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At least 19 recordsLinked to original sources
PubMed1998

Herbicide residues in leaves of Erythroxylum coca var. coca plants treated with soil-applied tebuthiuron and hexazinone.

The herbicide residue levels in leaves of Erythroxylum coca var. coca Lam. plants treated with soil applications of tebuthiuron and hexazinone at 3.36 and 6.72 kg a.i. ha-1 were determined in order to estimate the potential for human exposure to these residues from consuming the leaves or cocaine produced from them. Field-grown plants were treated with a commercial formulation of tebuthiuron or hexazinone and leaves were harvested at the first indication of herbicide injury (i.e. chlorosis and/or necrosis) and at the onset of leaf abscission. Herbicide residues were detected by HPLC in leaf samples from both harvests of all plants treated with tebuthiuron or hexazinone. At 3.36 kg ha-1, herbicide residues in the leaves were less than 2 micrograms g-1 dry wt. for both harvests of both experiments. The highest residue levels detected were 5.90 micrograms g-1 dry wt. for tebuthiuron and 7.17 micrograms g-1 dry wt. for hexazinone in leaves from plants treated with the herbicide at the rate of 6.72 kg ha-1 and harvested at the onset of leaf drop. Based on published toxicity data and estimates of leaf consumption, the herbicide residues in leaves of E. coca var. coca plants treated with tebuthiuron or hexazinone at twice the recommended control rates or less would have a negligible contribution to the health risks of individuals who chew coca leaves. Furthermore, based on the most conservative estimates of cocaine yield and herbicide carry over, death by cocaine overdose would occur long before the NOEL for either herbicide was reached.

Cacao↗
PubMed1997

A study of the chemical composition of Erythroxylum coca var. coca leaves collected in two ecological regions of Bolivia.

Coca-Erythroxylum coca Lamarck var. coca-remains one of the most common plants of the folk medicine of Bolivia used as a general stimulant. Aymara and Quechua natives prefer to chew the sweeter coca leaves from the Yungas (tropical mountain forests of the eastern slopes of the Andes) rather than those from the Chapare lowlands. The contents in cocaine and minor constituents of leaf samples cultivated in these regions does not rationalize this choice.

Bolivia↗
PubMed1984

Local anesthetic effects of cocaine and several extracts of the coca leaf (E. coca).

Cocaine and a number of different fractions of a crude ethanol extract of the coca leaf (E. coca) were subjected to a local anesthetic screen using rat tail withdrawal from electric shock. Following an intradermal injection of 0.1 ml of a 2.0% (w.v) solution of cocaine HCl, an immediate response was observed. Two of the coca fractions also produced some local anesthesia. An alkaloidal fraction, containing an equivalent amount of cocaine, produced a maximum effect that was approximately 20% less than that observed with cocaine. The only other fraction producing any effect, a water soluble cocaine-free fraction, showed a maximum response that was approximately 30% of that observed with cocaine.

Anesthetics, Local↗
PubMedDate not supplied

Constituents of Erythroxylon coca. II. Gas-chromatographic analysis of cocaine and other alkaloids in coca leaves.

A gas-chromatographic procedure is outlined for the analysis of cocaine and cis- and trans-cinnamoylcocaines in coca leaves. The procedure was applied to the determination of these alkaloids in coca leaves collected from three different locations in Peru. The extraction of alkaloids from plant material was accomplished following the procedure we previously outlined. Recovery of cinnamoylcocaines was quantitative and the average coefficient of variation was 6.8%. Using androst-4-ene-3,17-dione as the internal standard, the correlation coefficient (r2) as determined from the calibration curve of trans-cinnamoylcocaine was 0.99 and the response factor 0.72. Observable differences in relative proportions of cis and trans isomers of cinnamoylcocaine were found among samples from different locations. In addition, the relative proportions of the total cinnamoylcocaine concentration to cocaine varied with sample origin. We have also examined coca extracts using a nitrogen detector and by gas chromatography--mass spectrometry. The nature and identity of other nitrogenous peaks in the chromatograms are also discussed.

