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PubMed1995

[Effects of smoking and coffee consumption on indicators of arterial pressure in 24-hour monitoring].

27 essential hypertensives were included in the study to evaluate the influence of cigarette smoking and coffee drinking on 24-hour blood pressure and its variability. The patients were untreated with antihypertensive drugs for at least 4 weeks. All the patients were coffee drinkers (4-5 cups a day) and cigarette smokers (during 25.2 +/- 7.4 years before study and about 10-20 times a day during last year). 24-hour ambulatory blood pressure monitoring (ABPM) was performed 3 times a week at one-day intervals. During the first and third ABPM the amount of coffee and cigarettes as well as schedule of both were equal, during the 2nd ABPM-smoking and coffee were prohibited. There were no significant differences between mean BP values and variability during the 1st and 3d ABPM. Variability of 24-h and daytime systolic blood pressure (SBP) was higher in the 1st--and 3d vs. 2nd ABPM. The 2nd ABPM revealed a significant SBP decrease at daytime (152.5 +/- 9.2 mm Hg vs. 147.2 +/- 8.9 mm Hg, p < 0.05) without changes in nighttime as well as in the whole 24-h period. Values of diastolic BP did not change. The results suggest that cigarette smoking and coffee drinking increase mean daytime and overall 24-hour SBP values and variability as well as heart rate, while diastolic BP is more stable.

Adult↗
PubMed1994

Is children's or parents' coffee or tea consumption associated with the risk for type 1 diabetes mellitus in children? Childhood Diabetes in Finland Study Group.

OBJECTIVE: The study was carried out to determine whether coffee or tea consumption by the child before diagnosis of diabetes or consumption by parents at the time of the child's conception or during pregnancy was associated with the risk for childhood type 1 diabetes. DESIGN: Case-control study. SETTING AND SUBJECTS: All diabetic children younger than 15 years, and diagnosed from September 1986 to the end of April 1989, were invited to participate. 600 newly diagnosed diabetic children and 536 randomly selected population-based children, and their parents took part in a nationwide study. RESULTS: The risk for type 1 diabetes was increased in the children who consumed at least 2 cups of coffee daily [odds ratio (OR) 1.94, 95% confidence interval (CI) 1.08-3.47], and in the children who consumed 1 cup of tea (OR 1.69, 95% CI 1.21-2.37) or at least 2 cups daily (OR 2.59, 95% CI 1.60-4.18) when adjusted for mother's education, child's age and child's sex. Parents' consumption of coffee or tea during conception of the child and mother's coffee consumption during pregnancy did not affect the risk for diabetes in the children. CONCLUSIONS: We observed an increased risk for type 1 diabetes in the children who consumed coffee or tea regularly.

Adolescent↗
PubMed1996

A prospective study of coffee drinking and suicide in women.

BACKGROUND: Among the many reported central nervous system effects of long-term caffeine use is improvement in mood. OBJECTIVE: To examine prospectively the relationship of coffee and caffeine intake to risk of death from suicide. METHODS: We conducted a 10-year follow-up study (1980 to 1990) in an ongoing cohort of 86 626 US female registered nurses aged 34 to 59 years in 1980, who were free of diagnosed coronary heart disease, stroke, or cancer. Information on coffee and caffeine intake was collected by a semiquantitative food frequency questionnaire in 1980. Deaths from suicide were determined by physician review of death certificates. RESULTS: Fifty-six cases of suicide occurred during 832 704 person-years of observation. Compared with non-drinkers of coffee, the age-adjusted relative risk of suicide in women who consumed two to three cups per day was 0.34 (95% confidence interval [CI, 0.17 to 0.68) and 0.42 (95% CI, 0.21 to 0.86) in women who consumed four or more cups per day (P for linear trend=.002). These findings remained essentially unchanged after adjusting for a broad range of potential confounding factors, including smoking habit, alcohol intake, medication use (diazepam and phenothiazine), history of comorbid disease (hypertension, hypercholesterolemia, or diabetes), marital status, and self-reported stress. A strong inverse relationship was similarly found for caffeine intake from all sources and risk of suicide. CONCLUSIONS: The data suggest a strong inverse association between coffee intake and risk of suicide. Whether regular intake of coffee or caffeine has clinically significant effects on the maintenance of affect or the prevention of depression merits further investigation in clinical trials and population-based prospective studies.

