/metabolismo , ARN Mensajero/metabolismo , Saponinas/metabolismo , Saponinas/farmacología , Sapotaceae/metabolismo
4.
Metab Brain Dis ; 37(7): 2467-2481, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35867181

RESUMEN

Development of neuropsychiatric disorder is associated with stress-related increase in pro-inflammatory cytokines. Chrysophyllum albidum fruit is an edible tropical fruit containing vitamins and phenolic compounds, well known for their anti-inflammatory and antioxidant activities. This study was designed to investigate the neuroprotective effect of C. albidum fruit extract (CAFE) on stress and lipopolysaccharide (LPS)-induced behavioral and neurochemical impairments in mice. Male Swiss mice were divided into 6 groups (n = 6). Groups 1-3 were orally treated daily for 14 days with normal saline (0.1 mL/10 g), CAFE (100 mg/kg) and Ferulic acid (FA, 10 mg/kg), and left in home cage as controls. Groups 4-6 were treated similarly but subjected to repeated social defeat (RSD) stress using the resident-intruder model from days 1-14. The RSD-animals were injected with LPS (125 µg/kg, i.p) 60 min after each RSD session from days 8-14. Neurobehavioral functions: locomotor, cognitive and anxiety-like behaviors were assessed 24 h after the last treatment. Pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α), dopamine, acetylcholinesterase, glutamic acid decarboxylase (GAD), malondialdehyde, nitrites, and reduced glutathione (GSH) were determined in brain tissue. CAFE significantly attenuated RSD and LPS-induced hypolocomotion, cognitive impairment and anxiety-like behavior when compared to the control. Treatment with CAFE also significantly reversed the negative effects of RSD and LPS on pro-inflammatory cytokines, dopamine, acetylcholinesterase, GAD, and oxidative-nitrosative stress levels. The findings clearly indicated that Chrysophyllum albidum fruit demonstrated neuroprotective effects and can play a key role in mitigating against chronic stress and inflammation linked to neuropsychiatric disorders.


Asunto(s)
Fármacos Neuroprotectores , Sapotaceae , Animales , Ratones , Masculino , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Lipopolisacáridos/farmacología , Acetilcolinesterasa , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Derrota Social , Frutas/química , Frutas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6 , Nitritos/análisis , Nitritos/farmacología , Dopamina , Glutamato Descarboxilasa/análisis , Glutamato Descarboxilasa/farmacología , Solución Salina/farmacología , Sapotaceae/química , Sapotaceae/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Glutatión/farmacología , Citocinas , Malondialdehído/farmacología , Vitaminas , Estrés Oxidativo
5.
Carbohydr Polym ; 274: 118632, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34702455

RESUMEN

Nanotechnology is a route of choice that improves administration and efficacy of bioactive compounds. In this study, nanoemulgels were prepared using microfibrillated cellulose from Argania spinosa shell (AS-MFC) and Argan shell (ASE) or Argan press cake extracts (APC) as natural emulsifiers. Oil-in-water (O/W) nanoemulsions were prepared using different natural emulsifiers or synthetic emulsifiers and presented a nano size (d3,2 < 140 nm). Following that, the nanoemulsions were incorporated within AS-MFC matrix and rheological properties confirmed a shear thinning behavior. Confocal micrographs of nanoemulgels confirmed the dispersion of nanoemulsions in the AS-MFC network without affecting the nanoemulsions stability. Finally, in vitro bioassay on B16F10 using ASE or APC nanoemulsions was conducted. This study confirmed cell permeation in B16F10 cells of formulated nanoemulsions and the upregulation of melanin content up to 30% more that the untreated cells. This study designed novel MFC nanoemulgel with high potential application in healthcare and cosmetic field.


Asunto(s)
Celulosa/química , Emulsionantes/química , Extractos Vegetales/química , Sapotaceae/metabolismo , Tamaño de la Partícula
6.
Plant J ; 107(4): 1040-1055, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34053139

RESUMEN

The hyperaccumulator Pycnandra acuminata is a New Caledonian rainforest tree known to have the highest concentration of nickel in any living organism, with 25 wt% nickel in its latex. All trees (with a diameter of >10 cm) and soil profiles in a 0.25-hectare permanent plot were sampled to assess the biogeochemical compartmentalisation of nickel in a dense stand of P. acuminata trees. Nickel stable isotope analysis permitted insights into the cycling of nickel in this ecosystem. The total tree biomass of the plot was calculated to be 281 tonnes ha-1 , which contained 0.44 kg of cobalt, 49.1 kg of manganese, 257 kg of nickel and 6.76 kg of zinc. Nickel stable isotope analysis identified the biotic origin of the nickel in the soil upper layers, with P. acuminata shoots enriched in lighter nickel isotopes. The δ60 Ni latex signature suggests that long-distance transport, radial xylem and phloem loading are at play in P. acuminata.


