红花细胞和组织培养研究进展

红花是重要的油药两用作物,本文对红花细胞和组织培养的国内外研究进展进行了综述,主要包括愈伤组织的诱导、次生代谢产物的合成及细胞的大规模培养、器官发生、体细胞胚胎发生等几个方面,并对该领域的发展前景进行了展望.     

Buckwheat in Tissue Culture Research: Current Status and Future Perspectives

Buckwheat is a member of a genus of 23 species, where the two most common species are Fagopyrum esculentum (common buckwheat) and Fagopyrum tataricum (Tartary buckwheat). This pseudocereal is a source of micro and macro nutrients, such as gluten-free proteins and amino acids, fatty acids, bioactive compounds, dietary fibre, fagopyrins, vitamins and minerals. It is gaining increasing attention due to its health-promoting properties. Buckwheat is widely susceptible to in vitro conditions which are used to study plantlet regeneration, callus induction, organogenesis, somatic embryogenesis, and the synthesis of phenolic compounds. This review summarises the development of buckwheat in in vitro culture and describes protocols for the regeneration of plantlets from various explants and differing concentrations of plant growth regulators. It also describes callus induction protocols as well as the role of calli in plantlet regeneration. Protocols for establishing hairy root cultures with the use of Agrobacterium rhizogens are useful in the synthesis of secondary metabolites, as well as protocols used for transgenic plants. The review also focuses on the future prospects of buckwheat in tissue culture and the challenges researchers are addressing.     

苯丙氨酸和茉莉酸甲酯对百里香离体培养芽生长及其精油的影响

以离体培养的百里香不定芽为材料,研究了培养基添加不同浓度的苯丙氨酸(phenylalanine,Ple)或茉莉酸甲酯(methyl jasmonate,MJ)对不定芽生长以及精油提取率等的影响。结果发现添加供试浓度的Ple和MJ都能不同程度促进不定芽的增殖,其中以添加100 mg/L Ple和150μmol/L MJ增殖效果最佳,增殖系数分别比对照显著增加47.03%和23.57%。采用水蒸气蒸馏法提取了普通百里香(Thymus vulgaris L.)组培苗、以及培养基添加苯丙氨酸或茉莉酸甲酯的普通百里香[0]组培苗的精油,添加100 mg/L Ple和150μmol/L MJ的提取率分别为0.42%和0.39%,分别比对照(0.31%)增加了35.5%和25.8%。利用气质联用法(GC-MS)并结合色谱峰面积归一化法对其化学成分和相对含量进行了比较研究,3种组培苗百里香精油的主要化学成分无明显的差异,都含有百里香精油的主要成分百里香酚、香芹酚、邻-伞花烃、γ-松油烯、石竹烯等,只是相对含量略有差异。研究表明,适宜浓度的苯丙氨酸和茉莉酸甲酯不仅提高了百里香不定芽的增殖系数,改善了植株的生理活性,而且还促进了百里香次生代谢产物的积累和合成。     

The Effect of the Stress-Signalling Mediator Triacontanol on Biochemical and Physiological Modifications in Dracocephalum forrestii Culture

Triacontanol (TRIA) has been reported to influence signal transduction in the crosstalk triggered by various stress factors. As a signal player, it is also known to affect many physiological processes, including enhancing the biosynthesis of secondary metabolites. Such knowledge can be used to direct or boost the production of bioactive secondary compounds without stress induction. Therefore, the aim of this study is to evaluate the use of TRIA as a factor stimulating the growth and production of bioactive compounds in the shoot culture of Dracocephalum forrestii. TRIA was applied at three concentrations (2.5, 5, and 10 µM), alone or in combination with phytohormones (6-benzylaminopurine and indole-3-acetic acid). After five weeks, growth and physiochemical parameters (chlorophyll content, antioxidant enzyme activity, and phenolic acid level) were determined. The results indicate that TRIA application significantly increased shoot dry weight, chlorophyll content, antioxidant enzyme activities (superoxide dismutase, peroxidase, and catalase), and total polyphenol level; it also influenced the multiplication ratio in combination with growth regulators. The greatest antioxidant enzyme activity was observed for 5 µM TRIA in hormone-free medium, while the most significant secondary metabolite production was obtained for phytohormone-containing medium supplemented with 10 µM TRIA: total phenolic acid content (19.4 mg/g dry weight) was twice that of the control. Hence, the TRIA application appears to be a valuable biotechnology technique for modifying plant metabolite production.     

Molecular Identification of Endophytic Bacteria in Leucojum aestivum In Vitro Culture,NMR-Based Metabolomics Study and LC-MS Analysis Leading to Potential Amaryllidaceae Alkaloid Production

In this study, endophytic bacteria belonging to the Bacillus genus were isolated from in vitro bulblets of Leucojum aestivum and their ability to produce Amaryllidaceae alkaloids was studied. Proton Nuclear Magnetic Resonance (¹H NMR)-based metabolomics combined with multivariate data analysis was chosen to compare the metabolism of this plant (in vivo bulbs, in vitro bulblets) with those of the endophytic bacteria community. Primary metabolites were quantified by quantitative ¹H NMR (qNMR) method. The results showed that tyrosine, one precursor of the Amaryllidaceae alkaloid biosynthesis pathway, was higher in endophytic extract compared to plant extract. In total, 22 compounds were identified including five molecules common to plant and endophyte extracts (tyrosine, isoleucine, valine, fatty acids and tyramine). In addition, endophytic extracts were analyzed using Liquid Chromatography-Mass Spectrometry (LC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS) for the identification of compounds in very low concentrations. Five Amaryllidaceae alkaloids were detected in the extracts of endophytic bacteria. Lycorine, previously detected by ¹H NMR, was confirmed with LC-MS analysis. Tazettine, pseudolycorine, acetylpseudolycorine, 1,2-dihydro-chlidanthine were also identified by LC-MS using the positive ionization mode or by GC-MS. In addition, 11 primary metabolites were identified in the endophytic extracts such as tyramine, which was obtained by decarboxylation of tyrosine. Thus, Bacillus sp. isolated from L. aestivum bulblets synthesized some primary and specialized metabolites in common with the L. aestivum plant. These endophytic bacteria are an interesting new approach for producing the Amaryllidaceae alkaloid such as lycorine.