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Optimizing the Extraction of Procyanidins Oligomers through Decamer
The extraction of procyanidins from a food is influenced by food matrix, extraction solvent, sample particle size, sample to solvent ratio, as well as other factors. Many of these parameters can easily be controlled in a laboratory to improve or target the extraction of low or high molecular weight oligomers. As various oligomers have differing biological and functional qualities, preferred extraction of one group of oligomers may be a desired target. In the following study, we describe the influence of solvent polarity and composition, solvent-solute ratio and particle size on the extraction of procyanidin oligomers monomer through decamer. The solvents evaluated included dimethyl sulfoxide (DMSO), acetone and methanol
Extraction of Anthocyanins and Total Phenolic Compounds from Acai (Euterpe oleracea Mart.) Using an Experimental Design Methodology. Part 2: Ultrasound-Assisted Extraction
Two optimized methods for ultrasound-assisted extraction were evaluated for the extraction of two types of acai bioactive compounds: Total anthocyanins (TAs) and total phenolic compounds (TPCs). For the extraction optimization, a Box Behnken factorial design of different variables in the following intervals was used: Methanol-water (25%-75%) for solvent composition, temperatures between 10 and 70 degrees C, amplitude in the range between 30% and 70% of the maximum amplitude -200 W), extraction solvent pH (2-7), the ratio for sample-solvent (0.5 g:10 mL-0.5 g:20 mL), and cycle between 0.2 and 0.7 s. The extraction kinetics were studied using different periods between 5 and 30 min. TA and TPC were analyzed by UHPLC and the Folin-Ciocalteu method, respectively. Optimized conditions for TA were: 51% MeOH in water, 31 degrees C temperature, pH 6.38, cycle 0.7 s, 65% amplitude, and 0.5 g:10 mL of sample-solvent ratio. Optimized conditions for the TPC were: 49% MeOH in water, 41 degrees C temperature, pH 6.98, cycle 0.2 s, 30% amplitude, and 0.5 g:10 mL of sample-solvent ratio. Both methods presented a relative standard deviation below 5% in the precision study. The suitability of the methods was tested in real samples. It was confirmed that these methods are feasible for the extraction of the studied bioactive compounds from different acai matrices
Supercritical multicomponent solvent coal extraction
The yield of organic extract from the supercritical extraction of coal with larger diameter organic solvents such as toluene is increased by use of a minor amount of from 0.1 to 10% by weight of a second solvent such as methanol having a molecular diameter significantly smaller than the average pore diameter of the coal
Optimizing a sustainable ultrasound assisted extraction method for the recovery of polyphenols from lemon by-products:comparison with hot water and organic solvent extractions
Response surface methodology (RSM) based on a three-factor and three-level Box–Behnken design was employed for optimizing the aqueous ultrasound-assisted extraction (AUAE) conditions, including extraction time (35–45 min), extraction temperature (45–55 °C) and ultrasonic power (150–250 W), for the recovery of total phenolic content (TPC) and rutin from lemon by-products. The independent variables and their values were selected on the basis of preliminary experiments, where the effects of five extraction parameters (particle size, extraction time and temperature, ultrasonic power and sample-to-solvent ratio) on TPC and rutin extraction yields were investigated. The yields of TPC and rutin were studied using a second-order polynomial equation. The optimum AUAE conditions for TPC were extraction time of 45 min, extraction temperature of 50 °C and ultrasonic power of 250 W with a predicted value of 18.10 ± 0.24 mg GAE/g dw, while the optimum AUAE conditions for rutin were extraction time of 35 min, extraction temperature of 48 °C and ultrasonic power of 150W with a predicted value of 3.20 ± 0.12 mg/g dw. The extracts obtained at the optimum AUAE conditions were compared with those obtained by a hot water and an organic solvent conventional extraction in terms of TPC, total flavonoid content (TF) and antioxidant capacity. The extracts obtained by AUAE had the same TPC, TF and ferric reducing antioxidant power as those achieved by organic solvent conventional extraction. However, hot water extraction led to extracts with the highest flavonoid content and antioxidant capacity. Scanning electron microscopy analysis showed that all the extraction methods led to cell damage to varying extents
Optimization of a new extraction technique for analysis of verbenone and cis-verbenol in pine seeds
Results from a systematic study of the factors affecting extraction of cis-verbenol and verbenone
from pine seeds are presented. Five extraction conditions were investigated: extraction solvent,
method of extraction, extraction temperature, volume of solvent, and the ratio of the mass of
sample to the amount of extraction solvent
Evaluation of a two-phase extraction system of carbohydrates and proteins from chlorella vulgaris utex 1803
