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1.
Nanotechnology ; 35(29)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38631335

RESUMO

Most of the applied research on BiFeO3(BFO) focuses on magnetoelectric and spintronic applications. This calls for a detailed grasp of multiferroic and conduction properties. BFO thin films with (100) epitaxial growth has been deposited on a LaNiO3(LNO) buffered Pt/Ti/SiO2/Si(100) substrate using RF magnetron sputtering. The film formed at 15 mTorr, 570 °C, and with Ar/O24:1 had a reasonably high degree of (100)-preferential orientation, the least surface roughness, and a densely packed structure. We obtained ferroelectric loops with strong polarization (150µC cm-2). The leakage current density is as low as 10-2A cm-2at 100 kV cm-1, implying that space-charge-limited bulk conduction (SCLC) was the primary conduction channel for carriers within BFO films. Local electrical conduction behavior demonstrates that at lower voltages, the grain boundary dominates electrical conduction and is linked to the displacement of oxygen vacancies in the grain boundary under external electric fields. We hope that a deeper understanding of the conduction mechanism will help integrate BFO into viable technologies.

2.
Nanotechnology ; 35(30)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38653208

RESUMO

Carbon-based electrode materials have widely been used in supercapacitors. Unfortunately, the fabrication of the supercapacitors includes a polymeric binding material that leads to an undesirable addition of weight along with an increased charge transfer resistance. Herein, binder-free and lightweight electrodes were fabricated using powder processing of carbon nanofibers (CNFs) and graphene nanoplatelets (GNPs) resulting in a hybrid all-carbon composite material. The structural, morphological, and electrochemical properties of the composite electrodes were studied at different concentrations of GNPs. The specific capacitance (Cs) of the CNFs/GNPs composite was improved by increasing the concentration of GNPs. A maximum Cs of around 120 F g-1was achieved at 90 wt% GNPs which is around 5-fold higher in value than the pristine CNFs in 1 M potassium hydroxides (KOH), which then further increased to 189 F g-1in 6 M KOH electrolyte. The energy density of around 20 Wh kg-1with the corresponding power density of 340 W kg-1was achieved in the supercapacitor containing 90 wt% GNPs. The enhanced electrochemical performance of the composite is related to the presence of a synergistic effect and the CNFs establishing conductive/percolating networks. Such binder-free all-carbon electrodes can be a potential candidate for next-generation energy applications.

3.
Phys Chem Chem Phys ; 26(13): 10168-10182, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38495023

RESUMO

The innovative design of thin, multiphase flexible composite systems with good mechanical properties, low density and improved EMI shielding properties at low filler content has become a key area of research. In this work, we report the low temperature synthesis of three-dimensional ternary composites (PANI/NFO@CNTs and PANI/NFO@RGO) by oxidative chemical polymerization of aniline in the presence of two different binary composites, viz. NFO@CNTs and NFO@RGO. Enhanced impedance matching is achieved by varying the ratio of the carbon allotropes (CNTs and RGO) to the ferrite component. The synthesis of NFO, PANI/NFO@CNTs and PANI/NFO@RGO is validated by XRD and FTIR spectroscopy. Field emission scanning electron microscopy (FE-SEM) confirmed the synthesis of core-shell structures of PANI/NFO@CNTs and PANI/NFO@RGO, where the binary composites (NFO@CNTs and NFO@RGO) serve as a core onto which a tubular PANI layer was coated. Shielding effectiveness of 22.36 dB (99.41% attenuation) is exhibited by the ternary composite PANI/NFO@CNTs (8 : 1), while for PANI/NFO@RGO (20 : 1) a total shielding effectiveness of 31 dB equivalent to 99.92% attenuation was observed at a thickness of 2 mm. The ternary composite PANI/NFO@RGO (20 : 1) 4 mm showed a maximum SET of 43 dB corresponding to 99.996% attenuation of incident EM waves. The enhanced EMI shielding properties of the synthesized ternary composite systems are accredited to good impedance matching, effective dielectric and magnetic loss mechanisms and good conductivity, which facilitate multiple reflections and scattering of incident radiation.

