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In this study, the temperature and pressure of supercritical CO

Parsley [Petroselinum crispum (Mill.) Fuss] is regarded as an aromatic, culinary, and medicinal plant and is used in the cosmetic, food, and pharmaceutical industries. However, few studies with conflicting results have been conducted on the antimicrobial activity of parsley essential oil. In addition, there have been no reports of essential oil obtained from parsley aerial parts, except seeds, as an alternative natural antimicrobial agent. Also, microorganism resistance is still a challenge for health and food production. Based on the demand for natural products to control microorganisms, and the reevaluation of potential medicinal plants for controlling diseases, the objective of this study was to determine the chemical composition and antibacterial and antifungal activities of parsley essential oil against foodborne diseases and opportunistic pathogens. Seven bacteria and eight fungi were tested. The essential oil major compounds were apiol, myristicin, and beta-phellandrene. Parsley essential oil had bacteriostatic activity against all tested bacteria, mainly Staphylococcus aureus, Listeria monocytogenes, and Salmonella enterica, at similar or lower concentrations than at least one of the controls, and bactericidal activity against all tested bacteria, mainly S. aureus, at similar or lower concentrations than at least one of the controls. This essential oil also had fungistatic activity against all tested fungi, mainly, Penicillium ochrochloron and Trichoderma viride, at lower concentrations than the ketoconazole control and fungicidal activity against all tested fungi at higher concentrations than the controls. Parsley is used in cooking and medicine, and its essential oil is an effective antimicrobial agent.

Translocation of minerals from substrate to mushrooms can change the medicinal characteristics, commercial value, and biological efficiency of mushroom. In the present study, we demonstrated that addition of iron to the substrate reduces the yield of Pleurotus ostreatus mushroom. The biological efficiency of the mushroom varied from 36.53% on the unsupplemented substrate to 2.08% for the substrate with 500 mg/kg iron added. The maximum iron concentration obtained for mushroom was 478.66 mg/kg (dry basis) and the maximum solubility in vitro was 293.70 mg/kg (dry basis). Iron translocation increased the ash and protein content, reduced antioxidant activity, and enhanced the aroma and flavor characteristics of the mushroom. However mushroom has higher amounts of iron than vegetables like collard greens, it is not feasible to use mushrooms as the only dietary source of iron. The study also indicated that because of more bioaccumulation of iron in mycelium than in the mushroom, mycelium and not mushroom, could be a better alternative as a non-animal iron source.

Following the synthesis of reference standards of the primaquine metabolites, a high-performance liquid chromatographic (HPLC) analytical method for carboxyprimaquine, its glycine conjugate, and its glucuronide conjugate in urine samples was developed. After the administration of primaquine, only trace quantities of primaquine and carboxyprimaquine (each less than 1% of dose) and no significant quantity of the two conjugates of carboxyprimaquine were excreted in the urine. When carboxyprimaquine was administered, only 0.3% of the dose was excreted in the urine. When carboxyprimaquine glycinate was administered, the compound was found in the 700- to 1300-µg/ml concentration range in the urine within the first few hours. Using (14)C-labeled primaquine, six new metabolites were found in the urine and partially characterized. The purported metabolites of primaquine (8-amino-6-methoxyquinoline, 5-hydroxyprimaquine, and 6-desmethyl-5-hydroxyprimaquine) were not found in the urine. A field screening test for the quantitation of primaquine metabolites in urine was also investigated. The inexpensive, but sensitive assay was found to give results that closely paralleled the more complex HPLC method and it was moderately well correlated with the total radioactivity in the urine samples.

The development of CYP2D6 has been attributed to the need of earth-dwelling animals to detoxify toxic xenobiotics (phytoalexins) present in plants. This hypothesis has been extrapolated to humans, but is yet unconfirmed. Therefore, we studied two Amerindian populations as the best available model to test the effect of selection through diet on human CYP2D6 evolution. The frequency of sparteine poor metabolizers in Ngawbe was 4.4% (n = 344), while the frequency in Embera was 2.2% (n = 153). Among Ngawbe and Embera, CYP2D6*4 (allelic frequencies for each tribe, respectively: 0.171; 0.14), CYP2D6*6 (0.005; 0.011) and CYP2D6*10 (0.175; 0.069) were detected, while CYP2D6*3, CYP2D6*5, CYP2D6*9 and CYP2D6*16 were absent. All poor metabolizers possessed either CYP2D6*4 or CYP2D6*6 and there were no disagreements between genotypic and phenotypic data. The total frequency of mutant alleles showed no difference among Amerindians or when compared to Caucasians. It was higher than in Chinese, since the frequency of CYP2D6*4 was higher in Amerindians. XbaI restriction fragment length polymorphisms haplotypes were very homogeneous in Amerindians, because the only fragment that hybridized with the CYP2D6 cDNA probe was the 29 kb (not 42/44 kb or 11.5/13 kb). This indicated no gene cluster recombinations that generate insertions or deletions. We propose that in earlier hominids and humans, CYP2D6 had increasingly become a vestigial characteristic unconstrained by dietary stressors, as a result of cultural survival strategies. Human CYP2D6 evolution was preferentially affected by random genetic drift, and not by adaptive or purifying selection.