Adult↗
PubMed1997

Coffee and tea and the risk of recurrent colorectal adenomas.

Consumption of coffee has been associated with a reduction in the risk of cancer of the colon, and (less consistently) drinking tea has been associated with a reduction in the risk of rectal cancer. The effect of these beverages on the risk of colorectal adenomas, however, has not been well investigated. We used data from an adenoma prevention trial to investigate these associations. Patients with at least one recent large bowel adenoma were followed with colonoscopy 1 and 4 years after their qualifying examinations. Adenomas detected at the year 4 colonoscopy were used as end points. A food frequency questionnaire was administered at study entry and study completion; average intake over the study period was used to estimate the exposures of interest. There was no apparent association between the intake of regular coffee, decaffeinated coffee, or tea and the risk of recurrent colorectal adenomas. The relative risks and 95% confidence intervals per cup daily were 0.96 (0.87-1.05) for regular coffee, 0.97 (0.84-1.12) for decaffeinated coffee, and 1.02 (0.83-1.25) for tea. These negative findings were present both overall and for adenomas of the right and left large bowel.

Adenoma↗
PubMedDate not supplied

Effects of coffee cherry on the activation of splenic lymphocytes in mice.

We previously observed that the ingestion by mice of a hot water extract (CC) and the methanol-extracted and water-soluble fraction (CC-W) of coffee cherry, the residue remaining after the removal of coffee beans from the fruit, enhanced the differentiation of thymocytes and the activation of peripheral T-lymphocytes; and the anti-mammary tumour effects of coffee cherry extract was considered to be associated with this immunomodulation. To study further these effects, mitogen response and some immune parameters were examined in a high mammary tumour strain of SHN mice. While the T-lymphocyte response to concanavalin A was not significantly changed by either CC or CC-W, the lipopolysaccharide response was significantly enhanced by both treatments. The proportion of CD45R/B220+ (B) cells in the splenic lymphocytes was significantly increased by CC, and the percentage of activated (CD25+) cells in B-lymphocytes was increased by CC and CC-W. These data indicate that coffee cherry extract can enhance B-lymphocyte response, and suggest that this immunopotentiation contributes to the antitumourigenic role of coffee cherry.

Adjuvants, Immunologic↗
PubMed1997

Smoking, alcohol, coffee, and tea intake and incidence of cancer of the exocrine pancreas: the Iowa Women's Health Study.

To assess the relationship of smoking and coffee, tea, and alcohol intake to the risk of cancer of the exocrine pancreas, analyses were performed using data from a prospective cohort study of 33,976 postmenopausal Iowa women who responded to a mailed questionnaire in 1986 and were followed through 1994 for cancer incidence and total mortality. At baseline, information on cigarette smoking, consumption of tea, coffee, and alcoholic beverages, and other dietary and lifestyle factors was obtained. Age-adjusted relative risks of pancreatic cancer (n = 66 cases) showed a dose-response association with smoking. Those with fewer than 20 pack-years and those with 20 or more pack-years of smoking exposure were 1.14 (95% confidence interval, 0.53-2.45) and 1.92 (95% confidence interval, 1.12-2.30) times more likely, respectively, to develop pancreatic cancer than were nonsmokers. Current smokers were twice as likely as were nonsmokers to develop pancreatic cancer. Relative risks of pancreatic cancer increased with the amount of alcohol consumed (Ptrend = 0.11) after adjustment for age, smoking status, and pack-years of smoking. Relative risks of pancreatic cancer according to alcoholic beverage intake were as strong among never-smokers as they were in the total cohort. After the data were adjusted for age, smoking status, and pack-years of smoking, there was a statistically significant 2-fold (95% confidence interval, 1.08-4.30) elevated risk of pancreatic cancer for those who drank > 17.5 cups of coffee per week, compared to those who consumed < 7 cups/week; among never-smokers, the relative risks across coffee intake categories were still positive but were attenuated somewhat (P trend = 0.17). Tea intake was not related to cancer incidence. In summary, these findings provide evidence of an association of both alcoholic beverage and coffee consumption with pancreatic cancer incidence that is independent of age and cigarette smoking.

