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Inhibition of mutagenicity of a model nitrosation reaction by naturally occurring phenolics, coffee and tea.

Several plant phenolics, one instant coffee, one instant decaffeinated coffee, one roasted coffee, one Japanese tea, one black Indian tea, and one Chinese tea were examined for their inhibitory properties on mutagenicity resulting from the nitrosation of methylurea. Mutagenicity was estimated as the number of his+ revertants per survivor of Salmonella typhimurium TA1535 which was exposed in suspension to the nitrosation mixtures and the modulating agents for 20 min. Tannic acid, gallic acid and chlorogenic acid suppressed the mutagenicity of the model nitrosation system at concentrations similar to or even lower than ascorbic acid. The three tested coffees and three tested teas exerted an inhibitory effect on the mutagenicity of the test system at doses at which they are consumed.

Chlorogenic Acid↗

Effect of a lipid-rich fraction from boiled coffee on serum cholesterol.

Scandinavian-style boiled coffee, which raises serum cholesterol, was found to contain more lipid material than drip filter coffee, which does not. Ten volunteers consumed a lipid-enriched fraction from boiled coffee for six weeks: the supplement provided 77 g of water, 1.3 g of lipid, and 1.6 g of other solids per day. Serum cholesterol rose in every subject; the mean rise was 0.74 mmol/l after three weeks (range -0.09 to 1.48 mmol/l) and 1.06 SD 0.37 mmol/l or 23% after six weeks (range 0.48 to 1.52 mmol/l). The increase was mainly due to low-density-lipoprotein cholesterol, which rose by 29%, but very-low-density lipoprotein cholesterol was also raised, as evidenced by a 55% rise in triglycerides. High-density-lipoprotein cholesterol was unchanged. After supplementation had ended, lipid levels returned to baseline. Boiled coffee thus contains a lipid that powerfully raises serum cholesterol.

Adult↗

Clastogenic agents in the urine of coffee drinkers and cigarette smokers.

Organic material from the urine of smokers, coffee drinkers, and controls was extracted and separated into 3 fractions of differing hydrophobicity using preparative reversed-phase high-pressure liquid chromatography. Fractions were assayed for clastogenic activity using Chinese hamster ovary cells. Smoking, coffee drinking, or both habits together resulted in a substantial increase in the genotoxicity of organic material in all 3 fractions. The clastogenicity of fractions 1 and 2 (the two most hydrophilic) was abolished by the addition of either catalase or superoxide dismutase to the Chinese hamster ovary cell system, suggesting the involvement of active oxygen species in the clastogenic response. Clastogenicity of fraction 3, however, was resistant to the action of catalase and superoxide dismutase. Fractions were tested for their ability to generate hydrogen peroxide in vitro during a 10-min incubation at elevated pH. Fractions 2 and 3, but not fraction 1 from smokers, coffee drinkers, or those with both habits generated significantly more hydrogen peroxide at high pH than did the corresponding fractions from control subjects. For fractions 2 and 3 but not 1, the ability of a sample to generate hydrogen peroxide at high pH was positively correlated with its ability to generate chromosome aberrations at neutral pH in tissue culture. The data indicate that both coffee drinking and cigarette smoking result in the appearance of clastogenic materials in urine, and suggest that such clastogenic agents may produce chromosome aberrations via the production of active oxygen species.

Animals↗

Mutagenicity of instant coffee and its interaction with dimethylnitrosamine in the micronucleus test.

The mutagenicity of instant coffee and its interaction with dimethylnitrosamine (DMN) were examined in mice using the micronucleus test. Although neither a single nor multiple administration of instant coffee by gavage induced a significant rise in micronucleated cells over the dose range tested (100-2500 mg/kg), there was a tendency for the number of micronucleated cells to increase in a dose-related fashion. When coffee was administered with DMN, the difference in the frequency of micronucleated cells was small in comparison to a single treatment with DMN alone, thus indicating a lack of synergism between coffee and DMN.

Animals↗

Regular or decaffeinated coffee and subsequent human aggressive behavior.

A new methodology was used to study the effects of coffee on human aggressive behavior in a laboratory situation. Aggressive responding was elicited by subtracting money from the research subjects, an action which was attributed to a fictitious person. Regular coffee compared to decaffeinated coffee produced decreases in aggressive responses, but increased nonaggressive monetary reinforced responding. Thus, the suppressing effect of regular coffee on aggressive responding was not due to a nonspecific depressant action.

Adolescent↗

Inhibitory effects of coffee on the genotoxicity of carcinogens in mice.

