Researchers at the University of Geneva (UNIGE), in collaboration with ETH Zurich and Taiwan’s National Chung Hsing University (NCHU), have made significant progress in the fight against vitamin B1 deficiency, often associated with rice-based diets. Ta. Their results are Plant Biotechnology Journalcould help solve major public health problems in areas where rice is a staple food.
Although most vitamins cannot be produced by the human body and must be supplied through a varied diet, deficiencies are common in populations where grains such as rice are the main or only food source. is. This is especially true for vitamin B1 (thiamine), whose deficiency is the cause of many neurological and cardiovascular diseases.
Rice is a staple crop for half of the world’s population, especially in tropical countries of Asia, South America, and Africa. Rice grains contain little vitamin B1, and processing processes such as rice milling (grinding the outer layer to remove the bran) further reduce vitamin B1, resulting in 90% of it being ingested along with vitamin B1. Therefore, this habit further exacerbates chronic deficiencies.
Teresa Fitzpatrick’s laboratory, a full professor in UNIGE’s Department of Plant Sciences, specializes in vitamin biosynthesis and degradation pathways in plants. Her group, in collaboration with ETH Zurich and NCHU, focused on improving the vitamin B1 content of rice endosperm, the vegetative tissue that makes up the bulk of the seed.
“Previous biofortification efforts by other teams have been successful in increasing the vitamin B1 content of leaves and bran (outer layer of rice grains), but not in ready-to-eat rice grains. I didn’t,” Fitzpatrick said. “In our study, we specifically focused on increasing vitamin B1 content in the endosperm.”
The researchers generated a rice line that expresses a gene that sequesters vitamin B1 in endosperm tissue in a controlled manner. When grown in a greenhouse, the rice grains were harvested and polished, the rice grains from these lines were found to have increased vitamin B1 content. This line was then sown in an experimental field in Taiwan and grown for several years.
From an agronomic point of view, the analyzed traits were the same for both modified and unmodified rice, with plant height, number of stems per plant, grain weight, and fertility all being comparable. However, the level of vitamin B1 in the rice grains after the milling stage increased 3-4 times in the improved lines. Therefore, this modification allows accumulation of vitamin B1 without affecting yield.
“Most of this kind of research is carried out using crops grown in greenhouses,” said Wilhelm Gruissem, professor emeritus at ETH Zurich and Distinguished Professor and Jade Mountain Fellow at NCHU. “The fact that we were able to grow the line under real field conditions [and] It is very promising that the expression of the modified genes is stable over a long period of time without affecting the agronomic properties. ”
300 grams of rice made from this crop provides about one-third of the recommended daily intake of vitamin B1 for adults. The next step is to pursue this approach in commercial varieties. However, growing these plants requires regulatory measures regarding biofortification through genetic engineering.
