Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| caffeine: its direct and indirect influence on reproduction. | caffeine constitutes the active drug principle in a number of commonly consumed beverages. among north american adults, it holds the distinction as being probably the most widely utilized psychotropic drug. the compound is most often consumed in the form of coffee, which is derived from the bean of the tropical tree coffea arabica or coffea robusta. the unique pharmacologic and physiologic properties of caffeine have led to extensive research efforts, especially in the area of mutagenically and ... | 1977 | 197235 |
| [studies on coffee and coffee substitutes. xix. dependence of the quantity of a highly polymeric galactomannan on the degree of extraction coffee-extracts (author's transl)]. | in extracts of columbia arabica coffee the content of galactomannan precipitable with alcaline copper solution decreases slowly up to an extraction yield of 43.6%; it decreases somewhat more rapidly with higher extraction yields. an extract of angola robusta coffee showed opposite behaviour. in this case the content of galactomannan increased with the extraction yield, although not evenly. calculated on the basis of roasted coffee solids the extract of the arabica coffee had a rather limited ran ... | 1977 | 878640 |
| a study of the lipid content of coffea arabica l. seeds. | 1975 | 1161800 | |
| [investigation on coffee and coffee-substitutes. xvii. behaviour of polysaccharide-complexes of robusta-coffee during roasting]. | two varieties of coffea robusta of light, medium and dark roasting degree were investigated. the results were similar to those which were published earlier concerning coffea arabica. one part of the mannane and galactane is destroyed. another part, which exists originally as a constituent of the holocellulose, is made water soluble. of this part, the mannane is found in the complex of water soluble polysaccharides, the galactane in the complex of galactoarabane. | 1975 | 1229720 |
| the influence of roasting procedure on the formation of mutagenic compounds in coffee. | mutagenic products can be formed during the processing of food and especially as a result of heat treatment. direct acting mutagenic activity was found in extracts of instant coffee and roasted coffee beans using salmonella typhimurium ta100 in vitro. the mutagenic activities of the four pure coffee varieties examined (coffea arabica santos, coffea arabica columbia, coffee robusta indonesia, coffee robusta camerun) were within the same range. twenty milligrams per plate freeze-dried powder prepa ... | 1985 | 3891559 |
| coffea arabica. | 1981 | 6941089 | |
| [epidemiology of anthracnosis and eye spot disease, conclusions for its prognosis of occurrence and its control in the republic of cuba]. | the course of attacks by anthracnosis and by the eye spot disease on branches, leaves, and fruits of coffea arabica l. were investigated in cuba. the daily precipitation and the shading are most influential for both diseases. there are marked differences in the attacks between the rainy season (highest attacks) and dry season (decreased attacks). lack of shading increases the susceptibility of the plants to the eye spot disease. under the conditions in cuba, unshaded plantations exhibited an inc ... | 1982 | 7126133 |
| tobacco, cocoa, coffee, and ragweed: cross-reacting allergens that activate factor-xii-dependent pathways. | a glycoprotein antigen has been isolated from cured tobacco leaves (tgp-l) nicotiana tabacum) and from cigarette smoke condensate (tgp-csc) to which approximately one-third of human volunteers, smokers and non-smokers, exhibit immediate cutaneous hypersensitivity. tgp-l and tgp-csc contain polyphenol haptens that activate the factor xii (hageman factor) dependent pathways of coagulation, fibrinolysis, and kinin generation in normal human plasma. the purpose of this communication is to describe t ... | 1981 | 7295998 |
| antifungal properties of 1,3,7-trimethylxanthine, isolated from coffea arabica. | 1980 | 7422010 | |
| a placebo-controlled parallel study of the effect of two types of coffee oil on serum lipids and transaminases: identification of chemical substances involved in the cholesterol-raising effect of coffee. | in a randomized double-blind parallel study in 36 subjects the effect on serum cholesterol of a daily dose of 2 g lipid extracted from green arabica and robusta coffee beans was studied. arabica oil elevated serum total cholesterol by 1.1 mmol/l (95% ci for the difference from placebo: 0.41, 1.73 mmol/l); the effect of robusta oil (+0.5 mmol/l) was not statistically significant (95% ci: -0.01, 0.92 mmol/l). arabica oil also raised plasma triglycerides by 0.8 mmol/l (95% ci: 0.26, 1.25 mmol/l). t ... | 1995 | 7762531 |
| diterpene composition of oils from arabica and robusta coffee beans and their effects on serum lipids in man. | the cholesterol-raising effect of boiled coffee is caused by diterpenes from coffee oil. in order to identify the diterpene responsible, we analysed the diterpene composition of oils from arabica (coffea arabica) and robusta (coffea canephora robusta) beans and their effects on serum lipids and thyroid function. design, subjects, and intervention: during the first 3-week period of a randomized, cross-over trial, 11 healthy, normolipaemic volunteers received per day either 2 g of coffee oil (n = ... | 1995 | 7782725 |
| a cdna encoding a metallothionein i-like protein from coffee leaves (coffea arabica). | 1995 | 7870830 | |
| investigation of the effect of coffee lipids on serum cholesterol in hamsters. | the effect of coffee total lipids (ctl), coffee non-saponifiable matter (nsm) and coffee diterpene alcohols (dta) extracted from coffea arabica beans on serum cholesterol in adult male syrian hamsters was examined. the animals were fed either a commercial laboratory chow diet (study 1), containing 5% fat and low in saturated fat (1.46 g/100 g diet) and cholesterol (0.03 g/100 g diet) or a semi-synthetic diet (study 2) set in gelatine, containing 10% fat and high in saturated fat (4 g/100 g diet) ... | 1995 | 7896229 |
| potential sources of sugar for the phlebotomine sandfly lutzomyia youngi (diptera: psychodidae) in a colombian coffee plantation. | sugar-deprived lutzomyia youngi were exposed to each of the five most numerous plant species in a colombian coffee plantation for 24 h and then tested for the presence of fructose by the cold anthrone assay. many flies exposed to coffee (coffea arabica) (up to 55% in an individual test) and guamo (inga edulis) (up to 28.0%) gave positive results. although some flies also took sugar from red-flowered balsam (impatiens balsamina) and bamboo (bambusa angustifolia), none of the insects exposed to pl ... | 1994 | 7979645 |
| analysis of free amino acids in green coffee beans. i. determination of amino acids after precolumn derivatization using 9-fluorenylmethylchloroformate. | for the determination of free amino acids in green coffee beans, 9-fluorenylmethylchloroformate was applied successfully as the precolumn derivatization agent. the separation of the 27 free amino acids of green coffee as yet identified or quantitatively determined is almost complete. the paper describes in detail the conditions of extraction, derivatization and resolution and presents reproducible data of standard curves and of quantitative results. it has been demonstrated that by applying the ... | 1994 | 8067059 |
