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1.
Chem Biodivers ; 20(11): e202301010, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37814192

RESUMEN

The objective of this study was to study the diversity of endophytic fungi isolated from Ceiba pentandra and to isolate their bioactive chemical compounds. The methodology used during this study consisted in isolating endophytic fungi from the bark of C. pentandra on Potato Agar. The isolates obtained were identified on the basis of the ITS regions of their ribosomal DNA. Antibacterial screening of the mycelium of endophytic fungi isolated was evaluated against multidrug-resistant E. coli and S. aureus strains. This screening led to the selection of isolates EC 321 and EC 28 for their ability to effectively inhibit the growth of the bacterial strains tested. EC 321 was grown and fermented on rice medium. Secondary metabolites were extracted with ethyl acetate. From the crude extract, secalonic acid A was isolated and identified by chromatographic and NMR. The in vitro activity of secalonic acid A against the growth of multiresistant bacterial strains was evaluated. Secalonic acid A was active against all multidrug-resistant bacterial strains E. coli 942, E. coli 4814, S. aureus 931, S. aureus 934, S. aureus MRSA 1872 and K. pneumonia 815 with respective MICs of 18.75; 18.75; 18.75; 4.7; 37.5 and 37.5 µg/mL.


Asunto(s)
Bombacaceae , Ceiba , Staphylococcus aureus , Corteza de la Planta , Escherichia coli , Hongos , Antibacterianos/química , Bacterias , Endófitos/química
2.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36555275

RESUMEN

Gastrointestinal diseases, such as peptic ulcers, are caused by a damage in the gastric mucosa provoked by several factors. This stomach injury is regulated by many inflammatory mediators and is commonly treated with proton-pump inhibitors, histamine H2 receptor blockers and antacids. However, various medicinal plants have demonstrated positive effects on gastric ulcer treatment, including plants of the Ceiba genus. The aim of this study was to evaluate the antiulcer and anti-inflammatory activities of the stem bark ethanolic extract of Ceiba speciosa (A. St.-Hil.) Ravenna. We performed a preliminary quantification of phenolic compounds by high-performance liquid chromatography-diode array detection (HPLC-DAD), followed by the prospection of other chemical groups through nuclear magnetic resonance (NMR) spectroscopy. A set of in vitro assays was used to evaluate the extract potential regarding its antioxidant activity (DPPH: 19.83 ± 0.34 µg/mL; TPC: 307.20 ± 6.20 mg GAE/g of extract), effects on cell viability and on the release of TNF-α in whole human blood. Additionally, in vivo assays were performed to evaluate the leukocyte accumulation and total protein quantification in carrageenan-induced air pouch, as well as the antiulcerogenic effect of the extract on an ethanol-induced ulcer in rats. The extract contains flavonoids and phenolic compounds, as well as sugars and quinic acid derivatives exhibiting potent antioxidant activity and low toxicity. The extract reduced the release of TNF-α in human blood and inhibited the activity of p38α (1.66 µg/mL), JAK3 (5.25 µg/mL), and JNK3 (8.34 µg/mL). Moreover, it reduced the leukocyte recruitment on the pouch exudate and the formation of edema, reverting the effects caused by carrageenan. The extract presented a significant prevention of ulcer formation and a higher reduction than the reference drug, Omeprazole. Therefore, C. speciosa extract has demonstrated relevant therapeutic potential for the treatment of gastric diseases, deserving the continuation of further studies to unveil the mechanisms of action of plant bioactive ingredients.


Asunto(s)
Antiulcerosos , Ceiba , Extractos Vegetales , Úlcera Gástrica , Animales , Humanos , Ratas , Antiulcerosos/farmacología , Antioxidantes/farmacología , Carragenina/efectos adversos , Ceiba/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/metabolismo , Úlcera
3.
Molecules ; 27(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36432208

RESUMEN

The increasing degradation of fossil fuels has motivated the globe to turn to green energy solutions such as biofuel in order to minimize the entire reliance on fossil fuels. Green renewable resources have grown in popularity in recent years as a result of the advancement of environmental technology solutions. Kapok fiber is a sort of cellulosic fiber derived from kapok tree seeds (Ceiba pentandra). Kapok Fiber, as a bio-template, offers the best alternatives to provide clean and renewable energy sources. The unique structure, good conductivity, and excellent physical properties exhibited by kapok fiber nominate it as a highly favored cocatalyst for deriving solar energy processes. This review will explore the role and recent developments of KF in energy production, including hydrogen and CO2 reduction. Moreover, this work summarized the potential of kapok fiber in environmental applications, including adsorption and degradation. The future contribution and concerns are highlighted in order to provide perspective on the future advancement of kapok fiber.


