Improving the recovery of phenolic compounds from spent coffee grounds by using hydrothermal delignification coupled with ultrasound assisted extraction

The aim of this study was to investigate and compare the effects of different extraction techniques (high hydrostatic pressure-assisted extraction (HHPE), ultrasound-assisted extraction (UAE), and classical solvent extraction (CSE)) on phenolic compounds from spent coffee grounds (SCG). Different HHPE parameters (300, 400 and 500 MPa at 25 °C for 5, 10 and 15 min) and UAE parameters (40%, 50%, and 60% amplitude at 25 °C for 5, 10 and 15 min) were used. These techniques were compared with CSE (at 50 °C for 30 min) according to total phenolic content (TPC), antioxidant activity (AA), high-performance liquid chromatography (HPLC), scanning electron microscopy (SEM), and infrared (IR) spectroscopy. The results showed that eco-friendly techniques increased the TPC and AA compared to CSE and morphological changes were verified by SEM results. Furthermore, chlorogenic and caffeic acid were also quantified by using HPLC. Chlorogenic acid was found as the main phenolic compound in spent coffee grounds (SCG). The highest chlorogenic acid was detected as 85.0 ± 0.6 mg/kg FW with UAE at 60% amplitude for 15 min. In brief, for the extraction of phenolic compounds from waste SCG eco-friendly techniques such as HHPE and/or UAE were more convenient than CSE.

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Optimization of Ultrasound-Assisted Extraction of Spent Coffee Grounds Oil Using Response Surface Methodology

Processes ◽

10.3390/pr9112085 ◽

2021 ◽

Vol 9 (11) ◽

pp. 2085

Author(s):

Malek Miladi ◽

António A. Martins ◽

Teresa M. Mata ◽

Miguel Vegara ◽

María Pérez-Infantes ◽

...

Keyword(s):

Health And Safety ◽

Oil Extraction ◽

Extraction Yield ◽

Operating Conditions ◽

Extraction Time ◽

Spent Coffee Grounds ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Coffee Grounds ◽

Ultrasound Assisted

Spent coffee grounds (SCGs) generated in coffee processing for beverages and other products are a very significant organic residue that needs to be properly treated. Waste valorization via oil extraction has the potential to obtain compounds that can be used for producing biodiesel or other high-value products, such as polymers. This work focuses on the ultrasound-assisted extraction of SCG oil using n-hexane as a solvent. Three key process parameters are analyzed: temperature, extraction time, and liquid/solid (L/S) rate of solvent, using a central composite rotatable design (CCRD), an analysis that, to the author’s knowledge, is not yet available in the literature. The data were analyzed using the software StatSoft STATISTICA 13.1 (TIBCO Software Inc., Palo Alto, CA, USA). Results show that all parameters have a statistical influence on the process performance (p < 0.05), being the L/S ratio the most significant, followed by extraction time and temperature. An analysis of variance (ANOVA) showed that the empirical model is a good fit to the experimental data at a 95% confidence level. For the range of conditions considered in this work, the optimal operating conditions for obtaining an oil extraction yield in the range of 12 to 13%wt are a solvent L/S ratio of around 16 mL g−1, for a temperature in the range of 50 to 60 °C, and the longest contact time, limited by the process economics and health and safety issues and also, by the n-hexane boiling temperature.

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Innovative Extraction Techniques for the Optimum Extraction of Phenolic Compounds from Peanut Meal and Evaluation of Their Biological Activities

Advances in Nutrition & Food Science ◽

10.33140/anfs.04.02.2 ◽

2019 ◽

Vol 4 (2) ◽

Keyword(s):

Phenolic Compounds ◽

Carcinoma Cell ◽

Biological Activities ◽

Peanut Meal ◽

Ultrasound Assisted Extraction ◽

Carcinoma Cell Lines ◽

Assisted Extraction ◽

Phenolic Extract ◽

Ultrasound Assisted ◽

Water Ratio

There is a worldwide demand for phenolic compounds (PC) because they exhibit several biological activities. This work aimed at extracting phenolic compounds from peanut meal. The methods of extraction were mainly: conventional solvent extraction (traditional methods) and ultrasound assisted extraction (recent methods) and comparing their results. Peanut meal (PM) was prepared by defatting with n-hexane, and then extracted by the two previous methods. First, the conventional solvents used were 80% methanol, ethanol, acetone, isopropanol, and distilled water. Then studied Different parameters such as meal: water ratio, also the effect of temperature and the pH on the extraction process. Second, ultrasonic assisted extractions (USAE), the parameters investigated were temperature, time and speed of sonication. Finally, all the extracts were analyzed by HPLC for their phenolic contents. Results indicated that the highest extracted PC achieved by solvents was in distilled water where 1:100, Meal: Water ratio which extracted 40 mg PC / g PM at 30& 35°C. Highest extracted PC was achieved by alkaline medium at pH 12 more than acidic and neutral medium. While (USAE) at speed 8 ultrasonication and temperature 30ᵒC, extracted 49.2mg PC /g PM. Sothe ultrasound assisted extraction exhibited great influence on the extraction of phenolic compounds from peanut meal. The ultrasonic peanut extract was examined for its antioxidant, antimicrobial and anticarcinogenic activities. The antioxidant activity of PM phenolic extract prepared by ultrasonic technique, was measured by, β-carotene, and DPPH methods, and reducing antioxidant power. Results revealed values: 84.57, 57.72 and 5960 respectively. The PM extract showed different levels of antimicrobial activity against the pathogenic bacteria used. As for the anticarcinogenic effect PM phenolic extract most effective on inhibiting colon carcinoma and lung carcinoma cell lines with IC50 = 20.7 and 20.8 µ/ml., respectively. This was followed by intestinal carcinoma and liver carcinoma cell lines with IC50= 39.6 and 40.2µ/ml.

