83 research outputs found
CYP72A67 catalyses a key oxidative step in Medicago truncatula hemolytic saponin biosynthesis
In the Medicago genus, triterpenic saponins are bioactive secondary metabolites constitutively synthesized
in the aerial and subterranean parts of plants via the isoprenoid pathway. Exploitation of saponins
as pharmaceutics, agrochemicals and in the food and cosmetic industries has raised interest in identifying
the enzymes involved in their synthesis. We have identified a cytochrome P450 (CYP72A67) involved in
hemolytic sapogenin biosynthesis by a reverse genetic TILLING approach in a Medicago truncatula ethylmethanesulfonate
(EMS) mutagenized collection. Genetic and biochemical analyses, mutant complementation,
and expression of the gene in a microsome yeast system showed that CYP72A67 is responsible for
hydroxylation at the C-2 position downstreamof oleanolic acid synthesis. The affinity of CYP72A67 for substrates
with different substitutions at multiple carbon positions was investigated in the same in vitro yeast
system, and in relation to two other CYP450s (CYP72A68) responsible for the production of medicagenic
acid, the main sapogenin in M. truncatula leaves and roots. Full sib mutant and wild-type plants were
compared for their sapogenin profile, expression patterns of the genes involved in sapogenin synthesis,
and response to inoculation with Sinorhizobium meliloti. The results obtained allowed us to revise the
hemolytic sapogenin pathway in M. truncatula and contribute to highlighting the tissue specificities
(leaves/roots) of sapogenin synthesis
New frontiers and emerging applications of 3D printing in ENT surgery: A systematic review of the literature
3D printing systems have revolutionised prototyping in the industrial field by lowering production time from days to hours and costs from thousands to just a few dollars. Today, 3D printers are no more confined to prototyping, but are increasingly employed in medical disci- plines with fascinating results, even in many aspects of otorhinolaryngology. All publications on ENT surgery, sourced through updated electronic databases (PubMed, MEDLINE, EMBASE) and published up to March 2017, were examined according to PRISMA guidelines. Overall, 121 studies fulfilled specific inclusion criteria and were included in our systematic review. Studies were classified according to the specific field of application (otologic, rhinologic, head and neck) and area of interest (surgical and preclinical education, customised surgical planning, tissue engineering and implantable prosthesis). Technological aspects, clinical implications and limits of 3D printing processes are discussed focusing on current benefits and future perspectives
Hypericum sp.: essential oil composition and biological activities
Phytochemical composition of Hypericum
genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced
by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization
as well as biological activities of H. perforatum
crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett
in Nat Prod Commun 5(9):1493–1506, 2010;
Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.Fundação para a Ciência e a Tecnologia (FCT) - project PTDC/AGR AAM/70418/2006, SFRH/BD/
13283/2003
Plant development and synthesis of essential oils in micropropagated and mycorrhizated plants of Origanum vulgare L. ssp. hirtum (Link) Ietswaart
Biomass production of micropropagated oregano was induced by inoculation with the fungus Glomus viscosum. The effects of arbuscular mycorrhizal (AM) symbiosis on morphological and metabolic variations of regenerated oregano plants were investigated at different growth stages. AM greatly increased parameters such as plant leaf area, fresh and dry weight, number of spicasters and verticillasters in infected plants. An increase of the gland density, especially on the upper leaf epidermis, was also observed following the physiological ageing of the tissues. The in vitro plants of O. vulgare ssp. hirtum described in this study provided a qualitatively and quantitatively good source of essential oils that have a chemical profile comparable to that of the control mother plants with carvacrol as the main compound
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