Asunto(s)
Ceiba , Ceiba/química , Biocombustibles , Adsorción , Carbohidratos , Combustibles Fósiles
4.
Molecules ; 27(11)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35684492

RESUMEN

In this work, the extraction procedure of a natural pigment from the flower of Ceiba speciosa (A. St.-Hil.) was optimized by response surface methodology. It is the first time that the extraction of the flower pigment of C. speciosa (FPCS) has been reported, along with an evaluation of its stability and biological activity under various conditions, and an exploration of its potential use as a food additive and in medicine. Specifically, the effects of ethanol concentration, solid-liquid ratio, temperature and time on the extraction rate of FPCS were determined using a Box-Behnken design. The optimum extraction conditions for FPCS were 75% ethanol with a solid-liquid ratio of 1:75 mg/mL) at 66 °C for 39 min. The purification of FPCS using different macroporous resins showed that D101 performed best when the initial mass concentration of the injection solution was 1.50 mg/mL, resulting in a three-fold increase in color value. The yield of dry flowers was 9.75% of fresh petals and the FPCS extraction efficiency was 43.2%. The effects of light, solubility, pH, temperature, sweeteners, edible acids, redox agents, preservatives and metal ions on FPCS were also investigated. Furthermore, the characteristics of FPCS were determined by spectrophotometry at a specific wavelength using the Lambert-Beer law to correlate the mass of FPCS with its absorbance value. An acute toxicological test performed according to Horne's method showed that FPCS is a non-toxic extract and thus may be used as a food additive or in other ingestible forms. Finally, western blotting showed that FPCS prevents lipopolysaccharide-induced hippocampal oxidative stress in mice. The study suggests that FPCS may function as an antioxidant with applications in the food, cosmetics and polymer industries.


Asunto(s)
Ceiba , Animales , Antioxidantes/farmacología , Etanol , Flores , Aditivos Alimentarios , Ratones , Extractos Vegetales/farmacología
5.
Molecules ; 26(7)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33917541

RESUMEN

This work aimed to evaluate the physical, chemical and antioxidant properties of Ceiba aesculifolia subsp. parvifolia (CAP) tuber and determinate rheological, thermal, physicochemical and morphological properties of the starch extracted. The CAP tuber weight was 3.66 kg; the edible yield was 82.20%. The tuber presented a high hardness value (249 N). The content of carbohydrates (68.27%), crude fiber (15.61%) and ash (9.27%) from the isolated starch, reported in dry weight, were high. Phenolic compounds and flavonoid content of CAP tuber peel were almost 3-fold higher concerning the pulp. CAP tuber starch exhibited a pseudoplastic behavior and low viscosity at concentrations of 5-15%. Purity percentage and color parameters describe the isolated starch as high purity. Thermal characteristics indicated a higher degree of intermolecular association within the granule. Pasting properties describes starch with greater resistance to heat and shear. CAP tuber starch has X-ray diffraction patterns type A. The starch granules were observed as oval and diameters ranging from 5 to 30 µm. CAP tuber could be a good source of fiber and minerals, while its peel could be used for extracting bioactive compounds. Additionally, the starch separated from this tuber could be employed as a thickening agent in food systems requiring a low viscosity and subjected to high temperatures.


Asunto(s)
Ceiba/química , Tubérculos de la Planta/química , Reología , Almidón/química , Antioxidantes/análisis , Rastreo Diferencial de Calorimetría , Color , Elasticidad , Flavonoides/análisis , Polifenoles/análisis , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/ultraestructura , Temperatura , Viscosidad , Difracción de Rayos X
6.
New Phytol ; 225(2): 727-739, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31469437

