The importance of lactic acid bacteria for phytate degradation during cereal dough fermentation

Distaam, Università degli Studi del Molise, Via De Sanctis, 86100 Campobasso, Italy.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 05/2007; 55(8):2993-7. DOI: 10.1021/jf063507n
Source: PubMed

ABSTRACT Lactic acid fermentation of cereal flours resulted in a 100 (rye), 95-100 (wheat), and 39-47% (oat) reduction in phytate content within 24 h. The extent of phytate degradation was shown to be independent from the lactic acid bacteria strain used for fermentation. However, phytate degradation during cereal dough fermentation was positively correlated with endogenous plant phytase activity (rye, 6750 mU g(-1); wheat, 2930 mU g(-1); and oat, 23 mU g(-1)), and heat inactivation of the endogenous cereal phytases prior to lactic acid fermentation resulted in a complete loss of phytate degradation. Phytate degradation was restored after addition of a purified phytase to the liquid dough. Incubation of the cereal flours in buffered solutions resulted in a pH-dependent phytate degradation. The optimum of phytate degradation was shown to be around pH 5.5. Studies on phytase production of 50 lactic acid bacteria strains, previously isolated from sourdoughs, did not result in a significant production of intra- as well as extracellular phytase activity. Therefore, lactic acid bacteria do not participate directly in phytate degradation but provide favorable conditions for the endogenous cereal phytase activity by lowering the pH value.