The mouse bone marrow micronucleus test was carried out to evaluate the possible inhibitory effects of 3 doses (125, 250 and 500 mg/kg) of standard instant coffee on the in vivo genotoxicity of 7,12-dimethylbenz[a]anthracene (DMBA), benzo[a]pyrene (BP), aflatoxin B1 (AFB1) and urethane (UR). Coffee was orally administered twice, 2 and 20 h before the carcinogens were injected intraperitoneally. From the results obtained, it was evident that the administration of 250 and 500 mg coffee/kg body weight could significantly inhibit the in vivo genotoxicity of these carcinogens. A linear dose response was observed for the inhibitory effect of coffee. Furthermore, inhibition of genotoxicity by coffee was observed in bone marrow cells which were sampled at 6-h intervals (48, 54, 60, 66 and 72 h) from the time of peak induction of micronuclei by DMBA.

9,10-Dimethyl-1,2-benzanthracene↗

Coffee drinking and bladder cancer.

A case-control study was conducted in the Main Hospital of Torino on 512 men and 55 women with bladder cancer, and 596 male and 202 female controls. The association with coffee drinking was investigated. In males, the odds ratios for current consumption were 0.8, 1.0, 1.2 and 0.8 for 1, 2, 3 and 4+ cups of coffee per day, respectively (adjusted for age, smoking and occupations at risk). The odds ratios for a daily consumption of 1, 2, 3 and 4+ cups 10 years before interview were 1.2, 1.5, 1.1 and 1.1, respectively. None of the estimates were statistically significant. These results are consistent with most of the previous findings. In males increased odds ratios were observed in non-smokers, with a dose-response relationship both for current and past coffee drinking habits. The association between bladder cancer and coffee consumption is unclear but it seems that smoking could play a role as an effect modifier.

Adult↗

Event time-series relationship between cigarette smoking and coffee drinking.

Eight subjects resided in a programmed laboratory environment for seven to twelve successive days during which time cigarettes and coffee were freely available. An event time-series analysis based upon instances in time of each substance's use revealed a relationship between cigarette smoking and coffee drinking: a coffee-drinking event tended to occur late in the inter-cigarette interval, and a cigarette-smoking event was most probable during the twenty minutes immediately following a coffee-drinking event.

Coffee↗

A simple method to measure effective catalase activities: optimization, validation, and application in green coffee.

Oxidative metabolism in coffee cherries during maturation appears to be regulated by the timely expression of redox enzymes such as catalase (CAT), peroxidase (POD), and polyphenoloxidase (PPO). Among these enzymes, CAT is suspected to contribute significantly in setting the redox status of the healthy cherry and the processed bean. The initial redox status of the green bean might further control the nature and dynamics of reactions induced by roasting and eventually quality aspects of the end product. In this respect, Arabica (Coffea arabica) and Robusta (Coffea canephora) typically differ by their cup coffee flavor profiles. We developed an assay that allowed us to screen numerous green coffee samples for effective CAT activities. The proposed assay, which monitors CAT activities by online oxygen sensing in green coffee crude suspensions incubated with H2O2, seeks to integrate potential effects of endogenous inhibitors and activators. After optimization and validation of the assay, 23 Arabicas, 23 Robustas, and 8 Arabustas were analyzed. Nearly all Arabicas (22 of 23) harbored high CAT activity levels, whereas all Robustas harbored low ones. Arabustas performed like Arabicas of the lower CAT activity range. The traditional spectrophotometric assay did not reveal these specificities. Because of its simplicity, our assay might be valuable for assessing effective CAT activities in various plant tissues.

Catalase↗

Maternal coffee and alcohol consumption during pregnancy, parental smoking and risk of childhood acute leukaemia.

INTRODUCTION: We investigated the role of maternal alcohol and coffee drinking and parental smoking on the risk of childhood acute leukemia in a multicenter case-control study. METHODS: The study included 280 incident cases and 288 hospitalized controls, frequency matched with the cases by age, gender and center. Data collection was completed by face-to-face standardized interviews of the case and control mothers. RESULTS: An association with maternal alcohol consumption during pregnancy was observed with acute lymphoid leukemia (ALL) (OR=2.0 [1.4-3.0]) and acute non-lymphoid leukemia (ANLL) (OR=2.6 [1.2-5.8]). Maternal coffee consumption during pregnancy was associated with childhood acute leukemia, ORs increasing in ALL with coffee consumption (OR=1.1 [0.7-1.8], OR=2.4 [1.3-4.7] and OR=3.1 [1.0-9.5], respectively, for < or =3, 4-8 and >8 cups/day). No association with maternal smoking during pregnancy or parental smoking before or after the index child's birth was observed. DISCUSSION: Our results suggest an association with maternal alcohol and coffee drinking during pregnancy and call for further investigations. Besides, the present study does not support the hypothesis of an increase in the risk of childhood leukemia related to parental smoking.