Age Factors↗
PubMed2004

Comprehensive multidimensional GC for the characterization of roasted coffee beans.

The present investigation is based on the separation of one of the most complex food matrices: the roasted coffee bean volatile fraction. Analysis of the two main species of coffee (Arabica/Robusta) was achieved through an effective and simple sampling procedure, headspace solid-phase microextraction (SPME), and the unprecedented resolving power of comprehensive gas chromatography (GC x GC). The combination of these two techniques proved to be a powerful tool for the extraction and separation of coffee volatiles. In fact, thousands of compounds that play various roles in the constitution of coffee aroma profile were resolved in the 2-D contour plot, each occupying a specific position pinpointed by two retention time coordinates. The potential use of this method for the assessment of coffee quality and the detection of commercial fraud is discussed. The potential of GC x GC for identification and classification of unknowns was also demonstrated, as the formation of characteristic patterns for structurally related compounds was observed in the bidimensional chromatogram. Moreover, reproducibility results were supported by the use of an autosampler for SPME applications that allowed any inaccuracy arising from manual handling to be avoided.

Journal Article↗
PubMed2006

Identification, characterization and utilization of EST-derived genic microsatellite markers for genome analyses of coffee and related species.

Genic microsatellites or EST-SSRs derived from expressed sequence tags (ESTs) are desired because these are inexpensive to develop, represent transcribed genes, and often a putative function can be assigned to them. In this study we investigated 2,553 coffee ESTs (461 from the public domain and 2,092 in-house generated ESTs) for identification and development of genic microsatellite markers. Of these, 2,458 ESTs (all >100 bp in size) were searched for SSRs using MISA--search module followed by stackPACK clustering that revealed a total of 425 microsatellites in 331 (13.5%) non-redundant ESTs/consensus sequences suggesting an approximate frequency of 1 SSR/2.16 kb of the analysed coffee transcriptome. Identified microsatellites mainly comprised of di-/tri-nucleotide repeats, of which repeat motifs AG and AAG were the most abundant. A total of 224 primer pairs could be designed from the non-redundant SSR-positive ESTs (excluding those with only mononucleotide repeats) for possible use as potential genic markers. Of this set, a total of 24 (10%) primer pairs were tested and 18 could be validated as usable markers. Sixteen of these markers revealed moderate to high polymorphism information content (PIC) across 23 genotypes of C. arabica and C. canephora, while 2 markers were found to be monomorphic. All the markers also showed robust cross-species amplifications across 14 Coffea and 4 Psilanthus species. The apparent broad cross-species/genera transferability was further confirmed by cloning and sequencing of the amplified alleles. Thus, the study provides an insight about the frequency and distribution of SSRs in coffee transcriptome, and also demonstrates the successful development of genic-SSRs. It is expected that the potential markers described here would add to the repertoire of DNA markers needed for genetic studies in cultivated coffee and also related taxa that constitute the important secondary genepool for coffee improvement.

Base Sequence↗
PubMed2006

Oleosin gene family of Coffea canephora: quantitative expression analysis of five oleosin genes in developing and germinating coffee grain.