Asunto(s)
Bosques , Níquel/análisis , Níquel/farmacocinética , Sapotaceae/metabolismo , Suelo/química , Biomasa , Isótopos/análisis , Látex/química , Metales Pesados/análisis , Nueva Caledonia , Hojas de la Planta/química , Sapotaceae/efectos de los fármacos , Oligoelementos/análisis , Oligoelementos/farmacocinética , Árboles , Clima Tropical , Xilema/química
7.
Curr Protein Pept Sci ; 22(1): 60-73, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33143624

RESUMEN

Salt stress is one of the major abiotic stresses that negatively affect crops worldwide. Plants have evolved a series of mechanisms to cope with the limitations imposed by salinity. Molecular mechanisms, including the upregulation of cation transporters such as the Na+/H+ antiporters, are one of the processes adopted by plants to survive in saline environments. NHX antiporters are involved in salt tolerance, development, cell expansion, growth performance and disease resistance of plants. They are integral membrane proteins belonging to the widely distributed CPA1 sub-group of monovalent cation/H+ antiporters and provide an important strategy for ionic homeostasis in plants under saline conditions. These antiporters are known to regulate the exchange of sodium and hydrogen ions across the membrane and are ubiquitous to all eukaryotic organisms. With the genomic approach, previous studies reported that a large number of proteins encoding Na+/H+ antiporter genes have been identified in many plant species and successfully introduced into desired species to create transgenic crops with enhanced tolerance to multiple stresses. In this review, we focus on plant antiporters and all the aspects from their structure, classification, function to their in silico analysis. On the other hand, we performed a genome-wide search to identify the predicted NHX genes in Argania spinosa L. We highlighted for the first time the presence of four putative NHX (AsNHX1-4) from the Argan tree genome, whose phylogenetic analysis revealed their classification in one distinct vacuolar cluster. The essential information of the four putative NHXs, such as gene structure, subcellular localization and transmembrane domains was analyzed.


Asunto(s)
Genoma de Planta , Proteínas de Plantas/genética , Tolerancia a la Sal/genética , Sapotaceae/genética , Intercambiadores de Sodio-Hidrógeno/genética , Estrés Fisiológico/genética , Secuencia de Aminoácidos , Arabidopsis/clasificación , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Homeostasis/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Dominios Proteicos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Salinidad , Sapotaceae/clasificación , Sapotaceae/metabolismo , Homología de Secuencia de Aminoácido , Intercambiadores de Sodio-Hidrógeno/química , Intercambiadores de Sodio-Hidrógeno/metabolismo
8.
Molecules ; 25(24)2020 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-33352625

RESUMEN

Chrysophyllum albidum Linn (African star apple) is a fruit with extensive nutritional and medicinal benefits. The fruit and kernel in the seed are both edible. Strains of lactic acid bacteria (LAB) were isolated from fermented seeds and assessed for probiotic characteristics. The extracts in both the unfermented and the fermented aqueous extracts from the kernels obtained from the seeds of C. albidum were subjected to analysis using the gas chromatography/mass spectrometry (GC-MS) method. This analysis identified the bioactive compounds present as possible substrate(s) for the associated organisms inducing the fermentation and the resultant biotransformed products formed. Three potential probiotic LAB strains identified as Lactococcus raffinolactis (ProbtA1), Lactococcus lactis (ProbtA2a), and Pediococcus pentosaceus (ProbtA2b) were isolated from the fermented C. albidum seeds. All strains were non hemolytic, which indicated their safety, Probt (A1, A2a, and A2b) grew in an acidic environment (pH 3.5) during the 48-h incubation time, and all three strains grew in 1% bile, and exhibited good hydrophobicity and auto-aggregation properties. Mucin binding proteins was not detected in any strain, and bile salt hydrolase was detected in all the strains. l-lactic acid (28.57%), norharman (5.07%), formyl 7E-hexadecenoate (1.73%), and indole (1.51%) were the four major constituents of the fermented kernel of the C. albidum, while 2,5-dimethylpyrazine (C1, 1.27%), 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one (C2, 2.90%), indole (C3, 1.31%), norharman (C4, 3.01%), and methyl petroselinate (C5, 4.33%) were the five major constituents of the unfermented kernels. The isolated LAB are safe for consumption. The fermenting process metabolized C1, C2, and C5, which are possible starter cultures for the growth of probiotics. Fermentation is an essential tool for bioengineering molecules in foods into safe and health beneficial products.