Alkaloids↗
PubMed1997

(H)N(COCA)NH and HN(COCA)NH experiments for 1H-15N backbone assignments in 13C/15N-labeled proteins.

Triple resonance HN(COCA)NH pulse sequences for correlating 1H(i), 15N(i), 1H(i-1), and 15N(i-1) spins that utilize overlapping coherence transfer periods provide increased sensitivity relative to pulse sequences that utilize sequential coherence transfer periods. Although the overlapping sequence elements reduce the overall duration of the pulse sequences, the principal benefit derives from a reduction in the number of 180 degrees pulses. Two versions of the technique are presented: a 3D (H)N(COCA)NH experiment that correlates 15N(i), 1H(i-1), and 15N(i-1) spins, and a 3D HN(COCA)NH experiment that correlates 1H(i), 15N(i), 1H(i-1), and 15N(i-1) spins by simultaneously encoding the 1H(i) and 15N(i) chemical shifts during the t1 evolution period. The methods are demonstrated on a 13C/15N-enriched sample of the protein ubiquitin and are easily adapted for application to 2H/13C/15N-enriched proteins.

Carbon Isotopes↗
PubMed2005

Alkaloid content of the seeds from Erythroxylum Coca var. Coca.

Alkaloid extracts from the seeds of Erythroxylum Coca var. Coca grown in the Chapare Valley of Bolivia were subjected to gas and liquid chromatographic-mass spectrometric analyses. Several alkaloids from these seeds were detected and characterized, including methylecgonidine, tropine, 3alpha-acetoxytropane, ecgonine methyl ester, cuscohygrine, N-norbenzoyltropine, benzoyltropine, hexanoylecgonine methyl ester, cocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine. Methylecgonidine was determined to be the primary constituent and not an analytical artifact. Additionally, two significant new uncharacterized alkaloids were established as present. Recent evidence suggests that some cocaine processors are adding this seed extraction material to cocaine extracted from coca leaf and may impact cocaine impurity signature profiles.

Alkaloids↗
PubMed1981

Comparative stimulus properties of two fractions of the coca leaf (E. coca).

Male and female Wistar rats were trained to discriminate 5.0 mg/kg cocaine from 2.0 ml/kg saline using a two-bar food reinforcement (FR 30) drug discrimination paradigm. Once discrimination behavior had stabilized the subjects were tested (in extinction) with several doses of two different fractions of the coca leaf and four doses of cocaine HCl (1.0, 2.5, 7.5, 10 mg/kg). The fractions were prepared by extracting powdered coca leaves with 95% ethanol and then partitioning the residue between chloroform and water. Two doses of the water fractions (480, 960 mg/kg) and five doses of the chloroform fraction (7.5, 15, 30, 60 120 mg/kg) were tested. The water fractions was devoid of cocaine while the five doses of the chloroform fraction contained cocaine equivalent to 0.4, 0.83, 1.65, 3.3 and 6.6 mg/kg, respectively, as determined by gas chromatographic analysis. The 2.5, 7.5, and 10.0 mg/kg cocaine doses generalized to cocaine. The 1.0 mg/kg dose of cocaine generalized to saline. The water fraction at 480 mg/kg generalized to saline; however following pretreatment with the 960 mg/kg dose of this fraction, the animals failed to respond. The two largest doses of the chloroform fraction (60 and 120 mg/kg) generalized to cocaine while the other three doses did not. The 7.5 mg/kg generalized to saline; the 15 and 30 mg/kg doses engendered an intermediate level of responding on both the cocaine and saline lever.

Animals↗
PubMed2005

Antiquity of coca-leaf chewing in the south central Andes: a 3,000 year archaeological record of coca-leaf chewing from northern Chile.

