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1.
ACS Omega ; 9(17): 19461-19480, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38708276

RESUMEN

Nile blue (NB) dye is a highly toxic substance that when discharged into sewage presents a significant risk to the environment and human health. Carbon-based nanomaterials, such as graphene oxide (GO), reduced graphene oxide (rGO), and their nanocomposites, offer considerable potential for eliminating hazardous pollutants from aqueous systems. In this study, we have successfully fabricated bare GO and rGO, and then, the rGO was decorated with silver (Ag) nanoparticles to develop the Ag-rGO composite. The as-prepared materials were characterized by various techniques, such as UV-visible (UV-vis) and Fourier transform infrared (FTIR) spectroscopies, X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and scanning electron microscopy (SEM) to elucidate their structure, morphology, and chemical composition. The pollutant removal performance of the as-prepared materials was evaluated through a batch approach under the effect of various experimental variables for removal of NB dye from wastewater. As obvious, the Ag-rGO composite revealed exceptional performance for NB dye removal from wastewater, with a maximum removal percentage of 94% within 60 min, which is remarkably higher than those of the rGO (i.e., 59%) and GO (i.e., 22%), under the same experimental conditions. The adsorption data was analyzed with thermodynamics, isotherms, and kinetics models to better understand the physicochemical mechanisms driving the effective removal of the NB dye. The results reveal that Ag-rGO nanocomposite exhibit excellent adsorption ability as well as favorable thermodynamic and kinetic parameters for NB dye removal. It was also found that the presence of light enhanced the adsorptive removal of NB while using Ag-rGO as an adsorbent. The present study noted significant reusability of the Ag-rGO nanocomposite, likely due to minimal Ag leaching and/or the robust stability of the Ag-rGO. It is suggested that Ag-rGO-based hybrid materials could serve as promising candidates for efficiently adsorbing and catalytically removing various toxic pollutants from wastewater.

2.
Molecules ; 28(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37175365

RESUMEN

This research work focuses on the isolation and thermo-chemical modification of cellulose and its application as an adsorbent for the removal of organic pollutants. The used cellulose was collected from a locally available plant (Olive Europa) commonly called Zaitoon. The stem branches of Zaitoon were collected and then kept in water for 40-45 days at room temperature to extract the cellulose fibers. These cellulose fibers were then kept in the Soxhlet apparatus for washing in n-hexane for 72 h. The purified cellulose was divided into three parts: one part was subjected to thermal activation (TAC), the second was modified chemically (CMC) with Benzyl Chloride, while the last one remained un-functionalized (UFC). All the three forms of cellulose were characterized via FTIR and SEM, then utilized for the removal of Titan Yellow (TY) dye from aqueous media via adsorption process by varying the contact time, temperature, concentration of dye and type, and dose of adsorbent. The adsorption efficiencies of all adsorbents were compared under different experimental variables. Thermally activated cellulose showed the best results for the removal of TY compared with other materials. The calculated removal percentage of TY was found to be 97.69, 94.83, 94.83, and 98% under equilibrium conditions of contact time, temperature, adsorbent dose, and TY concentration. Similarly, the uptake capacities of TAC under optimal experimental conditions were found to be 19.56, 18.96, 18.52, and 18.75 mg/g. Thermodynamic studies of TAC, CMC, and UFC showed that the values of ΔG are negative, while those of ΔH and ΔS are positive in all cases and at all temperatures. This indicates that the TY elimination process is endothermic and spontaneous with an entropy-driven nature. The obtained results indicate that the as-fabricated low-cost biomaterials can effectively remove dyes from wastewater through physicochemical interactions. The removal process was influenced by the nature of the adsorbent and the operating variables.


