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Selenium has been determined in different parts of the Lecythis ollaria (LO) plant (Venezuela) and the determination of its speciation has been achieved in fruit seeds. The study has been performed using different analytical techniques including inductively coupled plasma atomic emission spectrometry (ICP-AES), differential pulse cathodic stripping voltammetry (DPCSV), instrumental neutron activation analysis (INAA), high performance liquid chromatography (HPLC) and mass spectrometry (MS). Different parts of the plant (leaves, bark, capsules and seeds) were examined as well as the soil where LO was growing. Among different considered parts, seeds show the highest content in selenium (≅5 g kg −1 ) which is dependent on the maturation extent of the fruit. In seeds, about half of the total selenium content is soluble in water while the remaining is involved in protein structure. In the aqueous fraction, the prevailing form of selenium appears to be seleno-cystathionine with much lower amounts of Se(VI) and Se(IV).

Two previously healthy women developed nausea, vomiting, headache and dizziness for several days, a massive hair loss about 2 weeks later and a discoloration of the fingernails. Detailed diagnostic procedures did not reveal any pathological results. Therapeutic measures did not show any effect. Thallium and arsenic were within normal range in plasma. Delayed quantitative determination of selenium in blood, however revealed toxic values (in case I: 479 microg/L of serum, 8 weeks after ingestion, and in case II 300 microg/L of serum, 9 weeks after ingestion). In retrospect, a relation to the ingestion of paradise nuts could be established. peerReviewed

Summary High selenium concentrations (7-12 g/kg dry mass) were found in the seeds of the selenium-accumulator plant coco de mono (Lecythis ollaria). In order to obtain information on the protein-bound part of selenium in extracts of these seeds, dialysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used combined with neutron activation analysis. Extractions were carried out at pH 4.5 and 7.5. In both cases about 90 % of the element was dissolved. Of the extracted selenium only 9 % was shown to be firmly bound to proteins at pH 4.5 and 29 r% at pH 7.5. For the protein-bound selenium, concentrations of 0.7 g and 2.4 g per kg of seeds and 40 and 25 g per kg of extractable protein were determined at pH 4.5 and 7.5, respectively. By analyzing the protein fractions separated by SDS-PAGE the element was found to be present in extremely selenium-rich proteins with molecular masses below 20 kDa.

Selenium is a micronutrient. It presents a nutritional conundrum because of its twin status as an essential as well as a highly toxic trace element. Here, we report a case of acute non-intentional selenium toxicity due to increased ingestion of “paradise nuts” (Lecythis ollaria) which resulted in massive alopecia.

The observations of clinical cases of temporary alopecia(defluvium capillorum) after the ingestion of “coco de mono” nuts(Lecythis ollaria), associated with symptomatology of acute intoxication, fever and diarrhea and various neurological manifestations, preceded the experimental study of the active principle contained in these seeds. The marked cytotoxic effect of “coco de mono” has been determinedin vitro in mice flbroblasts; the active principle has been isolated and has been identified as the selenium analog of the sulfur amino acid, cystathionine. This discovery has led to great interest in the mechanism of inhibition of mitosis by the amino acid, to the experimental study of its toxicity and finally to the study of selenium found in the ground of different parts of Venezuela as well as in different pastures and cultivated areas. The implications are obvious, not only from the public health point of view but also for the country–s economy, since these studies can provide the basis for condemning for agricultural purposes vast zones of Venezuela flat lands.