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1.
J Food Sci Technol ; 58(11): 4391-4402, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34538922

RESUMO

Marama root is known to be the major source of nutrition for the first settlers (the Herero, Tswana and Khoisan people) of Sub-Sahara Africa, but it is not yet domesticated. The potential of Marama (Tylosema esculentum) root in food and nutrition security may pave way for the domestication of the plant in Sub-Saharan Africa. Marama storage roots collected from two locations, Omipanda and Okomumbonde in Namibia were analysed and compared to commercial potato and waxy potato tuber as well as sweet potato root. Fresh weight (FW) marama roots had mean water content, crude protein, fat, ash, and starch content of about 866, 24, 2, 22, and 56 g/kg root, respectively. Marama root showed higher total soluble solids (4.3°) compared to potato, waxy potato and sweet potato. The swelling index (3 g/g) and water absorption capacity (1.5 g/g) of marama root were close to those of sweet potato, but lower than those of the potato and waxy potato. The soluble and insoluble dietary fibre of marama root (4.8, and 15%, db, respectively) were higher than those of the commercial potatoes; and the in vitro- starch digestibility of marama root was close to those of potatoes. Marama root has potential as prebiotic and its food value is similar to sweet potato in functional properties and nutritional composition. The high soluble solids of marama root can enhance the energy density of complimentary food, but will require compositing with high protein legume flour. There is a prospect of a protein-energy dense composite flour from a blend of the bean and root.

2.
Int J Biol Macromol ; 222(Pt B): 2888-2921, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36240888

RESUMO

Freshwater scarcity is one of the world's foremost environmental stress concerns. In the last few years, with sustainable industrial growth and rapidly growing population, the problem of freshwater shortage has encouraged researchers to conduct comprehensive research for the development of advanced water harvesting and wastewater treatment techniques. Natural gums-based hydrogels have been widely used in different water purification and harvesting applications because of their environment friendly nature, high water absorption, adsorption and retention capacities. In this article, we presented an entirely conceptual and critical review of literature mainly focused on the potential of different natural gums-based hydrogel in water harvesting and wastewater treatment applications. First, different categories of natural gums-based hydrogels including stimuli responsive hydrogels, physically and chemically crosslinked hydrogels, were introduced. Then, the emphasis was given on the role of natural gums-based hydrogels in different wastewater treatment applications like adsorption, photocatalysis and flocculation. After that, the latest research progress on the use of natural gums-based hydrogels in atmospheric water harvesting and seawater desalination was discussed. Finally, different challenges and main limitations associated with the use of natural gums-hydrogels in water purification and harvesting applications were discussed to understand the research gaps and drawbacks which need improvements.


Assuntos
Hidrogéis , Purificação da Água , Água , Purificação da Água/métodos , Águas Residuárias , Adsorção
3.
Chemosphere ; 289: 133100, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34843837

RESUMO

Rapid industrial development is associated with high discharge of toxic pollutants into the environment. The industries discharge their wastewater containing organic pollutants directly into the water system without treating them that has posed many serious threats to environmental protection. The use of bioadsorbents for the removal of such toxic pollutants from the waste water due to its simple synthesis, easy operation, effectiveness, and economic viability have emerged a new dimension in the wastewater treatment approaches. Various adsorbents have been prepared to examine their adsorption capacity against different adsorbates, but, to attain sustainability, biocompatibility, and biodegradation, bio-adsorbents have been found to won the battle. Seaweed derived polysaccharide; Carrageenan (CR) has been proven to be an excellent adsorbent for the wastewater treatment. It has been successfully modified with various components to form CR based-magnetic composites, hydrogels, nanoparticle modified CR composites and many others to enrich and diversify its properties. In this review, we have explained the adsorption behaviour of various carrageenan based adsorbents for the removal of different dyes. The influence of various parameters such as the effect of initial concentration, adsorbent dosage, contact time, pH, temperature, and ion concentration on dye adsorption is well explained. This paper also summarizes the structure, morphology, swelling ability, and thermal stability of carrageenan. The data also expounds on the adsorption capacity, kinetic model, isotherm model, and nature of the adsorption process. Different types of solvents are used for the regeneration and reusability of carrageenan adsorbents and their regeneration studies and desorption efficiency is well-explained. The adsorption mechanism of dyes onto carrageenan based adsorbents has been well described in this review. This review provides a deep insight about the use of carrageenan based adsorbents for the wastewater treatment.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Adsorção , Carragenina , Concentração de Íons de Hidrogênio , Cinética , Águas Residuárias , Poluentes Químicos da Água/análise
4.
Chemosphere ; 291(Pt 1): 132862, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34774612