| lipid content and composition of coffee brews prepared by different methods. | the lipid content and composition of boiled, filtered, dripped, turkish and espresso coffees prepared from roasted beans of coffea arabica and coffea robusta, and of coffees prepared from different brands of instant coffee were examined. the lipid content varied with the method of preparation. while coffee brews filtered through filter paper contained less than 7 mg lipids, those prepared by boiling without filtering and espresso coffee reached 60-160 mg lipids/150-ml cup. coffee brew filtered t ... | 1993 | 8477916 |
| semiquantitative evaluation of dermal exposure to granulated insecticides in coffee (coffea arabica l.) crop and efficiency of individual protective equipment. | 1996 | 8875843 | |
| chilling stress leads to increased cell membrane rigidity in roots of coffee (coffea arabica l.) seedlings. | tropical and sub-tropical higher plant species show marked growth inhibition when exposed to chilling temperatures. in root tip segments of coffee seedlings which were subjected for 6 days to temperatures of 10, 15, 20 and 25 degrees c, in darkness, we have detected an increased amount of malondialdehyde formed in the 10 degrees c treatment, accompanied by higher electrolyte leakage. the electron paramagnetic resonance (epr) technique and the fatty acid spin probes 5-, 12- and 16-doxylstearic ac ... | 1997 | 9030214 |
| [use of a coffea arabica tosta extract for the prevention and therapy of polyfactorial infectious diseases in newborn calves]. | two studies have been carried out to evaluate the prophylactic and therapeutical effect of a 30%-extract from the coffee-bean seeds coffeae arabicae on infectious diseases in newborn calves. 1. within a large cattle-herd, which endemically showed a high proportion of infections within the gastroenteric and/or respiratory systems in calves, a randomised placebo-controlled double-blind study has been done. 50 newborn calves were given a subcutaneous injection of 10 ml coffea-preparation 30% on fir ... | 1996 | 9035968 |
| analysis of free amino acids in green coffee beans. ii. changes of the amino acid content in arabica coffees in connection with post-harvest model treatment. | to investigate amino acid changes in green coffee beans in the post-harvest period, amino acid concentrations were determined in green beans and after modelled drying, fermentation and storage. after the drying at alternating temperatures up to maximally 40 degrees c, considerable changes in the concentrations of individual amino acids were identified. at the beginning of the storage period, significant changes in concentration were found to a minor extent. under the condition of drying, it was ... | 1996 | 9123976 |
| lipid analysis of coffea arabica linn. beans and their possible hypercholesterolemic effects. | lipid composition of green coffea arabica beans is reported with special emphasis on fatty acid composition. triacylglycerols were found to be the major lipid constituents of the coffee oil along with sterol esters, sterols/triterpene alcohol, hydrocarbons and the hydrolyzed products of triacylglycerols as the minor components. fatty acid composition of total oil, neutral lipids, polar lipids and pure triacylglycerols showed the presence of fatty acids of c14, c16, c18, and c20 carbon chains. pa ... | 1997 | 9135777 |
| coffea arabica l., a new host plant for acetobacter diazotrophicus, and isolation of other nitrogen-fixing acetobacteria. | acetobacter diazotrophicus was isolated from coffee plant tissues and from rhizosphere soils. isolation frequencies ranged from 15 to 40% and were dependent on soil ph. attempts to isolate this bacterial species from coffee fruit, from inside vesicular-arbuscular mycorrhizal fungi spores, or from mealybugs (planococcus citri) associated with coffee plants were not successful. other acid-producing diazotrophic bacteria were recovered with frequencies of 20% from the coffee rhizosphere. these n2-f ... | 1997 | 9293018 |
| two different conductances contribute to the anion currents in coffea arabica protoplasts. | the anion conductance of the plasma membrane of coffea arabica protoplasts was isolated and characterized using the whole-cell patch clamp technique. voltage pulse protocols revealed two components: a voltage-gated conductance (gs) and a voltage-independent one (gl). gs is activated upon depolarization (e-fold activation every +36 mv) with time constants of 1 sec and 5 sec at all potentials. gl and gs also differ by their kinetic and biophysical properties. in bi-ionic conditions the current ass ... | 1997 | 9309213 |
| biochemistry and toxicology of the diterpenoid glycoside atractyloside. | atractyloside (atr) is a diterpenoid glycoside that occurs naturally in plants (many of which are used in ethnomedicines) found in europe, africa, south america, asia and the far east. it is also present in animal grazing forage. atr (and its analogues) may be present at levels as high as 600 mg/kg dried plant material. consumption of the plants containing atr or carboxyatractyloside (carboxyatr) has caused fatal renal proximal tubule necrosis and/or centrilobular hepatic necrosis in man and far ... | 1998 | 9651051 |
| intermittent light irradiation with a second-scale interval enhances caffeine production by coffea arabica cells | we developed novel equipment that intermittently illuminates coffea arabica cell suspensions at a second-scale interval and investigated how intermittent irradiation enhances caffeine biosynthesis by c. arabica cells. the light/dark cycles consisting of 2 s of illumination and 18 s of darkness enhanced caffeine production, reaching the same level as for continuous light. the intermittent illumination increased the production efficiency regarding light consumption by a factor of 10. caffeine prod ... | 1998 | 9758671 |
| isolation of a paracoccidioides brasiliensis strain from the soil of a coffee plantation in ibiá, state of minas gerais, brazil. | paracoccidioides brasiliensis has rarely been isolated from its habitat in rural areas. in order to investigate the hypothesis that human infection with this fungus is linked to coffee plantations (coffea arabica), material was collected monthly over a period of 1 year from farms in the town of ibiá, state of minas gerais, brazil. a total of 760 samples of soil, coffee leaves and fruits was cultured and inoculated into mice. a fungus isolated from the liver of a mouse inoculated with soil showed ... | 1998 | 9776810 |
| molecular characterisation and origin of the coffea arabica l. genome. | restriction fragment length polymorphism (rflp) markers were used in combination with genomic in situ hybridisation (gish) to investigate the origin of the allotetraploid species coffea arabica (2n = 44). by comparing the rflp patterns of potential diploid progenitor species with those of c. arabica, the sources of the two sets of chromosomes, or genomes, combined in c. arabica were identified. the genome organisation of c. arabica was confirmed by gish using simultaneously labelled total genomi ... | 1999 | 10102360 |
| xanthine degradation and related enzyme activities in leaves and fruits of two coffea species differing in caffeine catabolism. | the degradation of xanthine was studied in young and aged leaves and in immature and mature fruits of coffea arabica and coffea dewevrei, which differ with respect to caffeine catabolism. radioisotope feeding experiments showed that leaves degraded xanthine more readily than fruits but that mature fruits and aged leaves were less efficient than younger tissues. in all cases, a significant part of the recovered radioactivity was in the ureides. xanthine dehydrogenase was characterized as the enzy ... | 1999 | 10552461 |
