Purine alkaloids in Paullinia (original) (raw)
Related papers
Economic Botany, 1998
Guarands, the carbonated beverages (sodas) of choice throughout much of Brazil, are mandated by Brazilian law to contain at least 300 mg guarand (Paullinia cupana, Sapindaceae) seed per 100 ml soda. Were all the soda manufacturers adhering to the law, they would be consuming almost three times the annual production of seed. Guarand seeds contain unusually high levels of caffeine, along with smaller amounts of the related purine alkaloids theobromine and theophylline. We investigated the purine alkaloid content of three ethnobotanical guarand collections and 39 commercial products using HPLC/UV. Many of the products did contain caffeine as the major alkaloid, with traces of theobromine and theophylline. Numerous sodas and syrups contained up to ten times more theobromine than caffeine, and we suspect that these products were adulterated with cacao (Theobroma cacao, Sterculiaceae), the major source of theobromine. TEOBROMINA, TEOFILINA, E CAFEiNA EM 42 AMOSTRAS E PRODUTOS DE GUARAN,/~ (PAULLINIA CU-PANA, SAPINDACEAE). O guarand, refrigerante preferido em boa parte do Brasil, d obrigado por ldi a conter no m{nimo 300 mg de semente de guarand (Paullinia cupana, Sapindaceae) por 100 ml de refrigerante. Se todos os fabricantes seguissem esta lgi eles estariam consumindo quase trYs vezes a produ96o anual de sementes. As sementes de guarand usualmente contdm altos n{veis de cafe{na e pequenas quantidades de outras duas substCmcias relacionadas, os alka16ides teobromina e teofilina. 0 contetido do alkal6ide purina foi pesquisado em trds amostras etnobot&nicas de guarand e 39 produtos comerciais usando HPLC/UV. Muitos destes produtos contdm a cafe{na como o alkal6ide principal, corn tragos de teobromina e teofilina. Algumas refrigerantes e xaropes releveram um conteddo de atd dez vezes mais teobromina que cafe{na e suspeita-se que estes produtos foram adulterados corn cacau (Theobroma cacao, Sterculiaceae), a princo~al fonte de teobromina.
Guarana: Revisiting a highly caffeinated plant from the Amazon
Journal of Ethnopharmacology, 2013
Ethnopharmacological relevance: Guarana (Paullinia cupana Kunth var. sorbilis (Mart.) Ducke) has been traditionally consumed by indigenous communities of the Amazon region. It is valued mainly for its stimulant property because of its high content of caffeine, which can be up to 6% in the seeds. Aim of the review: The purpose of this review is to revisit this typically Brazilian plant, addressing economic considerations, the chemical makeup of the seeds and pharmacological properties so far investigated. Results: Guarana is primarily produced in the Brazilian states of Amazonas and Bahia, and approximately 70% of the production is used by the industry of soft and energy drinks. The other 30% becomes guarana powder for direct consumption in capsules or dilution in water, or it serves as a raw material for the pharmaceutical and cosmetics industries. In addition to its stimulant property, guarana has other therapeutic properties, which have aroused the interest of the scientific community. Conclusion: This review shows that other guarana properties may be explored and how scarce are the studies regarding agronomic, plant pathology, physiology and breeding. So far, caffeine has been the main reason to study guarana and still will lead the researches because the demand for this alkaloid by food and pharmaceutical industry, and a strongly growing market related with beauty products. However, guarana has other components and there is great interest in studies designed to elucidate the effects of guarana′s bioactive components and their potential pharmacological applications.
Plant Foods for Human Nutrition, 2003
Marked differences regarding both caffeine and theobromine contents of mate leaves (Ilex paraguariensis) were found among 230 mass selected candidate trees distributed across 5 plantations in the region of Misiones, Argentina. In the vast majority of the analyzed samples, the caffeine concentrations ranged within the established limits for mate leaves, however theobromine contents (average content 0.96%) generally surpassed literature figures so far published . By means of a simple cluster analysis using "group average" as the clustering algorithm, the samples were divided into eight different groups according to the contents of both purine alkaloids. Based upon this division it will be possible to pick appropriate genotypes for breeding ideotypes which meet more precisely the different specific consumer expectations.
Caffeine Biosynthesis and Purine Metabolism in Leaves of Mascarocoffea Species
European Chemical Bulletin, 2017
Caffeine, a purine alkaloid, was not detected in leaves of two Mascarocoffea species, Coffea millotii and Coffea perrieri. Trigonelline, a pyridine alkaloid, occurred in these species, but the levels (3−4 μmol g-1 fresh weight) were much lower than that of Robusta coffee (Coffea canephora) (36 μmol g-1 fresh weight). Feeding experiments with [8-14 C]adenine indicated that purine alkaloid biosynthesis was terminated at 7-methylxanthine formation and as a consequence theobromine and caffeine were not produced in Coffea millotii and Coffea perrieri. The adenine salvage activity was lower, but its degradation activity was higher in leaves of these Mascarocoffea species than those in Coffea canephora. The metabolic fate of the purine nucleosides, [8-14 C]inosine, [8-14 C]guanosine and [8-14 C]xanthosine was investigated in leaves of Coffea millotii. The biosynthesis of 7-methylxanthine, but not theobromine or caffeine, from these precursors was detected. Large amounts of these purine nucleosides were catabolized via allantoin. Limited amounts of [8-14 C]inosine and [8-14 C]guanosine were salvaged and utilized for RNA synthesis, however, no [8-14 C]xanthosine salvage was observed. Little or no 14 C-metabolites were observed when [8-14 C]theobromine and [8-14 C]caffeine were applied to leaf disks of Coffea millotii. From the results obtained in this study, possible metabolic pathways of purines in Mascarocoffea species are discussed.