RESUMO

In this article, the nickel (Ni2+) ions removal from the wastewater is reviewed. Adsorption is widely used to remove Ni2+ ions from waters and wastewaters. The usage of biomass is becoming more common for Ni2+ ions removal, while the commercial activated carbon from different agriculture wastes is preferred as an adsorbent for Ni2+ ion removal. The present review aimed to organise the available information regarding sustainable approaches for Ni2+ ions removal from water and wastewaters. These include adsorption by nanoparticles, bacterial biomass, and activated carbon from agriculture wastes, since they are the most common used for the Ni2+ ions removal. The bacterial and agricultural waste adsorbents exhibited high efficiency with a renewable source of biomass for Ni2+ ion removal. The biosorption capacity of the Ni2+ ions by the bacterial biomass range from 5.7 to 556 mg/g, while ranging from 5.8 to 150 mg/g by the activated carbon from different organic materials. The biosorption capacity of the nanocomposite adsorbents might reach to 400 mg/g. It appeared that the elimination of nickel ions need a selective biomass adsorbent such as the tolerant bacterial cells biomass which acts as a store for Ni2+ ion accumulations as a results for the active and passive transportation of the Ni2+ ions through the bacterial cell membrane.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Níquel , Águas Residuárias
5.
Chemosphere ; 289: 133243, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34896417

RESUMO

Dual functional innovative approaches were developed to tackle the algal scum problem in water by utilizing the algal (Spirogyra sp.) biomass waste for organic dye-laden industrial wastewater treatment, a global problem, and challenge. Therefore, an algal biochar-based nanocomposite (nAgBC) was synthesized and employed as a low-cost adsorbent for Congo red (CR) removal. Surface morphology, physicochemical characteristics, elemental composition, phase, and stability of the nanocomposite was analyzed using BET, FESEM-EDX, FTIR, XRD, XPS, and TGA. The nanocomposite was found to be thermostable, mesoporous with large and heterogeneous surface area, containing nAg as doped material, where -OH, NH, CO, CC, SO, and CH are the surface binding active functional groups. Maximum adsorption efficiency of 95.92% (18 mg L-1 CR) was achieved (qe = 34.53 mg g-1) with 0.5 g L-1 of nanocomposite after 60 min, at room temperature (300 K) at pH 6. Isotherm and kinetic model suggested multilayer chemisorption, where adsorption thermodynamics indicated spontaneous reaction. Fluorescens spectral analysis of CR confirmed the formation of CR supramolecule, supporting enhanced adsorption. Furthermore, the result suggested a 5th cycle reusability and considerable efficacy towards real textile industrial effluents. Synergistic effects of the active surface functional groups of the biochar and nAg, along with the overall surface charge of the composite lead to chemisorption, electrostatic attraction, H-bonding, and surface complexation with CR molecules. Thus, synthesized nAgBC can be applicable to mitigate the wastewater for cleaner production and environment.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Biomassa , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Águas Residuárias , Poluentes Químicos da Água/análise
6.
Cureus ; 14(12): e32465, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36644080

RESUMO

The gut microbiome helps maintain homeostasis in the body, but what if the gut experiences imbalance? It would lead to dysbiosis - which is involved in multiple diseases, including but not limited to cardiovascular diseases, the most common cause of mortality around the globe. This research paper aims to explain all the possible mechanisms known linking the gut microbiome to the contribution of worsening cardiovascular events. PubMed and Google Scholar were thoroughly explored to learn the role of the gut microbiome in cardiovascular events. A systematic review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to analyze the possible pathways and the metabolites included in the study. Thirteen review articles were selected based on the assessment of multiple systematic reviews (AMSTAR) and the scale for the assessment of non-systematic review articles (SANRA) checklist scores. In this article, we have discussed the role of the gut microbiome in atherosclerosis, hypertension, metabolic disorders such as diabetes and obesity, coronary artery disease, etc. Various pathways to modify the gut microbiome are also discussed, along with the use of probiotics. Finally, we discussed the role of trimethylamine N-oxide (TMAO), a gut microbiome metabolite, as a biomarker for the prognosis of various diseases. This study concluded that the gut microbiome does play a crucial role in the worsening of cardiovascular diseases and the metabolites of which can be used as biomarkers in the prognosis of cardiovascular events.