| biosynthesis and catabolism of caffeine in low-caffeine-containing species of coffea. | leaves of coffea salvatrix, coffea eugenioides, and c. bengalensis contain approximately 3-7-fold lower levels of caffeine than those of coffea arabica. there was more extensive biosynthesis of caffeine from [8-(14)c]adenine in young leaves of c. arabica than in c. salvatrix, c. eugenioides, and c. bengalensis. degradation of [8-(14)c]caffeine, which is negligible in leaves of c. arabica, was also very slow in c.salvatrix and c. bengalensis. in contrast, [8-(14)c]caffeine was catabolized rapidly ... | 1999 | 10552667 |
| sensory study on the character impact odorants of roasted arabica coffee. | the potent odorants were quantified in a sample of roasted arabica coffee. on the basis of the results, 27 odorants were dissolved in an oil/water mixture. the flavor profile of the model obtained was very close to that of the real sample. in duo and triangle tests, the model was compared with models missing one or more odorants. these experiments indicated that 2-furfurylthiol, 4-vinylguaiacol, several alkyl pyrazines, furanones, acetaldehyde, propanal, methylpropanal, and 2- and 3-methylbutana ... | 1999 | 10563955 |
| potent odorants of raw arabica coffee. their changes during roasting. | aroma extract dilution analysis of raw arabica coffee revealed 3-isobutyl-2-methoxypyrazine (i), 2-methoxy-3,5-dimethylpyrazine (ii), ethyl 2-methylbutyrate (iii), ethyl 3-methylbutyrate (iv), and 3-isopropyl-2-methoxypyrazine (v) as potent odorants. the highest odor activity value was found for i followed by ii, iv, and v. it was concluded that i was responsible for the characteristic, peasy odor note of raw coffee. twelve odorants occurring in raw coffee and (e)-beta-damascenone were also quan ... | 2000 | 10725165 |
| single-locus inheritance in the allotetraploid coffea arabica l. and interspecific hybrid c. arabica x c. canephora. | molecular cytogenetic analysis has indicated that coffea arabica is an amphidiploid formed from the hybridization between two closely related diploid progenitor species, c. canephora and c. eugenioides. our aim was to determine the mode of inheritance in c. arabica and in a tetraploid interspecific hybrid (called arabusta) between c. arabica and c. canephora as revealed by segregation analyses of restriction fragment length polymorphism (rflp) loci markers. the observed rflp allele segregations ... | 2007 | 10739135 |
| in vitro antioxidant and ex vivo protective activities of green and roasted coffee. | the antioxidant properties of green and roasted coffee, in relation to species (coffea arabica and coffea robusta) and degree of roasting (light, medium, dark), were investigated. these properties were evaluated by determining the reducing substances (rs) of coffee and its antioxidant activity (aa) in vitro (model system beta-carotene-linoleic acid) and ex vivo as protective activity (pa) against rat liver cell microsome lipid peroxidation measured as tba-reacting substances. rs of c. robustasam ... | 2000 | 10820041 |
| ochratoxin formation in aspergillus ochraceus with particular reference to spoilage of coffee. | production of ochratoxin on media by eight isolates of aspergillus ochraceus from coffee or its processing environment in india, indonesia, kenya, and brazil, and seven brazilian isolates from other commodities, has been compared with yields in shaken fermentation on shredded wheat and coffee (coffea arabica). shredded wheat most consistently allowed expression of biosynthesis of ochratoxins a and b in yields up to 3.5% of the dry product. culture on artificial media was an unreliable predictor ... | 2000 | 10857930 |
| [coffea arabica--production, botanical classification, new components and active agents and their pharmacological effects]. | the present paper surveys the latest knowledge about coffee grains (coffea arabica) as an important part of our everyday life. it lists the botanical classification of its principal species, such as coffea arabica, coffea robusta, and coffea liberica, the most important improved cultivars of production species in the world. the review paper also discusses the economic aspect, lists the most important regions of production, the optimal and farming technological conditions. it points out the occur ... | 2000 | 10953453 |
| characterization of microsatellite loci in coffea arabica and related coffee species. | 2000 | 10964241 | |
| microbial diversity during maturation and natural processing of coffee cherries of coffea arabica in brazil. | the magnitude and diversity of the microbial population associated with dry (natural) processing of coffee (coffea arabica) has been assessed during a 2-year period on 15 different farms in the sul de minas region of brazil. peptone water-washed samples were taken of maturing cherries on trees (cherries, raisins and dried cherries) and from ground fermentations. the microbial load varied from 3 x 10(4) to 2.2 x 10(9) cfu/cherry with a median value of 1.6 x 10(7) cfu/cherry. the microbial load in ... | 2000 | 11016614 |
| parasitoids of medfly, ceratitis capitata, and related tephritids in kenyan coffee: a predominantly koinobiont assemblage. | arabica coffee was sampled from two sites in the central highlands of kenya (rurima, ruiru) and one site on the western side of the rift valley (koru). three species of ceratitidine tephritidae, ceratitis capitata (wiedemann), c. rosa karsch and trirhithrum coffeae bezzi, were reared from sites in the central highlands, and an additional species, c. anonae graham, was recovered from the western-most site. ten species of parasitic hymenoptera were reared from these tephritids. the parasitoid asse ... | 2000 | 11107253 |
| characterization of polyphenol oxidase in coffee. | polyphenol oxidase (ppo) was characterized in partially purified extracts of leaves (ppo-l) and fruit endosperm (ppo-e) of coffee (coffea arabica l.). ppo activity was higher in early developmental stages of both leaves and endosperm of fruits. wounding or exposure of coffee leaves to methyl jasmonate increased ppo activity 1.5-4-fold. ppo was not latent and was not activated by protease treatment. ppo activity was stimulated 10-15% with sodium dodecyl sulphate (sds) at 0.35-1.75 mm, but at high ... | 2000 | 11117875 |
| the synthesis, testing and use of 5-fluoro-alpha-d-galactosyl fluoride to trap an intermediate on green coffee bean alpha-galactosidase and identify the catalytic nucleophile. | 5-fluoro-alpha-d-galactopyranosyl fluoride was synthesized and its interaction with the active site of an alpha-galactosidase from green coffee bean (coffea arabica), a retaining glycosidase, characterized kinetically and structurally. the compound behaves as an apparently tight binding (ki = 600 nm) competitive inhibitor, achieving this high affinity through reaction as a slow substrate that accumulates a high steady-state concentration of the glycosyl-enzyme intermediate, as evidenced by esims ... | 2000 | 11128583 |