RESUMEN

Carbon (C) dynamics in canopy and roots influence whole-tree carbon fluxes, but little is known about canopy regulation of tree-root activity. Here, the patterns and dynamics of canopy-root C coupling are assessed in tropical trees. Large aeroponics facility was used to study the root systems of Ceiba pentandra and Khaya anthotheca saplings directly at different light intensities. In Ceiba, root respiration (Rr ) co-varied with photosynthesis (An ) in large saplings (3-to-7-m canopy-root axis) at high-light, but showed no consistent pattern at low-light. At medium-light and in small saplings (c. 1-m axis), Rr tended to decrease transiently towards midday. Proximal roots had higher Rr and nonstructural carbohydrate concentrations than distal roots, but canopy-root coupling was unaffected by root location. In medium-sized Khaya, no Rr pattern was observed, and in both species, Rr was unrelated to temperature. The early-afternoon increase in Rr suggests that canopy-root coupling is based on mass flow of newly fixed C in the phloem, whereas the early-morning rise in Rr with An indicates an additional coupling signal that travels faster than the phloem sap. In large saplings and potentially also in higher trees, light and possibly additional environmental factors control the diurnal patterns of canopy-root coupling, irrespective of root location.


Asunto(s)
Ceiba/fisiología , Luz , Meliaceae/fisiología , Hojas de la Planta/efectos de la radiación , Raíces de Plantas/efectos de la radiación , Árboles/efectos de la radiación , Clima Tropical , Dióxido de Carbono/metabolismo , Ceiba/efectos de la radiación , Meliaceae/efectos de la radiación , Floema/metabolismo , Floema/efectos de la radiación , Fotones , Fotosíntesis/efectos de la radiación , Corteza de la Planta/anatomía & histología , Hojas de la Planta/fisiología , Raíces de Plantas/fisiología , Transpiración de Plantas/efectos de la radiación , Reología , Solubilidad , Almidón/metabolismo , Azúcares/metabolismo , Temperatura , Árboles/fisiología , Xilema/anatomía & histología
7.
Molecules ; 25(5)2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-32106610

RESUMEN

This study aimed to evaluate the chemical composition by gas chromatography-mass spectrometry (GC-MS) and Nuclear Magnetic Resonance (NMR) analyses, the antioxidant activities evaluated by different in vitro assays namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), Ferric Reducing Ability Power (FRAP), and ß-carotene bleaching tests, and the inhibitory effects of enzymes linked to obesity (lipase, α-amylase, and α-glucosidase) of fixed seed oil of Ceiba speciosa (A. St.-Hil.). Fourteen compounds were identified. Linoleic acid (28.22%) was the most abundant followed by palmitic acid (19.56%). Malvalic acid (16.15%), sterculic acid (11.11%), and dihydrosterculic acid (2.74%) were also detected. C. speciosa fixed oil exerted a promising ABTS radicals scavenging activity with an IC50 value of 10.21 µg/mL, whereas an IC50 of 77.44 µg/mL against DPPH+ radicals was found. C. speciosa fixed oil inhibited lipase with an IC50 value of 127.57 µg/mL. The present investigation confirmed the functional properties of C. speciosa fixed oil, and proposes its use as valuable source of bioactive constituents.


Asunto(s)
Ceiba/química , Ácidos Grasos/química , Aceites de Plantas/química , Semillas/química , Antioxidantes/química , Ácidos Grasos/clasificación , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química
8.
J Environ Manage ; 219: 340-349, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29753978

RESUMEN

This work reports on a series of thermally-bonded, hybrid and oil-sorbent nonwovens developed from binary and tertiary mixing of cotton, kapok, and three varieties of milkweed fibers (Asclepias Syriaca, Calotropis Procera and Calotropis Gigantea) and polypropylene fibers. The physical and chemical properties of the fibers were investigated to examine their oleophilic character. It was observed that all the fiber surfaces were covered with natural wax. Further, kapok and milkweed fibers were found to have less cell wall thickness and high void ratio. Oil sorption and retention characteristics of these fibers were studied in loose fibrous form as well as in structured assembly form (thermally-bonded nonwovens) using high density oil and diesel oil. The effects of fiber diameter, fiber cross-sectional shape, fiber surface area and porosity on the oil sorption behavior were discussed. An excellent and a selective oil sorption behavior of milkweed fibers (Calotropis Procera and Calotropis Gigantea) blended with cotton and polypropylene fibers were observed. The maximum oil sorption capacity of the developed thermal bonded nonwoven was 40.16 g/g for high density (HD) oil and 23.00 g/g for diesel oil. Further, a high porosity combined with high surface area played a major role in deciding the oil sorption and retention characteristics.