Coffee grains have an oil content between 10% and 16%, with these values associated with Coffea canephora (robusta) and C. arabica (arabica), respectively. As the majority of the oil stored in oil seeds is contained in specific structures called oil bodies, we were interested in determining whether there are any differences in the expression of the main oil body proteins, the oleosins, between the robusta and arabica varieties. Here, we present the isolation, characterization and quantitative expression analysis of six cDNAs representing five genes of the coffee oleosin family (CcOLE-1 to CcOLE-5) and one gene of the steroleosin family (CcSTO-1). Each coffee oleosin cDNA encodes for the signature structure for oleosins, a long hydrophobic central sequence containing a proline KNOT motif. Sequence analysis also indicates that the C-terminal domain of CcOLE-1, CcOLE-3 and CcOLE-5 contain an 18-residue sequence typical of H-form oleosins. Quantitative RT-PCR showed that the transcripts of all five oleosins were predominantly expressed during grain maturation in robusta and arabica grain, with CcOLE-1 and CcOLE-2 being more highly expressed. While the relative expression levels of the five oleosins were similar for robusta and arabica, significant differences in the absolute levels of expression were found between the two species. Quantitative analysis of oleosin transcripts in germinating arabica grain generally showed that the levels of these transcripts were lower in the grain after drying, and then further decreased during germination, except for a small spike of expression for CcOLE-2 early in germination. In contrast, the levels of CcSTO-1 transcripts remained relatively constant during germination, in agreement with suggestions that this protein is actively involved in the process of oil body turnover. Finally, we discuss the implications of the coffee oleosin expression data presented relative to the predicted roles for the different coffee oleosins during development and germination.

Amino Acid Sequence↗
PubMed2006

Allantoin has a limited role as nitrogen source in cultured coffee cells.

In plants the ureides allantoin (ALN) and allantoic acid (ALA) are formed in purine metabolism, and in some legumes both compounds play an important role as nitrogen (N) sources. In coffee plants, ALN and ALA are catabolites of caffeine degradation. Caffeine is found throughout the coffee plant and in some parts this alkaloid can accumulate up to 4% dry basis. Therefore, caffeine degradation via ureides may make an important contribution to N metabolism of the plant. Using coffee cell suspension as a model we investigated the contribution of ALN as a source of N in coffee. ALN was incorporated in the liquid medium and after 20 d of cultivation, cell mass, NO(3), NH(4), amino acids, soluble proteins, ALN and caffeine were determined in the cells. The activity of glutamine synthetase was also studied. The results showed that despite being taken up by cells ALN does not contribute significantly as a source of N in coffee cells. Compared with mineral N sources, cells grown with ALN-N accumulated much less mass. The inclusion of ALN in the medium caused significant alterations in the content of some N compounds indicating a stress condition.

Allantoin↗
PubMed2000

Alpha-amylases of the coffee berry borer (Hypothenemus hampei) and their inhibition by two plant amylase inhibitors.

The adult coffee berry borer (Hypothenemus hampei Ferrari [Coleoptera: Scolytidae]), a major insect pest of coffee, has two major digestive alpha-amylases that can be separated by isoelectric focusing. The alpha-amylase activity has a broad pH optimum between 4.0 and 7.0. Using pH indicators, the pH of the midgut was determined to be between 4.5 and 5.2. At pH 5.0, the coffee berry borer alpha-amylase activity is inhibited substantially (80%) by relatively low levels of the amylase inhibitor (alphaAI-1) from the common bean, Phaseolus vulgaris L., and much less so by the amylase inhibitor from Amaranthus. We used an in-gel zymogram assay to demonstrate that seed extracts can be screened to find suitable inhibitors of amylases. The prospect of using the genes that encode these inhibitors to make coffee resistant to the coffee berry borer via genetic engineering is discussed.

Animals↗
PubMed2002

Incidence, level, and behavior of aflatoxins during coffee bean roasting and decaffeination.