4.
Molecules ; 28(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37894509

RESUMO

Starches from different botanical sources are affected in the presence of enzymes. This study investigated the impact of α-amylase on several properties of pre-gelatinized starches derived from chickpea (Cicer arietinum L.), wheat (Triticum aestivum L.), corn (Zea mays L.), white beans (Phaseolus vulgaris), and sweet potatoes (Ipomoea batatas L.). Specifically, the water holding capacity, freezable water content, sugar content, and water sorption isotherm (adsorption and desorption) properties were examined. The source of α-amylase utilized in this study was a germinated sorghum (Sorghum bicolor L. Moench) extract (GSE). The starch samples were subjected to annealing at temperatures of 40, 50, and 60 °C for durations of either 30 or 60 min prior to the process of gelatinization. A significant increase in the annealing temperature and GSE resulted in a notable enhancement in both the water-holding capacity and the sugar content of the starch. The ordering of starches in terms of their freezable water content is as follows: Chickpea starch (C.P.S) > white beans starch (W.B.S) > wheat starch (W.S) > chickpea starch (C.S) > sweet potato starch (S.P.S). The Guggenheim-Anderson-de Boer (GAB) model was only employed for fitting the data, as the Brunauer-Emmett-Teller (BET) model had a low root mean square error (RMSE). The application of annealing and GSE treatment resulted in a shift of the adsorption and desorption isotherms towards greater levels of moisture content. A strong hysteresis was found in the adsorption and desorption curves, notably within the water activity range of 0.6 to 0.8. The GSE treatment and longer annealing time had an impact on the monolayer water content (mo), as well as the C and K parameters of the GAB model, irrespective of the annealing temperature. These results can be used to evaluate the applicability of starch in the pharmaceutical and food sectors.


Assuntos
Ipomoea batatas , Sorghum , Grão Comestível , Amilose , Amido , alfa-Amilases , Água , Açúcares , Extratos Vegetais
5.
Molecules ; 27(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35630544

RESUMO

The influence of 2% and 5% Cordia (CG) and Ziziphus (ZG) gums on dough characteristics and cookie quality was investigated. Micro-DoughLab, a texture analyzer (TA), a rapid viscoanalyzer (RVA), and solvent retention capacity were used to examine the effect of CG and ZG gums on dough physicochemical parameters (SRC) and cookie quality. The diameter, thickness, spread, and sensory evaluation of cookies were evaluated. With the addition of CG and ZG, dough softness, mixing time, and mixing tolerance index (MTI) increased, whereas stability and water absorption decreased. TA data showed that adding gums resulted in softer and less sticky doughs than the control, whereas RVA data showed that adding CG resulted in a significant increase in peak viscosity, but no change in flour gel setback. In comparison to the control and CG samples, the ZG samples exhibited the most dough extensibility. The thickness and diameter of the cookies increased but the spread decreased, due to the added gums. The gum-containing cookies had a lower overall acceptability by panelists than the control, although only by a small margin. Gum-containing cookies, on the other hand, can deliver up to 5% soluble fiber.


Assuntos
Cordia , Ziziphus , Fenômenos Químicos , Farinha , Reologia
6.
Molecules ; 27(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163967

RESUMO

This study was planned to explore the locally available natural sources of gum hydrocolloids as a natural modifier of different starch properties. Corn (CS), sweet potato (SPS), and Turkish bean (TBS) starches were mixed with locally extracted native or acetylated cactus (CG) and acacia (AG) gums at 2 and 5% replacement levels. The binary mixtures (starch-gums) were prepared in water, freeze dried, ground to powder, and stored airtight. A rapid viscoanalyzer (RVA), differential scanning calorimeter (DSC), texture analyzer, and dynamic rheometer were used to explore their pasting, thermal, textural, and rheological properties. The presence of acetylated AG or CG increased the final viscosity (FV) in all three starches when compared to starch pastes containing native gums. Plain SPS dispersion had a higher pasting temperature (PT) than CS and TBS. The addition of AG or CG increased the PT of CS, SPS, and TBS. The thermograms revealed the overall enthalpy change of the starch and gum blends: TBS > SPS > CS. The peak temperature (Tp) of starches increased with increasing gum concentration from 2 to 5% for both AG and CG native and modified gums. When compared to the control gels, the addition of 2% CG, either native or modified, reduced the syneresis of starch gels. However, further addition (5% CG) increased the gels' syneresis. Furthermore, the syneresis for the first cycle on the fourth day was higher than the second cycle on the eighth day for all starches. The addition of native and acetylated CG reduced the hardness of starch gels at all concentrations tested. All of the starch dispersions had higher G' than G″ values, indicating that they were more elastic and less viscous with or without the gums. The apparent viscosity of all starch gels decreased as shear was increased, with profiles indicating time-dependent thixotropic behavior. All of the starch gels, with or without gums, showed a non-Newtonian shear thinning trend in the shear stress vs. shear rate graphs. The addition of acetylated CG gum to CS resulted in a higher activation energy (Ea) than the native counterparts and the control. More specifically, starch gels with a higher gum concentration (5%) provided greater Ea than their native counterparts.


