Supercritical Fluid Extraction versus Traditional Solvent Extraction of Caffeine from Tea Leaves: A Laboratory-Based Case Study for an Organic Chemistry Course

2012 ◽  
Vol 89 (10) ◽  
pp. 1327-1330 ◽  
Author(s):  
Peter M. Schaber ◽  
Judith E. Larkin ◽  
Harvey A. Pines ◽  
Kelly Berchou ◽  
Elizabeth Wierchowski ◽  
...  
Keyword(s):  
Organic Chemistry ◽  
Solvent Extraction ◽  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Tea Leaves ◽  
Fluid Extraction

scholarly journals Assessment of Conventional Solvent Extraction vs. Supercritical Fluid Extraction of Khella (Ammi visnaga L.) Furanochromones and Their Cytotoxicity

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1290
Author(s):  
Noha Khalil ◽  
Mokhtar Bishr ◽  
Mohamed El-Degwy ◽  
Mohamed Abdelhady ◽  
Mohamed Amin ◽  
...  
Keyword(s):  
Solvent Extraction ◽  
Cytotoxic Activity ◽  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Water Extract ◽  
Renal Stones ◽  
Pharmaceutical Products ◽  
Fluid Extraction ◽  
Ammi Visnaga ◽  
Conventional Solvent Extraction

Background: Khella (Ammi visnaga Lam.) fruits (Apiaceae) are rich in furanochromones, mainly khellin and visnagin, and are thus incorporated in several pharmaceutical products used mainly for treatment of renal stones. Methods: The objective of this study was to compare the yield of khellin and visnagin obtained using different conventional solvents and supercritical fluid extraction (SCFE) with carbon dioxide (containing 5% methanol as co-solvent). Water, acetone and ethanol (30% and 95%) were selected as conventional solvents. Results: Highest extract yield was obtained from 30% ethanol (15.44%), while SCFE gave the lowest yield (4.50%). However, the percentage of furanochromones were highest in SCFE (30.1%), and lowest in boiling water extract (5.95%). HPLC analysis of conventional solvent extracts showed other coumarins that did not appear in supercritical fluid extraction chromatogram due to non-selectivity of solvent extraction. Ammi visnaga extracts as well as standard khellin and visnagin were tested for their cytotoxic activity using sulforhodamine B assay on breast cancer (MCF-7) and hepatocellular carcinoma (Hep G2) cell lines. Results revealed a strong cytotoxic activity (IC50 < 20 µg/mL) for the SCFE and standard compounds (khellin and visnagin) (IC50 ranging between 12.54 ± 0.57 and 17.53 ± 1.03 µg/mL). However, ethanol and acetone extracts had moderate cytotoxic activity (IC50 20–90 µg/mL) and aqueous extract had a weak activity (IC50 > 90 µg/mL). Conclusions: Thus, supercritical fluid extraction is an efficient, relatively safe, and cheap technique that yielded a more selective purified extract with better cytotoxic activity.

scholarly journals Isolation of Chloramphenicol from Whole Eggs by Supercritical Fluid Extraction with In-Line Collection

1999 ◽  
Vol 82 (6) ◽  
pp. 1334-1339 ◽  
Author(s):  
John W Pensabene ◽  
Walter Fiddler ◽  
Dan J Donoghue
Keyword(s):  
Solvent Extraction ◽  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Extraction Method ◽  
Gas Flow ◽  
Extraction Procedure ◽  
The United States ◽  
Fluid Extraction ◽  
Solvent Extraction Method ◽  
Significant Difference

Abstract Egg consumption, at more than 65 billion per year in the United States, represents a potentially significant source of exposure to drug residues, particularly if the laying hens are treated with antimicrobial compounds or fed a diet containing medicated feed. Residues resulting from the use of chloramphenicol (CAP) is especially problematic if this compound is not used in accordance with national registration, e.g., for the control of Salmonella microorganisms in poultry. The most commonly used methods for the determination of CAP in biological samples require the use of large amounts of organic solvent. As a result, a less solvent intensive supercritical fluid extraction (SFE) method was developed for CAP in whole chicken eggs, and the results were compared with those for a solvent extraction procedure. In the SFE method, the egg sample is extracted with supercritical CO2 (without a modifier) at 10 000 psi (680 bar), 80°C, and an expanded gas flow rate of 3.0 L/min to a total volume of 150 L. The CAP is trapped in-line on a Florisil sorbent bed. The CAP is eluted post-SFE by using the liquid chromatographic mobile phase solvent (water-methanol), and determined on a C8 column with ultraviolet detection at 280 nm. Recovery from eggs fortified at the 10 ppb level (n = 6) was 81.2 ± 4.3%. To obtain eggs containing incurred CAP, hens were given a single daily dose of 75 mg CAP (orally by gelatin capsule) for 2 consecutive days, and the eggs were collected over a 12-day period. The mean value for “normally incurred” CAP in the eggs (n = 17) analyzed by SFE ranged from none detected to 174.5 ppb, with an overall mean of 60.5 ppb, compared with a mean of 60.4 ppb for the solvent extraction method. No significant difference in results was found between methods. However, the SFE method is more rapid, uses less solvent, and gives recoveries similar to those for the solvent extraction method, making it ideal for regulatory monitoring.

Sign in / Sign up

Export Citation Format

Share Document