| polysaccharides of green arabica and robusta coffee beans. | two independent procedures for the quantitative determination of the polysaccharide content of arabica caturra (coffea arabica var. caturra) and robusta rom (coffea canephora var. rom) green coffee beans showed that they both contained identical amounts of polysaccharide. cell wall material (cwm) was prepared from the beans and partial solubilisation of component polysaccharides was effected by sequential extraction with water, 1 m koh, 0.3% naclo2, 4 m koh and 8 m koh. the monosaccharide compos ... | 2001 | 11217967 |
| chemical characterization of the high molecular weight material extracted with hot water from green and roasted arabica coffee. | the polysaccharides present in coffee infusions are known to contribute to the organoleptic characteristics of the drink, such as the creamy sensation perceived in the mouth known as "body", the release of aroma substances, and the stability of espresso coffee foam. to increase the knowledge about the origin, composition, and structure of the polysaccharide fraction, the high molecular weight material (hmwm) was extracted with hot water from two green and roasted ground arabica coffees: costa ri ... | 2001 | 11308325 |
| optimizing headspace temperature and time sampling for identification of volatile compounds in ground roasted arabica coffee. | equilibration time and temperature were the factors studied to choose the best conditions for analyzing volatiles in roasted ground arabica coffee by a static headspace sampling extraction method. three temperatures of equilibration were studied: 60, 80, and 90 degrees c. a larger quantity of volatile compounds was extracted at 90 degrees c than at 80 or 60 degrees c, although the same qualitative profile was found for each. the extraction of the volatile compounds was studied at seven different ... | 2001 | 11312865 |
| chlorogenic acids as a potential criterion in coffee genotype selections. | a systematic study by hplc was conducted to determine the content of chlorogenic acids in green coffee beans of the variedad colombia (coffea arabica caturra var. x híbrido de timor) and in other genotypes of interest of c. arabica, coffea canephora, híbrido de timor, and the f1 offspring derived from the crossing caturra x híbrido de timor. comparisons were made of the total content of these acids, their quantitative differences, and the presence or absence of some of them, using parametric sta ... | 2001 | 11368619 |
| comparison of the antioxidant activity of commonly consumed polyphenolic beverages (coffee, cocoa, and tea) prepared per cup serving. | in this study, the in vitro low-density lipoprotein oxidation model was used to assess the relative antioxidant activity of the polyphenolic beverages tea, coffee, and cocoa on a cup-serving basis. the beverages were prepared as 0.7-2.5% soluble coffee and 1.5-3.5% cocoa; teas (green, black, or herbal) were prepared as one tea bag infused over 5 min in 220 ml of hot water. under these standard cup serving conditions, the antioxidant activity as determined by the lag time was in the range of 292- ... | 2001 | 11453788 |
| origin, diversity and evolution of nbs-type disease-resistance gene homologues in coffee trees (coffea l.). | the majority of plant disease-resistance genes (r-genes) isolated so far encode a predicted nucleotide-binding site (nbs) domain. nbs domains related to r-genes show a highly conserved backbone of amino acid motifs, which makes it possible to isolate resistance gene analogues (rgas) by pcr with degenerate primers. multiple combinations of primers with low degeneracy, designed from two conserved motifs in the nbs regions of r-genes of various plants, were used on genomic dna from coffee trees, an ... | 2001 | 11459185 |
| molecular and biochemical characterization of endo-beta-mannanases from germinating coffee (coffea arabica) grains. | the activity of endo-beta-mannanase ([1-->4]-beta-mannan endohydrolase ec 3.2.1.78) is likely to be central to the metabolism of cell wall mannans during the germination of grains of coffee (coffea spp.). in the present paper, we report the cloning and sequencing of two endo-beta-mannanase cdnas (mana and manb) by different strategies from coffea arabica l.. the mana cdna was obtained by the use of oligonucleotides homologous to published sequences of other endo-beta-mannanases and manb by the u ... | 2001 | 11469596 |
| novel nitrogen-fixing acetic acid bacteria, gluconacetobacter johannae sp. nov. and gluconacetobacter azotocaptans sp. nov., associated with coffee plants. | diazotrophic bacteria were isolated, in two different years, from the rhizosphere and rhizoplane of coffee (coffea arabica l.) plants cultivated in mexico; they were designated as type dor and type sad isolates. they showed characteristics of the family acetobacteraceae, having some features in common with gluconacetobacter (formerly acetobacter) diazotrophicus, the only known n2-fixing species of the acetic acid bacteria, but they differed from this species with regard to several characteristic ... | 2001 | 11491326 |
| trueness-to-type and agronomic characteristics of coffea arabica trees micropropagated by the embryogenic cell suspension technique. | trueness-to-type and agronomic characteristics of trees of four coffee (coffea arabica l.) f(1) hybrid clones derived from embryogenic cell suspensions were compared with those of trees produced from in vitro microcuttings. three types of variants were observed among the 644 trees derived from embryogenic suspensions. total frequency of the variants was 2.1% for trees originating from embryogenic cell suspensions, whereas no variant was found among the trees produced from microcuttings. the vari ... | 2001 | 11560816 |
| potential for areawide integrated management of mediterranean fruit fly (diptera: tephritidae) with a braconid parasitoid and a novel bait spray. | the braconid wasp, fopius arisanus (sonan), a biological control agent for mediterranean fruit fly, ceratitis capitata (wiedemann), was studied in coffee, coffea arabica l. fopius arisanus, comprised 79.3% of the total parasitoids (7,014) recovered from fruits collected at three small coffee farms. data from seasonal host/parasitoid studies at a large coffee plantation also suggested that the most effective natural enemy of c. capitata in coffee may now reside in hawaii. the original parasitoids ... | 2001 | 11561838 |
| 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 ... | 2007 | 11577895 |
| multivariate methods for characterization and classification of espresso coffees from different botanical varieties and types of roast by foam, taste, and mouthfeel. | three espresso coffee (ec) samples of different botanical varieties and types of roast were prepared in standard conditions using an experimental ec prototype: arabica coffee, robusta natural blend, and robusta torrefacto blend (a special roast by adding sugar). the ecs were characterized with regard to the physical parameters, amount of total solids, total solids on filtrate, lipids, caffeine, trigonelline, and chlorogenic acids by hplc, and sensory descriptive analysis related to foam appearan ... | 2001 | 11600016 |
| characterization of espresso coffee aroma by static headspace gc-ms and sensory flavor profile. | the aromas of three espresso coffee (ec) samples from different botanical varieties and types of roast (arabica coffee, robusta natural blend, and robusta torrefacto blend (special roast by adding sugar)) were studied by static headspace gc-ms and sensory flavor profile analysis. seventy-seven compounds were identified in all of the ec samples. among them, 13 key odorants have been quantified and correlated with their flavor notes by applying multivariate statistical methods. some correlations h ... | 2001 | 11714340 |