Assuntos
Fabaceae/metabolismo , Ipomoea batatas/metabolismo , Zea mays/metabolismo , Acacia , Coloides , Fabaceae/crescimento & desenvolvimento , Goma Arábica/metabolismo , Ipomoea batatas/crescimento & desenvolvimento , Opuntia/metabolismo , Gomas Vegetais , Reologia/métodos , Arábia Saudita , Amido/metabolismo , Temperatura , Termodinâmica , Viscosidade , Zea mays/crescimento & desenvolvimento
7.
Molecules ; 28(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36615198

RESUMO

The effectiveness of hydrocolloids (2% maximum in various combinations) from various sources, including maltodextrins (MD) with polymerization degree (DP) 18 and ziziphus gum (ZG), on the dough properties and quality of panned bread, as well as the possibility of using them to delay the bread staling process, have been investigated after 24, 72, and 96 h of storage. By evaluating the pasting capabilities of wheat flour slurry, dough properties, and the final product, the effects of the ziziphus gum (ZG) and maltodextrins (MD) were ascertained. A TA-TXT texture analyzer, a texture profile analysis test, and Micro-doughLab were used to evaluate the dough mixing properties. Additionally, a hedonic sensory evaluation of the overall acceptance of the bread, as well as its texture, aroma, taste, and color, was done. It is clear that MD had a more distinct impact than ZG on the way dough was mixed, the texture of the gel, and the finished product. The combination of MD and ZG significantly altered the bread's physical characteristics and its aging over time. The decreased peak viscosity and noticeably smaller setback of wheat flour gels, which corresponded to lower gel hardness, serve as evidence of reduced amylose retrogradation. At 2%, MD outperformed ZG in terms of increasing water absorption, dough stability, and bread loaf volume. With the exception of the blend that included three times as much MD as ZG, all mixes, including the control, exhibited an increase in bread firmness as a function of time after storage. Overall, the panelists liked (score of 5 and above) the bread made with mixes that had either MD or ZG, or a combination of both.


Assuntos
Pão , Farinha , Pão/análise , Farinha/análise , Triticum , Polissacarídeos
8.
Molecules ; 27(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36364040

RESUMO

Acacia (AG) and cactus gums (CG) were mixed into wheat flour at the 3% and 6% levels. The flour blends were tested for their pasting, dough development, and extensibility behaviors. The blends were used to make cookies, which were then evaluated for their physical, textural, and sensory qualities. Both types of gum reduced the setback viscosities, water absorption, and farinograph quality numbers while increasing the water retention capacity, dough development time, and extensibility. The thickness and diameter of the cookies decreased in the presence of the cactus gum, while the acacia gum resulted in greater thickness and diameter. The addition of more gums increased the hardness of the cookies while decreasing their fracturability. All the cookie types were acceptable for all the sensory attributes studied. When compared to the control, the panelists preferred the color of the cookies with a higher level of gum. Overall, the presence of gums in the formulation resulted in the development of cookies with improved technological and sensory attributes. Likewise, the cookies with higher levels of gum can deliver 6% more soluble fiber without compromising their overall acceptability.


Assuntos
Acacia , Fabaceae , Opuntia , Farinha , Triticum , Fibras na Dieta , Água
9.
Phys Chem Chem Phys ; 23(33): 18112-18124, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34397071

RESUMO

We report a combined experimental and theoretical study of pure and doped cobalt ferrite where 25% of Fe3+ ions were replaced by Al3+, Ga3+, and In3+ ions, respectively, i.e., CoFe1.5X0.5O4 (X = Al, Ga, and In). The ferrite compositions were successfully synthesized using the solid-state reaction method. The X-ray powder diffraction method established that all ferrite samples had a spinel unit cell structure with the Fd3[combining macron]m (No. 227) space group. The lattice constants of ferrites increased from 8.382 Å (for undoped CoFe2O4) to 8.520 Å (for In-doped cobalt ferrite) in direct relation to the dopant ion size. The magnetic properties were obtained at 4.3 K and 300 K. At 4.3 K, the In-doped CoFe2O4 showed the highest saturation magnetic moment of 4.68 µB f.u.-1, while Al-doped CoFe2O4 showed the smallest value of 2.72 µB f.u.-1. The Fe3+ distribution among the spinel tetrahedral and octahedral sites was determined from the Mössbauer spectra. From ultraviolet-visible diffuse reflectance spectroscopy the direct optical bandgaps were determined, which have values between 1.20 eV and 1.28 eV for these ferrites. The ferrite compositions were also studied theoretically using plane-wave density functional theory using the CASTEP code where it was revealed that arrangements of the non-magnetic cations at the tetrahedral and octahedral sites strongly influence the electronic structure, the bandgap value, and the net magnetic moment per formula unit. Light Al3+ ions at the octahedral site give a low value of the net magnetic moment while the heavier Ga3+ and In3+ ions at the tetrahedral sites of the spinel give an enhanced magnetic moment. The magnetic moment values obtained from theoretical calculations match very well with the experimental values. Moreover, the theoretical calculations reveal that there exists a strong p-d hybridization among the oxygen and magnetic ions, which is affected by the non-magnetic dopant ions. The change in hybridization with the non-magnetic ion doping is responsible for the altered magnetic moments of the doped ferrites. Thus, our study provides a comprehensive investigation covering the synthesis and characterization of ferrites along with a good understanding of the phenomenon of how non-magnetic ion doping into spinel ferrites provides a method to tune the electronic and magnetic properties of the spinel ferrite.