7.
Chemosphere ; 285: 131373, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34265718

RESUMO

Millions of litters of multifarious wastewater are directly disposed into the environment annually to reduce the processing costs leading to eutrophication and destroying the clean water sources. The bioelectrochemical systems (BESs) have recently received significant attention from researchers due to their ability to convert waste into energy and their high efficiency of wastewater treatment. However, most of the performed researches of the BESs have focused on energy generation, which created a literature gap on the utilization of BESs for wastewater treatment. The review highlights this gap from various aspects, including the BESs trends, fundamentals, applications, and mechanisms. A different review approach has followed in the present work using a bibliometric review (BR) which defined the literature gap of BESs publications in the degradation process section and linked the systematic review (SR) with it to prove and review the finding systematically. The degradation mechanisms of the BESs have been illustrated comprehensively in the current work, and various suggestions have been provided for supporting future studies and cooperation.


Assuntos
Fontes de Energia Bioelétrica , Purificação da Água , Eletrodos , Águas Residuárias , Água
8.
Cureus ; 13(10): e18901, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34692267

RESUMO

More than a century after its introduction, appendectomy has remained the gold standard treatment for acute appendicitis. In adults with acute uncomplicated appendicitis, nonoperative management (NOM) has been shown to be a viable treatment option. To date, there has been relatively limited data on the nonoperative management of acute appendicitis in the pediatric population. The primary objective of this study was to systematically review the available literature in the pediatric population and compare the efficacy and recurrence between initial nonoperative treatment strategy and appendectomy in children with uncomplicated appendicitis. In July 2021, we conducted systematic searches of the PubMed and Google Scholar databases. We only included full-text comparative original studies published within the last decade, and we excluded articles that solely examined NOM without comparing it to appendectomy. Two writers worked independently on the data collection and analysis. It was found that NOM had a high initial success rate and a low rate of recurrent appendicitis. After months of follow-up, the vast majority of patients with uncomplicated acute appendicitis who received initial nonoperative treatment did not require surgical intervention. Furthermore, the rate of complication was comparable in both treatment groups, and NOM did not appear to be associated with an increased risk of complications. The most significant drawback stemmed from the fact that the included articles in this study had a wide range of study designs and inclusion criteria. According to current evidence, NOM is feasible and cost-effective. Antibiotic therapy can be given safely in a small subset of individuals with uncomplicated appendicitis. To optimize outcomes, physicians should evaluate the clinical presentation and the patient's desire when selecting those to be managed nonoperatively. Again, more research, preferably large randomized trials, is required to compare the long-term clinical efficacy of NOM with appendicectomy. Finally, additional research is required to establish the characteristics of patients who are the best candidates for nonoperative treatment.

9.
Carbohydr Polym ; 240: 116291, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475572

RESUMO

The effect of modification with phenolic extracts from grape pomace (GPE) and sorghum bran (SBE) under alkaline conditions for 6 and 12 h, with and without washing with aqueous ethanol (post modification) on the enzymatic hydrolysis as measured by viscosity decrease and antioxidant activity of maize starch was studied. Phenolic-modified starches showed lower rate of starch hydrolysis. The DSC of residues after enzyme hydrolysis showed the conversion of type I inclusion complexes in the unwashed to type II inclusion complexes in the washed phenolic-modified starches. FTIR suggests the presence of covalent bonds in the residues of the phenolic-modified starches due to the retention of starch-bound phenolics. Phenolic-modified starches showed ABTS radical scavenging activity. Ultra-fast liquid chromatography showed polymerisation of monomeric and dimeric procyanidins to oligomeric procyanidins in GPE and SBE-modified starches. It can be concluded that phenolic-modified starches with relatively low hydrolysis and antioxidant activity can be produced under alkaline conditions.


