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1.
High-energy assisted extraction techniques, like ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), are widely applied over the last years for the recovery of bioactive compounds such as carotenoids, antioxidants and phenols from foods, animals and herbal natural sources. Especially for the case of xanthophylls, the main carotenoid group of crustaceans, they can be extracted in a rapid and quantitative way with the use of UAE and MAE.  相似文献   
2.
In this study, supercritical fluid extraction (SFE), ultrasonic-assisted extraction (UAE), and microwave-assisted extraction (MAE) were applied to explore the most suitable extraction method for fatty acids of Potentilla anseris L. from 12 different producing areas of the Qinghai-Tibetan Plateau. Meanwhile, the important experimental parameters that influence the extraction process were investigated and optimized via a Box-Behnken design (BBD) for response surface methodology (RSM). Under optimal extraction conditions, 16 fatty acids of Potentilla anserina L. were analyzed via high-performance liquid chromatography (HPLC) with fluorescence detection, using 2-(4-amino)-phenyl-1-hydrogen-phenanthrene [9,10-d] imidazole as the fluorescence reagent. The results showed that the amounts of total fatty acids in sample 6 by applying SFE, UAE, and MAE were, respectively, 16.58 ± 0.14 mg/g, 18.11 ± 0.13 mg/g, and 15.09 ± 0.11 mg/g. As an environmental protection technology, SFE removed higher amounts of fatty acids than did MAE, but lower amounts of fatty acids than did UAE. In addition, the contents of the 16 fatty acids of Potentilla anserina L. from the 12 different producing areas Qinghai-Tibetan Plateau were significantly different. The differences were closely related to local altitudes and to climatic factors that corresponded to different altitudes (e.g., annual mean temperature, annual mean precipitation, annual evaporation, annual sunshine duration, annual solar radiation.). The temperature indices, photosynthetic radiation, ultraviolet radiation, soil factors, and other factors were different due to the different altitudes in the growing areas of Potentilla anserina L., which resulted in different nutrient contents.  相似文献   
3.
Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS+ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g−1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS+ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with “ε” values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the “ε” of the solvents for future metabolomic studies.  相似文献   
4.
In this work, extraction of flavonoids from peanut shells has been studied in the presence of ultrasound and the results are compared with Soxhlet and heat reflux extraction for establishing the process intensification benefits. The process optimization for understanding the effects of operating parameters, such as ethanol concentration, particle size, solvent to solid ratio, extraction temperature, ultrasonic power and ultrasonic frequency, on the extraction of flavonoids has been investigated in details. The highest extraction yield (9.263 mg/g) of flavonoids was achieved in 80 min at optimum operating parameters of particle size of 0.285 mm, solvent to solid ratio of 40 ml/g, extraction temperature of 55 °C, ultrasonic power of 120 W and ultrasonic frequency of 45 kHz with 70% ethanol as the solvent. Two kinetic models (i.e. phenomenological model and Peleg’s model) have been introduced to describe the extraction kinetic of flavonoids by fitting experimental data and predict kinetic parameters. Good performance with slight loss of goodness of fit of two models was found by comparing their coefficient of determination (R2), root mean square error (RMSE) and/or mean percentage error (MPE) values. This work would provide the reduction of degradation and the economic evaluation for the extraction processes of flavonoids from peanut shells, as well as give a better explanation for the mechanism of ultrasound.  相似文献   
5.
BackgroundThis study, for the first time, reports a simultaneous determination of flavonoids; rutin (RT), quercetin (QT), luteolin (LT), and kaempferol (KF) in different origins of fenugreek seeds samples (N = 45) using a green UHPLC-DAD analysisMethodologyUltrasound-assisted extraction (UAE) was employed to extract fenugreek flavonoids using different polarity solvents of n-hexane (n-hex), dichloromethane (DCM), and methanol (MeOH)ResultsThe extract yield on an individual basis was observed in the range of 1.03–17.29 mg, with the highest yield (mg/sample) for the Egyptian sample (17.29 mg). The highest total extract yield (mg/origin) was observed for the Iranian sample (82.28 ± 5.38). The solvent with the highest extract yield (mg) was n-hex 169.35 ± 13.47, followed by MeOH 114.39 ± 12.27. The validated green UHPLC-DAD method resulted in a short runtime (9 min) with an accuracy of 97.86(±12.32)-101.37(±5.91), r2-values = 0.993–0.999, LOD = 2.09–4.48 ppm, and LOQ = 6.33–13.57 ppm for flavonoids analysis within the linearity range of 1–500 ppm. The general yield for flavonoids exhibited a descending order (ppm): RT (2924.55 ± 143.84) > QT (457.05 ± 34.07) > LT (82.37 ± 3.27) > KF (4.54 ± 0.00). The yield (ppm) for the flavonoids was more in MeOH solvent (3424.81 ± 235.44) constructing a descending order of MeOH > n-hex > DCM. For an individual flavonoid yield; MeOH was seen with an order of RT > QT > LT, n-hex (LT > QT), and DCM (RT > LT > QT). The statistical analysis of PCA (principle component analysis) revealed a widespread distribution of flavonoids in fenugreek seeds with a variance of 35.93% (PC1). Moreover, flavonoids extraction was prone to the nature and specificity of the solvent used (PC2: 33.34%) rather than the amount of the extract yield (P = 0.00). The K-mean cluster analysis showed the origins with higher flavonoids yield in appropriate solvent as I3M (Indian accession # 3 MeOH extract) with more QT amount, IR2M (Iranian accession # 2 MeOH extract) with more LT amount along with I2M (Indian accession # 2 MeOH extract) and Q2M (Qassim Saudi Arabia accession # 2 MeOH extract) containing high amount of RT. The outcomes are supported by KMO (Kaiser-Meyer-Olkin) and Bartlett’s test value of 0.56 with X2-value of 191.87 (P = 0.00)ConclusionThe samples were effectively evaluated and standardized in terms of flavonoid amount suggesting a significant variation in fenugreek quality.  相似文献   
6.