10.
Nanotechnology ; 31(39): 395604, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32521529

RESUMO

The need for 2D vertical graphene nanosheets (VGNs) is driven by its great potential in diverse energy, electronics, and sensor applications, wherein many cases a low-temperature synthesis is preferred due to requirements of the manufacturing process. Unfortunately, most of today's known methods, including plasma, require either relatively high temperatures or high plasma powers. Herein, we report on a controllable synthesis of VGNs at a pushed down low-temperature boundary for synthesis, the low temperatures (450 °C) and low plasma powers (30 W) using capacitively coupled plasma (CCP) driven by radio-frequency power at 13.56 MHz. The strategies implemented also include unrevealing the role of Nickel (Ni) catalyst thin film on the substrates (Si/Al). It was found that the Ni catalyst on Si/Al initiates the nucleation/growth of VGNs at 450 °C in comparison to the substrates without Ni catalyst. With increasing temperature, the graphene nanosheets become bigger in size, well-structured and well separated. The role of Ni catalysts is hence to boost the growth rate, density, and quality of the growing VGNs. Furthermore, this CCP method can be used to synthesize VGNs at the lowest temperatures possible so far on a variety of substrates and provide new opportunities in the practical application of VGNs.

11.
Lipids Health Dis ; 18(1): 148, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272450

RESUMO

BACKGROUND: The present research project was designed to evaluate the cholesterol lowering potential of different date varieties including one exotic (Ajwa) and three Pakistani varieties (Aseel, Khudravi, Hallawi). METHODS: The albino rats were divided into six groups on the basis of different diets which includes, control having basal diet, high cholesterol high sucrose diet, high cholesterol high sucrose diet plus Khudravi dates, high cholesterol high sucrose diet plus Hallawi dates, high cholesterol high sucrose diet plus Aseel dates, high cholesterol high sucrose diet plus Ajwa dates to evaluate maximum cholesterol lowering potential of each date variety. RESULTS: The results showed that Hallawi and Ajwa have lower crude fiber content as 2.02 ± 0.03% and 2.43 ± 0.04% however, lowest crude fat content (0.26 ± 0.01%) was also observed in ajwa. Mineral profile depicted that sodium (9.50-18.00 mg/100 g) was found to be in lesser amount among all varieties whereas, higher amount of potassium (465.00 to 887.20 mg/100 g) depicted that it is suitable for people having hypertension. Higher amount of reducing sugar was also observed in ajwa (79.45 ± 1.22%) followed by Hallawi (77.68 ± 1.42%). Total phenolic contents were found higher in Aseel (291.36 mg/100 g) whereas, minimum was observed in Khudravi (232.64 mg/100 g). Furthermore, date varieties were also examined rat modeling to evaluate their maximum cholesterol lowering efficiency. Ajwa and Hallawi were observed to suppress the cholesterol efficiently as 110 mg/dL and 103 mg/dL respectively. On the basis of chemical profiling and other parameters, two date varieties Ajwa and Hallawi showed almost similar results and found to have maximum serum cholesterol, LDL and triglyceride reduction potential with good kidney and liver functions. Functional date bar was also developed by using Hallawi variety andsubjected to sensory evaluation. CONCLUSION: In nutshell, Hallawi date variety was considered as better cholesterol lowering potential among other indigenous varieties and very close to Ajwa variety. So that Hallawi can be used to suppress the deadly effects of obesity and allied discrepancies particularly hypercholesterolemia.