Asunto(s)
Celulosa , Contaminantes Químicos del Agua , Celulosa/química , Aguas Residuales , Adsorción , Termodinámica , Agua/química , Colorantes/química , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno
3.
J Ayub Med Coll Abbottabad ; 34(Suppl 1)(3): S707-S710, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36414596

RESUMEN

Background: Hypoadiponectinemia and raised total leukocyte count have been associated with coronary artery disease. The aim of this study was to investigate association of serum adiponectin levels with total leukocyte count in patients of coronary artery disease belonging to Khyber Pakhtunkhwa. Method: This cross-sectional/analytical study consisted of two groups. Group A contained 100 patients of coronary artery disease while group B contained 100 healthy controls. Consent of the study subjects was obtained, their history was recorded and fasting blood samples were analyzed for serum adiponectin level, total leukocyte count (TLC), serum lipid profile which included serum total cholesterol (T-C), triglyceride level (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Adiponectin level was determined with ELIZA method, TLC was estimated on automated haematology analyzer and lipid profile was determined using enzymatic colorimetric method. SPSS version 21 was used to analyze the data. Results: Subjects with coronary artery disease when compared to healthy subjects showed significantly high level of total leukocyte count (9.26±1.488 vs. 6.37±4.052) and low level of serum adiponectin (4.3±0.80 vs. 9.6±3.69). Moreover, serum lipid profile showed low HDL-C (30.04±9.1 vs. 43.64±7.3) and rose triglyceride (220.1±67.7 vs. 181.86±41.4), total cholesterol (229.3±37.01 vs. 189.4±32.7), and LDL-C (153.78±38.53 vs. 109.16±33.91) levels. Significant negative association of adiponectin with TLC (r -0.826 with p<0.01) was observed in the study subjects. Conclusion: We observed elevated level of total leukocyte count and reduced level of adiponectin in subjects with coronary artery disease. Moreover, hypoadiponectinemia correlated negatively with TLC levels.


Asunto(s)
Adiponectina , Enfermedad de la Arteria Coronaria , Humanos , LDL-Colesterol , Estudios Transversales , Triglicéridos , Recuento de Leucocitos
4.
Molecules ; 27(15)2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35956859

RESUMEN

Due to their unique layered microstructure, the presence of various functional groups at the surface, earth abundance, and attractive electrical, optical, and thermal properties, MXenes are considered promising candidates for the solution of energy- and environmental-related problems. It is seen that the energy conversion and storage capacity of MXenes can be enhanced by changing the material dimensions, chemical composition, structure, and surface chemistry. Hence, it is also essential to understand how one can easily improve the structure-property relationship from an applied point of view. In the current review, we reviewed the fabrication, properties, and potential applications of MXenes. In addition, various properties of MXenes such as structural, optical, electrical, thermal, chemical, and mechanical have been discussed. Furthermore, the potential applications of MXenes in the areas of photocatalysis, electrocatalysis, nitrogen fixation, gas sensing, cancer therapy, and supercapacitors have also been outlooked. Based on the reported works, it could easily be observed that the properties and applications of MXenes can be further enhanced by applying various modification and functionalization approaches. This review also emphasizes the recent developments and future perspectives of MXenes-based composite materials, which will greatly help scientists working in the fields of academia and material science.

5.
Crit Rev Food Sci Nutr ; 62(22): 6034-6054, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33703960

RESUMEN

Over the past decade, the gut microbiota has emerged as an important frontier in understanding the human body's homeostasis and the development of diseases. Gut flora in human beings regulates various metabolic functionalities, including enzymes, amino acid synthesis, bio-transformation of bile acid, fermentation of non-digestible carbohydrates (NDCs), generation of indoles and polyamines (PAs), and production of short-chain fatty acids (SCFAs). Among all the metabolites produced by gut microbiota, SCFAs, the final product of fermentation of dietary fibers by gut microbiota, receive lots of attention from scientists due to their pharmacological and physiological characteristics. However, the molecular mechanisms underlying the role of SCFAs in the interaction between diet, gut microbiota, and host energy metabolism is still needed in-depth research. This review highlights the recent biotechnological advances in applying SCFAs as important metabolites to treat various diseases and maintain colonic health.


