1B). Isoflavones containing a genistein core were found in a slightly higher proportion than those containing a daidzein core, 52.4% and 42.4%, respectively. Only 5.2% of isoflavones contained a glycitein core. In general, these relative contents were different than those of other studies (Genovese and Lajolo, 2002, Murphy et al., 1997 and Setchell et al., 1997), which reported higher proportions of isoflavones containing genistein (mean of 61%) and glycitein cores (mean of 9%) and lower proportion of daidzein core isoflavones (mean of 30%). Daidzein and genistein have been shown to have a weak oestrogenic activity and are able to bind with a low affinity to oestrogen receptors
(Fehily, 2003). In relation to antioxidant activity, it Panobinostat has been reported that genistein is more effective than daidzein, since the former contains two hydroxyl groups while BMN 673 in vitro the latter contains only one. Moreover, glycitein shows a reduced antioxidant activity due to the blocking of hydroxyl through methylation (Rüfer and Kulling, 2006). Soyasaponins contents in the analysed infant formula samples
are given in Table 4. The total soyasaponins contents ranged between 17.9 and 113.5 mg/100 g, with a mean content of 55.0 mg/100 g (Table 4). The large variation of total soyasaponins contents observed in our samples is probably a reflection of the soy protein composition used in the formula’s manufacture and agrees with data from Murphy et al. (2008), which reported a wide range of 71.8–320.7 mg/100 g. Murphy et al. (2008) reported that the total soyasaponins mean content of six soy-based
infant formula samples acquired in three different locations in the US was 199.4 mg/100 g, 3.6 times higher than those found in our samples. It should be noted that these authors analysed soyasaponins B-V, B-αg, B-βg and B-βa in addition to B-I and B-II, which were evaluated in the present study, but have not analysed soyasapogenol B, which was found in three of the samples analysed in the present study. Even if we only consider soyasaponins B-I and B-II, the samples analysed by Murphy et al. (2008) showed contents 3.6 times higher (159.9 mg/100 g) than those observed in the present study. The total soyasaponins contents observed in the present study were similar to that tuclazepam reported by Fang et al. (2004) (117.7 mg/100 g), who analysed a soy protein isolate sample. For such comparison, we took into consideration that our infant formulas samples contained a mean of 15.6% of soy protein. The major soyasaponin present in the infant formulas samples was soyasaponin B-I, which corresponded to a mean of 65.5% of total soyasaponins content, with the exception of Nan Soy, in which soyasapogenol B was the most abundant (55.4%) soyasaponin. Soyasaponins B-II and B-III accounted together for 21.7% of soyasaponins content.