Changes of Folate and Other Potential Health-Promoting Phytochemicals in Legume Seeds As Affected by Germination M. J. I. Shohag, ∥ Yanyan Wei, ∥ and Xiaoe Yang* Ministry of Education (MOE) Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Hangzhou 310058, People’s Republic of China ABSTRACT: Folate deficiency associated with low dietary intake is a well-documented public health problem, resulting in serious health and socioeconomic burdens. Therefore, optimization of the germination process of different cultivars of legume seeds in relation to the content and composition of folate, vitamin C, and total phenolics and total antioxidant capacity was carried out to maximize the health-promoting properties. The content and composition of folate, vitamin C, and total phenolic and total antioxidant capacities varied between species, among cultivars, and with germination time. During germination, total folate content was maximum at 815.2 μg/100 g fresh weight in soybean sprout and at 675.4 μg/100 g fresh weight in mungbean sprout on the fourth day, which were equivalent to, respectively, 3.5- and 3.9-fold increases in the seed’s content, and total folate content strongly decreased thereafter. 5-CH 3 -H 4 folate was the most abundant folate species in legume sprouts and reached a maximum on the fourth day. Vitamin C was not detected in raw seeds, and its content increased sharply in soybean and mungbean sprouts and reached a maximum at the fourth day of germination (29 and 27.7 mg/100 g fresh weight, respectively). Germination of soybean and mungbean for 4 days provided the largest amount of total folate as well as the more stable species 5- CH 3 -H 4 folate and also brought about large amounts of vitamin C and total phenolics and substantial antioxidant capacities. KEYWORDS: folate, phytochemicals, sprout, soybean, mungbean ■ INTRODUCTION Folate deficiency is a well-documented public health problem in the developing world, resulting in severe health and socio- economic burdens. 1,2 Folate deficiency decreases DNA biosyn- thesis and thus affects cellular functions, growth, and development. There are a variety of disorders associated with folate deficiency, including neural tube defects (NTDs), such as spina bafida and anencephaly, megaloblastic anemia, occlusive vascular disease, colon cancer, Down’ s syndrome, and Alzheimer’s disease. 3,4 Folate deficiency causes approximately 300 000 NTDs per year 5 and is responsible for 10% of adult deaths from heart disease. 6 Furthermore, folate deficiency is the main cause of anemia in at least 10 million pregnant women in the developing world. 7 Humans and animals cannot synthesize folates de novo and, therefore, depend completely on their dietary sources. 2 Thus, plant foods are the main source of folates in the human diet. Food folate levels vary among different crops species; the staples wheat, maize, and, especially, rice contain low amounts of folates to meet the recommended dietary allowances (RDAs) of 400 μg/day for adults and 600 μg/day for pregnant women. 8 Enrichment of food with folate is, therefore, an important global challenge and high priority in research. Defeating folate deficiency in humans is a tremendous challenge. Several strategies have been proposed to fight folate deficiency. Folate biofortification, the enhancement of folates in crop through plant breeding or biotechnology, offers the most sustainable solution; 1 it is, however, a long-term process. Supplementation and food fortification strategies, however, are less feasible in developing countries due to economic or social reasons. 9 Moreover, concerns have arisen about human life- threatening diseases due to chronic exposure to synthetic folic acid from the fortified foods. 4 In contrast to synthetic folic acid fortification, a natural way to increase folate levels is germination of edible plant seeds as has been reported in recent years. 10,11 During germination, rapid cell division increases the demand for carbon one units for cell metabolism and for nucleotide biosynthesis; as a result, folate synthesis is accelerated in developing seedlings. 12,13 In this way, contents of folates have been reported to increase 1.7−4.3 times compared with ungerminated seeds. 10,11 A complement or alternative to mandatory folic acid fortification could be to increase the natural folate content by sprouting. It has been widely reported that sprouts provide higher nutritive value than raw seeds, and their production is simple and inexpensive. Legume species sprouts are becoming a functional food that has been recommended for the human diet because they have the advantages of germinated seeds. In comparison to other legume seeds surveyed, soybean and mungbean seeds appear to be superior in folate content 14 and, therefore, offer the possibility of decisively increasing folate intake by sprouting. However, folate deficiency in several Asian countries such as China is partly attributed to the off-season limited supply of fresh vegetables. 1,15 Legume sprouts can be produced within a short time in households; hence, they could be an alternative and vital source of folate during the off-season of vegetable supply. For that purpose, we focused on the optimization in key legume sprouts bioactives (folate, vitamin Received: June 2, 2012 Revised: August 20, 2012 Accepted: August 20, 2012 Published: August 20, 2012 Article pubs.acs.org/JAFC © 2012 American Chemical Society 9137 dx.doi.org/10.1021/jf302403t | J. Agric. Food Chem. 2012, 60, 9137−9143