The residue after sieving (“dust”) from the willow gentian underground parts is an unexploited herbal tea by-product, although it contains valuable bioactive compounds. Cyclodextrins as efficient green co-solvents, cage molecules, and multifunctional excipients could improve the extraction and contribute to the added value of the resulting extracts. The objective of this study was to determine the optimal conditions for the extraction of gentiopicroside, isogentisin, and total phenolics (TPC) from willow gentian “dust” using ultrasound-assisted water extraction coupled with hydroxypropyl-β-cyclodextrin (HPβCD). The influence of extraction temperature (X1: 20–80 °C), time (X2: 20–50 min), and HPβCD concentration (X3: 2–4% w/v) was analyzed employing the response surface methodology (RSM). The optimal extraction conditions for simultaneously maximizing the extraction yield of all monitored responses were X1: 74.89 °C, X2: 32.57 min, and X3: 3.01% w/v. The experimentally obtained response values under these conditions (46.96 mg/g DW for gentiopicroside, 0.51 mg/g DW for isogentisin, and 12.99 mg GAE/g DW for TPC) were in close agreement with those predicted, thus confirming the suitability and good predictive accuracy of the developed RSM models. Overall, the developed extraction system could be an applicable alternative strategy to improve the extraction of bioactive compounds from the underutilized “dust” of willow gentian underground parts.  相似文献   
7.
Currently there is a drive towards the minimisation and reclamation of valuable materials from the waste products of the food and beverage industry. This can be achieved through the extraction of residual nutraceuticals from such materials. Tomato pomace contains carotenoids and other chemicals which can be extracted directly into edible oils to improve the health-giving properties of such oils. We report here a novel green solvent, fatty acid ethyl esters (FAEE), which is significantly more effective than sunflower oil and hexane for the extraction of lycopene and beta-carotene from tomato skin waste. FAEE are a non-toxic renewable resource that is environmentally friendly and to our knowledge has never been used as a vegetal extraction fluid. The efficiency of FAEE extraction was significantly improved relative to both sunflower oil and hexane under ultrasound-assisted extraction (UAE) conditions. In addition, FAEE have the additional and significant advantage that once enriched with the extracted nutraceuticals can be used directly as a food additive.  相似文献   
8.
The aim of this study was to verify various extraction methods: shaking water bath extraction (SWA), ultrasound-assisted extraction (UAE) and microwave assisted extraction (MAE), and their parameters to optimize the extraction yield as well as maximize the concentration of polyphenols in Plectranthus barbatus extracts. Extracts were obtained from dried roots of P. barbatus in various degrees of fragmentation and analyzed for content of polyphenols, antioxidant capacity and flavonoids. Additionally, phenolic compounds in extracts were analyzed using the UHPLC–DAD–ESI–MS/MS method. The conducted research showed that roots of P. barbatus are rich in polyphenolic compounds. A total of 15 phenolic compounds, belonging to the group of phenolic acids and their derivatives, were identified. The extraction yield was similar for all extraction methods and averaged 31%. Irrespective of the extraction method, the yield was the lowest in the case of using 80% ethanol as the solvent. The extracts obtained from the finer fraction were characterized by a higher antioxidant capacity as well as a higher concentration of polyphenolic compounds including flavonoids. UAE seems to be the most effective method for extraction of polyphenols from P. barbatus roots. Regardless of the extraction method, ethanol was a better extractant than distilled water. All ethanolic extracts were characterized by a high antioxidant capacity. The 80% ethanol solution was considered the best solvent for the extraction of flavonoids, while the 40% and 60% ethanol solutions were sufficient for the effective extraction of polyphenolic compounds in general.  相似文献   
9.
Cereal brans are by‐products of the milling of cereal grains, which are mainly used as low value ingredients in animal feed. Wheat and oat bran is a rich source of bioactives and phytochemicals, especially phenolic compounds. Within this study, the application of ultrasound (US) technology to assist the extraction of phenolics from oat and wheat bran was investigated (20–45 kHz). Peleg’s mathematical model was used to study the kinetics of ultrasound-assisted extraction (UAE) and subsequent stirring of total phenolic compounds (TPC). The surface morphology of cereal brans after extraction was studied using SEM analysis. The excellent agreement was determined between the values of TPC calculated from Peleg’s mathematical model and actual experimental results. The constant that represents a time required for the initial phenolic concentration to be extracted to one-half of its initial value has been introduced (K1/2). It was shown that the TPC extraction kinetics was dependent only on K1/2 enabling fast kinetics fitting and comparison between extraction rates. Moreover, different values of K1/2 constant could indicate the differences in brans composition and consequently different influence of US pretreatment on these samples.  相似文献   
10.
Textile materials with engineered nanoparticles (ENPs) have excellent properties as they are antibacterial, antimicrobial, water resistant and protective. The textile industry has recognized the importance and the advantages of ENPs, so they comprise one of the fastest developing branches of processing.The most important sources of ENPs released to the environment from textiles are textile-industry wastewaters and waters from large hospital or hotel laundries. In addition, waste textile materials coated with ENPs present a threat to the environment, if such materials are not properly handled and disposed of after use.Currently, the toxicity and the potential harm of ENPs widely applied on textiles are not thoroughly investigated and/or eliminated. Consequently, there is an urgent need to define the most appropriate analytical methods for monitoring ENPs on textiles.This review presents the most important techniques for monitoring ENPs on textile materials and in textile-wastewater samples, from the perspective of protecting the environment and human health.  相似文献   
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