Adolescent↗

Modelling of effects of water activity and temperature on germination and growth of ochratoxigenic isolates of Aspergillus ochraceus on a green coffee-based medium.

Influence of water activity (0.75-0.99 a(w)) and temperature (10, 20 and 30 degrees C) on germination and mycelial growth on green coffee extract agar medium of three ochratoxigenic isolates of Aspergillus ochraceus was studied. Optimal conditions for germination and growth were observed at 0.95-0.99 a(w) and 20-30 degrees C for the three isolates. Minimum a(w) level for germination was 0.80, and 0.85 for mycelial growth. At marginal a(w) and temperature levels assayed, the lag phases prior to germination increased and the growth rates showed a significant decrease in comparison with the optimal conditions. Data were modelled by a multiple linear regression (MLR) and response surface models were obtained. Germination and growth of A. ochraceus in green coffee beans could be prevented or at least inhibited to some extent by minimising the time that coffee beans are exposed to temperature and humidity conditions near to the optimum during processing and storage. This could be an empirical approach to predict the effects of water activity and temperature conditions on the development of ochratoxigenic isolates of A. ochraceus during handling and storage of green coffee.

Aspergillus ochraceus↗

Breakfast cereal and caffeinated coffee: effects on working memory, attention, mood, and cardiovascular function.

This study examined the effects of breakfast cereal and caffeinated coffee on working memory, attention, mood, and cardiovascular function. One hundred and forty-four volunteers (72 male, 72 female, mean age 21 years) were assigned to one of the groups formed by combining breakfast (cereal versus no breakfast) and caffeine (caffeinated versus decaffeinated coffee) conditions. The volunteers completed a baseline session between 0800 and 0845 h. The breakfast/caffeine administration took place between 0845 and 0915 h. They then completed another test session (starting at 0945) and had a coffee break at 1045, followed by a final session starting at 1145. The results showed that those who consumed breakfast cereal had a more positive mood at the start of the test sessions, performed better on a spatial memory task, and felt calmer at the end of the test session than those in the no breakfast condition. Ingestion of caffeine had no effect on initial mood or working memory, but it did improve encoding of new information and counteracted the fatigue that developed over the test session. Caffeine increased blood pressure and pulse rate, whereas breakfast cereal consumption only had an effect on pulse. Overall, these results confirm previous findings on the effects of breakfast and caffeine, and demonstrate distinct profiles for two common examples of early-morning food and drink, breakfast cereal and caffeinated coffee.

Adult↗

Studies on aluminium leaching from cookware in tea and coffee and estimation of aluminium content in toothpaste, baking powder and paan masala.

Studies were conducted in order to assess the level of aluminium (Al) in samples of Indian tea, coffee, toothpaste, paan masala (mouth freshener) and baking powder. Leaching of Al from cookware while preparing tea and coffee was also studied. Experiments were also conducted to study the sequential leaching of Al from cookware by preparing tea and coffee in the presence of standard size Al sheets (coupons). A small amount of Al was found to have leached from coupons during preparation of tea. Tea leaves, were found to be a rich source of Al and a maximum of 2.2% Al is extracted in tea infusions. Coffee powder on the other hand was not found to be a rich source of Al. Baking powder was found to be a rich source of Al and 1 kg of cake prepared with 1-3 teaspoon of baking powder may contain 2-12.7 mg of Al in each serving (25 g). Toothpaste also contains a significant quantity of Al, more so, when packed in Al tubes. Ingestion pattern of Al from these items by humans is also discussed.

Alum Compounds↗

Use of herbal products, coffee or black tea, and over-the-counter medications as self-treatments among adults with asthma.