Assuntos
Antioxidantes/química , Fenóis/química , Extratos Vegetais/química , Sorghum , Amido/química , Vitis , Benzotiazóis/química , Grão Comestível , Concentração de Íons de Hidrogênio , Hidrólise , Fenóis/análise , Ácidos Sulfônicos/química
10.
Carbohydr Polym ; 212: 352-360, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30832867

RESUMO

This study determines the effects of stearic acid and gamma irradiation, alone and in combination, on properties of amylose-lipid nanomaterials from pasted high amylose maize starch (HAMS) with and without alpha amylase hydrolysis. HAMS was incorporated with stearic acid (0, 1.5% and 5%, w/w), irradiated at 0, 30 and 60 kGy and pasted under pressure in a rheometer. Isolated materials after thermostable alpha amylase or hot water washing were freeze-dried and characterised using differential scanning calorimetry (DSC), X-ray diffraction (XRD), Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). The isolated materials contain amylose-lipid complexes (ALCs) as determined by DSC and XRD. Pasting of gamma irradiated HAMS produced type I ALCs, whereas that for un-irradiated HAMS produced type II ALCs. The ALCs occurred at nanoscale with sizes ranging from 10 to 110 nm as observed with AFM and TEM. Tailor-made ALCs nanomaterials can be produced from HAMS (with and without added stearic acid).


Assuntos
Amilose/efeitos da radiação , Lipídeos/efeitos da radiação , Nanoestruturas/efeitos da radiação , Amido/efeitos da radiação , Ácidos Esteáricos/efeitos da radiação , Zea mays/efeitos da radiação , Amilose/química , Varredura Diferencial de Calorimetria/métodos , Raios gama , Lipídeos/química , Nanoestruturas/química , Amido/química , Ácidos Esteáricos/química , Difração de Raios X/métodos
11.
Foods ; 8(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234403

RESUMO

Child malnutrition remains a major public health problem in low-income African communities, caused by factors including the low nutritional value of indigenous/local complementary porridges (CP) fed to infants and young children. Most African children subsist on locally available starchy foods, whose oral texture is not well-characterized in relation to their sensorimotor readiness. The sensory quality of CP affects oral processing (OP) abilities in infants and young children. Unsuitable oral texture limits nutrient intake, leading to protein-energy malnutrition. The perception of the oral texture of selected African CPs (n = 13, Maize, Sorghum, Cassava, Orange-fleshed sweet potato (OFSP), Cowpea, and Bambara) was investigated by a trained temporal-check-all-that-apply (TCATA) panel (n = 10), alongside selected commercial porridges (n = 19). A simulated OP method (Up-Down mouth movements- munching) and a control method (lateral mouth movements- normal adult-like chewing) were used. TCATA results showed that Maize, Cassava, and Sorghum porridges were initially too thick, sticky, slimy, and pasty, and also at the end not easy to swallow even at low solids content-especially by the Up-Down method. These attributes make CPs difficult to ingest for infants given their limited OP abilities, thus, leading to limited nutrient intake, and this can contribute to malnutrition. Methods to improve the texture properties of indigenous CPs are needed to optimize infant nutrient intake.

12.
Food Chem ; 297: 124879, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253268

RESUMO

This study determined the effects of phenolic extracts from grape pomace and sorghum bran, reaction time and washing with aqueous ethanol on the pasting, flow, thermal and molecular properties of maize starch. The starch modification was carried out under alkaline conditions. The phenolic extracts increased the peak viscosity of the starch. Reaction time had no significant effect on starch properties. Washing with aqueous ethanol significantly increased the peak, final, and setback viscosities of the phenolic modified maize starches. DSC of phenolic modified starches showed higher enthalpy (ΔH) before and after washing with aqueous ethanol in comparison with starch without phenolic extract. FTIR spectra suggested the possible formation of hydrogen and ether (covalent) bonds between starch and phenolic compounds. It can be concluded that the pasting, flow and thermal properties of maize starch can be modified with phenolic extract under alkaline conditions to produce "clean label" starch-phenolic complex.


