Partial sequences of the gene that codifies for the transcription factor VPHSFB1 in Vasconcellea pubescens: First report / Secuencias parciales del gen que codifica para el factor de transcripción VPHSFB1 en Vasconcellea pubescens: Primer reporte

Plant heat stress transcription factors (HSFs) are involved in the response to heat. In Arabidopsis thaliana the HSFs genes are completely identified, however there was no information available about these genes in Vasconcellea pubescens (Chamburo) until now. In this preliminary work we describe the VPHSFB1 gene of V. pubescens (gene expression evaluated by RT-PCR and the partial sequence) that was induced by the increment of temperature. From our results, VPHSFB1 could be used as a heat response marker gene in tropical species.

Los factores de transcripción del estrés por calor en plantas (HSFs) están involucrados en la respuesta al calor. En Arabidopsis thaliana los genes HSFs están completamente identificados, sin embargo no había información disponible sobre estos genes en Vasconcellea pubescens (Chamburo) hasta ahora. En este trabajo preliminar describimos el gen VPHSFB1 de V. pubescens (expresión génica evaluada por RT-PCR y la secuencia parcial) que fue inducido por el incremento de temperatura. A partir de nuestros resultados, se podría usar a VPHSFB1 como un gen marcador de respuesta a calor en especies tropicales.

Identification and quantification of flavonoids in Carica papaya leaf and peroxynitrite-scavenging activity

Objective To characterize the types, contents, and peroxynitrite-scavenging activities of flavonoids in the leaf of Carica papaya (C. papaya). Methods Chromatographic and spectroscopic techniques along with high performance liquid chromatography quantitative analysis and peroxynitrite-scavenging assay were performed to isolate and quantify flavonoid compounds in the flavonoid-rich fraction (BuOH fraction) derived from MeOH extract of C. papaya leaves and evaluate their peroxynitrite-scavenging activities. Results Seven flavonoids were isolated from the leaves of C. papaya, including quercetin 3-(2

Identification and quantification of flavonoids in Carica papaya leaf and peroxynitrite-scavenging activity

Objective: To characterize the types, contents, and peroxynitrite-scavenging activities of flavonoids in the leaf of Carica papaya (C. papaya). Methods: Chromatographic and spectroscopic techniques along with high performance liquid chromatography quantitative analysis and peroxynitrite-scavenging assay were performed to isolate and quantify flavonoid compounds in the flavonoid-rich fraction (BuOH fraction) derived from MeOH extract of C. papaya leaves and evaluate their peroxynitrite-scavenging activities. Results: Seven flavonoids were isolated from the leaves of C. papaya, including quer-cetin 3-(2G-rhamnosylrutinoside), kaempferol 3-(2G-rhamnosylrutinoside), quercetin 3-rutinoside, myricetin 3-rhamnoside, kaempferol 3-rutinoside, quercetin, and kaemp-ferol. All of the substances exhibited potent activities on peroxynitrite scavenging (IC50 ≤ 4.15 μmol/L), which were stronger than the positive control, L-penicillamine (6.90μmol/L). The content of kaempferol 3-(2G-rhamnosylrutinoside) was significantly higher than other identified compounds (123.18 mg/g BuOH fraction and 7.23 mg/g MeOH extract). Conclusions: The results of the present study demonstrate the potent antioxidant fla-vonoids of C. papaya leaf, with kaempferol 3-(2G-rhamnosylrutinoside) as the major one.