Carbon-14 (14C) dating from mummies of the Alto Ramirez culture confirms that coca leaf chewing was an incipient practice among members of a population that peopled the valleys and coastal areas of Northern Chile by 3,000 years before the present (yr.B.P.). Out of eleven bodies from the burial site of Pisagua-7 (PSG-7, S 19 degrees 35', W 70 degrees 13') that were analyzed, two samples tested positive. Mummy 725-A C2 (dated 3,090 to 2,850 two sigma calibrated 14C years before the present) was shown to have a cocaine value of 13.3 nanograms/10 milligrams of sample (ng/10mg), and mummy 741 (2,890 to 2,760 two sigma cal yr B.P.), a 5.6 ng/10mg value.

Carbon Isotopes↗
PubMed1996

Identification and quantitation of alkaloids in coca tea.

The consumption of coca tea is a common occurrence in many South American countries. The tea is often packaged in individual servings as tea bags which contain approximately 1 g of plant material. The consumption of coca tea leads to ingestion of cocaine and other alkaloids; however, there is little information available regarding the pharmacological or toxicological effects that result from consumption of coca tea. We performed a series of studies with coca tea bags from two South American countries, Peru and Bolivia. The alkaloidal content of the 'coca leaf' in coca tea bags was determined by two different extraction methods: Soxhlet extraction with methanol (exhaustive extraction), and mechanical agitation with methanol. Extracts were purified by solid-phase extraction (SPE) followed by analysis by gas chromatography/mass spectrometry (GC/MS). Coca tea prepared from Peruvian and Bolivian coca tea bags was also analyzed by SPE-GC/MS assay. In addition, urine specimens were analyzed from an individual who consumed one cup of Peruvian coca tea and one cup of Bolivian coca tea on separate occasions. Urine samples were analyzed by immunoassay (TDx) and SPE-GC/MS. Analysis of coca tea bags and coca tea indicated that cocaine, benzoylecgonine, ecgonine methyl ester and trans-cinnamoylcocaine were present in varying quantities. With exhaustive extraction, an average of 5.11 mg, and 4.86 mg of cocaine per tea bag were found in coca leaf from Peru and Bolivia, respectively. The average amounts of benzoylecgonine, ecgonine methyl ester in Peruvian coca leaf were 0.11 and 1.15 mg, and in Bolivian coca leaf were 0.12 and 2.93 mg per tea bag, respectively. trans-cinnamoylcocaine was found in trace amounts in Peruvian tea bags and 0.16 mg/tea bag of Bolivian tea. When tea was prepared, an average of 4.14 mg of cocaine was present in a cup of Peruvian coca tea and 4.29 mg of cocaine was present in Bolivian tea. Following the consumption of a cup of Peruvian tea by one individual, a peak urine benzoylecgonine concentration of 3940 ng/ml occurred 10 h after ingestion. Consumption of Bolivian coca tea resulted in a peak benzoylecgonine concentration of 4979 ng/ml at 3.5 h. The cumulative urinary excretion of benzoylecgonine after approximately 48 h, determined by GC/MS, was 3.11 mg and 2.69 mg after consumption of Peruvian and Bolivian coca tea, respectively. This study demonstrated that coca tea bags and coca tea contain a significant amount of cocaine and cocaine-related alkaloids and the consumption of a single cup of Peruvian or Bolivian coca tea produces positive drug test results for cocaine metabolites.

Alkaloids↗
PubMedDate not supplied

Systematic anatomy of Erythroxylum P. Browne: practical and evolutionary implications for the cultivated cocas.