Asunto(s)
Aceites , Plantas , Polipropilenos , Ceiba , Estudios Transversales , Textiles
9.
Water Sci Technol ; 78(5-6): 1137-1147, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30339538

RESUMEN

Hollow tubular structured kapok fibers (Ceiba pentandra) were coated with polyaniline (PANI) molecules using an in situ oxidative polymerization technique. The tubular morphology of the kapok fibers was retained after PANI coating. The Fourier transform infrared (FT-IR) spectrum of the PANI-coated kapok fibers illustrated the vibration modes associated with the presence of PANI molecules. The PANI-treated kapok fibers achieved complete wettability with water molecules (zero water contact angle) from initially being highly hydrophobic (contact angle = 120°). In the present work, the removal of contaminants such as methyl orange dye and Cu(II) from aqueous solution using polyaniline-coated kapok fibers was investigated. Isotherm studies show that the removal of methyl orange dye (R2 ≥ 0.959) and Cu(II) (R2 ≥ 0.972) using PANI-coated kapok fibers follow the Langmuir isotherm model with maximum sorption capacities determined to be 75.76 and 81.04 mg/g, respectively. Based from thermodynamic studies, the sorption of methyl orange dye and Cu(II) are endothermic, feasible and spontaneous. Furthermore, kinetic studies show that the both processes follow a pseudo-second-order model, implying that the rate-determining step is chemisorption.


Asunto(s)
Compuestos de Anilina/química , Compuestos Azo/química , Ceiba , Cobre/química , Purificación del Agua/métodos , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Iones , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua , Contaminantes Químicos del Agua/química
10.
Int J Syst Evol Microbiol ; 67(5): 1158-1162, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28073396

RESUMEN

Strain XMU 110T, isolated from the rhizosphere soil of a flowering tree, Ceiba speciosa, was characterized by polyphasic taxonomy. Phylogenetic analysis based on 16S rRNA gene comparisons revealed that strain XMU 110T showed the highest similarity of 97.9 % to Nonomuraea jabiensis DSM 45507T, and indicated the closest relatives were Nonomuraearoseoviolaceasubsp.roseoviolacea ATCC 27297T (97.8 % 16S rRNA gene sequence similarity) and Nonomuraea salmonea DSM 43678T (97.4 %) after a neighbour-joining analysis. The phenotypic characteristics, as well as the DNA-DNA relatedness values between strain XMU 110T and N. roseoviolaceasubsp. roseoviolacea ATCC 27297T (48.07±1.99 %) and N. salmonea DSM 43678T (40.55±8.30 %), distinguished the novel strain from its closest phylogenetic neighbours. The morphological, physiological and chemotaxonomic characteristics such as phospholipid type, diagnostic diamino acid of the peptidoglycan, whole-cell sugars, major menaquinones and major fatty acids further supported the assignment of strain XMU 110T to the genus Nonomuraea. The G+C content of the genomic DNA was 66.2 mol%. Based on the taxonomic data, strain XMU 110Trepresents a novel species of the genus Nonomuraea, for which the name Nonomuraea ceibae sp. nov. is proposed. The type strain is XMU 110T (=MCCC 1K03213T= KCTC 39826T).


Asunto(s)
Actinomycetales/clasificación , Ceiba/microbiología , Filogenia , Rizosfera , Microbiología del Suelo , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
11.
Water Environ Res ; 88(7): 611-6, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27329057

RESUMEN

The surface of a kapok fiber was coated with Dopamine (DOPA) through a three-dimensional (3-D) polymerization. Such surface-modified kapok fiber was useful in deactivating microbial activity of microorganisms such as bacteria. The morphology of the surface-modified kapok fiber was analyzed with a field emission scanning electron microscope (FE-SEM). After a silver coating process along with DOPA functionalization, a strong antibacterial property was observed against Escherichia coli (E. coli), using a direct contact method. Almost 100% of bacterial cells were deactivated in 4 h, also showing a complete hindrance to a bacterial growth for 48 h. With the help of the images of FE-SEM and its analysis, the mechanism of an antibacterial assay was enlightened and reasonably estimated that silver ions from the poly-DOPA-coated kapok fiber with silver (KF-DOPA/Ag) led to alterations of cell morphology. This 3-D composite successfully interacted in vitro with functional groups in terms of bacterial deactivation.


