Flavonol content varies among black currant cultivars.

Flavonoids and related plant compounds in fruits and vegetables are of particular importance as they have been found to possess antioxidant and free radical scavenging activity. The HPLC-based quantitative procedure, with improved extraction and hydrolysis, was used to analyze the content of the flavonols quercetin, myricetin, and kaempferol in 10 black currant cultivars from organic farms and in 5 cultivars from conventional farms. Myricetin was the most abundant flavonol, and its amount varied significantly among cultivars, from 8.9 to 24.5 mg x 100 g(-1) (fresh weight). The quercetin levels in black currant also varied widely among the cultivars, from 5.2 to 12.2 mg x 100 g(-1). The kaempferol levels in black currant cultivars were low, ranging from 0.9 to 2.3 mg x 100 g(-1). The sum of these major flavonols varied widely among black currant cultivars. No consistent differences in the contents of flavonols were found between the same black currant cultivars grown in organic and conventional ways. The high variability in the levels of flavonols in different cultivars offers possible avenues for identifying and selecting cultivars rich in certain flavonols for the special production of berries for industrial use.

Phenolic compounds in berries of black, red, green, and white currants (Ribes sp.).

Multiple health benefits associated with phenolic compounds have raised the interest in the contents of these plant metabolites in foods. Several phenolic compounds were quantified from berries of Ribes nigrum (black and green currants) and Ribes x pallidum (red and white currants), by using sequential extraction with ethyl acetate and methanol and an optimized reversed-phase HPLC method with diode array detection. The highest contents of anthocyanins (3,011 mg/kg fresh weight, expressed as the aglycon) and flavonol glycosides (100 mg/kg) were found in black currant. The lack of anthocyanins in the colorless (green, white) berries was associated with increased levels of phenolic acids, especially p-coumaric acid (80 mg/kg in green currant vs. 45 mg/kg in black currant) and 4-hydroxybenzoic acid (18 mg/kg in white currant vs. 3 mg/kg in red currant). Previously, proanthocyanidins have not been quantified from berries. This study showed that the contents of extractable (22-41 mg/kg) and nonextractable proanthocyanidins (32-108 mg/kg) are comparable to those of other phenolics, with the exception of anthocyanins in black currant. Our results suggest that anthocyanins dominate in black and red currants, whereas proanthocyanidins and phenolic acids are the predominant phenolic compounds in green and white currants.

Content of the flavonols myricetin, quercetin, and kaempferol in finnish berry wines.

The amounts of myricetin, quercetin, and kaempferol were analyzed in 16 red and 2 white berry and grape wines after acid hydrolysis using an RP-HPLC method with diode array detection. The red berry wines analyzed were made mainly from black currant, crowberry, and bog whortleberry, i.e., berries rich in flavonols. The red grape wines were made mainly from Cabernet Sauvignon or Merlot grapes in several countries. The white wines studied were gooseberry and white currant wines and Chardonnay and Riesling wines. The amount of myricetin ranged from 3.8 to 22.6 mg L(-1) in red berry wines and from 0 to 14.6 mg L(-1) in red grape wines. The amount of quercetin was from 2.2 to 24.3 mg L(-1) red berry wines and from <1.2 to 19.4 mg L(-1) in red grape wines. Low levels of kaempferol were found in all red berry wines and in 9 red grape wines. The total concentration of these flavonols was from 6 to 46 mg L(-1) (mean 20 mg L(-1)) in red berry wines and from 4 to 31 mg L(-1) (mean 15 mg L(-1)) in red grape wines. Small amounts of quercetin were found in white currant and gooseberry wines, whereas no flavonols were detected in white grape wines. These results demonstrate that the contents of flavonols in red

Acid-catalyzed isomerization of fucosterol and delta5-avenasterol.

This work shows that fucosterol, delta5-avenasterol, and similar ethylidene-side chain sterols can undergo acid-catalyzed isomerization to give a mixture of five isomers. Four isomers formed from fucosterol were analyzed, using gas chromatography-mass spectrometry, and were characterized as delta5-avenasterol, two delta5,23-stigmastadienols, and delta5,24(25)-stigmastadienol. When the unsaponifiables fraction from oat oil was subjected to acid hydrolysis, the two delta5,23-stigmastadienol isomers and delta5,24(25)-stigmastadienol were detected while fucosterol coeluted with sitosterol. Interisomerization of ethylidene-side chain sterols represents a limitation to the use of the acid hydrolysis method in the determination of sterols in food and other plant materials rich in these sterols, e.g., oat lipids.

Profiling of hot surfaces by pulsed time-of-flight laser range finder techniques.

The possibilities for using the pulsed time-of-flight (TOF) laser radar technique for hot refractory lining measurements are examined, and formulas are presented for calculating the background radiation collected, the achievable signal-to-noise ratio (SNR), and the measurement resolution. An experimental laser radar device is presented based on the use of a laser diode as a transmitter. Results obtained under real industrial conditions show that a SNR of 10 can be achieved at measurement distances of up to 15-20 m if the temperature of the converter is 1400 °C and the peak power of the laser diode used is 10 W. The single-shot resolution is about 60 mm (sigma value), but it can be improved to millimeter range by averaging techniques over a measurement time of 0.5 s. A commercial laser radar profiler based on the experimental laser radar device is also presented, and results obtained with it in real measurement situations are shown. These measurements indicate that it is possible to use the pulsed TOF laser radar technique in demanding measurement applications of this kind to obtain reliable data on the lining wear rate of a hot converter in a steel works.

Pulmonary berylliosis: report on a fatal case.

A fatal case of pulmonary berylliosis in a 59-year-old male is described. Three months after a heavy exposure to the dust of broken fluorescent light bulbs he developed severe respiratory distress with bilateral lower zone opacities on the chest radiograph. Histological examination of a lung biopsy revealed inflammatory changes with a granulomatous component and some necrosis. The diagnosis of berylliosis was confirmed by determination of beryllium in lung tissue by chemical analysis. Two years after the onset of symptoms the patient died of respiratory failure.

Pulmonary deposits of titanium dioxide in cytologic and lung biopsy specimens. Light and electron microscopic x-ray analysis.

Although titanium dioxide (TiO2) is widely used in industry, its biologic effects have not been determined. In the present investigation, open lung biopsy samples and sputum specimens from three former TiO2 factory workers and bronchial aspirations from seven TiO2 factory workers were analyzed by conventional and x-ray microanalytic light and electron microscopic methods. These studies showed that in the alveolar macrophages, lysosomes contained a significant amount of titanium as well as smaller amounts of silicon, aluminum, iron, and potassium. It appeared that titanium dioxide was situated in round or oval-shaped particles whereas silica or silicon compounds were localized in separate, more rectangular structures. There fore, the adverse effects may be induced by such quartz or silicon compounds. The latter are utilized as covering substances in the manufacture of TiO2 pigment.