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PubMed2002

[Identification of chemical structure of antibacterial components against Legionella pneumophila in a coffee beverage].

We previously reported that certain constituents in brewed coffee exhibited antibacterial activities against a strain of Legionella pneumophila. The constituents showing antibacterial activities were included only in extracts cold with water or hot water. To determine the antibacterial substances in coffee extract, the extract was fractionated by HPLC using a UV/photodiode array detector. The optimum HPLC conditions for analysis were UV wavelength of 250 nm and eluents of methanol/acetic acid (10/90), pH 3.0. When several fractions separated by HPLC were investigated for antibacterial activities against L. pneumophila, it was found that three peak fractions exhibited strong antibacterial activities. Each product from these fractions was analyzed by NMR and LC-mass spectrometry, and the chemical structure of each was determined. It was shown that the antibacterial substances was were protocatechuic acid (3,4-dihydroxy benzoic acid), chlorogenic acid, and caffeic acid.

Beverages↗
PubMed2006

Transfer of multivariate classification models between laboratory and process near-infrared spectrometers for the discrimination of green Arabica and Robusta coffee beans.

Analogous to the situation found in calibration, a classification model constructed from spectra measured on one instrument may not be valid for prediction of class from spectra measured on a second instrument. In this paper, the transfer of multivariate classification models between laboratory and process near-infrared spectrometers is investigated for the discrimination of whole, green Coffea arabica (Arabica) and Coffea canefora (Robusta) coffee beans. A modified version of slope/bias correction, orthogonal signal correction trained on a vector of discrete class identities, and model updating were found to perform well in the preprocessing of data to permit the transfer of a classification model developed on data from one instrument to be used on another instrument. These techniques permitted development of robust models for the discrimination of green coffee beans on both spectrometers and resulted in misclassification errors for the transfer process in the range of 5-10%.

Algorithms↗
PubMed1986

Bronchodilator effects of caffeine in coffee. A dose-response study of asthmatic subjects.

Although caffeine is a universal drug and has multiple pharmacologic and physiologic actions in man, there are surprisingly few objective data about its effect on pulmonary function. We conducted a short-term, double-blind, randomized crossover study in nine asthmatic adults who ingested decaffeinated coffee containing varying amounts of added caffeine (mean of 0.2,2.5,5.6, and 7.2 mg/kg of body weight) on different days. The subjects also ingested decaffeinated coffee and aminophylline (200 mg) on a separate day of study. Baseline and post-drug determinations of serum levels of caffeine and theophylline, forced expired volume and flow, specific airway conductance (Gaw/VL), vital signs, and reported symptoms were obtained. Peak increases in serum caffeine concentrations (mean, 12.4 micrograms/ml +/- 1.5 micrograms/ml) occurred 45 minutes following the highest dose of caffeine (7.2 mg/kg), whereas the peak theophylline level (mean 3.8 micrograms/ml +/- 0.4 micrograms/ml) occurred 90 minutes following oral administration of aminophylline (mean theophylline, 2.6 mg/kg). Comparable peak increases in the forced expiratory volume in one second (FEV1), the forced expiratory flow during the middle half of the forced vital capacity (FEF25-75%), and Gaw/VL occurred at 120 minutes following aminophylline and the highest dose of caffeine, indicating that caffeine is an effective bronchodilator but is only 40 percent as active as an equivalent molar dose of theophylline. Regression analysis revealed statistically significant dose-response relationships between peak increases in serum caffeine concentrations and increases in FEV1, FEF25-75%, and Gaw/VL from baseline values. These findings have diagnostic and therapeutic implications regarding the use of caffeine prior to tests of pulmonary function and as a dietary agent, alone or in combination with theophylline.

Administration, Oral↗
PubMedDate not supplied

Relationship between coffee husk caffeine degradation and respiration of Aspergillus sp. LPBx in solid-state fermentation.

Studies were carried out in a packed-bed column fermentor using coffee husk as substrate in order to verify a relationship between caffeine degradation and the respiration of Aspergillus sp. LPBx. Fermentation conditions were optimized by using factorial design experiments. The kinetic study showed that the caffeine degradation was related to the development of mold and its respiration and also with the consumption of reducing sugars present in coffee husk. From the values obtained experimentally for oxygen uptake rate and CO2 evolved, we determined a biomass yield of 3.811 g of biomass/g of consumed O2 and a maintenance coefficient of 0.0031 g of consumed O2/(g of biomass x h). The maximum caffeine degradation achieved was 90%.