Assuntos
Alimento Funcional , Hipercolesterolemia/prevenção & controle , Phoeniceae/química , Animais , Antioxidantes/análise , Colesterol/sangue , Modelos Animais de Doenças , Alimento Funcional/análise , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/etiologia , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Minerais/análise , Valor Nutritivo , Paquistão , Fenóis/análise , Ratos Sprague-Dawley , Paladar , Triglicerídeos/sangue
12.
J Food Sci Technol ; 55(8): 3163-3173, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30065427

RESUMO

Antioxidant activities of different nut oils ranged from 11.43 (peanut) to 65.58% (pistachio) in cold pressed oils whereas in case of soxhlet extracted oils they were in the range of 11.32 (hazelnut) to 51.28% (pistachio). ß-Carotene contents of oils obtained by cold pressing and soxhlet extraction changed between 7.53 (almond) and 13.58 µg/100 g (pistachio). The highest total phenol contents (2.36 mg gallic acid equivalent/100 g) were observed in pistachio oils obtained by cold press. The oleic acid contents of cold pressed and soxhlet extracted oils were between 19.88 (walnut) and 69.43% (pecan) to 19.07 (walnut) and 68.53% (pecan), respectively. The linoleic acid contents of nut oils from cold press system vary between 12.78 (hazelnut) and 63.56% (walnut), whereas in case of soxhlet extraction, it changed between 11.78 (hazelnut) and 62.41% (walnut). The α-tocopherol contents of cold pressed nut oils changed between 0.07 (walnut) and 257.42 mg/kg (hazelnut) α-tocopherol contents of nut oils extracted by soxhlet extraction changed between 0.03 (pistachio) and 209.73 mg/kg (hazelnut). The catechin contents of cold pressed nut oils were between 0.56 (cashew) and 3.76 µg/100 g (pistachio), whereas that of soxhlet extracted oil varied between 0.64 (cashew) and 3.82 µg/100 g (cashew).

13.
Lipids Health Dis ; 16(1): 27, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28143531

RESUMO

BACKGROUND: Chicken meat contains higher percentage of polyunsaturated fatty acids that are susceptible to oxidative deterioration ultimately leading towards lower consumer acceptability for chicken meat products. Accordingly, meat processing industries are looking for combinations of natural antioxidants to enhance the oxidative stability and consumer acceptability of meat based products. The present study aimed to investigate the influence of directly added quercetin dihydrate in combination with α-tocopherol on oxidative stability, color characteristics, total carbonyls and flavor volatile compounds in chicken meat patties. METHODS: Considering the preliminary studies, 3 levels of quercetin dihdrate @ 25, 50 and 100 mg/kg meat in combination with α-tocopherol at the rate 100 and 200 mg/kg meat were added to develop chicken meat patties and were stored at refrigeration temperature for 7 days. The oxidative stability of the antioxidant treated patties was determined by measuring malonaldehydes using TBARS and total carbonyls assay. The color (Lightness, redness and yellowness) of the patties was determined by using Konica Minolta Color Meter. Moreover, the volatile compounds were measured through gas chromatography at various storage intervals. RESULTS: The results elucidated that quercetin dehydrate inclusion at the rate of 50 mg/kg meat as well as particularly 100 mg/kg meat decreased the oxidation by reducing generation of malonaldehydes and total carbonyls in treated patties. Highest value for TBARS at initiation of storage was reported in (T0) as 1.93 ± 0.02 whereas lowest were reported in T6 and T5 as 0.37 ± 0.01 and 0.38 ± 0.03 that were increased to 3.47 ± 0.14, 0.90 ± 0.05 and 0.94 ± 0.34 at the completion of storage. Moreover, the lowest carbonyls also reported in T6 and the values at various storage intervals (1st, 3rd and 7th) were as 0.59 ± 0.025, 0.77 ± 0.015 and 1.02 ± 0.031, respectively. The antioxidants inclusion also inhibited volatile flavoring compounds particularly aldehydes like hexanal and pentanal in a dose dependent manner (p ≤ 0.05). Lowest hexanal values reported in T6 as 2488 ± 103 followed by T4 (3701 ± 111) at the start of the trial whereas highest in T0 (control) as 54,768 ± 431 that were increased to 9569 ± 607, 112,550 ± 897 and 359,826 ± 1285, correspondingly. The hexanal, as a critical indicator for the determination of volatiles in meat based products, was decreased with the addition of antioxidants and its highest values were reported in control group. CONCLUSIONS: Quercetin dihydrate addition along with alpha tocopherol is a pragmatic choice to improve oxidative storability and volatile flavor compounds in cooked meat patties. The data obtained will help meat processor to better develop antioxidant enriched formulations to augment oxidative stability and quality of processed meat products.


