Progress and challenges in improving the nutritional quality of rice (Oryza sativaL.)

Abstract

Rice is a staple food for more than 3 billion people in more than 100 countries of the world but ironically it is deficient in many bioavailable vitamins, minerals, essential amino- and fatty-acids and phytochemicals that prevent chronic diseases like type 2 diabetes, heart disease, cancers, and obesity. To enhance the nutritional and other quality aspects of rice, a better understanding of the regulation of the processes involved in the synthesis, uptake, transport, and metabolism of macro-(starch, seed storage protein and lipid) and micronutrients (vitamins, minerals and phytochemicals) is required. With the publication of high quality genomic sequence of rice, significant progress has been made in identification, isolation, and characterization of novel genes and their regulation for the nutritional and quality enhancement of rice. During the last decade, numerous efforts have been made to refine the nutritional and other quality traits either by using the traditional breeding with high through put technologies such as marker assisted selection and breeding, or by adopting the transgenic approach. A significant improvement in vitamins (A, folate, and E), mineral (iron), essential amino acid (lysine), and flavonoids levels has been achieved in the edible part of rice, i.e., endosperm (biofortification) to meet the daily dietary allowance. However, studies on bioavailability and allergenicity on biofortified rice are still required. Despite the numerous efforts, the commercialization of biofortified rice has not yet been achieved. The present review summarizes the progress and challenges of genetic engineering and/or metabolic engineering technologies to improve rice grain quality, and presents the future prospects in developing nutrient dense rice to save the everincreasing population, that depends solely on rice as the staple food, from widespread nutritional deficiencies.

Proteomic analysis of reserve proteins in commercial rice cultivars

“…Nevertheless, there are some cases in which rice allergic reactions have been reported mainly in Japan and less frequently in Europe and the USA (Goliáš et al, ; González‐De‐Olano et al, ; Kumar et al, ; Villalta, Longo, Mistrello, Amato, & Asero, ). Rice allergy is more prominent in adults than in children (Kumar et al, ; Birla et al, ). The rice seed proteins responsible for allergy are α‐amylase/trypsin inhibitor (14–16 kDa) classified as albumins, α‐globulins, β‐glyoxylase, and several glutelins (Adachi et al, ; Birla et al, ; Usui et al, ).…”

“…Rice allergy is more prominent in adults than in children (Kumar et al, ; Birla et al, ). The rice seed proteins responsible for allergy are α‐amylase/trypsin inhibitor (14–16 kDa) classified as albumins, α‐globulins, β‐glyoxylase, and several glutelins (Adachi et al, ; Birla et al, ; Usui et al, ).…”

Use of biotechnological approaches to add value to rice hulls

“…Then, the out layer part of the brown rice is also removed (polishing process) originating the white rice. 5 The brown rice presents higher nutritional value than white rice, but lower shelf life, and the variability of sensory properties turns the white rice most popular among consumers. 6 Around 20% of grain total weight is composed by the hull, which is considered an agricultural waste.…”

Studies on Aroma Gene and its Application in Rice Genetics and Breeding

“…al., 2013;Haun et al, 2014;Liang et al, 2014;Wang et al, 2014). Among them, TALEN technology has also been applied to the genetics and breeding of aromatic rice (Shan et al, 2013(Shan et al, , 2015Birla et al, 2017). These new techniques provide a new strategy for rice breeders to cultivate aromatic rice varieties.…”

“…Then, using TALEN technology to knock out the Badh2 gene, one non-aromatic rice variety could be transformed into aromatic rice varieties (Shan et al, 2013), and the TALEN technology could also be used to create a genetically homozygous mutant of aromatic rice plant (Shan et al, 2015). Thus, the TALEN technology could be used to knock out the Badh2 gene in non-aromatic rice (Shan et al, 2015;Birla et al, 2017), and quickly produce the corresponding aromatic rice, which greatly accelerates the breeding process of the new varieties of high quality and high yield rice.…”