Presently, the Crop Metabolism Regulation and Nutrition Innovation Team of Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, make advance in high astaxanthin maize new germplasm research. Related results published in Plant Biotechnology Journal.
Astaxanthin is a kind of carotenoid, which usually exists in marine organisms such as algae, shrimp and crab. It is widely used in life because of its strong antioxidant and health care efficacy. In this study, reported a new strategy for expressing β-carotene ketolase and hydroxylase genes from algae, yeasts and flowering plants in the whole seed using a seed-specific bidirectional promoter. Engineered maize events were backcrossed to inbred maize lines with yellow endosperm to generate progenies that accumulate astaxanthin from 47.76 to 111.82 mg/kg DW in seeds, and the maximum level is approximately sixfold higher than those in previous reports (16.2–16.8 mg/kg DW) in cereals. A feeding trial with laying hens indicated that they could take up astaxanthin from the maize and accumulate it in egg yolks (12.10–14.15 mg/kg) without affecting egg production and quality, as observed using astaxanthin from Haematococcus pluvialis, and the astaxanthin content of each egg is about 540 μg. It can meet the daily antioxidant health care needs of human body. The research results reflect the effectiveness and scalability of biotechnology in creating nutritional fortified products beneficial to human health. The created nutritional fortified products have broad application prospects.

 
This work was supported by the National Special Program for GMO Development of China (grant number 2016ZX08003-002). Dr. Liu Xiaoqing and Miss. Ma xuhui of BRI for the first author of the article, Professor Zhang Junmin and Professor Chen Rumei as the author of the communication.
Article link: https://onlinelibrary.wiley.com/doi/10.1111/pbi.13593