Assuntos
Antioxidantes/química , Galinhas , Manipulação de Alimentos/métodos , Aves Domésticas , Aldeídos/análise , Aldeídos/química , Animais , Culinária , Proteínas de Drosophila , Armazenamento de Alimentos/métodos , Metabolismo dos Lipídeos , Lipídeos/química , Proteínas de Transporte da Membrana Mitocondrial , Oxirredução , Proteínas/química , Proteínas/metabolismo , Quercetina/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , alfa-Tocoferol/química
14.
Lipids Health Dis ; 16(1): 108, 2017 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-28595582

RESUMO

BACKGROUND: Current day consumers prefer natural antioxidants to synthetic antioxidants because they are more active. However, the activity generally depends on the specific condition and composition of food. The aim of this study was to investigate the effect of wheat germ oil and α-lipoic acid on the quality characteristics, antioxidant status, fatty acid profile, and sensory attributes of chicken nuggets. METHODS: Six types of diets were prepared for feeding the chickens to evaluate the quality of nuggets made from the leg meat of these experimental animals. These included control, diet enriched with wheat germ oil (WGO), which is a rich natural source of α-tocopherol (AT), diet with added AT or α-lipoic acid (ALA), diet with a combination of either ALA and WGO (ALA + WGO) or ALA and synthetic AT (ALA + AT). ALA has great synergism with synthetic as well as natural AT (WGO). RESULTS: The diet with WGO and ALA showed the best potential with respect to both antioxidant activity and total phenolic content. HPLC results revealed that the chicken nuggets made from WGO + ALA group showed maximum deposition of AT and ALA. The stability of the nuggets from control group was found to be significantly lower than that of nuggets from the WGO + ALA group. Total fatty acid content too was higher in the nuggets from this group. The poly unsaturated fatty acids (PUFA) were found to be higher in the nuggets from the groups fed with a combination of natural and synthetic antioxidants. CONCLUSION: It is concluded that the combination of natural and synthetic antioxidants in the animal feed exerts a synergistic effect in enhancing the stability and quality of chicken nuggets.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Carne/análise , Óleos de Plantas/administração & dosagem , Ácido Tióctico/administração & dosagem , Ração Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta , Ácidos Graxos/química , Ácidos Graxos/metabolismo
15.
Acta Pol Pharm ; 73(3): 787-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27476298

RESUMO

Irrational drug use practices are a burden to healthcare facilities. Poor prescribing practices affect the overall management and cost of treatment of non-communicable diseases that are the major cause of mortality and morbidity worldwide. In an effort to improve prescribing practices, this study was designed to assess prescribing, consultation and facility indicators in healthcare facilities of Punjab and Sindh provinces of Pakistan from December 2012 to December 2013. In this cross-sectional study, random and convenient sampling were used to collected data from both private and public healthcare facilities. Quantitative data were collected using structured questionnaire, observations and prescription analysis, whereas qualitative information on factors influencing prescribing practices was obtained by interviewing medical practitioners. A total of 13693 prescriptions were obtained from 500 patient-prescriber encounters. Results show that history taking, physical examination and diagnoses were adequate while generic prescribing was four-fold less than drugs prescribed by brands. Average number of drugs prescribed was 4.63 with more prescribing tendency in private facilities. 45.07% prescription costs were less than Rs. 150. Sulfonylureas, statins and ACE inhibitors were highly prescribed drugs for diabetes, hyperlipidemia and hypertension. Prescribing practices were dominantly influenced by severity of disease (73% Punjab; 81% Sindh), patient age (75% Punjab; 68% Sindh) and availability of drugs (62% Punjab; 56% Sindh) whereby 91% practitioners in Sindh and 52% in Punjab rely on medical representatives as the source of drug information. Moreover, the pharmacy and therapeutic committees in all facilities were non-functional along with non-availability of essential drug list in 87% health facilities. Thus, there are considerable opportunities to improve the rational use of medicines in Pakistan including low prices for generics, physician education, prescribing guidelines and formularies.


