Variation in Isoflavone of Soybean Cultivars with Location and Storage Duration

Abstract

Fifteen soybean [Glycine max (L.) Merrill] cultivars were grown in Seoul, Suwon, and Kyongsan, Korea, in 1998, 1999, and 2000, and their isoflavone contents were assessed. After harvest, the beans were stored for 3 years at room temperature. Soybean isoflavones were analyzed using high-performance liquid chromatography (HPLC) within each crop year and after storage. Total isoflavone contents ranged from 188.4 to 685.6 mg 100 g(-1) in 1998, from 218.8 to 948.9 mg 100 g(-1) in 1999, and from 293.1 to 483.0 mg 100 g(-1) in 2000. The year x variety, and year x location x variety interactions were significantly different in 1998, the year x location, year x variety, and year x location x variety interactions were significantly different in 1999, and the year x variety interaction was significantly different in 2000 for total and individual isoflavone contents. Total isoflavone contents of soybeans stored for 1 year were only slightly higher than those of soybeans stored for 2 or 3 years. However, the concentrations of individual isoflavones, especially 6' '-O-malonyldaidzin and 6' '-O-malonylgenistin, decreased markedly in soybeans stored for 2 or 3 years. These data suggest that it may be feasible to improve soybean cultivars with higher antioxidative substances.

Resíduos de glifosato e ácido aminometilfosfônico e teores de isoflavonas em soja BRS 244 RR e BRS 154

“…A ausência de acetilglicosídeos está justificada uma vez que sua formação está associada a processamentos envolvendo calor seco, como a tostagem e a extrusão da farinha de soja (COWARD et al, 1998). Por outro lado, a formação de agliconas resulta da atuação das β-glicosidases endógenas, como, por exemplo, quando a soja é deixada de molho ou mesmo durante armazenamento prolongado em condições de alta umidade relativa (MATSUURA et al, 1989;LEE et al, 2003). Isso explica a baixa porcentagem presente nas sementes, cuja formação foi provavelmente decorrente do processo de moagem e extração da soja para a análise.…”

Isoflavones in processed soybean products from Ecuador

“…Isoflavone contents of soy products are presented in Table 2 and representative HPLC chromatograms in Figure 1 (except for that of soy seeds presenting the same content of the raw whole soybean flour). Total isoflavone content varied among different soy varieties and environmental growing conditions (Wang and Murphy, 1994;Lee et al, 2003) and the Ecuadorian variety (~ 68 mg per 100 g) was found in the same range of Brazilian varieties, from 57 to 188 mg per 100 g of soybeans (Genovese et al, 2005) and could be considered low when compared to American (116 to 274 mg/100 g) and Korean varieties (188 to 949 mg/100 g) (Wang et al, 2000;Lee et al, 2003). The soy products represent a way of incorporating isoflavones in the diet of populations that do not consume the grains.…”

Effects of Different Carriers on the Production of Isoflavone Powder from Soybean Cake

“…These levels were much higher than those reported by Wang et al [18] or Coward et al [19], who found malonylglucoside, glucoside, acetylglucoside and aglycone levels to be 1,013 and 1,340 µg/g, 475 and 249 µg/g, 0 and 207 µg/g, and 24 and 11 µg/g, respectively. These differences may be accounted for by variations in cultivar, growth environment, harvest time and storage conditions [6,20]. …”

“…By comparing maltodextrin concentrations of 20 % were also compared and the optimum level was found to be 20 %. By controlling the inlet temperature at 180 °C and outlet temperature at 120 °C, a total amount of 7.9 g powder (6.1% H 2 O) containing 1,887 µg/g isoflavone was obtained after spray drying.…”