| headspace sorptive extraction (hsse), stir bar sorptive extraction (sbse), and solid phase microextraction (spme) applied to the analysis of roasted arabica coffee and coffee brew. | headspace sorptive extraction (hsse) and stir bar sorptive extraction (sbse), two recently introduced solventless enrichment techniques, have been applied to the analysis of the headspace of arabica roasted coffee and of the headspace of the brew and of the brew itself. in both hsse and sbse enrichment is performed on a thick film of poly(dimethylsiloxane) (pdms) coated onto a magnet incorporated in a glass jacket. sampling is done by placing the pdms stir bar in the headspace (gas phase extract ... | 2002 | 11804511 |
| coffee bean arabinogalactans: acidic polymers covalently linked to protein. | the arabinogalactan content of green coffee beans (coffea arabica var. yellow caturra) was released by a combination of chemical extraction and enzymatic hydrolysis of the mannan-cellulose component of the wall. several arabinogalactan fractions were isolated, purified by gel-permeation and ion-exchange chromatography and characterised by compositional and linkage analysis. the ag fractions contained between 6 and 8% glucuronic acid, and gave a positive test for the beta-glucosyl-yariv reagent, ... | 2002 | 11844494 |
| alkylpyridiniums. 2. isolation and quantification in roasted and ground coffees. | recent model studies on trigonelline decomposition have identified nonvolatile alkylpyridiniums as major reaction products under certain physicochemical conditions. the quaternary base 1-methylpyridinium was isolated from roasted and ground coffee and purified by ion exchange and thin-layer chromatography. the compound was characterized by nuclear magnetic resonance spectroscopy ((1)h, (13)c) and mass spectrometry techniques. a liquid chromatography-electrospray ionization tandem mass spectromet ... | 2002 | 11853504 |
| antiadhesive effect of green and roasted coffee on streptococcus mutans' adhesive properties on saliva-coated hydroxyapatite beads. | green and roasted coffees of the two most used species, coffea arabica and coffea robusta, several commercial coffee samples, and known coffee components were analyzed for their ability to interfere with streptococcus mutans' sucrose-independent adsorption to saliva-coated hydroxyapatite (ha) beads. all coffee solutions showed high antiadhesive properties. the inhibition of s. mutans' adsorption to ha beads was observed both when coffee was present in the adsorption mixture and when it was used ... | 2002 | 11853508 |
| effect of roasting on degradation and structural features of polysaccharides in arabica coffee beans. | the degree and nature of polysaccharide degradation at different roasting levels was determined for three arabica (coffea arabica) bean varieties. between 12 and 40% of the bean polysaccharides were degraded depending on the roasting conditions. the thermal stability of the arabinogalactans, (galacto)mannans and cellulose was markedly different. the arabinogalactans and mannans were degraded up to 60 and 36%, respectively, after a dark roast, while cellulose showed negligible evidence of degrada ... | 2002 | 11861016 |
| chemical characterization of galactomannans and arabinogalactans from two arabica coffee infusions as affected by the degree of roast. | galactomannans and arabinogalactans compose almost exclusively the polysaccharide fraction of roasted coffee infusions. to increase the knowledge about the effect of the degree of roast (dr) in the amount and chemical structure of the galactomannans and arabinogalactans, two arabica coffees of different geographical origins (costa rica and brazil) were roasted for three degrees of roast (drs 4.7-5.0, 8.7, and 10% of dry weight loss of green coffee beans, on a dry basis). the high molecular weigh ... | 2002 | 11879015 |
| differential gene expression during somatic embryogenesis in coffea arabica l., revealed by rt-pcr differential display. | molecular and biochemical studies of somatic embryogenesis may help to shed light on the mechanisms governing this phenomenon. in this article, a differential display analysis approach was employed to investigate the changes taking place during the induction of somatic embryogenesis in leaf explants and suspension cultures of coffee. cloned fragments show homologies to several proteins reported in databases, but only one has previously been described as regulated during somatic embryogenesis. by ... | 2002 | 11989658 |
| 3-methylbutanoyl and 3-methylbut-2-enoyl disaccharides from green coffee beans (coffea arabica). | three 3-methylbutanoyl and 3-methylbut-2-enoyl disaccharides isolated from green coffee beans (coffea arabica) were identified as 3-methylbutanoyl-1-o-beta-d-glucopyranosyl-beta-d-apiofuranoside, 3-methylbutanoyl-6-o-alpha-d-glucopyranosyl-beta-d-fructofuranoside, and 3-methylbut-2-enoyl-1-o-beta-d-glucopyranosyl-beta-d-apiofuranoside. the structures were established by one- and two-dimensional 1h and 13c nmr spectra as well as by esi ms/ms spectra. | 2002 | 12031434 |
| effect of roasting on the antioxidant activity of coffee brews. | colombian arabica coffee beans were roasted to give light, medium, and dark samples. their aqueous extracts were analyzed by gel filtration chromatography, uv-visible spectrophotometry, capillary electrophoresis, and the abts(*)(+) assay. a progressive decrease in antioxidant activity (associated mainly with chlorogenic acids in the green beans) with degree of roasting was observed with the simultaneous generation of high (hmm) and low molecular mass (lmm) compounds possessing antioxidant activi ... | 2002 | 12059145 |
| the value of bees to the coffee harvest. | the self-pollinating african shrub coffea arabica, a pillar of tropical agriculture, was considered to gain nothing from insect pollinators. but i show here that naturalized, non-native honeybees can augment pollination and boost crop yields by over 50%. these findings, together with world coffee-harvest statistics and results from field studies of organically shade-grown coffee, indicate that coffee plants would benefit from being grown in habitats that are suitable for sustaining valuable poll ... | 2002 | 12066176 |
| comparison of somatic embryogenesis-derived coffee (coffea arabica l.) plantlets regenerated in vitro or ex vitro: morphological, mineral and water characteristics. | coffea arabica l. plantlets obtained ex vitro after sowing somatic embryos produced in a bioreactor in horticultural substrate were compared with those obtained in vitro from the same embryo population under conventional culturing conditions on semi-solid media. the intensity and quality of aerial and root system development were compared. shoot emergence was more efficient in vitro but rooting frequencies were low. in contrast, all ex vitro-regenerated embryos rooted. the cotyledon area of matu ... | 2002 | 12125775 |
| on the role of (-)-2-methylisoborneol for the aroma of robusta coffee. | the role of 2-methylisoborneol (mib) in coffee aroma is controversially discussed in the literature. mib is known as an off-flavor compound in drinking water and food, but it has also been suggested as a key flavor component of robusta coffee, discriminating robusta from arabica coffee. to check this hypothesis the role of mib in coffee brews was studied. two reference samples containing pure arabica and robusta coffee brews were compared with five samples of arabica coffee brews containing incr ... | 2002 | 12137492 |