Human biodiversity originates partially from human microevolution, which have produced different populations. This biodiversity is responsible for most of the variability in drug response. We present the methodology employed in population pharmacology studies and general information about the CYP2D6 and NAT2 systems. We report results obtained in Embera and Ngawbe Amerindians, who are characterized by a low phenotypic and genotypic CYP2D6 diversity. In regard to NAT2, Amerindians are distinguished by a high allelic frequency of S3 and low ones of S1 and S2, situation which is reversed in Caucasians.

We have found, in this first genetic study of a supposedly admixed Panamanian population, that the cultural group known as "cholos of Coclé" constitute a trihybrid mixture, whose genetic pool has the following composition: 44% Amerindian, 38% Caucasoid and 18% Negroid. Similarly, we have detected Amerindian genes, such as LDHB--Gua and TFchi, in proportions that relate this population with the extant Ngawbé (Guaymí). Nevertheless, the very high frequency of variant PEPA--KUN seems to indicate the genetic contribution of Amerindian populations from Eastern Panama, possibly from the extinct indigenous group cueva. This variant is frequently found among the present-day Kuna, but has not been detected among Nagawbé and Buglé.

carta al editor -- Universidad de Costa Rica. Instituto de Investigaciones en Salud. 1991 Definitions of genetic polymorphism currently employed in the pharmacological literature have been incorrectly used (Kalow, 1984) and uncritically imported from population genetics [e.g., Weinshilboum (1984), Evans (1977)], apparently without regard to the problems their application might present in pharmacogenetics or, more specifically, in pharmacogenetic studies of populations. Universidad de Costa Rica. Instituto de Investigaciones en Salud UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA)

We report on studies of the oxidative routes associated with the polymorphic metabolism of debrisoquine, sparteine and mephenytoin, as well as on the pathway catalyzed by N-acetyl-transferase. Normal, healthy non-related subjects were studied: 250 Cuna, 285 Ngawbé Guaymí and 20 Teribe. These studies were aimed at establishing differences or similarities among Amerindian tribes and between them and Caucasians, since certain abnormal or non-expected results in clinical response to drugs could be due to racial differences. In those cases, it was considered necessary to evaluate the degree of toxicity and danger of drugs administration, and their effective therapeutic actions.

Artículo científico -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 1988 Sparteine sulfate (50 mg) was administered to 170 Cuna Amerindians, 142 of whom were unrelated, and the drug and its dehydrometabolites were determined in the 0- to 12-hour urine samples. The log10 of the metabolic ratio was unimodally, but not normally, distributed and showed the following values: mean 0.21 ± 0.26, median 0.24, limits 0.73 and 0.76, skewness 1.00, and kurtosis 4.95. On the basis of these results, it can be concluded that there are no deficient metabolizers in the Cuna sample population studied. However, the similarity of the skewness found between the Cuna sample population studied and the extensive Canadian white group, as well as an inflection point at 6.3 U in the former's probit plot, suggests the existence of at least two subgroups congregating within the same single mode in the frequency distribution curve. The use of the inflection point is discussed thoroughly, concluding that although it does not allow exclusion of the existence of genotypically different subgroups, the limitations of the data do not permit its use to determine the number of heterozygotes and thus the existence of polymorphism. The possibility of an isozyme variant, consistent with the general genetic structure of Amerindians, as suggested by the coexistence of two subgroups within the unimodal curve, is entertained. (CLIN PHARmAcoL THER 1988;43:456-65.) Universidad de Costa Rica. Instituto de Investigaciones en Salud. Universidad de Panamá Universidad de Toronto UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto de Investigaciones en Salud (INISA)

The oxidation of sparteine was studied in a total of 121 Ngawbe Guaymi volunteers in Panama, 97 of whom were unrelated. When presented in a frequency histogram, the results of the log10 of the metabolic ratios (LMR) indicated the existence of two modes, the largest of which exhibited a normal distribution (α = 0.05; χ2 = 5.46). A preliminary assignment of an antimode for this population sample is proposed, located within the region of LMR 0.65 to 0.85 vs LMR of 1.3 for white subjects, and results in five poor metabolizers (PMs) (5.2%). This is in contrast to the absence of PMs (0/210) we have reported for the Cuna Amerindians. The microevolution of the sparteine route, corresponding to a tenfold change in the frequency of PMs, is likely to have occurred within their genetic divergence time. These observations of the divergence of a metabolic route of therapeutic importance and the proposal of a time frame for its microevolution constitute the first cases in the literature. Clinical Pharmacology and Therapeutics (1988) 44, 343–352; doi:10.1038/clpt.1988.160