Asunto(s)
Biotransformación/fisiología , Fermentación/fisiología , Frutas/metabolismo , Frutas/microbiología , Sapotaceae/metabolismo , Sapotaceae/microbiología , Microbiología de Alimentos/métodos , Lactococcus/aislamiento & purificación , Lactococcus lactis/aislamiento & purificación , Pediococcus pentosaceus/aislamiento & purificación , Probióticos , Semillas/metabolismo , Semillas/microbiología
9.
Food Chem ; 297: 124749, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31253289

RESUMEN

Argan oil is precious oil with food and cosmetic uses. In recent years, this oil has been subject to an increasing national and international demand. The present work aims at studying the effect of clones and age, year of harvest and geographical origin on Argan oil quality and chemical composition. The results indicate that age does not affect Argan oil quality and fatty acids content. However, clones had a significant effect on fatty acids and tocopherol levels. Saturated and unsaturated fatty acids were highly influenced by the year of harvest and geographical origin, presumably due to climatic conditions. Unsaturated fatty acids varied from 78.28% to 81.77%. Depending on clones, total tocopherols varied from 687.40 mg/kg to 1068 mg/kg. This study is useful for the choice of clones with the aim of developing Argan trees orchards destined to oil production.


Asunto(s)
Aceites de Plantas/química , Sapotaceae/química , Cromatografía de Gases , Clima , Ácidos Grasos Insaturados/análisis , Frutas/química , Frutas/metabolismo , Aceites de Plantas/análisis , Análisis de Componente Principal , Sapotaceae/metabolismo , Factores de Tiempo , Tocoferoles/análisis
10.
Appl Microbiol Biotechnol ; 103(9): 3727-3736, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30915502

RESUMEN

Shea tree (Vitellaria paradoxa) is one economically important plant species that mainly distributes in West Africa. Shea butter extracted from shea fruit kernels can be used as valuable products in the food and cosmetic industries. The most valuable composition in shea butter was one kind of triacylglycerol (TAG), 1,3-distearoyl-2-oleoyl-glycerol (SOS, C18:0-C18:1-C18:0). However, shea butter production is limited and little is known about the genetic information of shea tree. In this study, we tried to reveal genetic information of shea tree and identified shea TAG biosynthetic genes for future shea butter production in yeast cell factories. First, we measured lipid content, lipid composition, and TAG composition of seven shea fruits at different ripe stages. Then, we performed transcriptome analysis on two shea fruits containing obviously different levels of SOS and revealed a list of TAG biosynthetic genes potentially involved in TAG biosynthesis. In total, 4 glycerol-3-phosphate acyltransferase (GPAT) genes, 8 lysophospholipid acyltransferase (LPAT) genes, and 11 diacylglycerol acyltransferase (DGAT) genes in TAG biosynthetic pathway were predicted from the assembled transcriptome and 14 of them were cloned from shea fruit cDNA. Furthermore, the heterologous expression of these 14 potential GPAT, LPAT, and DGAT genes in Saccharomyces cerevisiae changed yeast fatty acid and lipid profiles, suggesting that they functioned in S. cerevisiae. Moreover, two shea DGAT genes, VpDGAT1 and VpDGAT7, were identified as functional DGATs in shea tree, showing they might be useful for shea butter (SOS) production in yeast cell factories.


