Phytochemical Screening of Callus and Cell Suspensions Cultures of Thevetia peruviana

Abstract Thevetia peruviana is an ornamental shrub grown-up in many tropical region of the world. This plant produces secondary metabolites with biological properties of interest for the pharmaceutical industry. The objective was to determine the secondary metabolites profile of callus and cell suspension cultures of T. peruviana and compare them with those from explant (fruit pulp). Extracts in 50% aqueous ethanol and ethyl acetate were prepared. The phytochemical analysis was performed using standard chemical tests and thin layer chromatography. In addition, total phenolic and flavonoids compounds (TPC and TFC), total cardiac glycosides (TCG) and total antioxidant activity (TAA) was determined during the cell suspension growth. Phenolic chemical profile was also analyzed by high performance liquid chromatography (HPLC). Common metabolites (alkaloids, amino acids, antioxidants, cardiac glycosides, leucoanthocyanidins, flavonoids, phenols, sugars and triterpenes) were detected in all samples. The maximum production of extracellular TCG, TPC, TFC and TAA in cells suspensions were at 6-12 days; in contrast, intracellular content was relatively constant during the exponential grown phase (0 to 12-days). HPLC analysis detected one compound with retention time at 11.6 min; this compound was tentatively identified as dihydroquercetin, a flavonoid with anti-cancer properties. These results provide evidence on the utility of the in vitro cell cultures of T. peruviana for valuable pharmaceutical compounds production.

EVALUACIÓN DE LA RESPUESTA DE CULTIVOS CELULARES DE (Fouquieria splendens ssp. breviflora) fouquieriaceae BAJO ESTRES HÍDRICO / Assessment of (Fouquieria splendens ssp. breviflora) Cell Cultures Response Under Water Stress

RESUMEN Los cultivos de células vegetales son sistemas experimentales homogéneos altamente controlables que permiten el estudio de adaptaciones bajo condiciones de estrés hídrico, sin la interferencia de los diferentes tejidos y estados del desarrollo vegetal. Una aproximación para comprender esas adaptaciones, es la aparición de proteínas inducidas, resultado de la alteración en la expresión génica. El presente trabajo analizó la respuesta de cultivos de células de Fouquieria splendens ssp. breviflora, expuestos a ácido abscísico (ABA), mediante la caracterización electroforética en cantidad y calidad de las proteínas inducibles de estrés. Se registraron polipéptidos de bajo peso molecular (< 35kDa), comunes bajo la exposición a 10 mM, seguida la asociación con 20 y 30 mM de ABA, quedando aislada la respuesta de la condición de células en cultivo sin la presencia de éste.

ABSTRACT Plant cell cultures are homogenous experimental systems, highly controllable that allow the study of short and large water stress adaptations without the interference of the different tissues and development ofplants. An approach to understand these adaptations is through the presence of induced proteins; as a result of changes in genetic expression. This work analyze the response of Fouquieria splendens ssp. breviflora cell cultures exposed to abscisic acid (ABA), through the electrophoretic characterization of quantity and quality of stress induced proteins. There were recorded low molecular weight polypeptides (< 35kDa), common in experiments under ABA 10mM, followed by the association with 20 and 30mM ABA conditions, with a particularly response of cell cultures without the stress agent.

Citotoxicidad in vitro de extractos laticiferos de Calotropis procera (Aiton) W.T. Aiton y Pedilanthus tithymaloides (L.) Poit / In vitro cytotoxicity of laticifers extracts from Calotropis procera (Aiton) WT and Pedilanthus tithymaloides (L) Poit

In order to assess the anticancer action of extracts obtained by latex from Calotropis procera and Pedilanthus tithymaloides, samples were collected from adult plants. Soluble proteins were extracted with 16 uL of 50 mM sodium acetate pH 5/ug integral latex and centrifugation at 16,000 x g for 15 min, the supernatant was named "latex crude extract" (LCE). The "latex methanolic extract" (LME) was obtained on dried latex. Both extracts were tested in vitro by cytotoxic and cytostatic activity in Jurkat cell cultures. Cellular viability, proliferation, necrosis and apoptosis were evaluated. LCE and LME of C. procera were found with cytotoxic and cytostatic activity after 24 incubation hours (p < 0,05) with doses from 1ug/mL. The LCE and LME of P. tithymaloides presented cytotoxic effect (p < 0,05) from 50 ug/mL and from 1ug/mL, respectively.

Con el objetivo de evaluar el potencial anticanceroso de extractos de látex de Calotropis procera y Pedilanthus tithymaloides se colectaron muestras de plantas adultas. Las proteínas solubles fueron extraídas con 16 uL de acetato de sodio 50 mM pH 5/ug de látex integral y centrifugación a 16.000 x g durante 15 min, denominándose al sobrenadante “extracto crudo de látex” (ECL). El “extracto metanólico de látex” (EML) se obtuvo sobre látex deshidratado. Ambos extractos fueron probados en su actividad citotóxica y citostática in vitro sobre cultivos de células Jurkat. Se realizaron estudios de viabilidad, proliferación, necrosis y apoptosis celular. El ECL y el EML de C. procera presentaron actividad citotóxica y citostática después de 24 y 48 horas de incubación (p < 0,05) con dosis desde 1 ug/mL. Los ECL y EML de P. tithymaloides presentaron efectos citotóxicos (p < 0,05) a partir de 50 ug/mL y desde 1 ug/mL respectivamente.