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Water and food utilization efficiencies in sheep and their relationship with some production traits Полный текст
2021
Barros de Freitas, Ana Carolina | Bartholazzi Junior, Aylton | Quirino, Celia Raquel | Costa, Ricardo Lopes Dias da
The objective of this study was evaluate the efficiency in water and food use in sheep production, using two new traits (residual water intake - RWI; residual feed and residual water intake - RFRWI). For this purpose, we evaluated the relationships between the traits total water intake, RWI and RFRWI with water measures, productive performance and carcass traits (ultrasound). We used 32 lambs with age of 3 months: 16 Santa Ines breed (8 males and 8 females) and 16 crossbred 7/8 Dorper x Santa Ines (8 males and 8 females). They were fed at an automated feed and water station (Intergado®), where the food and water intake by each animal was measured automatically. Residual water intake (RWI), residual feed intake (RFI) and residual body weight gain (RWG) were calculated using the MIXED procedure in SAS®. Correlation coefficients between total water intake (TWI), RWI and all traits (water measures, performance and carcass traits) were calculated using the CORR procedure (P ≤ 0.05). Total water intake showed mean 3.15 L/day during the study and the RWI ranged from 0.66 L to -0.89 L, which represents a difference of 1.55 L between the most and least efficient animal. There was positive correlation between less efficient animals in water consumption (positive RWI) and water intake (r = 0.31); total water intake in relation to dry matter intake (r = 0.36); total water intake in relation to mid-trial metabolic body weight (r = 0.26); residual feed and residual water intake (r = 0.99) and gain/feed ratio (r = 0.44). There was negative correlation between less efficient animal and dry matter intake in relation to body weight (r= -0.33) and feed conversion ratio (r= -0.44). The evaluation of the new variables, RWI and RFRWI, proved effective in identifying the most efficient animals in water use. Moreover, these findings open the possibility of considering the traits RWI and RFRWI in sheep selection, because performance and carcass traits are not adversely affected by selecting for these new traits.
Показать больше [+] Меньше [-]Ultrasonic degradation kinetics and rheological profiles of a food polysaccharide (konjac glucomannan) in water Полный текст
2017
Li, Jing | Li, Bin | Geng, Ping | Song, Ang-Xin | Wu, Jian-Yong
This study was carried out to evaluate the effects of power ultrasound (US) on the molecular weight and rheological properties of a food polysaccharide, konjac glucomannan (KGM). Upon the exposure of KGM solution (1% w/v in water) to US at a relatively high power intensity (50 W/cm2), the apparent viscosity decreased rapidly from about 50 Pa s to a negligible level within 10–20 min. The intrinsic viscosity ([η]) of KGM solution decreased gradually during the US exposure with a time course closely fitted to the first-order polymer degradation kinetics (random chain scission). The US treatment also caused a significant reduction of particle size (Zavg) of KGM aggregates and changes in the rheological properties including the decrease of storage modulus (G′) and loss modulus (G″), and the increase in phase angle (tan δ = G″/G′). Nevertheless, no change in primary structure was detected by Fourier transformation infrared (FT-IR) analysis. The results suggested that high intensity US was an effective means for KGM degradation without significant structural destruction.
Показать больше [+] Меньше [-]Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste Полный текст
2016
Paini, Marco | Casazza, Alessandro A. | Aliakbarian, Bahar | Perego, Patrizia | Binello, Arianna | Cravotto, Giancarlo
The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.
Показать больше [+] Меньше [-]Determination of Cobalt in Food and Water Samples by Ultrasound-assisted Surfactant-enhanced Emulsification Microextraction and Graphite Furnace Atomic Absorption Spectrometry Полный текст
2014
Liang, Pei | Yu, Juan | Yang, Enjian | Mo, Yajuan
A novel method based on ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME) has been developed for the preconcentration of cobalt prior to its determination by graphite furnace atomic absorption spectrometry. In the UASEME technique, chloroform was used as the extraction solvent, sodium dodecyl sulfate was adopted as emulsifier, and ultrasound was applied to assist emulsification. There is no need of using organic dispersive solvent which is typically required in conventional dispersive liquid–liquid microextraction method. Several parameters that affect the extraction efficiency, such as the kind and volume of the extraction solvent, the type and concentration of the surfactant, pH of sample solution, concentration of the chelating agent, and extraction time and temperature were investigated and optimized. Under the optimal conditions, the linearity of calibration curve was in the range of 0.1–5 ng mL⁻¹with a correlation coefficient (R²) of 0.9992. An enrichment factor of 58 was achieved with a sample volume of 5.0 mL. The detection limit of this method for Co was 15.6 ng L⁻¹, and the relative standard deviation (RSD) was 4.3 % at 1.0 ng mL⁻¹concentration level of Co. The accuracy of the developed method was evaluated by analysis of the certified reference materials GBW07605 tea leaf and GBW10015 spinach. The method was successfully applied to determine trace cobalt in food and water samples with satisfactory results.