| beneficial effect of post -thawing osmoconditioning on the recovery of cryopreserved coffee (coffea arabica l.) seeds. | osmoconditioning-controlled rehydration of seeds in a solution with low osmotic potential -has been shown to reinvigorate aged seeds. the present work aimed at investigating the effect of osmoconditioning on the germination of cryopreserved seeds of coffea arabica, whose viability and vigour are drastically affected by cryopreservation. for cryopreservation, seeds were desiccated to 0.21 g h2o/g dw, cooled at 1 degree c/min to -50 degree c, then immersed rapidly in liquid nitrogen. after rapid r ... | 2002 | 12148064 |
| biosynthesis of caffeine in leaves of coffee. | the levels of endogenous caffeine and theobromine were much higher in buds and young leaves of coffea arabica l. cv kent than in fully developed leaves. biosynthesis of caffeine from 14c-labeled adenine, guanine, xanthosine, and theobromine was observed, whereas other studies (h. ashihara, a.m. monteiro, t. moritz, f.m. gillies, a. crozier [1996] planta 198: 334-339) have indicated that there is no detectable incorporation of label into caffeine when theophylline and xanthine are used as substra ... | 1996 | 12226327 |
| regulation of purine metabolism in intact leaves of coffea arabica. | the capacity of coffea arabica leaves (5- x 5-mm pieces) to synthesize de novo and catabolize purine nucleotides to provide precursors for caffeine (1,3,7-trimethylxanthine) was investigated. consistent with de novo synthesis, glycine, bicarbonate, and formate were incorporated into the purine ring of inosine 5[prime]-monophosphate (imp) and adenine nucleotides ([sigma]ade); azaserine, a known inhibitor of purine de novo synthesis, inhibited incorporation. activity of the de novo pathway in c. a ... | 1993 | 12232012 |
| separate de novo and salvage purine pools are involved in the biosynthesis of theobromine but not caffeine in leaves of coffea arabica l. | in coffea arabica leaves, the purine ring of theobromine (3,7-dimethylxanthine) and caffeine (1,3,7-trimethylxanthine) is provided by de novo purine biosynthesis: (a) [14c]glycine, [14c]bicarbonate, and [14c]formate were incorporated into inosine 5[prime]- monophosphate (imp), sum of adenine nucleotides ([sigma]ade), theobromine, and caffeine; and (b) incorporation of [14c]formate into imp, [sigma]ade, theobromine, and caffeine was inhibited by azaserine, a known inhibitor of de novo purine bios ... | 1993 | 12232013 |
| [bacterial present in the xylem of coffee (rubiaceae: coffea arabica) with "crespera" disease]. | "crespera" is an infectious disease of coffee plants that affects both the coffee production and the economy of the coffee producer countries. this disease affects morphologically the plant: long and narrow leaves with wavy borders and marginal necrosis; strong chlorosis results in drying of the leave, and leads to bad conditions of the plant. the internodes are short, producing the appearance of multiple sprouts in the axial sprout, the flowers can turn greenish, and the plant can present branc ... | 2002 | 12298265 |
| alpha-galactosidase from cultured rice (oryza sativa l. var. nipponbare) cells. | the alpha-galactosidase from rice cell suspension cultures was purified to homogeneity by different techniques including affinity chromatography using n-epsilon-aminocaproyl-alpha-d-galactopyranosylamine as the ligand. from 11 l of culture filtrate, 28.7 mg of purified enzyme was obtained with an overall yield of 51.9%. the cdna coding for the alpha-galactosidase was cloned and sequenced. the enzyme was found to contain 417 amino acid residues composed of a 55 amino acid signal sequence and 362 ... | 2002 | 12423882 |
| chemical characterization of the high-molecular-weight material extracted with hot water from green and roasted robusta coffees as affected by the degree of roast. | the hot-water-soluble polymeric material from green and roasted uganda robusta coffees submitted to different degrees of roasting was isolated and characterized, and the changes in structure and amount of galactomannans and arabinogalactans were determined and discussed in relation to the data already available for arabica coffees, obtained under the same experimental conditions. the content of arabinogalactans extracted from robusta green coffee was higher than that extracted from arabica. for ... | 2002 | 12428958 |
| origin assessment of green coffee (coffea arabica) by multi-element stable isotope analysis of caffeine. | the delta(13)c(vpdb), delta(2)h(vsmow) and delta(18)o(vsmow) values of caffeine isolated from arabica green coffee beans of different geographical origin have been determined by isotope ratio mass spectrometry (irms) using elemental analysis (ea) in the "combustion" (c) and "pyrolysis" (p) modes (ea-c/p-irms). in total, 45 coffee samples (20 from central and south america, 16 from africa, six from indonesia, and three from jamaica and hawaii) were analysed, as well as three reference samples of ... | 2002 | 12434246 |
| gene introgression into coffea arabica by way of triploid hybrids (c. arabica x c. canephora). | interspecific triploid hybrid plants between the tetraploid species coffea arabica l. and the diploid species c. canephora p. were backcrossed to c. arabica. although characterised by a low production and an important fruit dropping, all attempted crosses (ie, 6) generated bc(1) progenies. flow cytometric analysis of the nuclear dna content revealed that most of the bc1 individuals were nearly tetraploid. among the male gametes produced by the interspecific triploid hybrids, those presenting a h ... | 2002 | 12466993 |
| isolation of a new dual-functional caffeine synthase gene encoding an enzyme for the conversion of 7-methylxanthine to caffeine from coffee (coffea arabica l.). | in coffee and tea plants, caffeine is synthesized from xanthosine via a pathway that includes three methylation steps. we report the isolation of a bifunctional coffee caffeine synthase (ccs1) clone from coffee endosperm by reverse transcription-polymerase chain reaction (rt-pcr) and rapid amplification of cdna ends (race) technique using previously reported sequence information for theobromine synthases (ctss). the predicted amino acid sequences of ccs1 are more than 80% identical to ctss and a ... | 2003 | 12527364 |
| aflp analysis of genetic diversity within and among coffea arabica cultivars. | genetic diversity of coffea arabica cultivars was estimated using amplified fragment length polymorphism (aflp) markers. sixty one coffea accessions composed of six arabica cultivars, including typica, bourbon, catimor, catuai, caturra and mokka hybrid, plus two diploid coffea species, were analyzed with six ecori- msei primer combinations. a total of 274 informative aflp markers were generated and scored as binary data. these data were analyzed using cluster methods in the software package ntsy ... | 2002 | 12582521 |
| the origin of cultivated coffea arabica l. varieties revealed by aflp and ssr markers. | molecular markers were used to assess polymorphism between and within the genetic bases of coffee (i.e. typica and bourbon) spread from yemen since the early 18th century that have given rise to most arabica cultivars grown world-wide. eleven coffea arabica accessions derived from the disseminated bases were evaluated by amplified fragment length polymorphism (aflp) using 37 primer combinations and simple-sequence repeats (ssrs) produced by six microsatellites. four cultivars growing in yemen an ... | 2002 | 12582651 |
