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1.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555275

RESUMO

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.


Assuntos
Antiulcerosos , Ceiba , Extratos Vegetais , Úlcera Gástrica , Animais , Humanos , Ratos , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Carragenina/efeitos adversos , Ceiba/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Úlcera
2.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432208

RESUMO

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.


Assuntos
Ceiba , Ceiba/química , Biocombustíveis , Adsorção , Carboidratos , Combustíveis Fósseis
3.
J Chromatogr A ; 1681: 463480, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36095972

RESUMO

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R2) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations.


Assuntos
Ceiba , Ceiba/química , Estudos de Viabilidade , Óleos/química , Manejo de Espécimes
4.
Artigo em Inglês | MEDLINE | ID: mdl-35270400

RESUMO

Kapok fiber (Ceiba pentandra) belongs to a group of natural fibers that are mainly composed of cellulose, lignin, pectin, and small traces of inorganic compounds. These fibers are lightweight with hollow tubular structure that is easy to process and abundant in nature. Currently, kapok fibers are used in industry as filling material for beddings, upholstery, soft toys, and nonwoven materials. However, kapok fiber has also a potential application in the adsorptive removal of heavy metal ions and dyes from aqueous systems. This study aims to provide a comprehensive review about the recent developments on kapok fiber composites including its chemical properties, wettability, and surface morphology. Effective and innovative kapok fiber composites are analyzed with the help of characterization tools such as scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and Brunauer-Emmett-Teller analysis. Different pre-treatment methods such as alkali and acid pre-treatment, oxidation pre-treatment, and Fenton reaction are discussed. These techniques are applied to enhance the hydrophilicity and to generate rougher fiber surfaces. Moreover, surface modification and synthesis of kapok fiber-based composites and its environmental applications are examined. There are various methods in the fabrication of kapok fiber composites that include chemical modification and polymerization. These procedures allow the kapok fiber composites to have higher adsorption capacities for selective heavy metal and dye removal.


Assuntos
Ceiba , Metais Pesados , Poluentes Químicos da Água , Adsorção , Ceiba/química , Corantes , Íons , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/química
5.
Carbohydr Polym ; 278: 118948, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973765

RESUMO

Creating a low-cost, highly efficient, and recyclable superabsorbent for spilled-oil cleanup is of great significance but remains a big challenge. Herein, we report a facile strategy to produce economic, environmentally friendly, and reusable foam from agricultural waste kapok fibers. These kapok-derived cellulose nanofibrils foams (KNFs) demonstrate a hierarchically porous structure at micro-level with ultra-low density (2.7 mg·cm-3). The superhydrophobic KNFs (150.5°) show outstanding oil absorption (126.8-320.4 g·g-1) and oil-water separation performance. Notably, a facile approach is designed to reuse KNFs easily by a homemade oil release system. The release behavior of the KNFs is quantitatively analyzed and confirmed by the Rigter-Peppas model, indicating that the oil release followed the Fickian diffusion. The KNFs exhibit desirable reusability, and can be recycled for at least 50 times while keeping excellent oil absorption, and release performance. These advantages prove that the KNF is a desirable substitute for spilled-oil treatment.


Assuntos
Ceiba/química , Celulose/química , Nanopartículas/química , Óleos/química , Reciclagem , Fibras de Estresse/química
6.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917541

RESUMO

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.


Assuntos
Ceiba/química , Tubérculos/química , Reologia , Amido/química , Antioxidantes/análise , Varredura Diferencial de Calorimetria , Cor , Elasticidade , Flavonoides/análise , Polifenóis/análise , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/ultraestrutura , Temperatura , Viscosidade , Difração de Raios X
7.
Oxid Med Cell Longev ; 2020: 1321354, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33101582

RESUMO

Plants are widely used in folk medicine because of their pharmacological properties. Ceiba speciosa, popularly known as paineira-rosa or tree-of-wool, is a species found in the Northwest of Rio Grande do Sul, being native of the upper Uruguay River, Brazil. The tea obtained from the stem bark is employed in folk medicine to reduce cholesterol, triacylglycerides, and glucose levels. However, there are no studies in the literature proving its efficacy or the safety of its use. For this study, we used Caenorhabditis elegans as an animal model considering its advantages for risk assessment and pharmacological screenings. For the toxicological tests, C. elegans N2 (wild type) was treated with the aqueous extract of the stem bark of C. speciosa (ECE) at the first larval stage (L1) at concentrations of 5, 25, 50, and 250 µg/mL. To evaluate biological activities, we challenged the extract for oxidative stress resistance in the presence of paraquat (0.5 mM), H2O2 (1 mM), and against glucose-induced toxicity. Our results demonstrated that ECE did not alter survival rate, pharyngeal pumping, and reproduction of the nematodes. The extract was not able to protect the nematodes against the toxicity induced by prooxidants. Notably, ECE protected against glucotoxicity by increasing worms' life span and by reducing glucose levels. On the other hand, ECE treatment did not reduce lipid accumulation induced by exogenous glucose feeding, as observed in worms which lipid droplets were tagged with GFP. Based on our results, we believe that the extract is indeed promising for further studies focusing on carbohydrates metabolism; however, it needs to be carefully evaluated since the extract does not seem to modulate lipid accumulation.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Ceiba/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Ceiba/metabolismo , Glucose/farmacologia , Larva/efeitos dos fármacos , Larva/metabolismo , Dose Letal Mediana , Longevidade/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Paraquat/toxicidade , Casca de Planta/química , Casca de Planta/metabolismo , Extratos Vegetais/química
8.
Biomed Res Int ; 2020: 3063674, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32382543