Aspergillus↗
PubMedDate not supplied

Gibberellic acid production by solid-state fermentation in coffee husk.

Five strains of Gibberella fujikuroi and one of Fusarium moniliforme were screened for the production of gibberellic acid (GA3) in coffee husk, and based on the results, one strain, G. fujikuroi LPB-06, was selected. The comparative production of GA3 by solid-state fermentation and submerged fermentation indicated better productivity with the former technique, mainly with pretreated substrate. The GA3 accumulation was 6.1 times higher in the case of solid-state fermentation. Considering the C:N relation, higher yields of GA3 were achieved using a mixed substrate comprising coffee husk and cassava bagasse (7:3, dry wt), increasing the results twice. Supplementation of an optimized saline solution containing 0.03% FeSO4 and 0.01% (NH4)2SO4 enhanced the accumulation of GA3 1.7 times in the fermented substrate. Under the finally optimized condition, the culture gave a maximum of 492.5 mg of GA3/kg of dry substrate, with a pH of 5.3, moisture of 75%, and incubation temperature of 29 degrees C. GA3 yield was almost 13 times more than the initial results.

Chromatography, High Pressure Liquid↗
PubMed1984

Consumption of coffee or tea and symptoms of anxiety.

The relationship of consumption of coffee or tea to self-reported symptoms of anxiety is examined with data from the detailed examination component of the National Center for Health Statistics Health and Nutrition Examination Survey. Among this nationwide sample of 3,854 respondents, there was no significant association between consumption of coffee or tea and symptoms of anxiety.

Aged↗
PubMed1989

A case-control study of pancreatic cancer and cigarettes, alcohol, coffee and diet.

A pancreatic cancer case-control study was conducted in the Minneapolis-St. Paul area. Family members were interviewed about the subject's usage of cigarettes, alcohol, coffee, and other dietary factors in the two years prior to death (cases, n = 212) or prior to interview (controls, n = 220). The adjusted odds ratio for two packs or more of cigarettes per day was 3.92 (95% CI = 1.18, 13.01) and four or more drinks per day OR 2.69 (95% CI = 1.00, 7.27). Coffee was not a risk factor (seven cups or more per day; OR 0.58 (95% CI = 0.27, 1.27). A positive trend was observed for beef and pork consumption, and a negative trend from cruciferous vegetables.

Adult↗
PubMed1992

Cigarette, alcohol, and coffee consumption and prematurity.

We analyzed data from a survey of occupational and other factors in pregnancy to assess the effects of cigarette, alcohol, and coffee consumption on pregnancy outcome. The risk of low birth weight for gestational age was found to increase substantially with smoking. Occasional consumers of alcohol had a slightly reduced risk relative to total abstainers. In more frequent drinkers, there was a small increase in risk. Risk increased slightly with coffee consumption.

Adult↗
PubMed1992

Cigarette, alcohol, and coffee consumption and congenital defects.

We analyzed data from a survey of occupational and other factors and pregnancy outcome to assess the effects of cigarette, alcohol, and coffee consumption. There was no evidence of an association between any congenital defect and smoking. Results for alcohol and coffee consumption were largely negative, but there was a weak association with musculoskeletal defects in babies born to women who drank one or more alcoholic drinks a day.

Alcohol Drinking↗
PubMedDate not supplied

Contrasting nitrate adsorption in Andisols of two coffee plantations in Costa Rica.

Fertilizer use in coffee plantations is a suspected cause of rising ground water nitrate concentrations in the ground water-dependent Central Valley of Costa Rica. Nitrate adsorption was evaluated beneath two coffee (Coffea arabica L.) plantations in the Central Valley. Previous work at one site had identified unsaturated zone nitrate retardation relative to a tritium tracer. Differences in nitrate adsorption were assessed in cores to 4 m depth in Andisols at this and one other plantation using differences in KCl- and water-extractable nitrate as an index. Significant adsorption was confirmed at the site of the previous tracer test, but not at the second site. Anion exchange capacity, X-ray diffraction data, extractable Al and Si, and soil pH in NaF corroborated that differences in adsorption characteristics were related to subtle differences in clay mineralogy. Soils at the site with significant nitrate adsorption showed an Al-rich allophane clay content compared with a more weathered, Si-rich allophane and halloysite clay mineral content at the site with negligible adsorption. At the site with significant nitrate adsorption, nitrate occupied less than 10% of the total anion adsorption capacity, suggesting that adsorption may provide long-term potential for mitigation or delay of nitrate leaching. Evaluation of nitrate sorption potential of soil at local and landscape scales would be useful in development of nitrogen management practices to reduce nitrate leaching to ground water.