Assuntos
Tratamento Farmacológico/estatística & dados numéricos , Prescrição Inadequada/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Uso de Medicamentos , Medicamentos Genéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Assistência Farmacêutica , Adulto Jovem
16.
Acta Pol Pharm ; 73(4): 999-1007, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-29648726

RESUMO

Alendronate sodium, a bisphosphonate drug, it is used to treat osteoporosis and other bone diseases. The present study was designed to conduct comparative bioavailability analysis of oral formulations of aledronate sodium through an open-label, randomized, 2-sequence, 2-period crossover study. Healthy adult male Pakistani volunteers received a single 70 mg dose of the test or reference formulation of alendronate sodium followed by a 7 day washout period. Plasma drug concentrations were determined using a validated HPLC post column fluorescence derivatization method. AUC(01,) AUC(0-8,) C(max). and T(max) were determined by non-compartmental analysis and were found within the permitted range of 80% to 125% set by the US Food and Drug Administration (FDA). Results show that both in vitio and in vivo assays of all test brands were within the spec- ification of the US Pharmacopoeial limits and were statistically bioequivalent. No adverse events were reported in this study.


Assuntos
Alendronato/farmacocinética , Conservadores da Densidade Óssea/farmacocinética , Administração Oral , Adulto , Alendronato/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Composição de Medicamentos , Humanos , Masculino
17.
Pak J Pharm Sci ; 29(5): 1639-1648, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27731824

RESUMO

The microbial and chemical analysis of illicit drug samples from different areas of Pakistan i.e. Quetta, Karachi, Lahore and Islamabad was conducted in a cross-sectional study at National Institute of Health, Islamabad. The drug samples were confiscated by Anti Narcotics Force (ANF), Pakistan. Microbial analysis was done by estimating bioburden which revealed the presence of gram negative and positive bacteria's, fungus, Streptococcus, Staphylococcus species. Trypton soya agar was used for total aerobic count, MacConkey agar for gram-negative bacteria, Sabouraud dextrose agar for fungus and Vogel-Johnson agar for Streptococcus and Staphylococcus species. Colour tests were applied to identify the drug samples. Qualitative and quantitative analysis of suspected samples of Heroin, morphine, cocaine and acetic anhydride was made by employing different chromatographic techniques i.e. Thin-layer chromatography (TLC) and High-performance liquid chromatography (HPLC). The samples were found to be adulterated with paracetamol, diazepam and Dextromethorphen. Acetic anhydride was adulterated with hydrochloric acid (HCl). There is lack of information providing structured advice on responses to the consequences of illicit drug adulteration. Robust and rehearsed interventions and communication strategies would provide a basis for response for a wide variety of organisations. Research into the usefulness of media warnings about adulteration of illicit drugs is required.


Assuntos
Bactérias/isolamento & purificação , Contaminação de Medicamentos , Tráfico de Drogas , Fungos/isolamento & purificação , Drogas Ilícitas/análise , Técnicas Bacteriológicas , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Estudos Transversais , Humanos , Drogas Ilícitas/efeitos adversos , Paquistão , Medição de Risco
18.
Nutr J ; 14: 71, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26215288

RESUMO

Lignans are a group of phytonutrients which are widely distributed in the plant kingdom. Flaxseed is the richest source of providing lignan precursor such as secoisolariciresinol diglucoside (SDG). This article reviews the studies relevant to experimental models in animals and humans demonstrating the possible nutraceutical actions of SDG to prevent and alleviate lifestyle-related diseases. A local and international web-based literature review for this project was carried out to provide information relating to the study. The major key word "SDG" was selected to gather information using the electronic databases pertaining to the current state of flaxseed lignans composition, bioactive compounds, metabolism and to find out their role in terms of chemopreventive action. The extraction methods vary from simple to complex depending on separation, fractionation, identification and detection of the analytes. The majority of studies demonstrate that SDG interferes with the development of different types of diseases like cardiovascular, diabetic, lupus nephritis, bone, kidney, menopause, reproduction, mental stress, immunity, atherosclerosis, hemopoietic, liver necrosis and urinary disorders due to its various biological properties including anti-inflammatory, antioxidant, antimutagenic, antimicrobial, antiobesity, antihypolipidemic and neuroprotective effects. Moreover, SDG has a defending mediator against various cancers by modulating multiple cell signaling pathways. As discussed in this review, SDG has shown therapeutic potential against a number of human diseases and can be recommended for discerning consumers.