Preliminary study of the pantropical Erythroxylaceae indicates that anatomical features can provide valuable insight into the generic, infra-generic and specific affinities of unidentified specimens. Combinations of qualitative and quantitative anatomical data are most reliable when considered in conjunction with relevant ecological and plant morphological data. Extreme caution is advised in such taxonomic applications due to the intergrading patterns of anatomical variation exhibited within the family. Careful consideration must be given to the potential influence on anatomy of factors such as plant age, habit, leaf morphology and environmental conditions. Although a few species of Erythroxylum are identifiable solely on the basis of unique wood anatomical features, the majority of species can be identified only through a combination of morphological and vegetative anatomical features. Closely related species and species of similar habitats are often very similar in their wood and leaf structure. Anatomical differences are more subtle among the cultivated cocas and their closest neotropical relatives than among most taxa of Erythroxylaceae. A typological concept of foliar venation patterns among the cultivated cocas permits the varietal identification of isolated coca leaves. Several neotropical relatives of the cultivated cocas represent potential adulterants in commercial samples of coca leaf as a result of their striking similarity to genuine coca in leaf form, venation and anatomy. Due to the broad and overlapping range of leaf structural variation exhibited among the cultivated cocas and their nearest relatives, identifications of isolated leaves or leaf fragments are ill-advised in the absence of relevant ecological data. Patterns of wood and leaf anatomical variation within the Erythroxylaceae are most readily explicable as the result of evolutionary diversification in plant habit, leaf size, form and relative duration. Significant correlations among wood and leaf structure reveal various "adaptive strategies" among species of Erythroxylaceae. Redundant patterns of structural evolution, evident among the different species and genera of Erythroxylaceae, help to elucidate the probable evolutionary origins of the cultivated cocas. Comparative anatomical data support the hypothesis that Bolivian coca (E. coca) represents the most primitive of the cultivated cocas. The Colombian and Trujillo varieties of coca (E. novogranatense) appear to have been derived from a Bolivian-like ancestral coca as a result of long-term cultivation, geographic isolation and human selection for increased flavor, palatability and drought resistance.

Coca↗
PubMed1997

Fluid regulatory hormone response to exercise after coca-induced body fluid shifts.

To determine the effect of coca chewing on heart rate (HR), mean arterial blood pressure (MAP), and plasma volume and their relationship with the hormones regulating cardiovascular and body fluid homeostasis, 16 male volunteers were examined at rest and during 1 h of cycle exercise at approximately 75% of their peak oxygen uptake in two trials separated by 1 mo. One trial was performed after the subjects chewed a sugar-free chewing gum (Coca- trial), whereas the other was done after the subjects chewed 15 g of coca leaves (Coca+), with the order of the Coca- and Coca+ trials being randomized. Blood samples were taken at rest, before (R1) and after 1-h chewing (R2), and during the 5th, 15th, 30th, and 60th min of exercise. They were analyzed for hematocrit, hemoglobin concentration, red blood cell count, plasma proteins, and for the fluid regulatory hormones, including plasma catecholamines [norepinephrine (NE) and epinephrine], renin, arginine vasopressin, and the atrial natriuretic peptide (ANP). During the control trial (Coca-), from R1 to R2, there was no significant change in hematologic, hormonal, and cardiovascular status except for a small increase in plasma NE. In contrast, it can be calculated that coca chewing at rest induced a significant hemoconcentration (-3.8 +/- 1. 3% in blood and -7.0 +/- 0.7% in plasma volume), increased NE and MAP, and reduced plasma ANP. Chewing coca before exercise reduced the body fluid shifts but enhanced HR response during exercise. These effects were not accompanied by changes in NE, epinephrine, renin, and arginine vasopressin plasma levels. In contrast, plasma ANP response to exercise was lower during the Coca+ trial, suggesting that central cardiac filling was reduced by coca use. It is likely that the reduction in body fluid volumes is a major contributing factor to the higher HR at any given time of exercise after coca chewing.

Adult↗
PubMed1996

Coca chewing for exercise: hormonal and metabolic responses of nonhabitual chewers.