Assuntos
Fenóis/química , Extratos Vegetais/química , Sorghum/química , Amido/química , Vitis/química , Zea mays/metabolismo , Liofilização , Concentração de Íons de Hidrogênio , Sorghum/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise , Temperatura , Termodinâmica , Viscosidade , Vitis/metabolismo
13.
Carbohydr Polym ; 168: 86-93, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28457467

RESUMO

Nanoparticles were isolated from tef and maize starch modified with added stearic acid after pasting at 90°C for 130min. This was followed by thermo-stable alpha-amylase hydrolysis of the paste. The resultant residues were then characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic laser scattering particle size distribution (DLPSD), atomic force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM). XRD and DSC showed that the isolated residues consisted of amylose-lipid complexes. These complexes were type II with melting temperature above 104°C. DLPSD, AFM and HRTEM showed that the isolated tef and maize starch residues consisted of nanoparticles which became more distinct with increased hydrolysis time. The isolated tef and maize nanoparticles had distinct particles of about 3-10nm and 2.4-6.7nm, respectively and the yield was about 24-30%. The results demonstrated that distinct (physically separate) nanoparticles of less than 10nm can be isolated after formation during pasting of tef and maize starch with stearic acid. The production and isolation of the nanoparticles uses green chemistry principles and these nanoparticles can be used in food and non-food systems as nanofillers.

14.
Food Chem ; 190: 12-19, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26212935

RESUMO

The effects of stearic acid and gamma irradiation on pasting properties of high amylose maize starch (HAMS) were studied. Stearic acid (0%, 1.5%, and 5%) was added to HAMS, and then irradiated at 0, 30, and 60 kGy before pasting. Stearic acid increased the paste viscosity of un-irradiated HAMS from 420 mPas to 557 and 652 mPas for 1.5% and 5% stearic acid, respectively. This observation related well with the formation of type II amylose-lipid complexes, with melting temperatures of about 100-120 °C. Gamma irradiation (30 and 6 0kGy) reduced pasting viscosity of HAMS. Pasting of gamma irradiated HAMS resulted in the formation of type I amylose-lipid complexes, with melting temperatures and enthalpies ranging from 82 to 102 °C and 0.22 to 1.85 J/g, respectively. Stearic acid addition followed by irradiation creates means of producing different types of amylose-lipid complexes from HAMS for industrial utilization.


Assuntos
Amilose/metabolismo , Amido/metabolismo , Ácidos Esteáricos/metabolismo , Zea mays/metabolismo , Raios gama
15.
J Int Assoc Provid AIDS Care ; 13(6): 506-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24522763

RESUMO

This cross-sectional study approached emergency department (ED) patients after the treating physician's disposition decision to measure patient understanding of whether or not they had received an HIV test during their ED encounter. Of the 300 respondents, 24 were excluded due to missing data or because they had received an ED HIV test. Mean age was 41 years, 51% were men, 61% were black, and 29% had no high school degree. There were 5.8% (95% confidence interval: 3.5%-9.4%) who erroneously reported HIV test delivery during their ED course. Our results suggest a small but significant minority of patients falsely assume that they have been tested for HIV during their ED visit. This misperception could have broad implications, leading to less frequent subsequent testing, false reassurance of HIV-negative status, and inaccuracies in surveillance estimates or surveys that depend on self-report.


Assuntos
Comunicação , Serviço Hospitalar de Emergência , Infecções por HIV/diagnóstico , Programas de Rastreamento , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Estudos Transversais , Feminino , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino
16.
Drug Dev Ind Pharm ; 29(3): 253-65, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12741607

RESUMO

A vigorous research effort has been undertaken worldwide to replace injectable insulin by a more comfortable and painless delivery method. Several routes have been explored for their suitability with respect to insulin degradation in the human body. Considerable progress has been made in achieving the common goal for a convenient and equally effective insulin delivery. This article reviews the different routes available for insulin administration and the many successful developments that have been made in recent years for improving that particular route for a much better insulin delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Vias de Administração de Medicamentos , Humanos , Tecnologia Farmacêutica
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