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Greener ultrasound-assisted extraction of bioactive phenolic compounds in Croton heliotropiifolius Kunth leaves

Microchemical Journal ◽

10.1016/j.microc.2020.105525 ◽

2020 ◽

Vol 159 ◽

pp. 105525 ◽

Cited By ~ 1

Author(s):

Cheila B. do C. de Sousa ◽

Gilvanda L. dos Anjos ◽

Rafaela S.A. Nóbrega ◽

Andréia da S. Magaton ◽

Fabrício M. de Miranda ◽

...

Keyword(s):

Phenolic Compounds ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Ultrasound Assisted

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Microwave-Assisted Extraction and Ultrasound-Assisted Extraction of Bioactive Compounds from Grape Pomace

International Journal of Food Engineering ◽

10.1515/ijfe-2019-0191 ◽

2020 ◽

Vol 16 (1-2) ◽

Cited By ~ 2

Author(s):

Cassiano Brown da Rocha ◽

Caciano Pelayo Zapata Noreña

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Bioactive Compounds ◽

Grape Pomace ◽

Total Phenolic ◽

Microwave Assisted Extraction ◽

Ultrasound Assisted Extraction ◽

Microwave Assisted ◽

Assisted Extraction ◽

Ultrasound Assisted

AbstractThe grape pomace is a by-product from the industrial processing of grape juice, which can be used as a source of bioactive compounds. The aim of this study was to separate the phenolic compounds from grape pomace using an acidic aqueous solution with 2 % citric acid as a solvent, using both ultrasound-assisted extraction, with powers of 250, 350 and 450 W and times of 5, 10 and 15 min, and microwave-assisted extraction using powers of 600, 800 and 1,000 W and times of 5, 7 and 10 min. The results showed that for both methods of extraction, the contents of total phenolic compounds and antioxidant activity by ABTS and DPPH increased with time, and microwave at 1,000 W for 10 min corresponded to the best extraction condition. However, the contents of phenolic compounds and antioxidant activity were lower than exhaustive extraction using acidified methanol solution.

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Effect of solvent composition and its interaction with ultrasonic energy on the ultrasound-assisted extraction of phenolic compounds from Mango peels (Mangifera indica L.)

Food and Bioproducts Processing ◽

10.1016/j.fbp.2020.03.011 ◽

2020 ◽

Vol 122 ◽

pp. 41-54 ◽

Cited By ~ 3

Author(s):

Tania Martínez-Ramos ◽

José Benedito-Fort ◽

Nicholas James Watson ◽

Irving I. Ruiz-López ◽

Gamaliel Che-Galicia ◽

...

Keyword(s):

Phenolic Compounds ◽

Mangifera Indica ◽

Solvent Composition ◽

Ultrasonic Energy ◽

Ultrasound Assisted Extraction ◽

Effect Of Solvent ◽

Assisted Extraction ◽

Ultrasound Assisted ◽

Mango Peels

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Optimization of Ultrasound-Assisted Extraction via Sonotrode of Phenolic Compounds from Orange By-Products

Foods ◽

10.3390/foods10051120 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1120

Author(s):

María del Carmen Razola-Diaz ◽

Eduardo Jesús Guerra-Hernández ◽

Celia Rodríguez-Pérez ◽

Ana María Gómez-Caravaca ◽

Belén García-Villanova ◽

...

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

High Performance ◽

Phenolic Content ◽

Orange Peel ◽

Polar Compounds ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Quantitative Analyses ◽

Ultrasound Assisted

Orange peel is the main by-product from orange juice industry. It is a known source of bioactive compounds, mostly phenolic compounds, and it has been widely studied for its healthy activities. Thus, this research focuses on the establishment of ultrasound-assisted extraction of phenolic compounds in orange peel using a sonotrode. For this purpose, a Box–Behnken design of 27 experiments was carried out with four independent factors—ratio ethanol/water (v/v), time (min), amplitude (%), and pulse (%). Quantitative analyses of phenolic compounds were performed and the antioxidant activity was measured by ABTS and DPPH methods. The validity of the experimental design was confirmed by ANOVA and the optimal sonotrode extraction conditions were obtained by response surface methodology (RSM). The extracts obtained in the established conditions were analyzed by High Performance Liquid Chromatography (HPLC) coupled to mass spectrometer detector and 74 polar compounds were identified. The highest phenolic content and antioxidant activity were obtained using 45/55 ethanol/water (v/v), 35 min, amplitude 90% (110 W), and pulse 100%. The established method allows an increment of phenolics recovery up to 60% higher than a conventional extraction. Moreover, the effect of drying on phenolic content was also evaluated.

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