Biodistribution, pharmacokinetics and toxicity of a Vasconcellea cundinamarcensis proteinase fraction with pharmacological activity

Abstract Prior studies demonstrate that a proteinase fraction from Vasconcellea cundinamarcensis V.M. Badillo, Caricaceae, exhibits wound healing activity in gastric and cutaneous models and antitumoral/antimetastatic effects. Here, we present the toxicity, pharmacokinetics and biodistribution data for this proteinase fraction following a single dose into Swiss mice by i.v., s.c. or p.o. routes. The i.v. and s.c. toxicity assays demonstrate that proteinase fraction at ≤20 mg/kg is non-lethal after single injection, while parental administration (p.o.) of ≤300 mg/kg does not cause death. Based on p.o. acute toxicity dose using Organisation for Economic Cooperation and Development protocols, proteinase fraction ranks as Class IV “harmful” substance. Proteinase fraction shows high uptake determined as Kp (distribution tissue/blood) in organs linked to metabolism and excretion. Also, high bioavailability (≈100%) was observed by s.c. administration. The blood contents following i.v. dose fits into a pharmacokinetic bi-compartmental model, consisting of high removal constants – kel 0.22 h−1 and kd 2.32 h−1and a half-life – t½ = 3.13 h. The Ames test of proteinase fraction (0.01–1%) demonstrates absence of mutagenic activity. Likewise, genotoxic evaluation of proteinase fraction (5 or 10 mg/kg, i.p.) shows no influence in micronuclei frequency. In conclusion, the acute doses for proteinase fraction lack mutagenic and genotoxic activity, clearing the way for clinical assays.

Genetic diversity and structure of wild populations of the tropical dry forest tree Jacaratia Mexicana (Brassicales: Caricaceae) at a local scale in Mexico

The tropical dry forest is a greatly endangered ecosystem, from which Jacaratia mexicana is a native tree. With the aim to assess the levels of genetic variation and population structure, four wild populations of J. mexicana were studied in the Sierra de Huautla Biosphere Reserve, Morelos, Mexico. For this, DNA was extracted from 159 individuals and were amplified with six random primers using the Random Amplified Polymorphic DNA (RAPD). A total of 54 bands were obtained, of which 50 (92.6%) were polymorphic. The total genetic diversity found within the four populations was 0.451 when estimated by Shannon’s index. An AMOVA analysis showed that 84% of the total genetic variation was found within populations and 16% was among populations. The UPGMA dendrogram showed that all individuals from one of the populations (Huaxtla) formed one distinct genetic group, while the rest of the individuals did not cluster according to population. A Mantel test did not show an association between genetic and geographical distances among populations (r=0.893, p=0.20). A Bayesian cluster analysis performed with STRUCTURE, showed that the most probable number of genetic groups in the data was four (K=4), and confirmed the distinctness of Huaxtla population. Our results showed that important genetic differentiation among populations can occur even at this small geographic scale and this has to be considered in conservation actions for this genetic resource.

Jacaratia mexicana es un árbol nativo del bosque tropical seco, que es considerado el tipo de vegetación en mayor riesgo de desaparecer completamente. Se utilizaron polimorfismos de ADN amplificados al azar (RAPD, Random Amplified Polymorphic DNA), para evaluar los niveles de variación y estructura genética en cuatro poblaciones silvestres de J. mexicana en la Reserva de la Biósfera Sierra de Huautla (Morelos, México). Se amplificó el ADN de 159 individuos utilizando seis oligonucleótidos (“primers”) aleatorios. Se obtuvieron en total 54 bandas, de las cuales 50 (92.6%) fueron polimórficas. La diversidad genética total que se encontró en las cuatro poblaciones de J. mexicana fue de 0.451 de acuerdo con el índice de Shannon. Un análisis de varianza molecular (AMOVA) mostró que el 84% de la variación genética total se encuentra dentro de las poblaciones y el 16% entre las poblaciones. Un dendrograma construido mediante el algoritmo UPGMA mostró que los individuos de una población (Huaxtla) formaron un grupo, mientras que el resto de los individuos no se agruparon de acuerdo a su población de origen. Una prueba de Mantel no mostró una asociación entre las distancias genéticas y geográficas entre las poblaciones (r=0.893, p=0.20). Un análisis de agrupamiento Bayesiano realizado mediante STRUCTURE mostró que el número más probable de grupos genéticos es cuatro (K=4) y confirmó la diferenciación de la población Huaxtla. Nuestros resultados muestran que una considerable diferenciación genética entre poblaciones puede existir incluso a esta escala geográfica, lo cual es de interés para la conservación de este recurso genético.