Asunto(s)
Antibacterianos/farmacología , Ceiba/química , Dopamina/química , Escherichia coli/efectos de los fármacos , Plata/química
12.
New Phytol ; 227(3): 680-682, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32602597

Asunto(s)
Ceiba , Árboles
13.
Am J Bot ; 102(6): 983-91, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26101422

RESUMEN

PREMISE OF THE STUDY: Selfing and mixed mating systems are prevalent in many flowering plants. Purging of genetic load can occur in these species, reducing negative effects of selfing. Long-term studies of the temporal and spatial variation of selfing rates and inbreeding depression at the individual level are necessary to understand the forces that maintain selfing as a mating strategy in these species. METHODOLOGY: We used microsatellites to estimate selfing rates in seeds and seedlings over 6 years in a population of Ceiba pentandra in southwestern Costa Rica. We studied the correlation of selfing with early seedling vigor variables to test for inbreeding depression. KEY RESULTS: Selfing rates varied widely among maternal trees. However, we found high consistency of selfing rates for individuals among years. Selfing rate did not influence early fitness traits, suggesting a lack of inbreeding depression at this stage. Maternal effects were a predominant source of variation for early vigor variables. CONCLUSIONS: Variability in selfing rates among trees may be partly explained by genetic variation in a late-acting self-incompatibility system or low, early-acting genetic load in some individuals. This population did not show evidence of early inbreeding depression in traits related to seed vigor probably from complete or partial purging as a result of repeated selfing of a fraction of the population or from strong maternal effects. Expression of genetic load at later developmental stages or in more stressful natural conditions may explain differences in inbreeding levels between seeds and adults.


Asunto(s)
Ceiba/fisiología , Autofecundación/fisiología , Árboles/fisiología , Clima Tropical , Ceiba/genética , Costa Rica , Frutas/crecimiento & desarrollo , Variación Genética , Carácter Cuantitativo Heredable , Reproducción , Tamaño de la Muestra , Semillas/crecimiento & desarrollo , Árboles/genética
14.
J Environ Sci (China) ; 27: 21-32, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25597659

RESUMEN

Kapok fiber corresponds to the seed hairs of the kapok tree (Ceiba pentandra), and is a typical cellulosic fiber with the features of thin cell wall, large lumen, low density and hydrophobic-oleophilic properties. As a type of renewable natural plant fiber, kapok fiber is abundant, biocompatible and biodegradable, and its full exploration and potential application have received increasing attention in both academic and industrial fields. Based on the structure and properties of kapok fiber, this review provides a summary of recent research on kapok fiber including chemical and physical treatments, kapok fiber-based composite materials, and the application of kapok fiber as an absorbent material for oils, metal ions, dyes, and sound, with special attention to its use as an oil-absorbing material, one predominant application of kapok fiber in the coming future.


Asunto(s)
Ceiba/química , Contaminantes Ambientales/química , Contaminación Ambiental/prevención & control , Adsorción , Colorantes/química , Metales/química , Ruido/prevención & control , Contaminación por Petróleo/prevención & control
15.
Water Environ Res ; 86(4): 360-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24851332

RESUMEN

In this paper, an oil sorbent based on superhydrophobic kapok fiber fabricated by the sol-gel method was used for the selective sorption of oil from the surface of artificial seawater. The effects of process parameters such as seawater pH, seawater temperature, and contact time on the extent of oil sorption were investigated. The as-prepared fiber showed higher oil sorption capacity than raw fiber in both the trenchant acid and alkaline seawater environment. Results of the kinetic studies show that the sorption process follows pseudo-second-order reaction kinetics. The thermodynamic investigations demonstrate that the sorption process is spontaneous and endothermic. In addition, the as-prepared fiber can float on the water surface after the sorption of oil, which facilitates the post-processing of oil-loaded fiber. The modified fiber might provide a simple method for the removal and collection of oil on the water surface.


Asunto(s)
Ceiba/química , Restauración y Remediación Ambiental/métodos , Agua de Mar/química , Contaminantes Químicos del Agua/química , Contaminación Química del Agua/prevención & control , Absorción , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Termodinámica
16.
PLoS One ; 19(4): e0299361, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557644