BACKGROUND: There are few data on the use of alternative therapies in adult asthma and their impact on health outcomes. OBJECTIVE: The objective of this study was to study the prevalence and morbidity of asthma self-treatment with herbs, coffee or black tea, and over-the-counter (OTC) medications containing ephedrine or epinephrine. METHODS: We carried out a cross-sectional analysis of interview data for 601 adults with asthma recruited from a random sample of pulmonary and allergy specialists. We estimated the 12-month prevalence of reported use of herbal products, coffee or black tea, or OTC products to self-treat asthma and their association with emergency department visits and hospitalization. RESULTS: Herbal asthma self-treatment was reported by 46 (8%; 95% confidence interval [CI] 6% to 10%); coffee or black tea self-treatment by 36 (6%; 95% CI 4% to 8%), epinephrine or ephedrine OTC use by 36 (6%; 95% CI 4% to 8%), and any of the three practices by 98 subjects (16%; 95% CI 13% to 19%). Adjusting for demographic and illness covariates, herbal use (odds ratio [OR] 2.5; 95% CI 1.1 to 5.6) and coffee or black tea use (OR 3.1; 95% CI 1.2 to 7.8) were associated with asthma hospitalization; OTC use was not (OR 0.8; 95% CI 0.3 to 2.5). CONCLUSIONS: Even among adults with access to specialty care for asthma, self-treatment with nonprescription products was common and was associated with increased risk of reported hospitalization. This association does not appear to be accounted for by illness severity or other disease covariates. It may reflect delay in utilization of more efficacious treatments.

Adolescent↗

Coffee consumption and risk of type 2 diabetes mellitus.

Coffee is a major source of caffeine, which has been shown to acutely reduce sensitivity to insulin, but also has potentially beneficial effects. We prospectively investigated the association between coffee consumption and risk of clinical type 2 diabetes in a population-based cohort of 17111 Dutch men and women aged 30-60 years. During 125774 person years of follow-up, 306 new cases of type 2 diabetes were reported. After adjustment for potential confounders, individuals who drank at least seven cups of coffee a day were 0.50 (95% CI 0.35-0.72, p=0.0002) times as likely as those who drank two cups or fewer a day to develop type 2 diabetes. Coffee consumption was associated with a substantially lower risk of clinical type 2 diabetes.

Adult↗

[Severe anaphylactic shock with heart arrest caused by coffee and gum arabic, potentiated by beta-blocking eyedrops].

The case of a male patient who experienced four allergic accidents after drinking coffee is reported. Two serious anaphylactic reactions with cardiac arrest occurred after a continuous treatment with beta-blocking eye drops (timolol) was prescribed. Dual sensitivation to coffee and to the gum arabic coating roasted coffee beans was demonstrated by skin prick tests and by human basophil degranulation tests. Occupational allergy to green coffee has been widely described, but food sensitization to these two allergens has not yet been reported. This case also draws attention to the risk, inherent in beta-blockers, of immuno-allergic reactions. These drugs produce a loss of compensatory cardiovascular mechanisms and make those who take them resistant to the conventional treatment of anaphylactic shocks, which explains the serious accidents that occurred in this patient. The authors stress the usefulness of a thorough investigation for food allergy to a rare allergen in patients with idiopathic anaphylaxis.

Aged↗

Modulation of the stress response by coffee: an in vivo microdialysis study of hippocampal serotonin and dopamine levels in rat.

We studied whether coffee and its components (caffeine and chlorogenic acid) have stress-relaxing effects. In vivo brain microdialysis was used to characterize the effects of coffee, stress, and their interaction on the serotonergic and dopaminergic systems in the rat hippocampus. Restraint stress for 100 min caused a marked increase in dopamine and serotonin (5-HT) levels in the hippocampus, and then, 100 min resting (freely-moving) time reduced them to basal levels. Pretreatment with 33 mg/kg coffee or 1.7 mg/kg caffeine reduced the second restraint-induced increase in the neurotransmitters, especially 5-HT, but neither saline nor 1.7 mg/kg chlorogenic acid did. These results suggest that coffee contributes to the reduction of restraint-induced stress and that these effects could be due to caffeine. Possible mechanisms of the effects are considered.

Animals↗

Caffeinated coffee and tea intake and its relationship to cigarette smoking: an analysis of the Second National Health and Nutrition Examination Survey (NHANES II).

Recent studies have shown that smokers' intake of caffeine is higher than nonsmokers. This investigation evaluated the relationships between smoking status and self-reported caffeine intake from both coffee and tea. Subjects were adults who participated in the Second National Health and Nutrition Examination Survey (NHANES II). Results indicated that subjects who ingested caffeine from tea were more likely to be female, less educated, younger, non-Caucasian, and lighter drinkers. In contrast, those who ingested caffeine from coffee were more likely to be older, Caucasian, heavier drinkers, and have higher incomes. Smokers were not more likely to drink caffeinated tea. In contrast, smokers were much more likely to drink caffeinated coffee, and a dose-response relationship between caffeine from coffee and smoking intake was observed. These results clarify the relationship between smoking and caffeine intake. Implications for intervention efforts are discussed.

Adolescent↗