Asunto(s)
Ácidos Grasos Volátiles , Microbioma Gastrointestinal , Dieta , Fibras de la Dieta , Metabolismo Energético/fisiología , Ácidos Grasos Volátiles/metabolismo , Microbioma Gastrointestinal/fisiología , Humanos
6.
J Ayub Med Coll Abbottabad ; 32(4): 531-534, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33225658

RESUMEN

BACKGROUND: Testosterone levels are shown to be affected by the social environment where individuals spend most of the duration of their daily activities. It has been reported that religion may play a role in reducing harm and contributing to the resilience of young people. Objective of the study was to compare the serum Testosterone level of the College students with that of the Madrassa students of the same age group. METHODS: This was a cross-sectional study with a total of 145 participants between 18-25 years of age. Subjects from the religious institutions (Madrassa) were 30 and non- religious institutions (Colleges) were 115. Fasting blood samples were obtained from all participants for serum testosterone levels (measured using Radioimmunoassay (RIA) technique). RESULTS: Students studying in religious institutions (Madrassa) have significantly (p=0.001) lower serum Testosterone (6.5±2.01 ng/ml) levels compared to students of the non-religious institution, i.e., 9.08±3.07 ng/ml. CONCLUSIONS: The social environment of studies like madrassa or college affects testosterone hormone levels.


Asunto(s)
Islamismo , Medio Social , Estudiantes , Testosterona/sangre , Universidades , Adolescente , Adulto , Estudios Transversales , Humanos , Masculino , Adulto Joven
7.
Asian-Australas J Anim Sci ; 33(2): 323-331, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30381752

RESUMEN

OBJECTIVE: The present work was undertaken to determine the possibility of using xanthan and guar gums as stabilizers to enhance the yogurt quality. METHODS: Purposely, yogurt was manufactured from standardized milk (3.5% fat, 8.5% solid-not-fat contents) with the addition of 2-3% starter culture. Enzyme-hydrolyzed xanthan gum (0.1%, 0.5%, 1.0%) and guar gum (0.1%, 0.5%, 1.0%) were added to the yogurt as stabilizers. Prepared yogurt samples were kept at refrigeration temperature (4±2°C) for 21 days and various quality and sensory parameters were studied at regular intervals (7 days). RESULTS: Results showed that yogurt with 0.5% xanthan gum (T5) was best in terms of preventing syneresis and improving the viscosity, water holding capacity and texture of the product. Additionally, adding gums did not adversely affect the sensorial attributes of the product. CONCLUSION: So, yogurt containing modified gums was found useful in augmenting the product quality and therefore addition of gums is highly recommended for manufacturing yogurt.

8.
Mol Biol Rep ; 46(4): 4565-4580, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31243724

RESUMEN

Polysaccharides including resistant starch are categorized as dietary fiber and are used as an important prebiotic. Similar to soluble fibers, resistant starch also has a number of physiological effects that have been shown to be beneficial for health. Starch hydrolyzing enzymes, most importantly amylases, play essential roles in the production of resistant starch. This study aimed to develop α-amylase-treated maize flour with slow digestibility and unique physicochemical characteristics compared to native maize flour. In the current study, resistant starch type III from maize flour was prepared using α-amylase obtained from indigenously isolated Bacillus licheniformis. The α-amylase gene from B. licheniformis was amplified and cloned into the pET-24(a) vector, expressed in E. coli BL21 (DE3) cells and purified by metal ion affinity chromatography. The purified enzyme enhanced the yield of resistant starch 16-fold in maize flour. Scanning electron microscopy revealed that the granular structure of maize flour was disrupted into a dense network with irregular structure, and X-ray diffractograms confirmed the transformation from an amorphous to a crystalline structure upon α-amylase treatment. Thermogravimetric analysis revealed increased amylose content of α-amylase-treated maize flour. Moreover, α-amylase-treated maize flour resulted in a significant enhancement of the desired properties of maize flour, such as resistant starch content, amylose, milk absorption capacity, and iodine and fatty acid complexing ability, and a reduction in swelling power, water binding, oil absorption capacity, and in vitro digestibility compared to untreated maize flour. Resistant starch type III showed low digestibility and increased complexing ability with iodine and fatty acid and therefore could be a safe and beneficial alternative as a coating material for the delivery of active, sensitive ingredients to the colon.