To determine the effects of acute coca use on the hormonal and metabolic responses to exercise, 12 healthy nonhabitual coca users were submitted twice to steady-state exercise (approximately 75% maximal O2 uptake). On one occasion, they were asked to chew 15 g of coca leaves 1 h before exercise, whereas on the other occasion, exercise was performed after 1 h of chewing a sugar-free chewing gum. Plasma epinephrine, norepinephrine, insulin, glucagon, and metabolites (glucose, lactate, glycerol, and free fatty acids) were determined at rest before and after coca chewing and during the 5th, 15th, 30th, and 60th min of exercise. Simultaneously to these determinations, cardiorespiratory variables (heart rate, mean arterial blood pressure, oxygen uptake, and respiratory gas exchange ratio) were also measured. At rest, coca chewing had no effect on plasma hormonal and metabolic levels except for a significantly reduced insulin concentration. During exercise, the oxygen uptake, heart rate, and respiratory gas exchange ratio were significantly increased in the coca-chewing trial compared with the control (gum-chewing) test. The exercise-induced drop in plasma glucose and insulin was prevented by prior coca chewing. These results contrast with previous data obtained in chronic coca users who display during prolonged submaximal exercise an exaggerated plasma sympathetic response, an enhanced availability and utilization of fat (R. Favier, E. Caceres, H. Koubi, B. Sempore, M. Sauvain, and H. Spielvogel. J. Appl. Physiol. 80: 650-655, 1996). We conclude that, whereas coca chewing might affect glucose homeostasis during exercise, none of the physiological data provided by this study would suggest that acute coca chewing in nonhabitual users could enhance tolerance to exercise.

Adult↗
PubMed1997

Body fluid homeostasis and cardiovascular adjustments during submaximal exercise: influence of chewing coca leaves.

The present study was undertaken to determine the haematological and cardiovascular status, at rest and during prolonged (1h) submaximal exercise (approximately 70% of peak oxygen uptake) in a group (n = 12) of chronic coca users after chewing approximately 50 g of coca leaves. The results were compared to those obtained in a group (n = 12) of nonchewers. At rest, coca chewing was accompanied by a significant increase in heart rate [from 60 (SEM 4) TO 76 (SEM 3) beats.min-1], in haematocrit [from 53.2 (SEM 1.2) to 55.6 (SEM 1.1)%] in haemoglobin concentration, and plasma noradrenaline concentration [from 2.8 (SEM 0.4) to 5.0 (SEM 0.5) mumol.l-1]. It was calculated that coca chewing for 1 h resulted in a significant decrease in blood [-4.3 (SEM 2.2)%] and plasma [-8.7 (SEM 1.2)%] volume. During submaximal exercise, coca chewers displayed a significantly higher heart rate and mean arterial blood pressure. The exercise-induced haemoconcentration was blunted in coca chewers compared to nonchewers. It was concluded that the coca-induced fluid shift observed at rest in these coca chewers was not cumulative with that of exercise, and that the hypovolaemia induced by coca chewing at rest compromised circulatory adjustments during exercise.

Adolescent↗
PubMed1994

Determination and in-depth chromatographic analyses of alkaloids in South American and greenhouse-cultivated coca leaves.

Methodology is described for the detection and/or determination of cocaine and minor alkaloids in South American coca as well as in greenhouse- and tropical-cultivated field coca of known taxonomy. Coca leaf from Bolivia, Peru, Ecuador and Colombia were subjected to the determination of cocaine, cis- and trans-cinnamoylcocaine, tropacocaine, hygrine, cuscohygrine and the isomeric truxillines. The greenhouse samples were cocaine-bearing leaves of the genus Erythroxylum and included E. coca var. coca, E. novogranatense var. novogranatense and E. novogranatense var. truxillense, and the alkaloids determined were cocaine, ecgonine methyl ester, cuscohygrine, tropacocaine and the cinnamoylcocaines. The tropical-cultivated coca were E. novogranatense var. novogranatense and E. coca var. coca. Cocaine and minor alkaloids were isolated from basified powdered leaf samples using a toluene extractant, followed by acid-Celite column chromatography. The isolated alkaloids were determined by capillary gas chromatography with flame ionization or electron-capture detection. Methodology is also presented for the isolation and mass spectral analysis of numerous trace-level coca alkaloids of unknown structure.

Alkaloids↗