ABSTRACT
Astaxanthin is widely applied as a nutraceutical, pharmaceutical, and aquaculture feed additive because of its high antioxidant activity. Haematococcus pluvialis is a microalgal species that can largely accumulate astaxanthin under adverse environmental conditions. Here we review the research progress of astaxanthin biosynthesis in H. pluvialis, including the induction and regulation of massive astaxanthin, the relationship between astaxanthin synthesis, photosynthesis and lipid metabolism.
Subject(s)
Chlorophyceae , Chlorophyta , Microalgae , XanthophyllsABSTRACT
The low lipid content is one of the major bottlenecks to realize the industrialization of the algae biodiesel. Improvement of lipid content through global regulation to get high-yield generating algae is a good strategy. Leafy Cotyledon 2 (LEC2) is an important transcription factor for seed maturation and oil accumulation in Arabidopsis. However, there are few reports regarding adoption of LEC2 for lipid accumulation until now. In this study, LEC2 from Arabidopsis was cloned into the plant expression vector pCIMBIA1300 and transformed into C. sorokiniana through particle bombardment. One recombinant was screened by PCR, RT-PCR and Western blot analyses. Compared with the wild type one, the total lipid content in the recombinant increased one fold, which did not show effect on cell growth, indicating that LEC2 can efficiently enhance the lipid accumulation in C. sorokiniana.
ABSTRACT
Objective To establish an optimum DNA extraction method for Chinese traditional medical herbs in order to meet necessary for DNA barcoding research.Methods Four Chinese traditional herbs, Glycyrrhiza uralensis Fisch, Phellodendron Chinensis Cortex, Cistanche tubulosa Wight and Cistanche deserticola Ma were chosen as the experimental materials, the DNA was extracted by 6 different kinds of DNA extraction method, including the improved method of high-salt combined low-pH,the improved method of SDS,CTAB method,PVP method,PlantZol Kit and Ezup Kit, the quality of DNA was investigated by ultraviolet spectrophotometry,agarose gel electrophoresis and PCR amplification by using specific primers of ITS2 and psbA-trnH. ResuIts The quality of the DNA was better than other four kinds of methods by the improved method of high-salt combined low-pH and Ezup Kit, the value of OD260/OD280 was between 1.7 ~1.9,the yield of DNA was the highest by the PlantZol kit , followed by the improved method of high-salt combined low-pH( P <0.05 ) , but the purity of DNA was poor by the PlantZol kit.The DNA electrophoresis tests showed that the DNA integrity of Glycyrrhiza uralensis Fisch and Cistanche tubulosa Wight were better with the improved method of high-salt combined low-pH, the improved SDS method, the CTAB method and the PlantZol kit.The DNA of Phellodendron Chinensis Cortex and Cistanche deserticola Ma were extracted by the six methods appeared diffuse status in the lanes.But only the improved method of high-salt combined low-pH could make the PCR amplification of the success rate 100% by using specific primers of ITS2 and trnH-psbA.ConcIusion The DNA extraction method of high-salt combined low-pH can be used to establish the Chinese DNA barcoding which has the advantages of lower cost, simpler procedure and less time.