Asunto(s)
Almidón/biosíntesis , Zea mays/metabolismo , alfa-Amilasas/metabolismo , Amilosa , Bacillus licheniformis/enzimología , Bacillus licheniformis/metabolismo , Harina , Hidrólisis , Polisacáridos/química , alfa-Amilasas/genética
9.
PeerJ ; 6: e5376, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30123708

RESUMEN

BACKGROUND: Use of traditional methods for determining meat spoilage is quite laborious and time consuming. Therefore, alternative approaches are needed that can predict the spoilage of meat in a rapid, non-invasive and more elaborative way. In this regard, the spectroscopic techniques have shown their potential for predicting the microbial spoilage of meat-based products. Consequently, the present work was aimed to demonstrate the competence of Fourier transform infrared spectroscopy (FTIR) to detect spoilage in chicken fillets stored under aerobic refrigerated conditions. METHODS: This study was conducted under controlled randomized design (CRD). Chicken samples were stored for 8 days at 4 + 0.5 °C and FTIR spectra were collected at regular intervals (after every 2 days) directly from the sample surface using attenuated total reflectance during the study period. Additionally, total plate count (TPC), Entetobacteriaceae count, pH, CTn (Color transmittance number) color analysis, TVBN (total volatile basic nitrogen) contents, and shear force values were also measured through traditional approaches. FTIR spectral data were interpreted through principal component analysis (PCA) and partial least square (PLS) regression and compared with results of traditional methods for precise estimation of spoilage. RESULTS: Results of TPC (3.04-8.20 CFU/cm2), Entetobacteriaceae counts (2.39-6.33 CFU/cm2), pH (4.65-7.05), color (57.00-142.00 CTn), TVBN values (6.72-33.60 mg/100 g) and shear force values (8.99-39.23) were measured through traditional methods and compared with FTIR spectral data. Analysis of variance (ANOVA) was applied on data obtained through microbial and quality analyses and results revealed significant changes (P < 0.05) in the values of microbial load and quality parameters of chicken fillets during the storage. FTIR spectra were collected and PCA was applied to illuminate the wavenumbers potentially correlated to the spoilage of meat. PLS regression analysis permitted the estimates of microbial spoilage and quality parameters from the spectra with a fit of R2 = 0.66 for TPC, R2 = 0.52 for Entetobacteriaceae numbers and R2 = 0.56 for TVBN analysis of stored broiler meat. DISCUSSION: PLS regression was applied for quantitative interpretation of spectra, which allowed estimates of microbial loads on chicken surfaces during the storage period. The results suggest that FTIR spectra retain information regarding the spoilage of poultry meat. CONCLUSION: The present work concluded that FTIR spectroscopy coupled with multivariate analysis can be successfully used for quantitative determination of poultry meat spoilage.

10.
J Food Sci Technol ; 53(1): 19-30, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26787929

RESUMEN

Globally, the demand for safe, healthy and nutritious meat and allied products possesses improved taste with extended shelf life is mounting. Microbial safety is among the imperative challenges that prevails in meat products because they provide an ideal medium for the growth of microorganisms particularly pathogenic bacteria. The incidence of these microbes can result quality deterioration of products leading towards food borne diseases when consumed by peoples. Several preservation technologies like chemical and biological interventions are effective to retard or inactivate the growth of micro-organisms most commonly related to food-borne diseases. Despite these, innovative approaches like hydrostatic pressure processing, active packaging, pulse electric field, hurdle approach and use of natural antimicrobials can be deployed to enhance the safety of meat and meat products. The objective of review is to describe the current approaches and developing technologies for enhancing safety of meat and allied meat products.

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