Asunto(s)
Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sapotaceae/genética , Triglicéridos/biosíntesis , Levaduras/genética , Levaduras/metabolismo , Vías Biosintéticas , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Frutas/genética , Frutas/metabolismo , Ingeniería Metabólica , Sapotaceae/enzimología , Sapotaceae/metabolismo , Transcriptoma
11.
Int J Mol Sci ; 18(11)2017 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-29084170

RESUMEN

This review summarizes available data on argan fruit botany, geographical distribution, traditional uses, environmental interest, socioeconomic role, phytochemistry, as well as health beneficial effects and examination of future prospects. In particular, ethnomedical uses of argan fruits are carried out throughout Morocco where it has been used against various diseases. Different classes of bioactive compounds have been characterized including essential oils, fatty acids, triacylglycerols, flavonoids and their newly reported acylglycosyl derivatives, monophenols, phenolic acids, cinnamic acids, saponins, triterpenes, phytosterols, ubiquinone, melatonin, new aminophenols along with vitamin E among other secondary metabolites. The latter have already shown a wide spectrum of in vitro, and ex vivo biologicalactivities including antioxidant, anti-inflammatory, anti-diabetic, antihypertensive, anti-hypercholesterolemia, analgesic, antimicrobial, molluscicidal anti-nociceptive and anticancer potential. Argan flesh (pulp) contains a broad spectrum of polyphenolic compounds which may have utility for incorporation into nutraceuticals and cosmeceuticals relevant to the food, cosmetic and health industries. Further research is recommended, especially on the health beneficial effects of the aminophenols.


Asunto(s)
Frutas/química , Fitoquímicos/química , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sapotaceae/química , Frutas/metabolismo , Humanos , Metaboloma , Metabolómica/métodos , Marruecos , Fenoles/química , Aceites de Plantas/química , Sapotaceae/metabolismo
12.
Acta Pol Pharm ; 73(5): 1249-1257, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29638065

RESUMEN

The indigenous medicinal plant species, Bfidelia micrantha and Sideyoxylon ineime (both known as 'uMhlalamagwababa' in isiZulu), are used interchangeably by traditional healers in KwaZulu-Natal, South Africa, to treat a variety of ailments due to morphological similarities. In this study, a phytochemical investigation was done on B. inicrantha and S. inenne to determine if they have a chemotaxonomic link. Three penta- cyclic triterpenes, one carotenoid and one megastigmane were isolated from S. inerme. Two flavonoids and two triterpenes were isolated from B. micrantha. These compounds were not previously isolated from these plant species. The antioxidant capacity of the isolated flavonoids was comparable to that of the known antioxidant - ascorbic acid. Profiling of the fruit extracts from both plant species by gas chromatography-mass spectrometry showed different classes of compounds in the extracts. This study corroborates the use of S. inerme and B. mici-ntha by traditional healers but does not support their use interchangeably.


Asunto(s)
Antioxidantes/farmacología , Euphorbiaceae/metabolismo , Extractos Vegetales/farmacología , Sapotaceae/metabolismo , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Cromatografía de Gases y Espectrometría de Masas , Extractos Vegetales/análisis , Triterpenos/aislamiento & purificación , Triterpenos/farmacología
13.
Nat Prod Commun ; 8(1): 21-3, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23472451

RESUMEN

The transfer of heavy metals and trace elements from argan forest soil into the wood, leaves, almonds, and argan oil was studied. Analyzed metals were: chromium, cadmium, copper, zinc, lead, calcium, phosphorus, potassium, and magnesium. Correlations linking different behaviors of the studied heavy metals and trace elements observed by multidimensional analysis were attributed to partial-spatial variations. Whereas the RV-coefficient of wood, leaf, almond and oil groups was high, the soil group correlated poorly with the other groups.


Asunto(s)
Metales Pesados/metabolismo , Sapotaceae/metabolismo , Oligoelementos/metabolismo , Metales Pesados/análisis , Modelos Biológicos , Marruecos , Análisis de Componente Principal , Suelo/análisis , Oligoelementos/análisis , Árboles/metabolismo
14.
Colloids Surf B Biointerfaces ; 68(2): 184-92, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19022632

RESUMEN

A new biosorbent has been prepared by coating Chrysophyllum albidum (Sapotaceae) seed shells with chitosan and/or oxidizing agents such as sulfuric acid. This study investigated the technical feasibility of activated and modified activated C. albidum seed shells carbons for the adsorption of chromium(VI) from aqueous solution. The sorption process with respect to its equilibria and kinetics as well as the effects of pH, contact time, adsorbent mass, adsorbate concentration and particle size on adsorption was also studied. The most effective pH range was found to be between 4.5 and 5 for the sorption of the metal ion. The pseudo-first-order rate equation by Lagergren and pseudo-second-order rate equation were tested on the kinetic data, the adsorption process followed pseudo-second-order rate kinetics, also, isotherm data was analyzed for possible agreement with the Langmuir and Freundlich adsorption isotherms, the Freundlich and Langmuir models for dynamics of metal ion uptake proposed in this work fitted the experimental data reasonably well. However, equilibrium sorption data were better represented by Langmuir model than Freundlich. The adsorption capacity calculated from Langmuir isotherm was 84.31, 76.23 and 59.63mgCr(VI)/g at initial pH of 3.0 at 30 degrees C for the particle size of 1.00-1.25mm with the use of 12.5, 16.5 and 2.1g/L of CACASC, CCASC and ACASC adsorbent mass, respectively. This readily available adsorbent is efficient in the uptake of Cr(VI) ion in aqueous solution, thus, it could be an excellent alternative for the removal of heavy metals and organic matter from water and wastewater.


