Phytase from Citrobacter koseri PM-7: Enhanced production using statistical method and application in ameliorating mineral bioaccessibility and protein digestibility of high-phytate food.

The present study was aimed at enhancing phytase (Phy-Ck) production from Citrobacter koseri PM-7 using response surface methodology (RSM) and improving the bioaccessibility of minerals (Fe and Zn) and protein digestibility in high-phytate food using Phy-Ck. A five-variable and three-level central composite design of RSM using wheat bran (6.681%, w/v), inoculum level (2.5%, v/v), and triton X-100 (0.2%, v/v) resulted in up to 5.57-fold (1.047 U/ml) improvement in Phy-Ck yield from C. koseri PM-7 when compared with fermentation media I and II. The model was successfully validated in the design space by taking a random set of variable combinations. Treatment of high-phytate food with partially purified Phy-Ck showed improvement in mineral bioaccessibility maximally for defatted sesame flour (DSF) (Fe 45.5%; Zn 50.7%) followed by wheat flour (WF) (Fe 13.5%; Zn 14.4%), green gram flour (GGF) (Fe 0.7%; Zn 3.8%) and defatted groundnut flour (DGF) (Zn 5.6%). The in vitro protein digestibility (IVPD) of WF increased from 48.83 to 65.04%, GGF from 45.04 to 57.12%, and DSF from 47.34 to 55.7% after Phy-Ck treatment.

Dietary adequacy of Indian children residing in an urban slum--analysis of proximal and distal determinants.

The influences of proximal and distal determinants of dietary adequacy of children from an urban slum in India were analyzed. Children numbering 271 (5-14 years) and their mothers were enrolled for the study. Intake of all nutrients except protein was inadequate in the dietaries of children. Among distal determinants, associations were found between (i) calorie intake and maternal nutritional status; (ii) protein, iron and B-complex intakes and economic status, and (iii) retinol, calcium and fat intakes and family size. Literacy status was not associated with dietary adequacy. Age of children and economic status of family were important determinants of dietary adequacy of children from slum area.