Показать больше [+] Меньше [-]Scallops as a new source of food protein: high‐intensity ultrasonication improved stability of oil‐in‐water emulsion stabilised by myofibrillar protein Полный текст
2022
Yu, Cuiping | Sun, Shuang | Li, Sihui | Yan, Huijia | Zou, Henan
In this study, the effect of high‐intensity ultrasound (HIUS) (200 and 400 W for 0, 5, 10 and 15 min respectively) on conformational changes, physicochemical, rheological and emulsifying properties of scallop (Patinopecten yessoensis) myofibrillar protein (SMP) was investigated. HIUS‐treated SMP had lower α‐helix content and higher β‐sheet content compared with the native SMP. HIUS treatment induced the unfolding of SMP and increased the surface hydrophobicity. The particle size of SMP decreased and the absolute zeta‐potential increased after ultrasonication, which in turn increased the solubility of SMP. The conformational changes and the improvement of physicochemical properties of SMP increased the ability for SMP to lower the interfacial tension at the oil–water interface and increased the percentage of adsorbed protein. As a result, the emulsifying properties, rheological properties of SMP and storage stability of emulsions were also improved. In conclusion, HIUS treatment has future potential for improving the emulsifying properties of SMP.
Показать больше [+] Меньше [-]Ultrasound assisted dispersive solid phase microextraction of inorganic arsenic from food and water samples using CdS nanoflowers combined with ICP-OES determination Полный текст
2021
Ahmad, Hilal | Zhao, Lihua | Liu, Changkun | Cai, Chaojie | Ma, Fuqing
Direct determination of arsenic species in real samples is challenging due to their trace concentration and spectral interferences by coexisting ions. Herein, we proposed an ultrasound-assisted dispersive solid phase microextraction (DSPME) procedure for the analyses of the trace inorganic arsenic. The hydrothermally synthesized cadmium sulfide nanoparticles (CdS NPs) completely adsorbed both arsenic species within 20 s at the initial arsenic concentration of 100 µg L⁻¹. The detection limit (3 S/m) of the proposed method was found to be 0.5 ± 0.2 and 0.8 ± 0.2 ng L⁻¹ for As(III) and As(V), respectively. The accuracy of the method against the systematic and constant errors was confirmed by the analysis of the Standard Reference Material (SRM) (>95% recovery with <5% RSD). The Student’s t-test values were found to be less than the critical Student’s t value at a 95% confidence level. The method was successfully employed for the determination of arsenic in food samples.
Показать больше [+] Меньше [-]Use of hydrolytic enzymes as green and effective extraction agents for ultrasound assisted-enzyme based hydrolytic water phase microextraction of arsenic in food samples Полный текст
2018
Yilmaz, Erkan
In order to contribute to the development and improvement of green sample preparation techniques, a new special approach combining the principles and advantages of microextraction techniques, hydrolytic enzymes and ultrasonic radiation power is presented. This new approach is called as ultrasound assisted-enzyme based hydrolytic water phase microextraction method (UA-EH-WPME). In this study, We developed and used a solvent-free UA-EH-WPME method as innovative, green and simple sample preparation method for the extraction of arsenic (As) in rice and flour samples prior to Inductively Coupled Plasma–Mass Spectrometer (ICP-MS) determination. The UA-EH-WPME method based on the extraction of total As in 10.0 mg of food samples to 300 µL of pH 7.0 aqueous phase with the help of the 3.0 mg of α-amylase in as little as 5 min. In this method, α-amylase acts as a bond breaker agent to break down certain bonds of bio-molecules in food matrix, which lead to extraction of As from food matrix to aqueous phase. 1568A Rice Flour certified reference material was used to optimize the important analytical parameters, which were type of hydrolytic enzyme, pH, volume of aqueous phase, amount of enzyme, temperature of extraction medium and time of ultrasonic radiation, for the quantitative extraction of As from food matrix to aqueous phase. This innovative solvent-free method leads to emerge new ideas in the sample preparation field, by using the benefits of microextraction techniques, hydrolytic enzymes and ultrasonic radiation power, such as elimination of the toxic solvent usage, necessity of mg level of enzyme and food samples, very short and simple extraction process. The LOD, inter-day RSD and intra-day RSD values for the developed UA-EH-WPME/ICP-MS procedure were found as 27.3 µg kg⁻¹, 4.27% and 6.13%, respectively.