RESUMO

Postprandial hyperglycemia and oxidative stress are important factors that worsen the health condition of patients with type 2 diabetes. We recently showed that extracts from Ceiba pentandra mitigate hyperglycemia in dexamethasone- and high diet/streptozotocin-induced diabetes. Herein, we evaluated the postprandial regulatory properties and the antioxidant effects of the aqueous (AE) and methanol (ME) extracts from the stem bark of Ceiba pentandra. The phytochemical analysis of AE and ME was performed using the LC-MS technique and the total phenolic and flavonoid assays. Both extracts were tested for their ability to inhibit superoxide anion (O2 •ـ), hydrogen peroxide (H2O2), protein oxidation, alpha-amylase, and alpha-glucosidase activities. The mode of enzyme inhibition was also determined in a kinetic study. AE and ME were both rich in phenolic and flavonoid compounds. ME was 2.13 and 1.91 times more concentrated than AE in phenolic and flavonoid compounds, respectively. LC-MS allowed the identification of 5 compounds in both extracts. ME and AE inhibited O2 •ـ with IC50 of 51.81 and 34.26 µg/ml, respectively. On H2O2, they exhibited IC50 of 44.84 and 1.78 µg/ml, respectively. Finally, they exhibited IC50 of 120.60 and 140.40 µg/ml, respectively, in the inhibition of protein oxidation induced by H2O2, while showing IC50 of 39.26 and 97.95 µg/ml on the protein oxidation induced by AAPH. ME and AE inhibited alpha-amylase with IC50 of 6.15 and 54.52 µg/ml, respectively. These extracts also inhibited alpha-glucosidase, demonstrating IC50 of 76.61 and 86.49 µg/ml. AE exhibited a mixed noncompetitive inhibition on both enzymes, whereas ME exhibited a competitive inhibition on α-amylase and a pure noncompetitive inhibition on α-glucosidase. These results demonstrate that ME and AE scavenge reactive oxygen species and prevent their effects on biomolecules. Besides, ME and AE inhibit carbohydrate digestive enzymes. These properties may contribute to reduce postprandial hyperglycemia and regulate glycemia in diabetic patients.


Assuntos
Antioxidantes/química , Ceiba/química , Inibidores de Glicosídeo Hidrolases/química , Casca de Planta/química , Extratos Vegetais/química , alfa-Amilases , alfa-Glucosidases/química , Animais , Humanos , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química
9.
Fitoterapia ; 143: 104541, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32151639

RESUMO

Four flavanolignans, ceibapentains A (1) and B (2) and cinchonains Ia (3) and Ib (4), were isolated for the first time from an ethyl acetate extract of Ceiba pentandra (L) (Bombacaceae) aerial parts. The ceibapentains A (1) and B (2) are new compounds and their structures, including the absolute configurations, were determined by HRESIMS, 1D and 2D NMR, and electronic circular dichroism analyses, then compared with reported data. Compounds 1-4 were tested for their anti-Alzheimer's activity via an assessment of their inhibitory effect on amyloid ß42 aggregation using a thioflavin T assay. The results revealed that cinchonain Ia (3) showed a higher inhibitory effect (91%) than the standard curcumin (70%). Compounds 1, 2, and 4 exhibited moderate activity, with inhibition ratios of 43%, 47%, and 58%, respectively. A molecular docking study on the binding mode of 3 and curcumin with an amyloid ß1-40 peptide fibril structure indicated a high affinity of cinchonain 1a (3) towards amyloid ß1-40 peptide, in agreement with the experimental results.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Ceiba/química , Flavonolignanos/farmacologia , Fragmentos de Peptídeos/antagonistas & inibidores , Dicroísmo Circular , Egito , Flavonolignanos/isolamento & purificação , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Extratos Vegetais/química
10.
Molecules ; 25(5)2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106610

RESUMO

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.