RESUMEN

Seasonally Dry Tropical Forests (SDTFs) located on limestone outcrops are vulnerable to degradation caused by timber logging and limestone extraction for cement production. Some of these forests represent the last remnants of native vegetation cover, functioning as isolated islands. Ceiba pubiflora (Malvaceae) is a tree frequently found on limestone outcrops in the central region of Brazil. This study aimed to evaluate the genetic diversity and identify suitable populations for the establishment of Management Units (MUs) for conservation. Inter-simple sequence repeat markers were employed to assess the genetic diversity in ten populations sampled from the Caatinga, Cerrado, and Atlantic Forest biomes. The species exhibited substantial genetic diversity (HT = 0.345; PLP = 97.89%). Populations SAH, JAN, and MON demonstrated elevated rates of polymorphic loci (> 84.2%) along with notable genetic diversity (He > 0.325). Additionally, these populations were the primary contributors to gene flow. The analysis of molecular variance (AMOVA) indicated that most genetic variation occurs within populations (91.5%) than between them. In the Bayesian analysis, the ten populations were clustered into five groups, revealing the presence of at least three barriers to gene flow in the landscape: 1) the Central Plateau or Paranã River valley; 2) near the Espinhaço mountains or the São Francisco River valley; and 3) around the Mantiqueira mountain range, Chapada dos Veadeiros plateau, and disturbed areas. A positive and statistically significant correlation was observed between genetic (θB) and geographic distances (r = 0.425, p = 0.008). Based on these findings, we propose the establishment of Management Units in Minas Gerais state, encompassing the (1) southern region (MIN population), (2) central region (SAH population), and (3) north region (MON population), as well as in Goiás state, covering the (4) Central Plateau region. These units can significantly contribute to preserving the genetic diversity of these trees and protecting their habitat against ongoing threats.


Asunto(s)
Ceiba , Malvaceae , Variación Genética , Teorema de Bayes , Ecosistema , Brasil
17.
Ann Bot ; 112(2): 291-6, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23250916

RESUMEN

BACKGROUND AND AIMS: This study is a first step in a multi-stage project aimed at determining allometric relationships among the tropical tree organs, and carbon fluxes between the various tree parts and their environment. Information on canopy-root interrelationships is needed to improve understanding of above- and below-ground processes and for modelling of the regional and global carbon cycle. Allometric relationships between the sizes of different plant parts will be determined. METHODS: Two tropical forest species were used in this study: Ceiba pentandra (kapok), a fast-growing tree native to South and Central America and to Western Africa, and Khaya anthotheca (African mahogany), a slower-growing tree native to Central and Eastern Africa. Growth and allometric parameters of 12-month-old saplings grown in a large-scale aeroponic system and in 50-L soil containers were compared. The main advantage of growing plants in aeroponics is that their root systems are fully accessible throughout the plant life, and can be fully recovered for harvesting. KEY RESULTS: The expected differences in shoot and root size between the fast-growing C. pentandra and the slower-growing K. anthotheca were evident in both growth systems. Roots were recovered from the aeroponically grown saplings only, and their distribution among various diameter classes followed the patterns expected from the literature. Stem, branch and leaf allometric parameters were similar for saplings of each species grown in the two systems. CONCLUSIONS: The aeroponic tree growth system can be utilized for determining the basic allometric relationships between root and shoot components of these trees, and hence can be used to study carbon allocation and fluxes of whole above- and below-ground tree parts.


Asunto(s)
Carbono/metabolismo , Ceiba/crecimiento & desarrollo , Meliaceae/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/crecimiento & desarrollo , África , Biomasa , Tallos de la Planta/crecimiento & desarrollo , Plantones/crecimiento & desarrollo , Especificidad de la Especie , Árboles , Clima Tropical , Madera
18.
J Anim Ecol ; 82(5): 1106-15, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23550633

RESUMEN

1. Chiropterophilic flowers secrete sugar nectar with low-Nitrogen (N hereafter) content and small amounts of amino acids, which may function to attract animals; nevertheless, the role that micronutrients have on the foraging decisions of Neotropical nectarivorous bats is unknown. 2. We offered the nectar specialist Leptonycteris yerbabueanae and the omnivore Glossophaga soricina pairs of experimental diets mimicking either the N content or the relative abundance of 17 amino acids found in the floral nectar from the main plant species visited by these bats in a tropical dry forest. We addressed the following research questions: (i) Do bats select N-containing or sugar-only nectar differently based on bats' N nutritional status? (ii) Does the presence of N in nectar affect the capacity of bats to discriminate and select other nectar traits such as sugar concentration? and (iii) Are bats able to distinguish among the flavours generated by the amino acid relative abundance present in the nectar from plants they typically encounter in nature? 3. Our results showed that: (i) bats did not consider nectar N content regardless of their N nutritional condition, (ii) the nectar specialist L. yerbabuenae showed a preference for the most concentrated sugar-only nectar but changed to be indifferent when nectar contained N, and (iii) L. yerbabuenae preferred diets without amino acids and preferred the taste of the amino acids present in the nectar of Pachycereus pecten (Cactaceae) over those present in the nectar of Ceiba aesculifolia (Bombacaceae). 4. Our results suggest that regardless of the low concentrations at which N and amino acids are present in floral nectar, their presence affects bats' food selection by interfering with the bats' ability to detect differences in sugar concentrations, and by offering particular flavours that can be perceived and selected by nectarivorous bats. We discuss the ecological implications of the presence of N and amino acids in nectar on bats' foraging decisions.