Показать больше [+] Меньше [-]Application of Ultrasonic Assisted-Dispersive Solid Phase Extraction Based on Ion-Imprinted Polymer Nanoparticles for Preconcentration and Trace Determination of Lead Ions in Food and Water Samples Полный текст
2017
Kakavandi, Masoud Ghanbari | Behbahani, Mohammad | Omidi, Fariborz | Hesam, Ghasem
In this paper, we describe ultrasonic assisted-dispersive solid phase extraction based on ion-imprinted polymer (UA-DSPE-IIP) nanoparticles for the selective extraction of lead ions. Ultrasound is a good and robust method to facilitate the extraction of the target ions in the sorption step and elution of the target ions in the desorption step. The ion-imprinted polymer nanoparticles used in the UA-DSPE-IIP were prepared by precipitation polymerization technique. The ion-imprinted polymer nanoparticles was synthesized using 2-vinylpyridine as a functional monomer, ethylene glycol dimethacrylate as the cross-linker, 2,2′- azobisisobutyronitrile as the initiator, 1,3,4-thiadiazole-2,5-dithiol as the ligand, methanol/dimethyl sulfoxide as the solvent, and lead as the template ion, through precipitation polymerization technique. The IIP nanoparticles were characterized by Fourier transformed infra-red spectroscopy (FTIR), thermogravimetric and differential thermal analysis (TGA/DTA), and scanning electron microscopy (SEM). Box-Behnken design (BBD) was used for optimization of sorption and desorption steps in UA-DSPE-IIP. In the sorption step: pH of solution, IIP amount (mg), sonication time (min) for sorption and in the desorption step: concentration of eluent (mol L⁻¹), volume of eluent (mL), and sonication time (s) for desorption was investigated and optimized by the Box-Behnken design. The optimum conditions for the method were pH of solution: 7.5, sonication time for sorption 7.5 min, IIP amount 24 mg, type and concentration of eluent HCl 1.4 mol L⁻¹, volume of eluent 2.1 mL, and sonication time for desorption 135 s. Under the optimized conditions, the limit of detection and relative standard deviation for the detection of lead ions by UA-DSPE-IIP was found to be 0.7 μg L⁻¹ and <4%, respectively.
Показать больше [+] Меньше [-]Ultrasonic assisted dispersive liquid-liquid microextraction method based on deep eutectic solvent for speciation, preconcentration and determination of selenium species (IV) and (VI) in water and food samples Полный текст
2017
Panhwar, Abdul Haleem | Tuzen, Mustafa | Kazi, Tasneem Gul
A novel ultrasound-assisted liquid phase microextraction (UALPME) based on environmental friendly extractants, deep eutectic solvent (DES) was first time presented for speciation of selenium. In present study, five DES solvents of different composition was prepared and used as efficient extractive medium for hydrophobic chelate of Se(IV) with 3,3′-Diaminobenzidine (DAB). The total inorganic Se species were determined after pre-reduction of Se(VI) to Se(IV), prior to applying developed method. The concentration of Se(VI) was calculated by the difference of Se(IV) values and total selenium contents. The concentration of Se in DES rich phase was measured with electrothermal atomic absorption spectrometer (ETAAS). The effects of different parameters on extraction efficiency of study analyte, including pH, ligand concentration, type and volume of DES, sonication time, volumes tetrahydrofuran and aqueous samples were examined. At the optimum conditions, limit of detection and quantification, preconcentration factor, and relative standard deviation (RSD %) were determined as 4.61ngL⁻¹, 15.4ngL⁻¹, 50% and 4.1%, respectively. The accuracy of the presented method was confirmed by analysis of certified reference material and standard addition method for different water and ice tea samples. The developed method was effectively applied to real water and food samples.
Показать больше [+] Меньше [-]A New Ultrasonic Thermostatic-Assisted Cloud Point Extraction/Spectrophotometric Method for the Preconcentration and Determination of Bisphenol A in Food, Milk, and Water Samples in Contact with Plastic Products Полный текст
2017
Yıldırım, Emre | Gürkan, Ramazan | Altunay, Nail
Bisphenol A (BPA) contamination in foods and beverages usually occurs as a result of migration from the packages that contain it. In this context, a simple, easy-to-use, and efficient method was developed for the spectrophotometric determination of BPA in food, milk, and water samples in contact with plastic products after preconcentration by ultrasonic-thermostatic-assisted cloud point extraction (UTA-CPE). The method is based on the charge transfer-sensitive complexation of BPA with 3-methylamino-7-dimethylaminophenothiazin-5-ium chloride (AzB) in the presence of cetyltrimethylammonium bromide (CTAB) at pH 8.5 and then extraction of the formed complex into the micellar phase of polyethylene glycol dodecyl ether (Brij 35). The effects of the analytical variables affecting complex formation and extraction efficiency were systematically studied and optimized. Under optimized conditions, a good linear relationship was obtained in the range of 1.2–160 μg L⁻¹ with a detection limit of 0.35 μg L⁻¹. After preconcentration of a sample of 20 mL, a sensitivity enhancement factor was found to be 180. The accuracy and reliability of the method were evaluated by recovery studies from the spiked quality control samples and intraday and interday precision studies. From the studies conducted, the extraction efficiency (E%) was in the range of 94–103% with a relative standard deviation lower than 5.2% (as RSD%, n = 5). The method was successfully applied to the preconcentration and determination of BPA from the selected sample matrices. Graphical Abstract Migration of bisphenol A into the foodstuffs
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