Assuntos
Ceiba/química , Ácidos Graxos/química , Óleos de Plantas/química , Sementes/química , Antioxidantes/química , Ácidos Graxos/classificação , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
11.
Nat Prod Res ; 33(23): 3441-3444, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29792358

RESUMO

Several species of the genus Ceiba (Malvaceae) are ethnopharmacologically used. Thus, this study aimed to investigate the in vitro beneficial properties of the aqueous stem bark extract of Ceiba speciosa. The extract presented a great amount of phenolic compounds (117.4 ± 6.2 mg GAE/g). The antioxidant activity was assessed by DPPH (IC50 = 42.87 µg/mL), ORAC (2351.17 µmol TE/g) and FRAP (235.94 µM FeSO4/g) methods. In addition, the extract reduced MCF-7 cell viability as assessed by MTT. However, it prevented mitochondrial membrane depolarization and reduced caspase-9 activity induced by hydrogen peroxide. In conclusion, these findings indicate the extract is an excellent source of natural antioxidants and is able to protect ROS-induced cell death. Therefore, C. speciosa extract may possess beneficial properties for application in pharmaceutical industry as an antioxidant. However, further studies to better elucidate its mechanisms and to isolate its active compounds are required.


Assuntos
Antioxidantes/isolamento & purificação , Ceiba/química , Casca de Planta/química , Antioxidantes/química , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células MCF-7 , Malvaceae/química , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia
12.
Environ Technol ; 39(9): 1089-1095, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28463052

RESUMO

Butyl methacrylate (BMA) was grafted onto kapok fiber using benzoyl peroxide (BPO) as initiator. The structure of the grafted kapok was investigated using Fourier transform infrared spectroscopy and scanning electron microscopy. The results illustrated that BMA was successfully grafted onto the kapok fiber surface. The effects of monomer concentration, temperature and time on the oil absorbency of grafted kapok fiber were investigated. The oil absorbencies of raw kapok, NaClO2-treated kapok fiber and kapok-g-butyl methacrylate were evaluated and compared. Compared with raw kapok fiber, grafted kapok fiber showed the highest oil absorbency, with the increase percentage of 63.4%, 42.5% and 56.4% for chloroform, toluene and n-hexane, respectively. Furthermore, the as-developed grafted kapok fiber exhibited excellent reusability, and can be utilized as an eco-friendly material for recovering oil released into the surroundings.


Assuntos
Ceiba/química , Metacrilatos/química , Adsorção , Óleos , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Carbohydr Polym ; 157: 1892-1902, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-27987909

RESUMO

This research involves the rare utilisation of the kapok fibre (Ceiba pentandra) as a raw material for the fabrication of cellulose nanocrystal (CNC) and self-assembled CNC membranes. The isolation of CNC from Ceiba pentandra began with the extraction of cellulose via the chemical alkali extraction by using 5wt% NaOH, followed by the typical acidified bleaching method and, finally, the CNC production through acid hydrolysis with 60wt% H2SO4 at the optimum time of 60min. The prepared CNC was then employed for the preparation of self-assembled membrane through the water suspension casting evaporation technique. The obtained CNC membrane was characterised in terms of its composition, crystallinity, thermal stability, as well as, structural and morphological features with the use of several techniques including FTIR, XRD, AFM, TEM, FESEM, and TGA. The FESEM and AFM analyses had illustrated the achievement of a self-assembled CNC membrane with a smooth surface and a well-distributed nano-porous structure, with the porosity of 52.82±7.79%. In addition, the findings proved that the self-assembled CNC membrane displayed good adsorption capability indicated by the recorded efficiency of 79% and 85% for 10mg/L and 5mg/L of methylene blue in an aqueous solution, respectively.


Assuntos
Ceiba/química , Celulose , Membranas Artificiais , Nanopartículas , Hidrólise , Nanoporos
14.
Water Environ Res ; 88(7): 611-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27329057

RESUMO

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.


Assuntos
Antibacterianos/farmacologia , Ceiba/química , Dopamina/química , Escherichia coli/efeitos dos fármacos , Prata/química
15.
Bioresour Technol ; 211: 248-56, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27019128

RESUMO

Recently, a great attention has been paid to advanced microwave technology that can be used to markedly enhance the biodiesel production process. Ceiba pentandra Seed Oil containing high free fatty acids (FFA) was utilized as a non-edible feedstock for biodiesel production. Microwave-assisted esterification pretreatment was conducted to reduce the FFA content for promoting a high-quality product in the next step. At optimum condition, the conversion was achieved 94.43% using 2wt% of sulfuric acid as catalyst where as 20.83% conversion was attained without catalyst. The kinetics of this esterification reaction was also studied to determine the influence of factors on the rate of reaction and reaction mechanisms. The results indicated that microwave-assisted esterification was of endothermic second-order reaction with the activation energy of 53.717kJ/mol.