Asunto(s)
Aminoácidos/metabolismo , Quirópteros/fisiología , Preferencias Alimentarias/fisiología , Nitrógeno/metabolismo , Néctar de las Plantas/química , Aminoácidos/análisis , Animales , Cactaceae/química , Carbohidratos/análisis , Ceiba/química , Dieta , Masculino , Desnutrición , México , Nitrógeno/análisis
19.
Am J Bot ; 100(6): 1095-101, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23720432

RESUMEN

PREMISE OF THE STUDY: Tropical forest loss and fragmentation isolate and reduce the size of remnant populations with negative consequences for mating patterns and genetic structure of plant species. In a 4-yr study, we determined the effect of fragmentation on mating patterns and pollen pool genetic structure of the tropical tree Ceiba aesculifolia in two habitat conditions: isolated trees in disturbed areas (≤3 trees/ha), and trees (≥6 trees/ha) in undisturbed mature forest. • METHODS: Using six allozyme loci, we estimated the outcrossing rate (tm), the mean relatedness of progeny (rp) within and between fruits, the degree of genetic structure of pollen pools (Φft), and the effective number of pollen donors (Nep). • KEY RESULTS: The outcrossing rates reflected a strict self-incompatible species. Relatedness of progeny within fruits was similar for all populations, revealing single sires within fruits. However, relatedness of progeny between fruits within trees was consistently greater for trees in fragmented conditions across 4 yr. We found high levels of genetic structure of pollen pools in all populations with more structure in isolated trees. The effective number of pollen donors was greater for trees in undisturbed forest than in disturbed conditions. • CONCLUSIONS: Our study showed that the progeny produced by isolated trees in disturbed habitats are sired by a fraction of the diversity of pollen donors found in conserved forests. The foraging behavior of bats limits the exchange of pollen between trees, causing higher levels of progeny relatedness in isolated trees.


Asunto(s)
Ceiba/genética , Ceiba/fisiología , Ecosistema , Flujo Génico , Clima Tropical , Ceiba/clasificación , Regulación de la Expresión Génica de las Plantas , Reproducción/genética , Reproducción/fisiología
20.
Environ Technol ; 34(21-24): 3169-75, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24617076

RESUMEN

More research and development on novel oil sorbent materials is needed to protect the environmental pollution. New nonwoven fabrics (pads) of polypropylene (PP)/kapok blends (blend ratio: 100/0, 75/25, 50/50, 25/75 and 10/90) were prepared by needle punching process at a fixed (optimized) condition (punch density: 50 punches/cm2 and depth: 4mm). This study focused on the effect of blend ratio of PP/kapok nonwoven fabrics on oil sorption capacities to find the best blend ratio having the highest synergy effect. The PP/kapok blend (50/50) sample has the lowest bulk density and showed the best oil absorption capacity. The oil sorption capacity of PP/kapok blend (50/50) nonwoven fabric for kerosene/soybean oil [21.09/27.01 (g oil/g sorbent)] was 1.5-2 times higher than those of commercial PP pad oil sorbents. The highest synergy effect of PP/kapok blend (50/50) was ascribed to the lowest bulk density of PP/kapok blend (50/50), which might be due to the highest morphologically incompatibility between PP fibre and kapok. These results suggest that the PP/kapok blend (50/50) having the highest synergy effect has a high potential as a new high-performance oil sorbent material.


Asunto(s)
Ceiba/química , Fibra de Algodón , Aceites/química , Aceites/aislamiento & purificación , Polipropilenos/química , Textiles/análisis , Ultrafiltración/métodos , Adsorción , Mezclas Complejas/química , Ensayo de Materiales , Ultrafiltración/instrumentación
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