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    • "Phytate degradations during fermentation range between 0 and 90% (Kruger, Taylor, & Oelofse, 2012; Reale et al., 2007; Reddy & Pierson, 1994; Towo, Matuschek, & Svanberg, 2006). This seems to be mainly related to the endogenous phytase activity of the plant matrix (Reale et al., 2007), since this correlation is not valid when grains or legumes are first heated before fermentation . It is known that the endogenous phytases are not stable at temperatures of 55 C or higher (Wodzinski & Ullah, 1996) and thus are deactivated during heating, resulting in a limited phytate degradation. "
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    ABSTRACT: Phytate, phenolic compounds and fiber are known anti-nutritional factors (ANF’s) that contribute to the low bioaccessibility and bioavailability of iron and zinc in plant foods. Better insight into the localization of minerals and anti-nutritional factors in plant tissues, as well as on the mechanisms of interaction between minerals and ANF’s, may lead to better targeted processing for improvement of the bioaccessibility of minerals in plant foods. This review highlights the subcellular distribution of iron and zinc and their ANF’s in plant organs, as well as the mechanisms of interaction between these metals and their ANF’s. These insights are then used to better clarify the role of various processing technologies, like mechanical treatments, soaking, germination, fermentation and heating, on improving the bioaccessibility of iron and zinc in plant foods.
    Trends in Food Science & Technology 05/2014; 37(1). DOI:10.1016/j.tifs.2014.02.002 · 4.65 Impact Factor
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    • "Many factors are known to play a role in the rate and the extent to which IP6 is degraded, among which the endogenous phytase activities of the raw materials and the processing conditions like pH, which is known to modulate the activities of both plant and microbial phytases (Greiner & Konietzny, 2006). The higher endogenous phytase activity of flour blends containing barley and wheat is consistent with the results of previous studies showing higher activities for these cereals (Egli, Davidsson, Juillerat , Barclay, & Hurrell, 2002; Reale et al., 2007) and IP6 degradation under the range of optimal pH values observed for barley and wheat phytases (Greiner & Konietzny, 2006). Moreover, the addition of malt in BW-and WrS-injeras possibly helps create a favourable environment for yeasts with phytase activities, indeed some strains of yeast species like Saccharomyces cerevisiae are known to display phytase activity (Vats & Banerjee, 2004). "
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    ABSTRACT: The influence of cereal blends, teff-white sorghum (TwS), barley-wheat (BW) and wheat-red sorghum (WrS), on fermentation kinetics during traditional fermentation of dough to prepare injera, an Ethiopian traditional fermented pancake, was investigated in samples collected in households. Barley malt was used with BW and WrS flours. WrS- and BW-injera sourdough fermentations were characterised by a transient accumulation of glucose and maltose and a two-step fermentation process: lactic acid fermentation and alcoholic fermentation with ethanol as the main end product. Only transient accumulation of glucose was observed in TwS-injera, and equimolar concentrations of lactic acid and ethanol were produced simultaneously. Final α-galactoside concentrations were low in all sourdoughs. Phytic acid (IP6) was completely hydrolyzed in WrS and BW-injeras probably due to the combined action of endogenous malt and microbial phytases. Only 28% IP6 hydrolysis was observed in TwS injera. Ways to improve IP6 hydrolysis in TwS-injera need to be investigated.
    Food Chemistry 05/2013; 138(1):430-6. DOI:10.1016/j.foodchem.2012.10.075 · 3.26 Impact Factor
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    • "Similar relationships between ash digestibility and lactose inclusion have been reported by O'Doherty et al. (2005). Research by Pierce et al. (2006) showed that high concentrations of lactose increased the concentration of lactic acid in the large intestine, which would provide favourable conditions for endogenous cereal phytase activity by lowering the pH of the hindgut (Reale et al., 2007). Increased phytase activity would enhance the phosphorus and mineral uptake in monogastric animals (Lassen et al., 2001). "
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    ABSTRACT: An experiment (3 × 4 factorial arrangement) was conducted to investigate the interaction between different levels of lactose (60 v. 150 v. 250 g/kg) and seaweed extract (0 v. 1 v. 2 v. 4 g/kg) containing both laminarin and fucoidan derived from Laminaria spp. on growth performance and nutrient digestibility of weanling pigs. In all, 384 piglets (24 days of age, 7.5 kg (s.d. 1 kg) live weight) were blocked on the basis of live weight and were assigned to one of 12 dietary treatments (eight replicates per treatment). Piglets were offered diets containing either low (60 g/kg), medium (150 g/kg) or high (250 g/kg) lactose levels with one of the following levels of seaweed extract additive: (1) 0 g/kg, (2) 1 g/kg, (3) 2 g/kg or (4) 4 g/kg seaweed extract. The pigs were offered the diets ad libitum for 21 days post weaning. There was a significant lactose × seaweed extract interaction (P < 0.05) in average daily gain (ADG) during the experimental period (days 0 to 21). At the low and medium levels of lactose, there was an increase in ADG as the level of seaweed extract increased to 2 g/kg (P < 0.05). However, at the high level of lactose there was no further response in ADG as the level of seaweed extract increased above 1 g/kg. There was a significant lactose × seaweed extract interaction during the experimental period (days 0 to 21) (P < 0.05) on the food conversion ratio (FCR). At the low level of lactose, there was a significant improvement in FCR as the levels of seaweed extract increased to 4 g/kg (P < 0.01). At the medium level of lactose, there was a significant improvement in FCR as seaweed extract increased to 2 g/kg. However, there was no significant effect of seaweed extract on FCR at the high levels of lactose (P > 0.05). There was a linear increase in average daily feed intake (ADFI) during the experimental period (days 0 to 21) (P < 0.05) as levels of seaweed extract increased. There was a linear increase in ash digestibility (P < 0.01) during the experimental period (days 0 to 21) as the level of lactose increased. There was a quadratic decrease (P < 0.01) in nitrogen (N) and neutral detergent fibre digestibility as the levels of lactose increased. In conclusion, pigs responded differently to the inclusion levels of seaweed extract at each level of lactose supplementation. The inclusion of a laminarin-fucoidan extract in piglet diets may alleviate the use for high-lactose diets (>60 g/kg) and would also alleviate some of the common problems that occur post weaning.
    animal 01/2009; 3(1):24-31. DOI:10.1017/S1751731108003017 · 1.78 Impact Factor
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