ABSTRACT
Antioxidants from orange juice are isolated by the use of countercurrent supercritical fluid extraction (CC-SFE) and characterized by reversed-phase liquid chromatography (RPLC) coupled to mass spectrometry (MS) and diode-array detection (DAD). A pilot-scale SFE plant equipped with a packed column has been employed for countercurrent extraction and fractionation of raw orange juice with carbon dioxide. Several experiments have been performed in order to study the effect of the countercurrent conditions on the content of antioxidative compounds. In this study, the main variable that has been considered is the solvent-to-feed ratio (S/F) because it plays an essential role in the extraction efficiency. The values tested covered a wide range of sample and solvent (CO(2)) flow rates. In each experimental run, two different extracted fractions and the residual nonextracted juice were obtained and characterized. Different flavonoids have been identified in the fractions obtained after CC-SFE. The possibility of using this process for antioxidant compounds enrichment is discussed.
Subject(s)
Antioxidants/isolation & purification , Beverages/analysis , Citrus/chemistry , Benzoic Acid/analysis , Countercurrent Distribution , Hesperidin/analysisABSTRACT
A procedure for the recovery of aromatic extracts from distilled alcoholic beverages by means of a countercurrent supercritical fluid extraction (CC-SFE) on a pilot plant scale is studied. The beverage is directly in contact with the carbon dioxide current in a packed column, and the extracts are recovered in two different fractionation cells, where the depressurization occurs. The proposed method allows the selective extraction of aromatic components of the brandy flavor, rendering a high-value concentrated extract and a colored residue without brandy aroma. The content in ethanol of the aromatic extract can be modified by tuning the extraction/fractionation conditions, rendering from 15 to 95% recovery. The effect of the main variables, including extraction pressure and quality of extracting CO(2), has been tested.
Subject(s)
Alcoholic Beverages/analysis , Counterimmunoelectrophoresis/methods , Carbon Dioxide , Chemical Fractionation , Color , Odorants , PressureABSTRACT
In order to have a diagnostic test for invasive candidiasis, an immunofluorescent assay (IFA) in buffy coat was developed and evaluated. This test was compared to buffy coat culture and blood culture. The study was divided into two parts: evaluation of the diagnostic test in a rabbit model, and for diagnosis in patients at high risk for invasive candidiasis. Part I: Rabbits were experimentally infected. Of 13 rabbits with disseminated candidiasis blood was drawn from central venous catheter and from peripheral veins. From catheters, Candida was detected in 13/13, 10/13 and 8/13, by buffy coat culture, IFA, and blood culture, respectively. From peripheral veins, Candida was detected in 10/10 by buffy coat cultures, in 6/10 by IFA and in 3/10 by blood cultures. The gold standard was histopathological diagnosis; sensitivity for IFA was 60% with peripheral blood and 76% with catheter blood samples. Part II: IFA and blood cultures were compared in clinical samples from hospitalized children. Forty patients were included. Candida was isolated from blood cultures in four patients whereas IFA detected Candida in 22 patients. Differences were statistically significant (p < 0.05). We conclude that IFA in buffy coat smears is a reliable test to detect candidemia, and would be a useful tool to help physicians with treatment decisions with amphotericin B.
Subject(s)
Candidiasis/diagnosis , Fluorescent Antibody Technique, Indirect , Animals , Bacteremia/diagnosis , Candidiasis/blood , Child , Cross-Sectional Studies , Humans , Leukocytes/chemistry , Male , Predictive Value of Tests , Prospective Studies , Rabbits , Time FactorsABSTRACT
We report a case of a female infant, from Acapulco Guerrero, Mexico. She had been sick for 45 days, with diarrhea and general malaise, fever during the last 20 days; at physical examination she was pale, with abdominal distention and hepatosplenomegaly. She had leukopenia, thrombocytopenia and anemia. The microscopic findings in the bone marrow sample were intracytoplasmic and extracellular bodies. Both bone marrow and blood cultures were positive for Histoplasma capsulatum. Seventy three pediatric cases of diseminated histoplasmosis have been described in the medical literature since 1934 to 1988. It is know that only about 1% of the persons that become infected will develop a diseminated disease.
