[Effect of magnesium deficiency on photosynthetic physiology and triacylglyceride (TAG) accumulation of Chlorella vulgaris].

As an excellent biological resource, Chlorella has wide applications for production of biofuel, bioactive substances and water environment restoration. Therefore, it is very important to understand the photosynthetic physiology characteristics of Chlorella. Magnesium ions play an important role in the growth of microalgae, not only the central atom of chlorophyll, but also the cofactor of some key enzyme in the metabolic pathway. A laboratory study was conducted to evaluate the effects of magnesium deficiency on several photosynthetic and physiological parameters and the triacylglyceride (TAG) accumulation of the green alga, Chlorella vulgaris, in the photoautotrophic culture process. Chlorella vulgaris biomass, protein, chlorophyll a and chlorophyll b contents decreased by 20%, 43.96%, 27.52% and 28.07% in response to magnesium deficiency, while the total oil content increased by 19.60%. Moreover, magnesium deficiency decreased the maximal photochemical efficiency F(v)/F(m) by 22.54%, but increased the non-photochemical quenching parameters qN. Our results indicated the decline of chlorophyll caused by magnesium, which affected the photosynthesis efficiency, lead to the growth inhibition of Chlorella vulgaris and affected the protein synthesis and increased the triacylglyceride (TAG) accumulation.

[Research progress in medicinal plant cell suspension culture].

China consumes and exports traditional Chinese medicinal resources the most in the world. However, we cannot anchor our hope on field production of traditional Chinese medicinal materials and their active ingredients, due to limited land resources. Therefore, the development of biotechnology is of great importance for China to solve the problem of traditional Chinese medicinal resources. Plant cell culture is an important approach for the sustainable development of precious medicinal resources. This essary summarizes the optimization of conditions for medicinal plant cell culture, the regulation of secondary metabolic pathways and cell bioreactor culture, and realizes that the authentic commercial production of more medicinal plants requires efforts from all aspects.