Assuntos
Butileno Glicóis/farmacologia , Linho/química , Glucosídeos/farmacologia , Lignanas/farmacologia , Animais , Antioxidantes/farmacologia , Quimioprevenção , Modelos Animais de Doenças , Humanos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
19.
Lipids Health Dis ; 14: 126, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26453429

RESUMO

BACKGROUND: The full-fat flaxseed meal has obtained relatively new flourished concept as staple chicken feedstuff for the production of designer eggs. However, unprocessed flaxseed also encloses well documented anti-nutritional factors which are associated with growth depression of laying hens. The present research work was carried out to evaluate the impact of full-fat extruded flaxseed meal supplemented diets on productivity performance of hens and production of modified ω-3 fatty acids-enriched eggs. METHODS: The full-fat flaxseed meal was extruded at barrel exit temperature (140 °C), screw speed (160 rpm) and feed rate (25 kg/h) for reduction of anti-nutritional compounds. One hundred and sixty, Babcock hens (age 24 weeks old) were selected at random from a large flock and ten hens were placed in each of 16 wire-mesh pens. The experimental diets prepared by supplementation of extruded flaxseed at 10%, 20% and 30% level were fed to hens along with control. RESULTS: The extruded flaxseed contained 86% and 76% less hydrocyanic compounds and tannin, respectively than the initial material. The hens fed with control diet consumed more feed, possessed heavy body weight and showed higher egg production as compared to hens fed on extruded flaxseed supplemented diets. The loss in body weight and egg production was recorded less for hens fed on 10% extruded flaxseed supplemented diets as compared to those fed on 30% extruded flaxseed supplemented diets. None of the experimental diets resulted in significant increase or decrease the total lipids and cholesterol content in egg yolk of hens. The extruded flaxseed supplemented diets resulted in a significant improvement of α-linolenic and docosahexaenoic acid in egg yolk with a concomitant reduction in arachidonic acid. The sensory scores were assigned higher to control eggs. Increasing level of extruded flaxseed in experimental diets decreased the scores for all sensory attributes of eggs. CONCLUSION: The present study suggested that extruded flaxseed meal up to 20% can be supplemented in the diets of hens for maximum deposition of α-linolenic acid and docosahexaenoic acid in egg yolk with acceptable detrimental effects on egg traits.


Assuntos
Ração Animal , Galinhas/metabolismo , Ovos , Ácidos Graxos Ômega-3/administração & dosagem , Animais , Suplementos Nutricionais , Ácidos Graxos Ômega-3/metabolismo , Feminino , Linho/química , Sementes/química
20.
Lipids Health Dis ; 14: 92, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26286266

RESUMO

BACKGROUND: The full-fat flaxseed (Linum usitatissimum L.) meal has obtained relatively new flourished concept as food or feedstuff for the development of healthier products. It provides favorable balance of polyunsaturated, monounsaturated and saturated fatty acids. However, flaxseed meal may be susceptible to oxidation by exposure to various storage conditions which is extremely undesirable and produces toxic compounds to human health. Another consideration in the application of flaxseed meal relates to the presence of anti-nutritional compounds that need to be minimized using appropriate processing method. The present research work was conducted to evaluate the impact of extrusion processing conditions and storage of full-fat flaxseed meal on functional characteristics such as α-linolenic acid content, lipid peroxidation and sensory attributes. METHODS: The raw flaxseed meal was analyzed for cyanogenic glycosides, tannin and mucilage anti-nutritional compounds. Fatty acids composition was quantified by gas chromatography. The meal was extruded at barrel exit temperature (100-140 °C), screw speed (50-150 rpm), feed rate (30-90 kg/h) and feed moisture (10-30 %) for reduction of anti-nutritional compounds. The raw and extruded meals were stored for a ninety-day period under room conditions (20-25 °C). Lipid peroxidation was analyzed by peroxide, free fatty acids, conjugated dienes, total volatiles and malondialdehyde assay. Color, aroma and overall acceptability attributes were evaluated by sensory multiple comparison tests. RESULTS: The raw flaxseed meal possessed significant amount of anti-nutritional compounds, lipid and α-linolenic acid contents. The extrusion processing at high barrel exit temperature (140 °C) significantly reduced the cyanogenic compounds (84 %), tannin (73 %) and mucilage (27 %) in the flaxseed meal. The α-linolenic acid content and lipid peroxidation did not significantly change after extrusion processing or during storage at the end of 60 days. Fluctuations in sensory attributes occurred during storage, but at the end of 90 days, only the extruded samples presented negative effect and showed lowest consumer acceptability. CONCLUSIONS: The present study suggested that extrusion of flaxseed meal at optimum conditions and stored for 60 days did not change the stability of full-fat flaxseed meal and can be used as supplement or ingredient for the production of various healthier products.


Assuntos
Suplementos Nutricionais/análise , Ácidos Graxos não Esterificados/análise , Linho/química , Manipulação de Alimentos/instrumentação , Ácido alfa-Linolênico/análise , Glicosídeos/isolamento & purificação , Humanos , Peroxidação de Lipídeos , Malondialdeído/análise , Mucilagem Vegetal/isolamento & purificação , Pressão , Taninos/isolamento & purificação , Temperatura
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