Asunto(s)
Cromo/aislamiento & purificación , Residuos Industriales , Sapotaceae/metabolismo , Semillas/metabolismo , Eliminación de Residuos Líquidos , Acetilación , Adsorción , Biodegradación Ambiental , Quitina/metabolismo , Quitosano/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Factores de Tiempo
15.
Phytochemistry ; 69(1): 240-51, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17765935

RESUMEN

Targeted liquid chromatography-mass spectrometry (LC-MS) technology using size exclusion chromatography and metabolite profiling based on gas chromatography-mass spectrometry (GC-MS) were used to study the nickel-rich latex of the hyperaccumulating tree Sebertia acuminata. More than 120 compounds were detected, 57 of these were subsequently identified. A methylated aldaric acid (2,4,5-trihydroxy-3-methoxy-1,6-hexan-dioic acid) was identified for the first time in biological extracts and its structure was confirmed by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. After citric acid, it appears to be one of the most abundant small organic molecules present in the latex studied. Nickel(II) complexes of stoichiometry NiII:acid=1:2 were detected for these two acids as well as for malic, itaconic, erythronic, galacturonic, tartaric, aconitic and saccharic acids. These results provide further evidence that organic acids may play an important role in the transport and possibly in the storage of metal ions in hyperaccumulating plants.


Asunto(s)
Adipatos/química , Látex/química , Níquel/química , Níquel/metabolismo , Sapotaceae/química , Adipatos/metabolismo , Cromatografía Líquida de Alta Presión , Análisis de Fourier , Cromatografía de Gases y Espectrometría de Masas , Látex/metabolismo , Ligandos , Espectroscopía de Resonancia Magnética , Metilación , Modelos Moleculares , Conformación Molecular , Níquel/análisis , Sapotaceae/metabolismo , Suelo/análisis
16.
Plant Cell Environ ; 30(11): 1411-21, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17897411

RESUMEN

Although deep roots can contribute substantially to whole-tree water use, little is known about deep root functioning because of limited access for in situ measurements. We used a cave system on the Edwards Plateau of central Texas to investigate the physiology of water transport in roots at 18-20 m depth for two common tree species, Quercus fusiformis and Bumelia lanuginosa. Using sap flow and water potential measurements on deep roots, we found that calculated root hydraulic conductivity (RHC) fluctuated diurnally for both species and decreased under shading for B. lanuginosa. To assess whether these dynamic changes in RHC were regulated during initial water absorption by fine roots, we used an ultra-low flowmeter and hydroxyl radical inhibition to measure in situ fine root hydraulic conductivity (FRHC) and aquaporin contribution to FRHC (AQPC), respectively. During the summer, FRHC and AQPC were found to cycle diurnally in both species, with peaks corresponding to the period of highest transpirational demand at midday. During whole-tree shade treatments, B. lanuginosa FRHC ceased diurnal cycling and decreased by 75 and 35% at midday and midnight, respectively, while AQPC decreased by 41 and 30% during both time periods. A controlled growth-chamber study using hydroponically grown saplings confirmed daily cycling and shade-induced reductions in FRHC and AQPC. Winter measurements showed that the evergreen Q. fusiformis maintained high FRHC and AQPC throughout the year, while the deciduous B. lanuginosa ceased diurnal cycling and exhibited its lowest annual values for both parameters in winter. Adjustments in FRHC and AQPC to changing canopy water demands may help the trees maintain the use of reliable water resources from depth and contribute to the success of these species in this semi-arid environment.


Asunto(s)
Acuaporinas/metabolismo , Raíces de Plantas/metabolismo , Árboles/metabolismo , Agua/metabolismo , Ecosistema , Fenómenos Geológicos , Geología , Quercus/metabolismo , Sapotaceae/metabolismo
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