Assuntos
Ceiba/química , Ácidos Graxos não Esterificados , Micro-Ondas , Óleos de Plantas/química , Sementes/química , Biocombustíveis , Esterificação , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/metabolismo , Cinética
16.
J Hazard Mater ; 296: 101-111, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25913676

RESUMO

Adsorption and adhesiveness of single kapok to various oils, such as diesel, vegetable oil, used motor oil and motor oil were quantitatively evaluated by size and adhesive energy distribution of adsorbed oil droplets on fiber via drop-on-fiber micro-sorption experiments based on Carroll's theory of droplet morphology. Meanwhile, another micro polyester fiber was investigated as comparison. It was found that kapok fibers exihibited low surface energy of 40.64 mN/m with highly hydrophobicity and oil wettability. It had high water contact angle up to 151°, adsorbing four oils with average droplet size varying from emulsified state(0.1-25 µm) to dispersed state (25-100 µm). The average adhesive energies of kapok to four oils were 3.78×10(-11)-9.40×10(-11) J, with the highest for vegetable oil. Compared with kapok, polyester fiber adsorbed a large number of smaller oil droplets with their average size within emulsified state for its large specific surface area contributed by micro-fine of the fiber, but showed bad adhesiveness to retain the adsorbed oils with average droplet adhesive energy among 1.49×10(-11)-2.27×10(-11)J due to its relative higher surface energy of 59.15 mN/m. It is more suitable to be used as filter for secondary fine filtration under low inflow rate.


Assuntos
Ceiba/química , Óleos/química , Poluição por Petróleo/análise , Poluentes Químicos da Água/química , Adesividade , Adsorção , Filtração , Microscopia Eletroquímica de Varredura , Modelos Teóricos , Óleos/análise , Tamanho da Partícula , Propriedades de Superfície , Poluentes Químicos da Água/análise
17.
J Environ Sci (China) ; 27: 21-32, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25597659

RESUMO

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.


Assuntos
Ceiba/química , Poluentes Ambientais/química , Poluição Ambiental/prevenção & controle , Adsorção , Corantes/química , Metais/química , Ruído/prevenção & controle , Poluição por Petróleo/prevenção & controle
18.
Mar Pollut Bull ; 91(1): 230-7, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25528222

RESUMO

Sorption rates of kapok fibers on different oils, such as diesel, cooking oil, used motor oil, and motor oil, were quantitatively evaluated by using a wicking method. Kapok fibers absorbing different oils exhibited large differences in terms sorption coefficients. Microscopic observations of oil wetting on a single kapok showed that the four oils had varying wettability and adhesiveness to kapok, but that all of them penetrated into kapok lumens quickly because of the fiber's low surface energy, which was 40.64 mN/m, and extreme hydrophobicity, with a water contact angle up to 151°. After treatment with chloroform, there were slight changes in oil absorbencies to kapok, but the sorption coefficients for the four oils increased markedly. SEM demonstrated that chloroform treatments caused the smooth surface of the kapok fibers to become highly roughened, with densely vertical grooves that provided more available surface and a larger driving force for oil sorption through the fiber assembly.


Assuntos
Ceiba/química , Óleos/química , Petróleo , Poluentes Químicos da Água/química , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Cinética , Poluição por Petróleo , Espectroscopia de Infravermelho com Transformada de Fourier , Água
19.
Water Environ Res ; 86(4): 360-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24851332

RESUMO

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.


Assuntos
Ceiba/química , Recuperação e Remediação Ambiental/métodos , Água do Mar/química , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Absorção , Interações Hidrofóbicas e Hidrofílicas , Cinética , Termodinâmica
20.
Bioresour Technol ; 140: 10-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23672935

RESUMO

Various pretreatments on Ceiba pentandra (L.) Gaertn. (kapok) fiber prior to enzymatic hydrolysis for sugar production were optimized in this study. The optimum conditions for water, acid, and alkaline pretreatments were 170°C for 45 min, 120°C for 45 min in 1.0% (v/v) H2SO4 solution and 120°C for 60 min in 2.0% (v/v) NaOH solution, respectively. Among the three pretreatments, the alkaline pretreatment achieved the highest total glucose yield (glucose yield calculated based on the untreated fiber) (38.5%), followed by the water (35.0%) and acid (32.8%) pretreatments. As a result, the relative effectiveness of the pretreatment methods for kapok fiber was verified as alkali>water>acid at the condition stated.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Metabolismo dos Carboidratos , Carboidratos/biossíntese , Ceiba/química , Celulase/metabolismo , Etanol/metabolismo , Álcalis/farmacologia , Metabolismo dos Carboidratos/efeitos dos fármacos , Hidrólise/efeitos dos fármacos , Ácidos Sulfúricos/farmacologia , Água/farmacologia
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