Kyyaly, Aref and Powell, Chris (2015) Potential for iron enriched yeast in recovery of rats from iron deficiency. In: British Yeast Group Meeting 2015 (BYG 2015), 25-27 Mar 2015, Manchester, UK. (Unpublished) Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/28831/1/aref%20byg2015.pdf Copyright and reuse: The Nottingham eprints service makes this work by researchers of the University of Nottingham available open access under the following conditions. This article is made available under the University of Nottingham End User licence and may be reused according to the conditions of the licence. For more details see: http://eprints.nottingham.ac.uk/end_user_agreement.pdf A note on versions: The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher s version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. For more information, please contact eprints@nottingham.ac.uk
Potential for iron enriched yeast in recovery of rats from iron deficiency M. Aref Kyyaly Chris Powell El-Shahat Ramadan
Baker s yeast in bread The primary roles of baker s yeast in bread making are: To increase the volume of the dough by evolving carbon dioxide as a result of alcoholic fermentation of sugars in the dough. To bring about a change in structure and texture in the dough as a result of stretching caused by formation of carbon dioxide bubbles. Additional roles include: Contribution to the flavour of bread. Contribution to the nutritional status of bread
Iron deficiency Iron deficiency is the most common nutritional deficiency Especially in developing countries Significant public health problem among children and women of childbearing age worldwide The most obvious manifestation of iron deficiency in humans is anemia There are 2 types of iron in the diet; haem iron (protein associated) and non-haem iron The absorption of non-haem iron varies greatly from 2% to 100% Influenced by different factors (iron status in body, solubility of iron salts) Haem iron is not affected by ingestion of other nutritional components Constant absorption rate of 20-30% The haem molecule is absorbed intact and the iron is released in the mucosal cells
Aims of this work Preparation of iron-enriched baker s yeast by supplementation of growth media with iron. Determination the impact of ingesting iron-enriched baker s yeast on anemia in experimental rats
Experimental design Preparation of iron enriched yeast by cultivation with different concentrations of iron salt Analysis of the effect of iron enrichment on baking properties Feeding anemic rats on diet supplemented with iron enriched yeast Evaluation of this treatment compared to classic treatment (inorganic salts) Determination of iron bioavailability Analysis of blood and histological parameters
Iron enrichment of yeast and its use as feed in treatment of anemia A-preparation of iron enriched yeast Different iron salts were used to determine best salt for growth based on yield of cells. Iron(III) Sulphate Iron (III) Chloride Ammonium Iron (III) Citrate Yeast cells were grown in presence of different concentrations of iron to determine The effect of iron concentration on the yield of cells Leavening ability Iron accumulation in yeast
Yield of cells % Leavening ability (ml) Iron accumulation (mg/gr) 50 18 40 16 14 30 12 10 20 8 6 10 4 2 0 ctrl 0.50% 1% 2% 4% 0 ctrl 0.50% 1% 2% 4% Iron in medium Iron in medium Baking property 30 25 20 15 10 5 Iron content in yeast 0 ctrl 0.50% 1% 2% 4% Iron salt concentration Yield of cells
B-feeding on iron enriched yeast Ctrl Group Group 1 Group 2 Group 3 Group 4 Group 5 All groups except Ctrl were fed on iron deficient diet for 3 weeks Group 1 Group 2 Group 3 Group 4 Group 5 4 weeks 4 weeks 4 weeks 4 weeks 4 weeks Fe deficient diet Basal diet + iron salt Fed on basal diet 30mg/kg diet all the experiment Basal diet + iron salt 30mg/kg diet+ 1gr/kg diet dry yeast Basal diet + iron enriched yeast 15mg Fe/kg diet Basal diet + iron enriched yeast 30mg Fe/kg diet
Food efficiency and iron bioavailability of rats in different treatments Feed efficiency: A measure of an animal's efficiency in converting feed mass into body weight Feed efficiency % = Body weight increase / total food intake Iron bioavailability is the extent to which iron is absorbed from the diet and used for normal body functions. A function of the relationship between body weight and total haemoglobin content
feed efficiency % Iron bioavaliability % Food efficiency and iron bioavailability of rats in different treatments 14 12 10 8 6 40 30 20 10 4 2 0 ctrl 1 2 3 4 5 0 Ctrl 1 2 3 4 5 feed efficiency of different groups -10 Rat groups iron bioavailability of different groups
Livers relative weight % Spleens relative weight % Hearts relative weight % Relative weight of organs from rats within each test group 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0.0 Heart Ctrl 1 2 3 4 5 4.0 3.5 Liver 0.6 spleen 3.0 2.5 2.0 1.5 0.5 0.4 0.3 1.0 0.5 0.0 Ctrl 1 2 3 4 5 0.2 0.1 0.0 Ctrl 1 2 3 4 5
transferritin saturation % Serum iron (umol/l) Final hemoglobin concentration mg/l total iron binding capacity (umol/l) Analysis of blood parameters from rats within each test group 180 160 140 120 100 80 60 40 20 0 Hemoglobin Ctrl 1 2 3 4 5 Rat groups 70 60 50 40 30 20 10 0 Total iron binding capacity Ctrl 1 2 3 4 5 70 60 50 40 30 20 10 0 Transferritin Ctrl 1 2 3 4 5 35 30 25 20 15 10 5 0 Serum iron Ctrl 1 2 3 4 5 Rat groups
Iron (µmol/g ) Iron (µmol/g ) Iron accumulation in tissues Spleen Liver 7 6 5 4 3 2 1 0 Ctrl 1 2 3 4 5 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 Ctrl 1 2 3 4 5 Rat groups Rat groups
Rat liver sections from each sample group Ctrl: Basal diet all experiment G1: Iron deficient diet all experiment G2: Basal (inorganic)treatment G3: Basal treatment + dry yeast G4: enriched yeast 15 mg/kg diet G5: enriched yeast 30 mg/kg diet Images reflect H&E staining in each instance
Rat heart sections from each sample group Ctrl: Basal diet all experiment G1: Iron deficient diet all experiment G2: Basal (inorganic)treatment G3: Basal treatment + dry yeast G4: enriched yeast 15 mg/kg diet G5: enriched yeast 30 mg/kg diet Images reflect H&E staining in each instance
Rat spleen sections from each sample group The spleen functions as a biological store of iron in the body Dark spots indicates iron disposition in the spleen tissue of rats ctrl G5 G2 G4 G3 G1 Images reflect Prussian Blue staining in each instance
Conclusions Yeast iron enrichment was successfully achieved: Using 1 % Ammonium iron(iii)citrate Without effecting dough rising power Iron enriched diets led to: Improved blood parameters Feed efficiency Iron bioavailability Histological parameters Feeding anemic rats with organic iron via ingestion of enriched yeast led to: Greater improvement over non-organic supplements for all parameters Data was similar for supplementation with organic iron at both 15 and 30 mg Fe/Kg
Further investigations Current work at UON Analysis of the potential for applying the enrichment process using an industrial growth medium (molasses) The effect of iron enrichment on the cellular protein profile in a range of baker s yeast strains The effect of iron enrichment on loaf properties (leavening, odour and taste) The potential for iron-enriched bread as a protectant and/or treatment for iron deficiency. Aref.Kyyaly@nottingham.ac.uk
Acknowledgments Deep thanks to: University of Nottingham for hosting me Dr. Chris Powell for his support Council for At-Risk Academics (CARA), for their support in UK Aleppo Baker s yeast factory, Syria for yeast strains Cairo University, Egypt, where this work was initiated