Quantitative proteomics analysis reveals the tolerance of Mirabilis jalapa L. to petroleum contamination.

Petroleum is not only an important energy resource but is also a major soil pollutant. To gain better insight into the adaptability mechanism of Mirabilis jalapa to petroleum-contaminated soil, the protein profiles of M. jalapa root were investigated using label-free quantitative proteomics technique. After exposing to petroleum-contaminated soil for 24 h, 34 proteins significantly changed their protein abundance and most of the proteins increased in protein abundance (91.18%). Combined with gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses as well as data from previous studies, our results revealed that M. jalapa enhanced tolerance to petroleum by changing antioxidation and detoxification, cell wall organization, amino acid and carbohydrate metabolism, transportation and protein process, and so on. These metabolism alterations could result in the production and secretion of low molecular carbohydrate, amino acid, and functional protein, which enhanced the bioavailability of petroleum and reducing the toxicity of the petroleum. Taken together, these results provided novel information for better understanding of the tolerance of M. jalapa to petroleum stress.

Uptake and translocation of benzo[a]pyrene (B[a]P) in two ornamental plants and dissipation in soil.

Pot experiments were conducted to evaluate the phytoremediation of B[a]P contaminated soil using two ornamental plants (Tagetes patula and Mirabilis jalapa). The results showed that the dry biomass of two plants was increased at low B[a]P contaminated soil and then inhibited with increasing B[a]P concentrations. It exhibited a significantly positive linear relationship between B[a]P absorption in roots, stems, leaves and shoots of the tested plants and the concentration of B[a]P in soils (P<0.01). Meanwhile, the contents of B[a]P in different tissues of the plants increased with growing time. After planting T. patula and M. jalapa, plant-promoted biodegradation of B[a]P was account for 79.5-99.8% and 71.1-99.9%, respectively, whereas the amount of B[a]P dissipation enhancement was only 0.2-20.5% and 0.1-28.9%, respectively. Moreover, low bioaccumulation factor (BF) and translocation factor (TF) values indicated that T. patula and M. jalapa took up B[a]P from contaminated soil and transferred them to the aerial parts with low efficiency. The B[a]P removal rates in rhizosphere soils at different growing stages of T. patula and M. jalapa were 2.7-26.8% and 0.4%-33.9%, respectively, higher than those of non-rhizopshere soils. Therefore, the presence of T. patula and M. jalapa roots was effective in promoting the phytoremediation of B[a]P contaminated soils.

Tolerance, uptake and removal of nitrobenzene by a newly-found remediation species Mirabilis jalapa L.

The growth, photosynthesis rate, and ultrastructure of Mirabilis jalapa L. as a newly-found remediation species under stress of nitrobenzene (NB) and its uptake and removal of NB by the plants were investigated. The results showed that M. jalapa plants could endure contaminated soils by lower than 10.0 mg NB kg(-1) because there was no decrease in the total length of the plant roots, the maximum length of the hypocotyle, the length of the first seminal root, the height of the shoots and the dry biomass of the seedlings as well as the photosynthesis rate of the plants compared with those in the control. In particular, the growth of the plants could be significantly (P<0.01) enhanced by 0.1 mg NB kg(-1) under unautoclaved and autoclaved soils. Ultrastructural observations on leaf cells of the plants found that these cells had smooth, clean and continuous cell membranes and cell walls, indicating that there was no obvious damage by NB in comparison with those in the control. Although the absorption of NB in shoots and roots of M. jalapa was weak, plant-promoted biodegradation of NB was considerable and the dominant contribution in the removal of NB from contaminated soils, suggesting the feasibility of M. jalapa applied to phytoremediation of NB contaminated soils.

Genes associated with opening and senescence of Mirabilis jalapa flowers.

A modest ethylene climacteric accompanies flower senescence in Mirabilis jalapa L., and exogenous ethylene accelerates the process. However, inhibitors of ethylene action and synthesis have little effect on the life-span of these ephemeral flowers. Treatment with alpha-amanitin, an inhibitor of DNA-dependent RNA synthesis, substantially delays the onset of senescence. This effect falls linearly between 7 h and 8 h after the start of flower opening. Subtractive hybridization was used to isolate transcripts that were up- and down-regulated during this critical period. Eighty-two up-regulated and 65 down-regulated transcripts were isolated. The genes identified encode homologues of a range of transcription factors, and of proteins involved in protein turnover and degradation. Real-time quantitative RT-PCR was used to examine expression patterns of these genes during flower opening and senescence. Genes that were identified as being down-regulated during senescence showed a common pattern of very high expression during floral opening. These genes included a homologue of CCA1, a 'clock' gene identified in Arabidopsis thaliana and an aspartyl protease. Up-regulated genes commonly showed a pattern of increase during the critical period (4-9 h after opening), and some showed very strong up-regulation. For example, the abundance of transcripts encoding a RING zinc finger protein increased >40 000 fold during the critical period.

Estudio farmacognóstico, fitoquímico y microbiológico de la Mirabilis jalapa L. 1998 / A pharmacodiagnostic, phytochemical and microbiological study of Mirabilis jalapa L. 1998

Se realizó un estudio en el Centro Provincial Desarrollo de la Medicina Tradicional y Natural a la droga Mirabilis jalapa L. (Maravilla), con el objetivo de conocer quiénes son los metabolitos responsables de la acción farmacológica que le es atribuida a la planta y se complementó con un estudio farmacognóstico y microbiológico. Dicho material vegetal fue previamente identificado y comparado con la muestra de Herbario #1215 del Jardín Botánico de Sancti-Spíritus, se recolectó en el mes de Octubre de 1998, en horas tempranas de la mañana, en áreas aledañas al poblado de Guayos. Se efectuó cuando las plantas se encontraban en su máximo estado de crecimiento y desarrollo, la misma se realizó al azar en bolsas de nylon y se trasladó hacia el lugar donde se realizó el estudio fitoquímico en forma fresca a la flor, de la cual se informaron sus características micro y macromorfológicas, estas se secaron a la sombra, sol y estufa con recirculación de aire, a una temperatura de 38 ºC. Posteriormente fueron trituradas y se determinó la composición química, no detectándose diferencias entre los metabolitos encontrados en la droga fresca y seca. A continuación se exponen los resultados de índices numéricos como: humedad residual, sustancias solubles, determinación de aceites esenciales, entre otros. Fue seleccionado el secado en estufa con recirculación de aire (38 ºC) como el de mayor eficacia para realizar el extracto fluido, el cual se elaboró por repercolación usando como menstruo una solución hidroalcohólica al 70% y se le hicieron estudios de estabilidad a temperatura ambiente y en refrigeración durante un período de 30 días, no presentó variaciones en su conservación. Se tomó una muestra de este preparado y se demostró la actividad antimicrobiana in vitro frente a las cepas de Staphylococos aureus coagulasa positivo, Escherichia coli y Candida albicans las cuales resultaron sensibles.[AU]