Microalgae are a valuable source of high-value products and biofuels, however the high-energy cost required for the extraction of their metabolites has kept questioning on possible industrial upgrading. The aim of this study was to evaluate the effect of temperature, solvent/biomass, NaOH concentration and thermal pretreatment of the biomass in a 2-cycle carbohydrate and protein extraction system. Results shown that best conditions for carbohydrates extraction are achieved at a solvent concentration of 3.67 M, 55°C and a solvent/biomass ratio of 30mL/g. On the other side, the best conditions for protein were 3 M, 85°C and 45 mL/g. The efficiencies achieved under these conditions were 95% for carbohydrates and 98% for proteins. Using the best extraction conditions for each metabolite a thermal pre-treatment was performed at 25°C, 75°C and 105°C. Results indicate that highest efficiencies were achieved with dry biomass pretreated at 105°C, with values of 95% for carbohydrates and 98% for proteins
Infusion extractor
This invention relates to an apparatus and method of removing desirable constituents from an infusible material by infusion extraction. A piston operating in a first chamber draws a solvent into the first chamber where it may be heated, and then moves the heated solvent into a second chamber containing the infusible material, where infusion extraction takes place. The piston then moves the solvent containing the extract through a filter into the first chamber, leaving the extraction residue in the second chamber. The method is applicable to operation in low or micro-gravity environments
Screening the effect of four ultrasound-assisted extraction parameters on hesperidin and phenolic acid content of aqueous citrus pomace extracts
Polyphenols of citrus by-products, due to their antioxidant and antimicrobial activities, could be valorized by pharmaceutical and food industries, adding a value to the citrus processing companies. A number of studies have investigated the effect of ultrasound-assisted extraction (UAE) conditions on the recovery of phenolics derived from citrus waste using both organic solvents or mixed aqueous solvent systems. To maximize efficiency, UAE conditions should be tailored to the physical parameters of the solvent(s) employed. The aim of this study was to investigate the effect of four UAE parameters: particle size (1.40–2.80 mm), extraction time (10–60 min), extraction temperature (23–50 °C) and ultrasonic power (150–250 W) on the simultaneous recovery of p-coumaric acid, caffeic acid, chlorogenic acid, and hesperidin from citrus waste using pure water as a solvent. High-performance liquid chromatography (HPLC) was employed for the identification and quantification of the cited compounds. Particle size was determined to be an important parameter affecting compound recovery, with the exception of chlorogenic acid. A particle size of 1.40 mm resulted in the highest recovery of p-coumaric and caffeic acids (0.25 and 0.58 mg/g, respectively), while higher hesperidin yields were achieved from the particle sizes of 2.00 and 1.40 mm (6.44 and 6.27 mg/g, respectively). Extraction temperature significantly affected only the recovery of the flavanone glycoside (P<0.05). As the extraction temperature increased from 30 to 50 °C the recovery of hesperidin increased from 6.59 to 7.84 mg/g, respectively. Neither extraction time nor ultrasonic power significantly affected the recovery of any individual phenolic compound
Extraction of anthocyanins and total phenolic compounds from açai (euterpe oleracea mart.) using an experimental design methodology. part 1: Pressurized liquid extraction
Currently, açai is one of the most important fruits present in the world. Several studies have demonstrated its high content in phenolic compounds and anthocyanins. Both of them are responsible of interesting properties of the fruit such as anti-inflammatory, antioxidant or anticancer. In the present study, two optimized pressurized liquid extraction (PLE) methods have been developed for the extraction of anthocyanins and total phenolic compounds from açai. A full factorial design (Box-Behnken design) with six variables (solvent composition (25%-75% methanol-in-water), temperature (50-100°C), pressure (100-200 atm), purge time (30-90 s), pH (2-7) and flushing (50%-150%)) were employed. The percentage of methanol in the extraction solvent was proven to be the most significant variable for the extraction of anthocyanins. In the case of total phenolic compounds, the extraction temperature was the most influential variable. The developed methods showed high precision, with relative standard deviations (RSD) of less than 5%. The applicability of the methods was successfully evaluated in real samples. In conclusion, two rapid and reliable PLE extraction methods to be used for laboratories and industries to determine anthocyanins and total phenolic compounds in açai and its derived products were developed in this work
Extraction of bioactive polyphenols with high antioxidant activity from bilberry (Vaccinium myrtillus L.) processing waste
Bioactive polyphenols were extracted from the peel fraction of bilberry processing waste using aqueous ethanol as solvent. A response surface methodology was used to evaluate the effects of liquid-to-solid ratio (R), solvent composition (C), extraction time (E) and temperature (T) on the extraction yield. The following optimal conditions were determined: R = 30 mL/g, C = 57%, E = 160 min, T = 40 °C. Phenolic extracts with a polyphenol content of 83.75 ± 4.16 mg GAE/g and an antioxidant activity of 7.64 ± 0.43 mmol TE/g were also produced using a batch extractor operating under optimal process conditions
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