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Ratnadewi D.,Bogor Agricultural University | Satriawan D.,University of Bengkulu | Sumaryono,Indonesian Biotechnology Research Institute for Estate Crops
Biotropia | Year: 2013

Quinine is one of the major alkaloids in Cinchona spp., and it is used both as a medication and as a drink additive. The plant produces most of its alkaloids in the bark after 68 years of age. Repeated harvests can be performed until the plant dies, but only after every 35 years. We tested an improved method for culturing cell suspensions of Cinchona ledgeriana investigate the possibility of increasing production of quinine. The clone QRC 315 was treated with either a growth retardant (abscisic acid or paclobutrazol) or precursor feeding of L-tryptophan. To generate stress, we applied mannitol at 5.3 g/L combined with sucrose at a lower concentration (20 g/L), and we used sucrose at 30 g/L as the control. Paclobutrazol (7 mg/L) significantly suppressed cell growth and produced the highest level of quinine (11%) after 7 weeks of culture. L-tryptophan also reduced cell growth, but without any positive effect in the production of quinoline. The highest amount of quinine per culture flask, however, resulted from cells treated with 3 mg/L abscisic acid.

Hernandez-Moreno D.,Wageningen University | Hernandez-Moreno D.,University of Extremadura | Soffers A.E.M.F.,Wageningen University | Wiratno,Wageningen University | And 4 more authors.
Food and Chemical Toxicology | Year: 2013

This study presents a consumer and farmer safety evaluation on the use of four botanical pesticides in pepper berry crop protection. The pesticides evaluated include preparations from clove, tuba root, sweet flag and pyrethrum. Their safety evaluation was based on their active ingredients being eugenol, rotenone, β-asarone and pyrethrins, respectively.Botanical pesticides from Acorus calamus are of possible concern because of the genotoxic and carcinogenic ingredient β-asarone although estimated margins of exposure (MOE) for consumers indicate a low priority for risk management.For the other three botanical pesticides the margin of safety (MOS) between established acute reference doses and/or acceptable daily intake values and intake estimates for the consumer, resulting from their use as a botanical pesticide are not of safety concern, with the exception for levels of rotenone upon use of tuba root extracts on stored berries. Used levels of clove and pyrethrum as botanical pesticides in pepper berry crop production is not of safety concern for consumers or farmers, whereas for use of tuba root and sweet flag some risk factors were defined requiring further evaluation and/or risk management. It seems prudent to look for alternatives for use of sweet flag extracts containing β-asarone. © 2013 Elsevier Ltd.

Piyatrakul P.,CIRAD - Agricultural Research for Development | Piyatrakul P.,Rubber Research Institute | Yang M.,CAS Beijing Institute of Genomics | Putranto R.-A.,CIRAD - Agricultural Research for Development | And 9 more authors.
PLoS ONE | Year: 2014

The AP2/ERF superfamily encodes transcription factors that play a key role in plant development and responses to abiotic and biotic stress. In Hevea brasiliensis, ERF genes have been identified by RNA sequencing. This study set out to validate the number of HbERF genes, and identify ERF genes involved in the regulation of latex cell metabolism. A comprehensive Hevea transcriptome was improved using additional RNA reads from reproductive tissues. Newly assembled contigs were annotated in the Gene Ontology database and were assigned to 3 main categories. The AP2/ERF superfamily is the third most represented compared with other transcription factor families. A comparison with genomic scaffolds led to an estimation of 114 AP2/ERF genes and 1 soloist in Hevea brasiliensis. Based on a phylogenetic analysis, functions were predicted for 26 HbERF genes. A relative transcript abundance analysis was performed by real-time RT-PCR in various tissues. Transcripts of ERFs from group I and VIII were very abundant in all tissues while those of group VII were highly accumulated in latex cells. Seven of the thirty-five ERF expression marker genes were highly expressed in latex. Subcellular localization and transactivation analyses suggested that HbERF-VII candidate genes encoded functional transcription factors.

Putranto R.-A.,CIRAD - Agricultural Research for Development | Putranto R.-A.,Indonesian Biotechnology Research Institute for Estate Crops | Sanier C.,CIRAD - Agricultural Research for Development | Leclercq J.,CIRAD - Agricultural Research for Development | And 8 more authors.
Plant Science | Year: 2012

Three types of roots (taproots, first order laterals and second order laterals) were functionally characterized on 7-month-old in vitro plantlets regenerated by somatic embryogenesis in Hevea brasiliensis. A histological analysis revealed different levels of differentiation depending on root diameter. A primary structure was found in first and second order lateral roots, while taproots displayed a secondary structure. The expression of 48 genes linked to some of the regulatory pathways acting in roots was compared in leaves, stems and the different types of roots by real-time RT-PCR. Thirteen genes were differentially expressed in the different organs studied in plants grown under control conditions. Nine additional other genes were differentially regulated between organs under water deficit conditions. In addition, 10 genes were significantly regulated in response to water deficit, including 8 regulated mainly in lateral roots types. Our results suggest that the regulation of gene expression in lateral roots is different than that in taproots, which have a main role in nutrient uptake and transport, respectively. © 2011 Elsevier Ireland Ltd.

Iskandar H.M.,CSIRO | Iskandar H.M.,University of Queensland | Iskandar H.M.,Indonesian Biotechnology Research Institute for Estate Crops | Casu R.E.,CSIRO | And 7 more authors.
BMC Plant Biology | Year: 2011

Background: The ability of sugarcane to accumulate high concentrations of sucrose in its culm requires adaptation to maintain cellular function under the high solute load. We have investigated the expression of 51 genes implicated in abiotic stress to determine their expression in the context of sucrose accumulation by studying mature and immature culm internodes of a high sucrose accumulating sugarcane cultivar. Using a sub-set of eight genes, expression was examined in mature internode tissues of sugarcane cultivars as well as ancestral and more widely related species with a range of sucrose contents. Expression of these genes was also analysed in internode tissue from a high sucrose cultivar undergoing water deficit stress to compare effects of sucrose accumulation and water deficit.Results: A sub-set of stress-related genes that are potentially associated with sucrose accumulation in sugarcane culms was identified through correlation analysis, and these included genes encoding enzymes involved in amino acid metabolism, a sugar transporter and a transcription factor. Subsequent analysis of the expression of these stress-response genes in sugarcane plants that were under water deficit stress revealed a different transcriptional profile to that which correlated with sucrose accumulation. For example, genes with homology to late embryogenesis abundant-related proteins and dehydrin were strongly induced under water deficit but this did not correlate with sucrose content. The expression of genes encoding proline biosynthesis was associated with both sucrose accumulation and water deficit, but amino acid analysis indicated that proline was negatively correlated with sucrose concentration, and whilst total amino acid concentrations increased about seven-fold under water deficit, the relatively low concentration of proline suggested that it had no osmoprotectant role in sugarcane culms.Conclusions: The results show that while there was a change in stress-related gene expression associated with sucrose accumulation, different mechanisms are responding to the stress induced by water deficit, because different genes had altered expression under water deficit. © 2011 Iskandar et al; licensee BioMed Central Ltd.

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