| introgression into the allotetraploid coffee ( coffea arabica l.): segregation and recombination of the c. canephora genome in the tetraploid interspecific hybrid ( c. arabicax c. canephora). | transfer of desired characters from the diploid relative species such as coffea canephora into the cultivated allotetraploid coffee species ( coffea arabica l.) is essential to the continued improvement of varieties. behaviour of the c. canephora genome and its interaction with the c. arabica genome were investigated in tetraploid interspecific hybrids ( c. arabicax c. canephora 4 x) resulting from a cross between an accession of c. arabica and a tetraploid plant of c. canephora obtained followi ... | 2002 | 12582671 |
| culture-induced variation in plants of coffea arabica cv. caturra rojo, regenerated by direct and indirect somatic embryogenesis. | amplified fragment-length polymorphism (aflp) was used to evaluate the stability of dna in regenerated plantlets of coffea arabica obtained by direct (dse) and indirect somatic embryogenesis (ise). cluster analysis using the unweighted pair-group method (upgma), showed no specific grouping pattern related to the type of embryogenesis. these results suggest that the somatic embryogenesis (se) process has a mechanism for the selection of normal and competent cells. bulked dna from regenerated plan ... | 2003 | 12632695 |
| somaclonal variation in coffea arabica: effects of genotype and embryogenic cell suspension age on frequency and phenotype of variants. | we determined how age of embryogenic cell suspensions affects somaclonal variation in five f1 hybrids of coffea arabica l. batches of plants were produced either directly from embryogenic callus, or after 3, 6, 9 and 12 months of embryogenic cell suspension culture. seven phenotypic variants were characterized. based on vigor and productivity of the regenerated plants, we classified the variants in order of increasing severity of physiological disorders as: juvenile leaf color, giant, dwarf, thi ... | 2003 | 12642244 |
| water utilization, plant hydraulic properties and xylem vulnerability in three contrasting coffee (coffea arabica) cultivars. | water use, hydraulic properties and xylem vulnerability to cavitation were studied in the coffee (coffea arabica l.) cultivars san ramon, yellow caturra and typica growing in the field under similar environmental conditions. the cultivars differed in growth habit, crown morphology and total leaf surface area. sap flow, stomatal conductance (g(s)), crown conductance (g(c)), apparent hydraulic conductance of the soil-leaf pathway (g(t)), leaf water potential (psi(l)) and xylem vulnerability to los ... | 2000 | 12651468 |
| amino acid sequence of the 26 kda subunit of legumin-type seed storage protein of common buckwheat (fagopyrum esculentum moench): molecular characterization and phylogenetic analysis. | the paper describes the amino acid sequence of a 26 kda basic subunit of 13s globulin of common buckwheat (fagopyrum esculentum moench). the protein has 93 and 75% sequence homology with 11s globulin of coffea arabica and beta subunit of 11s globulin of cucurbita pepo respectively. the subunit has the "globally conserved" n-terminal sequence consisting of gly-ile-asp-glu and the cysteine at p7' from the proteolytic processing site. a conserved 7 residue domain of pro-his-trp-asn-ile-asn-ala, cha ... | 2003 | 12657290 |
| identification of odor-active 3-mercapto-3-methylbutyl acetate in volatile fraction of roasted coffee brew isolated by steam distillation under reduced pressure. | in a roasted arabica coffee brew, the potent roasty odor quality compound was identified as 3-mercapto-3-methylbutyl acetate by comparison of its kovats gas chromatography retention index, mass spectrum, and odor quality to those of the synthetic authentic compound. 3-mercapto-3-methylbutyl acetate has been identified for the first time in the coffee, and according to the results of the aroma extract dilution analysis, the contribution of this compound to the flavor of the roasted coffee brew va ... | 2003 | 12720395 |
| molecular cloning and functional characterization of three distinct n-methyltransferases involved in the caffeine biosynthetic pathway in coffee plants. | caffeine is synthesized from xanthosine through n-methylation and ribose removal steps. in the present study, three types of cdnas encoding n-methyltransferases were isolated from immature fruits of coffee (coffea arabica) plants, and designated as caxmt1, camxmt2, and cadxmt1, respectively. the bacterially expressed encoded proteins were characterized for their catalytic properties. caxmt1 catalyzed formation of 7-methylxanthosine from xanthosine with a k(m) value of 78 microm, camxmt2 catalyze ... | 2003 | 12746542 |
| impact of the coffea canephora gene introgression on beverage quality of c. arabica. | lines of coffea arabica derived from the timor hybrid (hybrid between c. arabica and c. canephora) are resistant to coffee leaf rust (hemileia vastatrix) and to the nematode meloidogyne exigua. the introgression of c. canephora resistance genes is suspected of causing a drop in beverage quality. coffee samples from pure lines, compared in a trial 1, and from f1 hybrids and parental lines from a half-diallel trial in a trial 2, were studied for beverage quality, chemical composition and amount of ... | 2003 | 12750771 |
| changes to the galactose/mannose ratio in galactomannans during coffee bean ( coffea arabica l.) development: implications for in vivo modification of galactomannan synthesis. | endosperm was isolated from arabica caturra coffee beans 11, 15, 21, 26, 31 and 37 weeks after flowering, and the chemical composition and relative solubility of its component polysaccharides determined at each growth stage. chemical analysis of the total mannan content of the cell wall material was done after solubilisation of galactomannans by alkaline extraction of the cell wall material followed by enzymatic digestion of the alkali-insoluble residue with a mixture of endo-mannanse and endo-g ... | 2003 | 12783340 |
| fruit set of highland coffee increases with the diversity of pollinating bees. | the worldwide decline of pollinators may negatively affect the fruit set of wild and cultivated plants. here, we show that fruit set of the self-fertilizing highland coffee (coffea arabica) is highly variable and related to bee pollination. in a comparison of 24 agroforestry systems in indonesia, the fruit set of coffee could be predicted by the number of flower-visiting bee species, and it ranged from ca. 60% (three species) to 90% (20 species). diversity, not abundance, explained variation in ... | 2003 | 12803911 |
| genetic diversity of forest arabica coffee (coffea arabica l.) in ethiopia as revealed by random amplified polymorphic dna (rapd) analysis. | genetic diversity within the forest coffea arabica l. gene pool in ethiopia has not been extensively examined with molecular markers. in the present study, a total of 75 polymorphic rapd bands generated by twelve random primers were used to assess genetic diversity among 144 genotypes representing 16 c. arabica populations. the number of polymorphic bands detected with each primer ranged from 2 to 9 with a mean of 6.25 bands per primer. banding patterns ranged in percentage polymorphism from 37% ... | 2003 | 12830983 |
