International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 7 (2013) pp. 35-43
Content of some minerals and their bioavailability in selected popular rice varieties from Bangladesh
Sonia Tamanna1 , Sayma Parvin1 , Sanjay Kumar1 , Alak K Dutta1 , Aysha Ferdoushi1 , M Ali Siddiquee , Sunil K Biswas and M Zakir H Howlader1*
1Department of Biochemistry and Molecular biology, University of Dhaka, Dhaka-1000, Bangladesh Grain quality and Nutrition Laboratory, Bangladesh Rice Research Institute (BRRI), Gazipur, Dhaka, Bangladesh *Corresponding author e-mail:
Rice grain is the staple food for over half of the world s population especially in the developing countries as such, is an important source of essential minerals. Mineral bioavailability in rice could be improved by the selection of varieties with high Fe, Zn, Ca and Se as well as low PA content. Therefore, the study was undertaken to investigate the variations of Fe, Zn, Ca, Se and PA content in some popular high yielding BRRI varieties consumed in Bangladesh as well as to estimate the potentially inhibiting effect of phytate on the bioavailability of iron, zinc, calcium and selenium by measuring their molar ratios. The study also investigated the effect of morphology of rice kernels on these parameters. For this purpose, we elected 8 BRRI (Bangladesh Rice Research Institute) developed varieties (BR-3, BR-11, BR-16, BRRI Dhan-26, BRRI Dhan-28, BRRI Dhan-29, BRRI Dhan-30, BRRI Dhan-40 and two local varieties (Pajam and Chinigura) and categorized as parboiled and unparboiled on the basis of parboiling and thus the effect of parboiling was also studied. The mean value of phytic acid content for parboiled and unparboiled group was found to range between 4.25 to 6.65 mg/g and 4.05 to 6.35 mg/g, respectively. The highest amount of phytic acid content was found in BR-3 (6.65 ± 0.27 mg/g) and BR-11 (6.65 ± 0.05 mg/g) among parboiled samples. The range of iron and zinc content in the parboiled group were 0.017 to 0.044 mg/g, 0.022 to 0.070 mg/g and that in the unparboiled group were 0.020 to 0.044 mg/g, 0.015 to 0.074 mg/g respectively. The zinc content varies greatly from rice to rice. The results of the mineral contents and PA content can be interpreted in terms of expected bio- availability. Despite the variation in mineral contents, in all cases the PA present is expected to render most mineral present unavailable. And thus may impair the bioavailability of the mineral in the body.
Phytate; Iron; Zinc; Calcium and Selenium bioavailability; BRRI varieties; molar ratios.