Adsorption↗
PubMed1995

The chemical origin of free radicals in coffee and other beverages.

Sugars or carbohydrates are identified as the source of free radicals in coffees, ersatz coffees, a number of other food flavouring and colouring agents formed by processes involving heating, and in beers and stouts. The radicals are not derived from phenolic constituents, in contrast to those in wine, and are unlikely to be due solely to the occurrence of Maillard reactions.

Beverages↗
PubMed1990

Influence of coffee on fluoride metabolism in rats.

Concomitant intragastric administration of sodium fluoride and coffee resulted in a significantly higher (P less than 0.01) plasma fluoride level than intake of the same amount of fluoride with water. The same result was obtained when coffee was substituted with an equivalent amount of caffeine. Comparison of plasma fluoride levels by total area under the curve of plasma fluoride concentration versus time indicated an almost 2-fold difference. Although the mechanism(s) is not known, it appears that caffeine is responsible for the present observation. This finding could help explain the variations in the incidence of dental fluorosis among people living in optimally fluoridated communities.

Animals↗
PubMedDate not supplied

Effects of combined treatment with coffee cherry and whole-body hyperthermia on the growth of spontaneous mammary tumours in SHN mice.

Based on findings that free access in drinking water of the extract of coffee cherry (CC), the residue left after the removal of coffee beans, and whole-body hyperthermia (WBH) induced by far-infrared ray (FIR) can markedly inhibit the growth of spontaneous mammary tumours of SHN mice, the effects of the combined treatment with these agents were examined in this study. The significant inhibition of tumour growth by single treatment with either CC or WBH was not enhanced by their combination. Meanwhile, the body weight loss during WBH was significantly decreased by CC. Normal and preneoplastic growth of mammary glands and plasma component levels were affected little by either treatment. The findings confirmed the "normalization effects" of CC usually obtained with natural products and stress the need for prudence in the choice of any agent, natural or synthetic, to be applied simultaneously to increase the efficacy of WBH.

Animals↗
PubMedDate not supplied

Complementary study of boron absorption by coffee leaves using the neutron-capture-radiography method.

Young coffee plants were treated by putting a droplet of a solution containing 10B-enriched boron on some of their leaves. The rate of boron absorption by leaves (measured using neutron capture radiography) was found to be in the range of 1.9 to 5.3 nmol boron per h. This means that it requires several days for a coffee leaf to absorb most of the boron supplied by foliar spray in the usual agronomic treatments. Technically, the use of the method of neutron capture radiography has revealed to be quite sensitive and applicable to liquid micro-samples (a few microL in volume) even with the low-intensity neutron fluxes available in Costa Rica.

Absorption↗
PubMed1975

Coffee treat or trick?

The popularity of coffee is due not only to its pleasant taste and aroma but also to its physiologic and psychologic effects. These effects are caused mainly by the caffeine provided in the beverage. However, caffeine may have adverse effects as well, including stimulation of gastric acid secretion. A relationship between heavy coffee ingestion and myocardial infarction has not yet been established but it is a bothersome possibility.

Adult↗
PubMed1975

Collaborative study of a method for the determination of ochratoxin A in green coffee.

A method for the semiquantitative determination of ochratoxin A in green coffee has been studied collaboratively by 11 laboratories. The average recovery for the 7 samples spiked at 3 levels of ochratoxin A was 69.1%, ranging from 60.5 to 85.6%. This is comparable to other visual thin layer chromatographic methods of mycotoxin detection. The method has been adopted as official first action for the determination of ochratoxin A in green coffee beans.

Chromatography, Thin Layer↗
PubMed2002

Coffee stain technique.

Backgrounds prepared with coffee grounds and Conté dust produce many unexpected patterns. The technique adds interest to artwork and is equally good for a carefully prepared drawing as it is for a quick, casual sketch. A materials list is provided which includes a variety of surface choices. The article provides step-by-step directions for the preparation of an attractive coffee-stained background, gives detailed instructions describing how to transfer a sketch, offers tips for drawing with Conté and carbon pencils and tells how to apply highlights.

Art↗
PubMed1992

[Allergic rhinoconjunctivitis caused by the dust of green coffee beans].

In a 37-year-old worker employed in a coffee roastery who suffered from work-related rhinoconjunctivitis, allergologic investigations demonstrated sensitization to the dust of the green, unroasted coffee bean. This particular allergy is uncommon in Switzerland. The case is discussed and the literature on the subject is reviewed.

Adult↗