| the first committed step reaction of caffeine biosynthesis: 7-methylxanthosine synthase is closely homologous to caffeine synthases in coffee (coffea arabica l.). | in coffee and tea plants, caffeine is synthesized from xanthosine via a pathway that has three methylation steps. we identified and characterized the gene encoding the enzyme for the first methylation step of caffeine biosynthesis. the full-length cdna of coffee tentative caffeine synthase 1, ctcs1, previously isolated by the rapid amplification of cdna ends was translated with an escherichia coli expression system and the resultant recombinant protein was purified using ni-nta column. the prote ... | 2003 | 12860386 |
| genetic mapping of a caffeoyl-coenzyme a 3-o-methyltransferase gene in coffee trees. impact on chlorogenic acid content. | chlorogenic acids (cga) are involved in the bitterness of coffee due to their decomposition in phenolic compounds during roasting. cga mainly include caffeoyl-quinic acids (cqa), dicaffeoyl-quinic acids (dicqa) and feruloyl-quinic acids (fqa), while cqa and dicqa constitute cga sensu stricto (cga s.s.). in the two cultivated species coffea canephora and coffea arabica, cga s.s. represents 88% and 95% of total cga, respectively. among all enzymes involved in cga biosynthesis, caffeoyl-coenzyme a ... | 2003 | 12861362 |
| toxigenic fungi associated with processed (green) coffee beans (coffea arabica l.). | processed (green) coffee beans from coffea arabica in brazil were assessed for the presence of aspergillus and penicillium species both before and after surface sterilisation, the aflatoxigenic and ochratoxigenic potential of the isolates and ochratoxin a levels. contamination by aspergillus and penicillium species was found on 96% and 42%, respectively, of 45 samples from 11 localities. after disinfection with 1% sodium hypochlorite, the levels fell to 47% and 24%, respectively. one hundred and ... | 2003 | 12878387 |
| changes in some characteristics between the wild and al-tolerant coffee (coffea arabica l.) cell line. | an aluminium (al)-tolerant cell line (lamt) of coffee (coffea arabica l.) was obtained from a cell suspension culture and biochemically and molecularly characterized in an ms medium at half ionic strength and low ph. lamt grew 30% more than the control line (susceptible to al) in the presence of different concentrations of al, showed a lower free al concentration in the medium and had higher phospholipase c specific activity (80%). membrane integrity of the lamt was 50% greater than the control ... | 2003 | 14507462 |
| discrimination between arabica and robusta coffee species on the basis of their amino acid enantiomers. | this work reports the results for the composition of robusta and arabica coffee species in terms of their amino acid enantiomers in the green and roasted states. the analyses were conducted for the free amino acids, as well as for the amino acids obtained after acid hydrolysis. the amino acids were extracted/hydrolyzed and isolated by spe on strong cation exchange columns, derivatized to their n-ethoxycarbonylheptafluorobutyl esters, and analyzed by gas chromatography/fid on a chirasil l-val col ... | 2003 | 14558768 |
| flavanol binding of nuclei from tree species. | light microscopy was used to examine the nuclei of five tree species with respect to the presence of flavanols. flavanols develop a blue colouration in the presence of a special p-dimethylaminocinnamaldehyde (dmaca) reagent that enables those nuclei loaded with flavanols to be recognized. staining of the nuclei was most pronounced in both tsuga canadensis and taxus baccata, variable in metasequoia glyptostroboides, faint in coffea arabica and minimal in prunus avium. hplc analysis showed that th ... | 2004 | 14595514 |
| construction of a genetic map for arabica coffee. | we have used aflps to construct a genetic linkage map on a pseudo-f(2) population of arabica coffee ( coffea arabica l.) derived from a cross between the cultivars mokka hybrid and catimor. sixty trees from this population were selected on the basis of plant height distribution to construct a linkage map. a total of 456 dominant markers and eight co-dominant markers were generated from 288 aflp primer combinations. of the total number of markers generated, 68% were from cv. catimor, 30% from cv. ... | 2004 | 14605810 |
| inhibition of caffeine biosynthesis in tea (camellia sinensis) and coffee (coffea arabica) plants by ribavirin. | the effects of ribavirin, an inhibitor of inosine-5'-monophosphate (imp) dehydrogenase, on [8-(14)c]inosine metabolism in tea leaves, coffee leaves and coffee fruits were investigated. incorporation of radioactivity from [8-(14)c]inosine into purine alkaloids, such as theobromine and caffeine, guanine residues of rna, and co(2) was reduced by ribavirin, while incorporation into nucleotides, including imp and adenine residues of rna, was increased. the results indicate that inhibition of imp dehy ... | 2003 | 14623114 |
| genetic diversity in tanzanian arabica coffee using random amplified polymorphic dna (rapd) markers. | dna from coffea arabica leaves was used for rapd analysis and a total of 144 leaf samples collected from 16 provenances in five regions of tanzania were analysed. ten arbitrary 10 mer primers were employed in the analysis and they produced a total of 86 fragments. fragment sizes ranged from 100-1400 bp. the resulting dissimilarity matrix revealed values ranging from 0.11 to 1, while the average was 0.66. the cophenetic matrix and the original dissimilarity matrix showed a significant correlation ... | 2003 | 14641474 |
| aluminium differentially modifies lipid metabolism from the phosphoinositide pathway in coffea arabica cells. | the effect of aluminium (al) on phosphoinositide-specific phospholipase c (plc) and lipid kinase activities was examined in a cellular suspension of coffee. two main effects were seen when cells were treated with alcl3. in periods as short as 1 minute, al-exposed cells increased the activity of plc and ip3 formation up to two fold. over longer periods plc activity was inhibited by more than 50%. the activity of phosphatidylinositol 4-kinase (pl 4-k), phosphatidylinositol phosphate 5-kinase (pip ... | 2003 | 14658381 |
| flavoring components of raw monsooned arabica coffee and their changes during radiation processing. | volatile aroma principles, nonvolatile taste constituents (caffeine and chlorogenic and caffeic acids), and glycosidically bound aroma compounds of monsooned and nonmonsooned raw arabica coffee were analyzed using gas chromatography-mass spectrometry (gc-ms) and high-performance liquid chromatography (hplc). among the most potent odor active constituents known to contribute to the aroma of the green beans, 3-isopropyl-2-methoxypyrazine, 3-isobutyl-2-methoxypyrazine, 4-vinylguaiacol, beta-damasce ... | 2003 | 14690378 |
| incidence of microflora and of ochratoxin a in green coffee beans (coffea arabica). | coffee is produced in tropical countries around the equator where climatic conditions are favourable for fungal development and mycotoxin production; however, mycotoxins do not only occur in the tropical countries. the aim was to evaluate the mycoflora and possible incidence of ochratoxin a (ota) in 60 samples of green coffee beans from brazil. the mycological evaluation was carried out using a conventional method and the ota was determined using sequential phenyl silane and immunoaffinity colum ... | 2003 | 14726276 |