Screening for aflatoxins (Afs), isolation and identification of Aspergillus flavus, and the effect of decaffeination and roasting on the level of contamination in coffee beans are studied. The percent frequency of A. flavus ranged between 4 and 80% in green coffee beans (GCB), whereas in ground roasted coffee beans (GRCB), it ranged between 1 and 71%. Aflatoxins were detected in 76.5 and 54.6% of the infected samples with averages of 4.28 and 2.85 microg/kg of GCB and GRCB, respectively. Roasting was demonstrated to lower the concentration of Afs in GCB. The Afs levels were reduced by approximately 42.2-55.9% depending on the type and temperature of roasting. The highest yields of Afs were detected in the decaffeinated green coffee beans (24.29 microg/kg) and roasted coffee beans (16.00 microg/kg). The growth of A. flavus in liquid medium containing 1 or 2% caffeine was reduced by 50%, and the level of aflatoxin in the medium was undetectable.

Aflatoxins↗
PubMed2003

Influence of roasting levels on ochratoxin a content in coffee.

Because of inconsistent and contradictory results from investigations concerning the influence of roasting process on the ochratoxin A content in coffee beans, a study was undertaken to assess the elimination of ochratoxin A during the roasting process. Four different green coffee samples, naturally contaminated with ochratoxin A, were submitted to different roasting conditions (light, medium, and dark) and analyzed for roasting parameters (weight loss, color change, density, and moisture content) and ochratoxin A content. The ochratoxin A content of green coffee was reduced by the roasting process; in particular, consistently high percentages of ochratoxin A reduction were found in the highest contaminated samples. This reduction was influenced by the severity of the thermal process and was generally related to the initial ochratoxin A content. Samples obtained with roasting parameters suitable for a typical Italian espresso coffee brew showed reductions of >90% in the ochratoxin A content, in both high and low contaminated samples. Moreover, the presence of off-flavors and visual defects was not found to be directly related to the ochratoxin A content in the green coffee samples.

Carcinogens↗
PubMed2004

Evolution of robusta green coffee redox enzymatic activities with maturation.

Oxidation reactions in coffee involve redox-sensitive polyphenols and appear to control the fragmentation of coffee storage proteins both in solution and during roasting. Coffee-specific nitrogenous flavor precursors may derive from this process. Accordingly, data converge to suggest that the redox status of the green bean before roasting might control the development of subsequent redox reactions during roasting. Consequently, we decided to identify biological events that may trigger or prevent oxidation during maturation of the coffee cherry and set the final redox status of the green bean. In a previous study, we observed that the sensitivity of green coffee to oxidative processes decreased along maturation. By using the very same samples originating from open-pollinated Robusta clones, we followed the activity of three essential redox enzymes: catalase (CAT), peroxidase (POD) and polyphenoloxidase (PPO). While CAT and POD activities increased with maturation, PPO activities decreased. Thanks to the identification of an atypical immature subclass, it appeared that CAT might be an essential factor in setting the final redox status of the green bean before the roasting event.

Catalase↗
PubMed2004

Characterization and estimation of proanthocyanidins and other phenolics in coffee pulp (Coffea arabica) by thiolysis-high-performance liquid chromatography.

Fresh and 3-day-old coffee pulp of the Arabica variety were analyzed for polyphenol composition followed by characterization by two different methods. The first method consisted in subjecting coffee pulp powder to direct thiolysis. For the second method, coffee pulp was subjected to successive solvent extractions, followed by thiolysis. Quantification of phenolic compounds was then achieved by high-performance liquid chromatography (HPLC) analysis of thiolysis products. Four major classes of polyphenols were identified: flavan-3-ols (monomers and procyanidins), hydroxycinnamic acids, flavonols, and anthocyanidins. Differences in concentration of procyanidins were observed between fresh and 3-day-old coffee pulp. Constitutive units were mainly epicatechin, representing more than 90% of the proanthocyanidin units, with average degrees of polymerization in the range of 3.8-9.1. Monomer to hexamer units of flavan-3-ols from fresh coffee pulp were separated by normal-phase HPLC. Molecular size of oligomeric proanthocyanidins was obtained by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Results obtained confirm the presence of oligomers of the flavan-3-ol (-)-epicatechin.

Chromatography, High Pressure Liquid↗
PubMed2005

Assessing the antioxidant activity of melanoidins from coffee brews by different antioxidant methods.