Metabolism of alkaloids in coffee plants
Brazilian Journal of Plant Physiology, 2006
Coffee beans contain two types of alkaloids, caffeine and trigonelline, as major components. This review describes the distribution and metabolism of these compounds. Caffeine is synthesised from xanthosine derived from purine nucleotides. The major biosynthetic route is xanthosine → 7-methylxanthosine → 7-methylxanthine → theobromine → caffeine. Degradation activity of caffeine in coffee plants is very low, but catabolism of theophylline is always present. Theophylline is converted to xanthine, and then enters the conventional purine degradation pathway. A recent development in caffeine research is the successful cloning of genes of N-methyltransferases and characterization of recombinant proteins of these genes. Possible biotechnological applications are discussed briefly. Trigonelline (N-methylnicotinic acid) is synthesised from nicotinic acid derived from nicotinamide adenine nucleotides. Nicotinate N-methyltransferase (trigonelline synthase) activity was detected in coffee plants, but purification of this enzyme or cloning of the genes of this N-methyltransferase has not yet been reported. The degradation activity of trigonelline in coffee plants is extremely low.
Plant Physiology, 1993
In Coffea arabica leaves, the purine ring of theobromine (3,7dimethylxanthine) 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'monophosphate (IMP), sum of adenine nucleotides (ZAde), theobromine, and caffeine; and (b) incorporation of [14C]formate into IMP, ZAde, theobromine, and caffeine was inhibited by azaserine, a known inhibitor of de novo purine biosynthesis. Capacity of coffee leaves to salvage added purines was demonstrated by incorporation of [14C]hypoxanthine into ZAde and the incorporation of ["Cladenosine, [14C]adenine, ["Clinosine, and ['4C]hypoxanthine into both theobromine and caffeine. Consistent with synthesis of theobromine from two separate purine nucleotide pools, one synthesized de novo and one via salvage, added xanthine 5'-monophosphate (XMP), inosine, or hypoxanthine failed to reduce the incorporation of [14C]formate into theobromine but diluted the specific radioactivity of ["C]adenosine and [14C]adenine incorporated into theobromine. Evidence that theobromine is not the immediate precursor of caffeine is provided: (a) [14C]xanthine was incorporated into caffeine but not into theobromine; (b) exogenous xanthine diluted the specific radioactivity of caffeine synthesized from ["Cladenine and [14C]hypoxanthine but caused accumulation of radiolabel in theobromine; (c) allopurinol, a known inhibitor of the conversion of hypoxanthine to xanthine, reduced incorporation of ['%Iadenine and [14C]hypoxanthine into caffeine but caused accumulation of radiolabel in theobromine; and (d) incorporation of [14C]formate into caffeine, but not into theobromine, was reduced by added XMP, inosine, or hypoxanthine. ~~~~ ~ ~ ~ Attempts to elucidate the pathway by which theobromine (3,7-dimethylxanthine) is synthesized in Coffea arabica have been limited exclusively to studies of the metabolism of preformed nucleosides and bases or their 1-, 3-, or 7-methylated counterparts (Looser et al., 1974; Suzuki and Takahashi, 1975a; Roberts and Waller, 1979; Suzuki and Waller, 1984). The results of these studies demonstrated that radiolabeled adenine, guanine, and xanthine were incorporated into 7-methylxanthine, theobromine, and caffeine (Suzuki ~ ~ ~ ' Supported in part by a fellowship from the Graduate Division,
Distribution, biosynthesis and function of purine and pyridine alkaloids in Coffea arabica seedlings
Plant Science, 2004
Endogenous levels of purine and pyridine alkaloids were studied in different parts of 6-month-old Coffea arabica seedlings. In seedlings, caffeine was distributed mainly in leaves and cotyledons at concentrations varying from 43 to 104 mol g −1 dry weight. Essentially no caffeine was detected in roots or in older brown parts of shoots. In contrast, trigonelline was present in all parts of the seedlings. The concentration of trigonelline was highest in the upper part of the stems, including buds, which consist of young cells (180 mol g −1 dry weight), and was lowest in roots (25 mol g −1 dry weight). The trigonelline concentration in leaves was 60-80 mol g −1 dry weight, and the concentration in young leaves was higher than in older leaves. Purine alkaloid biosynthesis was estimated from the incorporation of radioactivity from [8-14 C]adenosine into purine alkaloids. Theobromine and caffeine were synthesized only in young leaves and young shoots including buds, but no biosynthetic activity was found in roots or aged cotyledons. Biosynthetic activity of trigonelline was estimated from the conversion of exogenously supplied [carboxyl-14 C]nicotinic acid to trigonelline. Trigonelline synthesis was found in all parts of the coffee seedlings. Metabolic fate studies indicated that large fractions of the radioactivity from [carboxyl-14 C]nicotinic acid (59% in leaves, 53% in cotyledons, 36% in stems and 29% in roots) were incorporated into trigonelline during a 4 h incubation period. Radioactivity was also found in NAD(P), NMN and nicotinamide. Only trace amounts of 14 CO 2 from [carboxyl-14 C] nicotinic acid were detected. These results suggest that caffeine accumulation is specific to above ground parts (leaves, cotyledons and shoots) of the seedlings and that biosynthesis is performed only in very young tissues, whereas trigonelline is distributed in all parts of coffee seedlings and biosynthetic activity is present even in mature parts. The differing roles of these two alkaloids are discussed.