RESUMO
In this research, yarrow phenolic-rich extract was produced using pulsed electric field (PEF)-ultrasound assisted technology. The highest extraction efficiency (5.99 %) was obtained at 6.25 kV/cm of PEF and the sonication time of 60 min. As the PEF intensity and sonication time rose, the total phenolic content (TPC) and ferric-reducing power (RP) of the extracts increased. The PEF intensity of 2.70 kV/cm and sonication time of 45.83 min were the optimum extraction conditions resulting in the highest extraction efficiency, TPC, and RP. Then, this optimum extract was loaded into nanoliposomes. At higher extract levels, the encapsulation efficiency lowered, while the particle size, polydispersity index (PDI), and zeta potential of the nanoliposomal samples elevated. The results of Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) confirmed the successful encapsulation of yarrow extract into nanoliposomal carriers; the sample containing the extract had the highest enthalpy (3600 J/g) and nanoliposomes loaded with yarrow antioxidant extract (0.11 mL/mg) was the optimum sample. Finally, the sesame oil containing 500 ppm free and nanoliposome extract, as well as the sample with 200 ppm BHT were evaluated for oxidative stability. The highest oxidation stability (14.21 h) belonged to the oil containing nanoliposomal yarrow phenolic extract.
Assuntos
Lipossomos , Oxirredução , Fenóis , Óleo de Gergelim , Lipossomos/química , Fenóis/química , Fenóis/isolamento & purificação , Óleo de Gergelim/química , Eletricidade , Ondas Ultrassônicas , Sonicação/métodos , Fracionamento Químico/métodos , Tamanho da PartículaRESUMO
Application of novel technologies such as microwave and pulsed electric fields (PEF) might increase the speed and efficiency of oil extraction. In the present research, PEF (3.25 kV/cm electric field intensity and 30 pulse number) and microwave (540 W for 180 s) pretreatments were used to study the process of oil extraction from black cumin (Nigella sativa) seeds. After applying the selected pretreatments, the oil of seeds was extracted with the use of a screw press and the extraction efficiency, refractive index, oil density, color index, oxidative stability, and chemical components of oil and protein of meal were evaluated. The achieved results expressed that PEF and microwave pretreatments increased the oil extraction efficiency and its oxidative stability. Different pretreatments didn't have any significant influence on the refractive index of black cumin seed oil (p>.05). When microwave and PEF were used, the oil density showed an enhancement as the following: 1.51% and 0.96%, respectively in comparison with the samples with no pretreatments. Evaluation of the extracted oils, using GC/MS analysis indicated that thymoquinone was the dominant phenolic component in the black cumin oil. Finally, the SEM analysis revealed that microwave and PEF can be useful in the extraction of oil from black cumin seeds since these treatments damaged cell walls and facilitated the oil extraction process.
RESUMO
In the present study, the impacts of germination time on the enzymes activity attributed in malting and some polysaccharides contents of the malt prepared from the Joseph barley variety have been screened using a completely random design with three levels of germination time(3, 5 and 7days). The archived outcomes revealed that the highest quantity of starch has been observed in the malt resulted from 3days germination, and an enhancement in the germination period from 3 to 7days decreased the quantity of available starch. An enhancement in the germination period presented a reduction in the beta-glucan quantity in the malting seeds. The malt produced 7days after germination had the highest enzymatic activity(253U.kg-1). The comparison of data average using Duncan test showed that the minimum and maximum value of α-Amylase enzyme activity and diastatic power were recorded in the malts produced 3 and 7days after germination, respectively. Increasing in the germination time led to a reduction in malting efficiency, however the efficiency of the hot water extraction showed enhancement. The outcomes of the correlation between the studied parameters showed that the beta-glucan and starch quantities are negatively affected by the activities of beta-Glucanase and α-Amylase.
Assuntos
Germinação/fisiologia , Glicosídeo Hidrolases/química , Amido/química , beta-Glucanas/química , Fermentação , Hordeum/química , Hordeum/enzimologia , Temperatura Alta , Extração Líquido-Líquido , Estações do Ano , Amido/isolamento & purificação , Fatores de Tempo , Água/química , alfa-Amilases/química , beta-Glucanas/isolamento & purificaçãoRESUMO
The inputs of this network were the concentration of pectinase and time of incubation, and the outputs were extracted lycopene and the activity of radical scavenging activity. Two different networks were designed for the process under the sonication and without it. For optimal network, networks' transfer functions and different learning algorithms were evaluated and the validity of each one was determined. Consequently, the feedforward neural network with function of logarithmic transfer, Levenberg Marquardt algorithm and 4 neurons in the hidden layer with the correlation coefficient of 0.96 and 0.99 were respectively observed for the treatments under sonication and without it, furthermore, root mean squared error and standard error values were obtained 0.46 and 0.22 respectively for the treatments under sonication and 0.77 and 0.38 without it as respectively optimal networks. The selected networks could determine the chosen responses, individually and in combined effect of both inputs as well (R(2) > 0.98).