Antioxidant activity of instant coffees produced from the same green coffee beans roasted at three different degrees was analyzed. Coffee melanoidins were obtained by ultrafiltration (10 kDa cutoff) and subsequent diafiltration. Pure melanoidins were isolated from melanoidins after overnight incubation in 2 M NaCl and then ultrafiltered. Filtrates, corresponding to the low molecular weight (LMW) fraction noncovalently linked to the melanoidin skeleton, were also preserved. Antioxidant activity of coffee brews (CB), melanoidins (M), pure melanoidins (PM), and bounded melanoidin compounds (BMC) were tested using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing power (FRAP) methods. The correlation between the different methods was studied. The higher contribution of melanoidins to the total antioxidant activity of coffees was shown to be caused by the LMW compounds linked noncovalently to the melanoidin skeleton, as data from BMC confirmed. CB, M, and BMC fractions exert the highest antioxidant activity in aqueous media, whereas PM was not dependent on the reaction media. The highest correlation was found between DPPH and FRAP methods.

Antioxidants↗
PubMed2001

Coffee and coronary heart disease.

BACKGROUND: The role of coffee consumption in the onset of myocardial infarction remains uncertain. A review of published reports showed that although cohort data suggest very little excess risk of coronary heart disease among habitual coffee drinkers, case-control data suggest an excess risk of the order of 60% for people drinking five or more cups per day. METHODS: We obtained as much information as possible on the lifestyle and habits, including coffee consumption, of people admitted with chest pain to the Coronary Care Unit at the Royal Perth Hospital, Australia. A questionnaire was given to them by the attending nursing staff. Details were recorded by the patient, often with help from the nursing staff. A similar questionnaire was completed by patients attending the Cardiology Outpatient Clinic. RESULTS: One of the outstanding differences between the 182 patients with myocardial infarction or unstable angina and 185 patients with chronic stable coronary heart disease who filled in forms while waiting in the Cardiology Outpatient Clinic was that more people with acute coronary syndromes were drinking in excess of five cups of coffee per day (18 vs 7.5%; P = 0.003). In logistic regression analysis adjusted for age, smoking status (past and current), hypertension, dyslipidaemia and diabetes, the odds ratio was 2.51 (95% CI 1.43,4.43; P = 0.021). CONCLUSION: The present case-control study provides evidence for an increased risk of myocardial infarction or unstable angina among individuals drinking more than five cups of coffee per day.

Journal Article↗
PubMed2005

Biological control of the coffee berry borer Hypothenemus hampei (Coleoptera: Curculionidae) by Phymastichus coffea (Hymenoptera: Eulophidae) in Colombia.

The potential of the eulophid parasitoid Phymastichus coffea LaSalle to control coffee berry borer Hypothenemus hampei (Ferrari) populations under field conditions in Colombia was evaluated. Parasitoid adults were released one, five and nine days after artificial infestations of 90-, 150- and 210-day-old coffee berries with H. hampei females. The position of the beetle inside the berry and the parasitism levels were assessed ten days after each P. coffea release. Parasitism of H. hampei by P. coffea was significantly affected by the age of the berries at the time of infestation, and by the position of the beetle inside the berries. Highest levels of parasitism were recorded in 150-day-old berries (75-85%) and in 90-day-old berries (75%) when P. coffea were released one day after the artificial infestation with H. hampei. In 150-day-old berries, highest levels of parasitism were recorded for H. hampei found in the outer layer of the endosperm followed by beetles penetrating the exocarp. Increasing the time of P. coffea releases after the artificial infestations with H. hampei led to decreased levels of parasitism in beetles attacking 90- and 150-day-old coffee berries. Low levels of parasitism were recorded in H. hampei females infesting older coffee berries because most of the beetles had already constructed galleries deep in the endosperm of the berries, i.e. out of reach of the parasitoid. The potential of P. coffea for biological control of coffee berry borer in Colombia is discussed.

Animals↗