RESUMO
Herein we report on the generation of hairy root lines of P. scaberrima able to produce hernandulcin (HE), a non-caloric sweetener with nutraceutical properties. From ten different lines analyzed, three synthesized up to 100â mg â L-1 HE under the batch culture conditions standardized in this investigation. Adding elicitors (salicylic acid, chitin, Glucanex, polyethylene glycol) and biosynthetic precursors (farnesol and (+)-epi-alpha-bisabolol) significantly altered HE accumulation. Chitin and Glucanex enhanced HE production from 130 to 160â mg â L-1 , whereas farnesol and (+)-epi-alpha-bisabolol from 165 to 200â mg â L-1 without dependence on biomass accumulation. Improved batch cultures containing liquid Murashige & Skoog medium (MS; pHâ 7), added with 4 % sucrose, 0.5â mg â L-1 naphthaleneacetic acid, 100â mg â L-1 Glucanex, 150â mg â L-1 chitin, 250â mg â L-1 farnesol, and 150â mg â L-1 (+)-epi-alpha-bisabolol at 25 °C (12â h light/12â h darkness), triggered HE accumulation to 250â mg â L-1 in 25â days. The efficiency of each recombinant line is discussed.
Assuntos
Farneseno Álcool , Sesquiterpenos Monocíclicos , Sesquiterpenos , Edulcorantes , Edulcorantes/análise , Farneseno Álcool/análise , Suplementos Nutricionais , Quitina/análise , Raízes de Plantas/químicaRESUMO
Small RNAs are pivotal regulators of gene expression that guide transcriptional and post-transcriptional silencing mechanisms in eukaryotes, including plants. Here we report a comprehensive atlas of sRNA and miRNA from 3 species of algae and 31 representative species across vascular plants, including non-model plants. We sequence and quantify sRNAs from 99 different tissues or treatments across species, resulting in a data set of over 132 million distinct sequences. Using miRBase mature sequences as a reference, we identify the miRNA sequences present in these libraries. We apply diverse profiling methods to examine critical sRNA and miRNA features, such as size distribution, tissue-specific regulation and sequence conservation between species, as well as to predict putative new miRNA sequences. We also develop database resources, computational analysis tools and a dedicated website, http://smallrna.udel.edu/. This study provides new insights on plant sRNAs and miRNAs, and a foundation for future studies.